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Input Text: Answer the following question given this paragraph: 

Facial Bones of the Skull The facial bones of the skull form the upper and lower jaws, the nose, nasal cavity and nasal septum, and the orbit. The facial bones include 14 bones, with six paired bones and two unpaired bones. The paired bones are the maxilla, palatine, zygomatic, nasal, lacrimal, and inferior nasal conchae bones. The unpaired bones are the vomer and mandible bones. Although classified with the brain-case bones, the ethmoid bone also contributes to the nasal septum and the walls of the nasal cavity and orbit.


Q: The paired bones of the skull are the palatine, zygomatic, nasal, lacrimal, inferior nasal conchae bones, and what else?

 Choices:

- elongated

- maxilla

- minilla

- ventral

A:

Target Text: maxilla

#### Retrieved Documents ####

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Retrieved Text: Facial Bones – What Bones Form The Face?
Physiology ▶ Cardiovascular System ▶ Facial Bones – What Bones Form The Face?
The paired bones of the face are the maxillae, palatine bones, zygomatic bones, lacrimal bones, nasal bones, and inferior nasal conchae. The single bones are the vomer and mandible. The maxillae (mak-sil’-e) form the upper jaw. Each maxilla is formed separately, but they are joined at the midline during embryonic development. The maxillae articulate with all of the other facial bones except the mandible. The palatine processes of the maxillae form the anterior portion of the hard palate (roof of the mouth and floor of the nasal cavity), part of the lateral walls of the nasal cavity, and the floors of the orbits.
Each maxilla possesses an inferiorly projecting, curved ridge of bone that contains the teeth. This ridge is the alveolar process, and the sockets containing the teeth are called alveoli (singular, alveolus). The alveolar processes unite at the midline to form the U-shaped maxillary alveolar arch. A large maxillary sinus is present in each maxilla just inferior to the orbits.
The palatine (pal’-ah-tin) bones are fused at the midline to form the posterior portion of the hard palate. Each bone has a lateral portion that projects superiorly to form part of a lateral wall of the nasal cavity.
The zygomatic bones (cheekbones) form the prominences of the cheeks and the floors and lateral walls of the orbits. Each zygomatic bone has a posteriorly projecting process, the temporal process, that extends to unite with the zygomatic process of the

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Retrieved Text: The Viscerocranium - want to learn more about it?
The viscerocranium (or splanchnocranium) is one of the two areas that make up the skull. It is situated anteriorly to the neurocranium which partly encapsulates it posteriorly, both from above and below.
The viscerocranium comprises several bones that form the skeleton of the face as well as parts of the jaw (facial skeleton).
The nasal bones are a pair of bones that sit at the roof of the face and create the initial contour of the nose known as the bridge of the nose. They meet in the midline with one another and additionally articulate with the frontal bone superiorly via the frontonasal suture and the maxilla laterally via the nasomaxillary sutures.
The maxilla makes up the largest portion of the face and has the most muscle tissue attached to it, which is responsible for facial expressions. As with the nasal bones, it also connects to all the bones within the bony orbit (except the frontal bone).
The zygomatic bone is the bridge between the neurocranium and the viscerocranium. It forms the lateral prominences of the face (“cheekbones”) where the zygomatic and temporal portions of the zygomatic arch meet each other. It also articulates with the maxilla via the zygomaticomaxillary suture and the frontal bone via the frontozygomatic suture. Inside the bony orbit it contacts the frontal bone, the sphenoid bone and the maxilla.
The lacrimal bone can be found on the medial wall of the bony orbit. It houses the lacrimal sac and supports the contents of the eye socket. Anteriorly it

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Retrieved Text: registration process, enter the code below to get started today.
Typesetting by Carol Pierson, Chernow Editorial Services, Inc.
Rhoton, Albert L., 1932–2016, author.
Amador Valverde, Vicent Teruel Marti.
with the state of knowledge at the time of production of the book.
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Thieme Publishers Rio de Janeiro, Thieme Publicações Ltda.
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translating, preparation of microfilms, and electronic data processing and storage.
especially his wife Joyce, for their warm welcome to all the fellows and for their support of our work through the years.
To all the patients around the world who are, were, and will be saved by Professor Rhoton´s teachings.
their generous gift to those who benefit from a better study of the anatomy.
To our families for their unconditional support and love.
in which the law becomes manifest.
with English and Latin descriptors for easy cross-reference with other resources.
take notice of this work.
for the reader. The 3D images can be projected on any 3D television or computer to take full advantage of this outstanding collection.
not take the trouble to attend it are in no doubt at all.
1. Rudolf Virchow. In Cellular-Pathologie, Archiv für pathologische Anatomie und Physiologie und fur klinische Medizin 1855;8:19, as translated in Lelland J. Rather, Cellular Pathology, Disease, Life, and Man: Selected Essays by Rudolf Virchow 1958:84.
in Edward W. Adams, Founders of Modern Medicine II: Giovanni Battista Morgagni, Medical Library and Historical Journal 1903;1:27.
rests now with the reader to judge this.
We worked on most of the dissections for this project from 2011 to 2013.
labeled thousands of anatomical structures in English and Latin.
each chapter

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Retrieved Text: Skull - want to learn more about it?
The human skull consists of about 22 to 30 single bones which are mostly connected together by ossified joints, so called sutures. The skull is divided into the braincase (cerebral cranium) and the face (visceral cranium). Its main task is the protection of the most important organ in the human body: the brain.
The brain is almost entirely enclosed by the cerebral cranium with the exception of the foramen magnum and other foramina at the skull base which serve as entry and exit point for blood vessels and cranial nerves. Also, the skull provides support for all of the facial structures.
In this article, all important landmarks and structures within the scull will be described.
These are the three most significant of all 33 sutures which are formed by the human skull bones.
The skull base is the caudal boundary of the cerebral cranium. Looking at it from the inside it can be subdivided into the anterior, middle and posterior cranial fossae. The skull base comprises parts of the frontal, ethmoid, sphenoid, occipital and temporal bones.
The face is referred to as all skull bones fronto-caudally connected to the cerebral cranium. Prominent representatives are the maxilla (upper jaw) and the mandible (lower jaw). The orbita and the nasal cavity are formed by the zygomatic, nasal, palatine, lacrimal bones, the vomer and the inferior nasal concha (lower turbinate).
Introduction to the bones that make up the skull.
Most foramina in which relevant nerves and blood vessels pass through are located at the base of the skull. In

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Retrieved Text: The head and neck anatomy describes the structures that comprise the head and neck regions of the body. It consists of the muscles, bones, blood vessels, glands, brain, spinal cord as well as other organs located in the head and neck area. These areas are the most common area of study of neurologists, otorhinolaryngologist, ophthalmologists, dentists, surgeons as well as endocrinologists.
One of the most important areas in the head and neck is the skeletal system that helps protect and contain the important organs in the area. The head is located on the superior portion of the vertebral column with the skull attached on the first cervical vertebrae. The head and neck skeletal system comprise the upper portion of the axial skeleton. These bones include the skull, cervical spine, hyoid bone and the auditory ossicles.
The skull consists of 8 bones fused together to form the strong cranium protecting the brain. These include 2 frontal bones (bones forming the forehead), 2 parietal bones (bones forming the roof of the head), 2 temporal bones (bones forming the sides of the ehad) and 2 occipital bones (bones forming the back of the skull). These bones are fused together to form the strong skull. The skull also consists of the facial bones including the maxilla, zygomatic, mandible, palatine, lacrimal, nasal, inferior conchae and vomer. One of the important joints in the skull is the temporomandibular joint, which connects the mandible to the temporal region of the cranium. It allows for the opening and closing of the mouth, clenching of the teeth

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Retrieved Text: Vomer - want to learn more about it?
The vomer is a singular bone that runs vertically within the nasal cavity, separating the left and right sides.
When the skull is completely assembled, it can only be seen through the nasal orifice, anteriorly. This cranial structure runs caudally in an anterior and inferior direction, so that from a lateral point of view it looks like a diagonal rectangle (or a plough as it is more commonly known). The entire bone is ossified by means of the intramembranous pathway.
The vomer is part of the nasal septum which follows the midline of the viscerocranium and creates the division between the two symmetrical sides of the nasal cavity. To be exact, the vomer forms the posterior inferior aspect of the septum in between the perpendicular plate of the ethmoid bone anterosuperiorly and the palatine bone posteroinferiorly. In addition, the maxilla links to the vomer anteriorly and inferiorly, the sphenoid bone posteriorly and the nasal cartilage anteriorly.
The posterior border, however, is not attached to any bones but soft tissue, making it one of the few bones of the skull which does not fully articulate to other bones.
The vomer is a singular bone that runs vertically within the nasal cavity, separating the left and right sides. It runs caudally in an anterior and inferior direction. The vomer is part of the nasal septum which follows the midline of the viscerocranium and creates the division between the two symmetrical sides of the nasal cavity. The vomer articulates with the palatine, maxilla, ethmoid and sphenoid

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Retrieved Text: Either of a pair of cavities separated by a septum and located between the nasopharynx and anterior nares.
the cavity in which the olfactory organs of vertebrate animals are located. In terrestrial vertebrates and in man, the nasal cavity is also the initial division of the respiratory tract.
The nasal cavity is unpaired in cyclostomes and paired in fish. In all pulmonate organisms, the paired nasal cavity opens to the outside through external nasal orifices. The nasal and oral cavities are connected by means of choanae in lungfishes, amphibians, the majority of reptiles, and birds. In animals with a hard palate—crocodiles, mammals, and man—the nasal cavity is connected with the nasopharynx; in this case, the posterior section of the nasal cavity extends into the nasopharyngeal canal. In amniotes and man, the anterior section of the nasal cavity is called the vestibule.
In all terrestrial vertebrates the nasal cavity is divided by the maxilloturbinal bone into two sections: the superior nasal meatus and the inferior nasal meatus. In birds and the majority of mammals the superior nasal meatus contains the concha nasalis, or the turbinate bone. In mammals and man the posterior section of the nasal cavity contains the conchae of the ethmoid bone, which are covered by olfactory epithelium. All terrestrial vertebrates have a nasolacrimal canal that connects the eye socket with the nasal cavity; in most of these animals, Jacobson’s organ is formed by an outgrowth of the nasal cavity. In crocodiles, birds, and especially mammals and man, the nasal cavity is connected with the air cavities in

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Retrieved Text: Leone Gold, Maria Eugenia.; Brusatte, Stephen.; Norell, Mark.
Archosaurs and mammals exhibit skeletal pneumaticity, where bone is infilled by air-filled soft tissues. Some theropod dinosaurs possess extensively pneumatic skulls in which many of the individual bones are hollowed out by diverticula of three main cranial sinus systems: the paranasal, suborbital, and tympanic sinuses. Computed tomography (CT scanning) permits detailed study of the internal morphology of cranial sinuses. But only a few theropod specimens have yet been subjected to this type of analysis. We present CT scans of the remarkably preserved and disarticulated skull bones of the long-snouted tyrannosaurid theropod Alioramus. These scans indicate that Alioramus has extensive cranial pneumaticity, with pneumatic sinuses invading the maxilla, lacrimal, jugal, squamosal, quadrate, palatine, ectopterygoid, and surangular. Pneumaticity is not present, however, in the nasal, postorbital, quadratojugal, pterygoid, or angular. Comparisons between Alioramus and other theropods (most importantly the closely related Tyrannosaurus) show that the cranial sinuses of Alioramus are modified to fill the long-snouted skull of this taxon, and that Alioramus has an extreme degree of cranial pneumaticity compared to other theropods, which may be the result of the juvenile status of the specimen, a difference in feeding style between Alioramus and other theropods, or passive processes. Based on these comparisons, we provide a revised terminology of cranial pneumatic structures and review the distribution, variation, and evolution of cranial pneumaticity within theropod dinosaurs. This review illustrates that most theropods possess a common "groundplan" in which the maxilla and lacrimal are pneumatized, and that various theropods modify this groundplan by pneumatizing

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Retrieved Text: The ethmoid bone (also ethmoidal bone, ethmoid, latin: os ethmoidale) is an unpaired bone of the skull that contributes to the medial wall of the orbit, the nasal cavity and the nasal septum. The ethmoid bone includes the cribriform plate with openings that transmit the olfactory nerves (CN I), and it also houses paranasal sinuses called the ethmoidal air cells.
The cribriform plate of the ethmoid is a part of the ethmoid bone situated in the horizontal plane, covering the ethmoidal incisure. It forms the roof of the nasal cavity and part of the anterior cranial fossa of the internal cranial base. The cribriform plate has small openings which transmit the fibers of the olfactory nerves (CN I) from the olfactory epithelium (nasal cavity) to the brain (cranial cavity).
The perpendicular plate of the ethmoid is a part of the ethmoid bone situated in the sagittal plane below the cribriform plate. The lower part of the perpendicular plate forms the posterior nasal septum, while the upper part rises above the cribriform plate as the crista galli.
The ethmoidal air cells are air filled spaces in the ethmoidal labyrinth of the ethmoid bone belonging to the paranasal sinuses. There can be distinguished anterior, middle, and posterior ethmoidal air cells.
The orbital plate of the ethmoidal labyrinth is a thin bony plate found in the ethmoid bone, covering the ethmoidal cells from the orbital side and forming the lateral surface of the labyrinth.
The superior nasal conchae and the middle nasal conchae are a part of the ethmoid bone, while the inferior nasal

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Retrieved Text: Between the supraorbital margins the squama projects downward to a level below that of the zygomatic processes; this portion is known as the nasal part and presents a rough, uneven interval, the nasal notch, which articulates on either side of the middle line with the nasal bone, and laterally with the frontal process of the maxilla and with the lacrimal. The term nasion is applied to the middle of the frontonasal suture. From the center of the notch the nasal processprojects downward and forward beneath the nasal bones and frontal processes of the maxillæ, and supports the bridge of the nose.

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Retrieved Text: The light microscopic features of the mucous membrane of intact inferior nasal concha are described. A proposal is made to standardize the terminology of tissue deep to the basement membrane as superficial or deep tunica propria.
The range of epithelia found and the distribution of the various cell types and fibers present in the conchae are described.
The inferior nasal concha is one of the turbinates in the nose. It extends horizontally along the lateral wall of the nasal cavity and consists of a lamina of spongy bone, curled upon itself like a scroll.
A nasal concha is one of the curved bones that make up the upper portion of the nasal cavity. There are several different conchae in the nose, such as the inferior concha, medial concha and superior concha.
The incidence of middle turbinate pneumatization, or concha bullosa, has been well described in the literature. However, to our knowledge, no study has evaluated concha bullosa in relation to nasal septal deviation.
We sought to analyze the incidence of concha bullosa and any correlation with nasal septal deviation and paranasal sinus disease.

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Retrieved Text: Motor nucleus lies in pons.
Superior salivatory nucleus: in pons, parasympathetic secretomotor to lacrimal, submandibular, and sublingual glands.
Nucles solitarius: in medulla, sensory, carries taste sensation from the tongue.
Motor fibers form the motor root, while parasympathetic and sensory fibers join to form the sensory root (nervus intermedius).
The 2 roots emerge on the side of the brain stem, at junction between pons & medulla to cross CPA to I.A.M. Controlled by pyramidal & extrapyramidal fibers.
Labyrinthine segment: runs in the I.A.C superior to VIII & anterior to superior vestibular nerve, runs laterally to medial wall at geniculate ganglion.
Tympanic (horizontal) segment: starts at geniculate ganglion, curves to form 1st genu, runs backwards in medial wall till the posterior wall.
Mastoid (vertical) segment: Runs inferiority (2nd genu), lies antero inferior to lat. SCC, then vertically downwards to leave skull at stylomastoid foramen.
Enters parotid gland >> divides into terminal motor branches.
a) Greater superficial petrosal: arises at geniculate ganglion >> secreto motor parasympathetic to lacrimal, nasal, palatine glands.
b) Nerve to stapedius: motor supply to stapedius.
c) Chorda tympani: exit just above stylomastoid foramen to enter ME >> carries taste from ant. 2/3 of tongue & secretomotor parasympathetic to sub lingual and sub mandibular glands.
Two motor branches to stylohyoid & post belly of digastric.
Posterior auricular nerve: motor to occipital belly of occipitofrontalis.
Temporal, zygomatic, buccal, mandibular & cervical supply muscles of scalp, face, auricles & platysma.

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Retrieved Text: Chapter 23. Nasal Cavity. In: Morton DA, Foreman K, Albertine KH. Morton D.A., Foreman K, Albertine K.H. Eds. David A. Morton, et al.eds. The Big Picture: Gross Anatomy New York, NY: McGraw-Hill; 2011. http://accessphysiotherapy.mhmedical.com/content.aspx?bookid=381&sectionid=40140031. Accessed April 23, 2019.
. "Chapter 23. Nasal Cavity." The Big Picture: Gross Anatomy Morton DA, Foreman K, Albertine KH. Morton D.A., Foreman K, Albertine K.H. Eds. David A. Morton, et al. New York, NY: McGraw-Hill, 2011, http://accessphysiotherapy.mhmedical.com/content.aspx?bookid=381&sectionid=40140031.
The nasal cavity is divided into two lateral compartments separated down the middle by the nasal septum. The nasal cavity communicates anteriorly through the nostrils and posteriorly with the nasopharynx through openings called choanae. The nasal cavities and septum are lined with a mucous membrane and are richly vascularized by branches of the maxillary, facial, and ophthalmic arteries. The nasal cavity receives innervation via branches of the olfactory [cranial nerve (CN) I], ophthalmic (CN V-1), and maxillary nerves (CN V-2).
Roof. Formed by the nasal, frontal, sphenoid, and ethmoid bones (cribriform foramina, which transmits CN I for smell).
Floor. Formed by the maxilla and the palatine bones. The incisive foramen transmits branches of the sphenopalatine artery and the nasopalatine nerve for general sensation from the nasal cavity and palate.
Medial wall (nasal septum). Formed by the perpendicular plate of the ethmoid bone, the vomer bone, and the septal cartilage.
Sphenoethmoidal recess. The space between the superior nasal concha and the sphenoid bone, with openings from the sphenoid sinus.
Superior meatus. The space inferior to the superior nasal concha, with openings from the posterior ethmoidal air cells.
Middle meatus. The space inferior to

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Retrieved Text: Creator Kirberger, R.M. Fourie, S.L.
Description A rostrocaudal (RCd) nasal view was developed in large breed mesaticephalic dogs using a complete, subsequently sectioned, skull and cadaver specimens to optimise the radiographic technique and evaluate normal anatomic features. Gelatin was placed in one nasal passage of the cadaver specimens to mimic the effects of nasal pathology. The latter specimens and 18 clinical cases with suspected nasal disease were evaluated to determine the usefulness of the RCd view compared to standard nasal views. An optimal RCd view was obtained with the dog in dorsal recumbency and the head symmetrically positioned with the hard palate perpendicular to the table using a table top technique with 8 : 1 grid, collimating to the nasal region and centring the primary beam on the philtrum. The dorsolateral aspects of the maxillary bone, the nasal bones, septal sulcus of the vomer, mucosa lined nasal septum and conchae could be seen. A centrodorsal more radiolucent area representing the ethmoid bone region was also visible. Gelatin soft tissue opacification of the nasal passage could be seen more clearly in RCd nasal view than in occlusal dorsoventral view. In clinical cases the RCd view was useful to build up a 3-dimensional image of nasal passage pathology as well as to detect nasal septum and osseous nasal border pathology not visible in other views. This view is particularly useful in cases where cross-sectional imaging modalities are not available or where the nasal investigation is limited by cost considerations.

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Retrieved Text: The spine is a very complex mechanical structure that is highly flexible yet very strong and stable. In the normal spine, regardless of your position or activity, including sleeping, there is always some type of physical demand being placed on it.
Provide structural support and balance for upright posture. The spine bears the load of the head, shoulders and arms, and upper body. The upper body weight is then distributed to the hips and legs. The spine attempts to keep the body's weight balanced evenly over the pelvis. This reduces the amount of work required by the spinal muscles and can eliminate muscle fatigue and back pain.
The normal adult spine is balanced over the pelvis, requiring minimal workload on the muscles to maintain and upright posture.
Loss of spinal balance can result in strain to the spinal muscles and deformity of the spine as it attempts to maintain an upright posture.
The top 7 vertebrae that form the neck are called the cervical spine and are labeled C1-C7.
The upper back, or thoracic spine, has 12 vertebrae, labeled T1-T12.
The lower back, or lumbar spine has 5 vertebrae, labeled L1-L5.
The sacrum and coccyx (tailbone) are made up of 9 vertebrae that are fused together to form a solid bone. The sacrum is labeled S1.
When viewed from the front or back, the normal spine is in a straight line, with each vertebra sitting directly on top of the other. A side-to-side curve in the spine is called a scoliosis.
The neck has a lordosis; it curves toward the back.
The thoracic spine has a

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Retrieved Text: These are some examples of how the Smithsonian's Center for Folklife and Cultural Heritage used objects in its collection to reflect on its 50-year anniversary in 2017. While these entries are related to music, the collection's full site is also included. Investigating how and why cultural objects are made and used can help stimulate students to connect to their heritage and be used by teachers to develop research, storytelling, songwriting, and general writing skills with their students.
A collection of images focusing on the Native Americans and their vanishing cultures due to Manifest Destiny.
1. Show the students a copy of the painting “Westward the Course of Empire Makes Its Way” by Emanuel Leutze (1861). Ask the students to spend a few moments observing the work in silence, noticing any details that draw their eyes. Ask the students to let their eyes touch every part of the canvas/picture.
3. At this point, ask the students to note anything that they do not see but would expect to be represented in the scene. Second Language Learners who have been in the USA for 2-3 years would probably have some general ideas about the history of the USA and may be able to offer such absences. If not, the teacher may need to point out that no Native Americans appear in the main scene. If the students do not notice the border of the work, point out that there are small scenes in the border that add content/connections to the main scene. Point out that two Native Americans appear there, small

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Retrieved Text: The objective of this study was to evaluate the relationship between variations of the lateral wall of the nasal cavity and septal deviation (SD). Coronal and axial paranasal sinus CT images of 115 individuals (65 females, 50 males) were reviewed and the presence of pneumatisation and hypertrophy of the conchae was evaluated. Pneumatisation of the concha was classified as lamellar concha bullosa (LCB), bulbous concha bullosa (BCB), or extensive concha bullosa (ECB). If bulbous and extensive conchae and hypertrophic conchae were bilateral the side on which it was greatest was accepted as the dominant concha. The relationship between these variations and nasal septum deviation was also taken into account. Eighty-six (74.8%) of the 115 subjects had SD. Of these, 20 were not affected by the size of the middle nasal concha (MNC) or inferior nasal concha (INC). Thirty-four cases had dominant MNC, 20 had dominant INC, and 11 had both dominant MNC and dominant INC, and all of which had SD towards the opposite side. In one case there was SD towards the side in which the MNC was dominant. Our data indicate that coexistence of pneumatisation or hypertrophy of the conchae and SD was more common in adults compared to the results of similar studies conducted with a wide range of age groups, including children. Thus the presence of SD together with a large concha increases with age. A prospective study, which will include infants, will elucidate the relationship between conchae and SD.
KEY WORDS: Nasal cavity: Middle nasal concha; Inferior nasal concha; Septal deviation.

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Retrieved Text: The individual gas-exchanging manhood, the lung, also is currently found in the thorax, in which its fragile tissues are protected from the bony and muscle thoracic cage. The lung stipulates the cells of your body using a constant stream of oxygen and also clears the bloodstream of this gaseous waste productcarbon dioxide, carbon dioxide. Atmospheric air is pumped in and out frequently via a system of pipes, also known as running airways, which combine the gas-exchange area with the exterior the human body. The airways can be split into lower and upper airway systems.
The top airway system contains the nose and the paranasal cavities (or Illness ), the pharynx (or neck ), and partially also the nasal cavity, because it could possibly be used for the breathing. The diaphragmcalled the key neural muscle, along with the intercostal muscles of the chest wall play a vital role by creating, under the constraint of the central nervous system, the bending activity within the lung. The muscles contract and expand the inner distance of the thorax, the bony frame of which can be formed from the bones and also the nasal passages. The participation of the lung and chest wall (muscles and ribs ) into respiration is explained below at The mechanisms of breathing. The bloodstream, as a provider for those gases, as well as the circulatory system (i.e., both the heart and blood vessels) are compulsory components of a functioning circulatory system (notice bloodflow; cardiovascular procedure ).
It’s subdivided into a left and right artery with a lean lateral

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Retrieved Text: On advice from Jake McGowan-Lowe (of Jake's Bones fame) I moved my fox head from the bucket of water to a bin full of compost only a few days after my recent post. It turned out to be excellent advice, because it decomposed quickly there and with virtually no discernable smell.
Sadly, on checking to see how it was coming along it was quickly clear that I would not be able to retrieve an intact skull. Juvenile animal skulls are notoriously delicate, as the bones are unfused; additionally, I had had some concerns that the head had already been damaged, and this proved to be the case. My guess is that a dog rolled on it, just as mine nearly did.
However, I do have the lower mandibles and several parts of the maxilla, zygomatic arch and nasal bones – and I have many of the teeth, including three of the four huge canines, two tiny upper incisors, two carnassial molars still in situ and several double-rooted premolars. I'll clean them in peroxide and see how they come out.

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Retrieved Text: Definition (MSH) One of the paired air spaces located in the body of the SPHENOID BONE behind the ETHMOID BONE in the middle of the skull. Sphenoid sinus communicates with the posterosuperior part of NASAL CAVITY on the same side.
Definition (NCI_NCI-GLOSS) A type of paranasal sinus (a hollow space in the bones around the nose). There are two large sphenoid sinuses in the sphenoid bone, which is behind the nose between the eyes. The sphenoid sinuses are lined with cells that make mucus to keep the nose from drying out.
Definition (NCI) Either of the paired paranasal sinuses, located in the anterior part of the body of the sphenoid bone and communicating with the superior meatus of the nasal cavity on the same side.

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Retrieved Text: Situated behind the socket of the eye: a postorbital bone.
The mesial margin runs from the preorbital angle to the postorbital angle and is hollowed dorsally by the lateropremesial depression.
dmk: dorsal maxilla kink, dmp: dorsal maxilla process, dms: dorsal maxilla process slope, fr: frontal, j: jugal, jlmsp: jugal/lacrimal/maxilla suture process, jms: jugal/maxilla suture, I: lacrimal, Imsp: lacrimal/maxilla suture process, rax: maxilla, n: nasal, nr: naris ridge, pfmsip: prefrontal/maxilla suture inferior-process, pfmssp: prefrontal/maxilla suture superior-process, pfr: prefrontal, pmp: posterior maxilla process, pms: premaxilla/maxilla suture, pmx: premaxilla, po: postorbital, t: teeth.
Head and body covered with small brown flecks, whitish below, several indistinct dark bands crossing back in some; upper surface of eye without papillae; scales covering snout, a small area anteroventral to eye, interorbit, occipital region, nape, postorbital and opercular regions; suborbital region naked; first dorsal fin with a single small isolated spine anteriorly; body with two dark brown bands below second dorsal fin; first and second dorsal, pectoral and pelvic fins with small, dark brownish spots along rays; caudal fin with 2 or 3 horizontal dark bars, a prominent yellow blotch near middle of fin when fresh; head length 29.
Anterior preorbital processes appear as small projections of the supraorbital crest, while the postorbital processes are more developed, with a rectangular plate shape, which in the anterolateral region are at the same level as the preorbital process.
The average condylo-canine length, maxillary toothrow length, mandibular too throw length, greatest length of skull, mandible length, posterior palatal width, zygomatic breadth, breadth of braincase, postorbital constriction and anterior palatal width of two

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Retrieved Text: (Solved) Where are the nasal conchae?
Where are the nasal conchae?
Solved Which of the following is not a function of the nasal conchae?
What is an alternate name for the bony nasal projections known as turbinates?

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Retrieved Text: (Rhinitis atrophica suum), a disease of swine, predominantly young animals, characterized chiefly by a sharp change in the form of the facial skull bones and particularly the nasal conchae (curved snout). The cause of the disease is not established. Hygienic conditions and feeding are of significance in the occurrence and distribution of the disease. Most susceptible to atrophic rhinitis of swine are sucklings (up to two or three weeks); quite often the carriers are young sows (65–75 percent). The incubation (latent) period of the disease is five to 15 days, the course of the illness is most often chronic. The ailing animals lose their appetite, become emaciated, and their growth is retarded; sneezing causes pyoid hemorrhages from the snout; there is often a disruption of motor coordination and strabismus. The economic damage caused by the disease is significant. Cases of atrophic rhinitis of swine have been recorded in many nations of the world. Treatment consists of antibiotics, sulfanilamides, and vitamins A and D. Prophylaxis includes the observance of hygienic requirements in tending and feeding and providing a diet that is balanced in terms of protein, vitamins, and minerals.

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Retrieved Text: For the internal cast of the cranium, see Endocast.
The endocranium in comparative anatomy is a part of the skull base in vertebrates and it represents the basal, inner part of the cranium. The term is also applied to the outer layer of the dura mater in human anatomy.
Human endocranium (pink fields), inner surface.
Structurally, the endocranium consists of a boxlike shape, open at the top. The posterior margin exhibit the foramen magnum, an opening for the spinal cord. The floor of the endocranium has several paired openings for the cranial nerves, and the anterior margin holds a spongy construction, allowing for the external nasal nerves to pass through. All bones of the structure derive from the cranial neural crest during fetal development.
The Ethmoid bone, lying behind the nose.
Paired prootic and opisthotic bones above each fenestra ovalis, fused to the petrous part of the temporal bones in mammals.
Paired exoccipital bones medially and a single basioccipital bone below the foramen magnum, part of the occipital bone in mammals.
The loosely connected skull of a perch.
While the endocranium is an integral part of the skull in mammals, birds and reptiles, its connection to the roofing parts of the skull is more loose in the lower vertebrates. In Agnathans and Chondrichthyes, the skull lacks the skull roof dermal elements, their whole cranium being composed of the endocranium, properly called a chondrocranium. In most Osteichthyes, the skull is only loosely joined, and the endocranial elements do not form a unit with the skull roof.
An endocast or endocranial cast is a cast made of

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Retrieved Text: Osseous hemangiomas are uncommon, constituting less than 1% of all osseous neoplasms. Most commonly affects maxilla, mandible & nasal bones. We report a case of an osseous hemangioma of nasal cavity. Cavernous hemangioma of the nose is a rare lesion and is one of the differential diagnosis of an intranasal bleeding mass.
Batsakis JG, Rice DH. The pathology of head and neck tumors: vasoformative tumors, part 9A. Head Neck Surg. 1981;3:231-9.
D. F. Hoffmann, J. Israel. Intraosseous frontal hemangioma. Head Neck. 1990;12(2):160-3.
S. J. Relf, G. B. Bartley, K. K. Unni. Primary orbital intraosseous hemangioma. Ophthalmology. 1991;98(4):541-7.
F. F. Fahmy, G. Back, C. E. T. Smith, A. Hosni. Osseous hemangioma of inferior turbinate. J Laryngol Otol. 2001;115(5):417-8.
Enzinger F, Weiss S. Hemangioma. In: Weiss SW, Goldblum JR, Folpe AL. Soft Tissue Tumor. 2nd ed. St Louis: Mosby; 1988: 837-890.
Webb CG, Porter G, Sissons GRJ. Cavernous hemangioma of the nasal bones: an alternative management option. J Laryngol Otol. 2000;114:287-9.
Fahmy FF, Back G, Smith CE, Hosni A. Osseous hemangioma of inferior turbinate. J Laryngol Otol. 2001;115:417-8.
Nakahira M, Kishimoto S, MiuraT, Saito H. Intraosseous hemangioma of the vomer: a case report. Am J Rhinol. 1997;11:473-7.
Engels T, Schörner W, Felix R, Witt H, Jahnke V. Kavernöses Hämangiom des Sinus maxillaris. HNO. 1990;38:342-4.
Bridger MWM. Haemangioma of Nasal Bones. J Laryngol Otol. 1976;90:191-200.
Sherman RS, Wilner D. The Roentgen diagnosis of haemangioma of bone. Am J Roentgenol. 1961;86:1146-59.
Osborn DA. Hemangioma of the Nose. J Laryngol Otol. 1959;73:174-9.
Nievert H, Bitchick EB. Primary Haemangioma of the nasal bone. Arch Otolaryngol. 1936;24:495-501.
Iwata N, Hattori K, Nakagawa T, Tsujimura T. Hemangioma of

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Retrieved Text: Paranasal sinuses. Coloured 3D computed tomography (CT) scan of the paranasal sinuses. The paranasal sinuses are spaces in the bones surrounding the eyes and nose, and the cheek bones of the upper jaw. They lighten the bones of the skull and reduce the weight of the head. They are connected to the nasal passages and are lined with mucous membranes. They can fill with fluid and secrete mucus during an infection.

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Retrieved Text: This historic 1912 paper by Schaeffer described development of the nasolacrimal passages.
See also by this author: Schaeffer JP. The sinus maxillaris and its relations in the embryo, child, and adult man. (1910) 10 2): 314-.
Modern Notes See also Carnegie stage 16, Carnegie stage 17, Carnegie stage 18, in Week 6 and Week 7 where the nasolacrimal groove can be seen on the head surface before fusing to enclose the duct in Carnegie stage 19.
A brief review of the literature on the nasolacrimal passages [laerimal duets (lachrymal canaliculi), lacrimal sac, nasolacrimal duct] shows that diverse views were from time to time advanced on the genesis and development of these passages Before considering the material studied in this investigation I Want to refer to some of the theories held by earlier Writers. I do not wish to give a complete resume on the history of the development, but rather in a brief manner indicate the evolution in our knowledge concerning the genesis and development of these passages.
v. Baer (’28~’37) thought that the nasolacrimal passages had their origin in a diverticulum from the ‘ Rachenhohle.’ His theoryl presumably was based upon hypothetical conclusions, since it is entirely unsupported.
Der Thranengang stillpt sich auch hier (in mammals) aus der Rachenhijhle gegen das Ange hervor und liegt Anfangs hintcr den Muscheln,~die nur, indem sie sich verlangern, sich iiber ihn ziehen. Uber‘Entwickelungsgeschichte der Thiere, Thiel 2, S. 219.
passages, but does not state his meaning clearly? He apparently thought that the nasolaerimal passages had their origin in a diverticulum or skin-fold (‘Hautfalte’) in the

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Retrieved Text: Paranasal sinuses, artwork. The paranasal sinuses are spaces in the bones surrounding the eyes and nose, and the cheek bones of the upper jaw. They lighten the bones of the skull and reduce the weight of the head. They are connected to the nasal passages and are lined with mucous membranes. The paranasal sinuses are: the frontal sinus (purple, in forehead), the ethmoid sinus (yellow), the sphenoid sinus (green) and the maxillary sinus (light blue).

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Retrieved Text: This real human skull features a non articulated mandible. Partial dentition on both upper and lower jaws with light deterioration along the front of the maxilla. Intact orbitals, nasal and inner ear conchae. Medium bone density and well fused sutures. Fantastic specimen to add to your collection.

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Retrieved Text: Developmental anomalies of the nose encompass a diverse group of conditions. In this article, embryologic development of the nose and nasal cavities are discussed, as well as anomalies of the nose to include nasal dermoids (eg, gliomas, encephaloceles, nasal clefts, proboscis lateralis, arhinia, polyrrhinia, nasopharyngeal teratoma, epignathus). Choanal atresia is discussed in a separate chapter.
During the third week of development, ectodermal cells in the caudal portion of the developing embryo proliferate and migrate medially and caudally to form the notochordal process. Concurrently, modified ectodermal cells invaginate in the midline of the caudal primitive streak. They then migrate between ectodermal and endodermal layers. Also during the third week, the ectoderm and endoderm of the cephalic region become adherent, forming the buccopharyngeal membrane, which represents the forward boundary of the primitive foregut. At the end of the third week, a midline neural groove develops along the dorsal surface of the embryo. This groove then thickens, deepens, and forms the neural tube, the cephalic end of which becomes the primary brain vesicles.
By days 20-30, mesodermal tissue condenses on either side of the midline and becomes the paraxial mesoderm (in the cephalic region). At this point, the buccopharyngeal membrane disappears, and the primitive nasal cavity forms.
At approximately 4.5 weeks, the centrally located stomodeum appears, which forms the center of the face. The first pair of pharyngeal arches surrounds the stomodeum. The stomodeum becomes surrounded by 5 mesenchymal prominences (ie, the maxillary and mandibular swellings, as well as the frontal prominence). The nasal placode, which arises from surface ectoderm, develops on

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Input Text: Answer the following question given this paragraph: 

4.3 Eukaryotic Cells Like a prokaryotic cell, a eukaryotic cell has a plasma membrane, cytoplasm, and ribosomes, but a eukaryotic cell is typically larger than a prokaryotic cell, has a true nucleus (meaning its DNA is surrounded by a membrane), and has other membrane-bound organelles that allow for compartmentalization of functions. The plasma membrane is a phospholipid bilayer embedded with proteins. The nucleus’s nucleolus is the site of ribosome assembly. Ribosomes are either found in the cytoplasm or attached to the cytoplasmic side of the plasma membrane or endoplasmic reticulum. They perform protein synthesis. Mitochondria participate in cellular respiration; they are responsible for the majority of ATP produced in the cell. Peroxisomes hydrolyze fatty acids, amino acids, and some toxins. Vesicles and vacuoles are storage and transport compartments. In plant cells, vacuoles also help break down macromolecules. Animal cells also have a centrosome and lysosomes. The centrosome has two bodies perpendicular to each other, the centrioles, and has an unknown purpose in cell division. Lysosomes are the digestive organelles of animal cells. Plant cells and plant-like cells each have a cell wall, chloroplasts, and a central vacuole. The plant cell wall, whose primary component is cellulose, protects the cell, provides structural support, and gives shape to the cell. Photosynthesis takes place in chloroplasts. The central vacuole can expand without having to produce more cytoplasm.


Q: Cells like a prokaryotic cell, a eukaryotic cell has a plasma membrane, cytoplasm, and ribosomes, but a eukaryotic cell is typically larger than a prokaryotic cell, has a true nucleus (meaning its dna is surrounded by a membrane), and has other membrane-bound organelles that allow for what?

 Choices:

- compartmentalization of functions

- replicating of functions

- misuse of functions

- scrobipalpa of functions

A:

Target Text: compartmentalization of functions

#### Retrieved Documents ####

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Retrieved Text: 2) All cells carry out life activities (require energy, grow, have a limited size). Function - Organelles are found here and substances like salts may be dissolved in the cytoplasm. 3. There are two types of ER: rough ER and smooth ER. BIO Lab: Cell Organelles Computer Lab. All cells, whether they are prokaryotic or eukaryotic, have some common features. which may be used to pull two cells in close contact, and perhaps to facilitate the transfer of genetic material. Every cell in your body contains organelles (structures that have specific functions). The nucleus, mitochondria and chloroplasts are all organelles. Within cells, organelles tend to cluster close to where they do their job. For instance, the TEM showed that mitochondria contained two membranes and.
All cells, whether they are prokaryotic or eukaryotic, have some common features that consists of a fluid portion called the cytosol and the organelles and other. Like our cells, bacteria cells have DNA and a plasma membrane. But bacteria There are two basic types of cells, prokaryotic cells and eukaryotic cells. They do not have a nucleus or other membrane-bound organelles. Most organelles are common to both animal and plant cells. However, plant cells also have features that animal cells do not have: a cell wall, a large central vacuole, Between these two layers is the intermembrane space.
You can do all this because you are made of cells — tiny units of life that are like There are two main types of cells, prokaryotic and eukaryotic. All cells have membranes (the building), DNA

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Retrieved Text: Living things consist of cells, and cells come in numerous types relating to the overall level of complexity of the organisms in which they are found. Archaea (blue-green algae, for example) and bacteria such as E. coli contain prokaryotic cells, while the more complex members of the Eukaryota domain contain eukaryotic cells.
The main difference between prokaryotic cells and eukaryotic cells is that the former do not contain a membrane-bound nucleus. The word "prokaryote" is derived from Greek words that mean "before nucleus." Prokaryotic cells contain fewer organelles or functional components than do eukaryotic cells. Their four main structures are the plasma membrane, cytoplasm, ribosomes and genetic material (DNA and RNA).
While some eukaryotic cells have cell walls, such as those in plants and fungi, almost all prokaryotic cells have them, and they are chemically distinct from those of eukaryotes. The walls give the organism stability, protection and its overall shape. The walls of bacteria consist of substances called peptidoglycans. Some prokaryotes have an outer capsule outside the cell wall, resulting in three layers from outside to inside: capsule, wall and membrane. Certain antibiotics, including penicillin drugs, target the cell walls of bacteria.
The cell membrane, which is common to all living things, consists of a structure called a phospholipid bilayer. It is so named because it includes two layers, each containing hydrophilic, or water-soluble, phosphate "heads" that face away from the middle of the membrane and hydrophobic "tails" that are not water soluble and face each other on the interior of the double layer. The membrane is selectively

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Retrieved Text: Our natural world also utilizes the principle of form following function, especially in cell biology, and this will become clear as we explore eukaryotic cells ( [link]). Unlike prokaryotic cells, eukaryotic cells have: 1) a membrane-bound nucleus; 2) numerous membrane-bound organelles such as the endoplasmic reticulum, Golgi apparatus, chloroplasts, mitochondria, and others; and 3) several, rod-shaped chromosomes. Because a eukaryotic cell’s nucleus is surrounded by a membrane, it is often said to have a “true nucleus.” The word “organelle” means “little organ,” and, as already mentioned, organelles have specialized cellular functions, just as the organs of your body have specialized functions.
Like prokaryotes, eukaryotic cells have a plasma membrane ( [link]), a phospholipid bilayer with embedded proteins that separates the internal contents of the cell from its surrounding environment. A phospholipid is a lipid molecule with two fatty acid chains and a phosphate-containing group. The plasma membrane controls the passage of organic molecules, ions, water, and oxygen into and out of the cell. Wastes (such as carbon dioxide and ammonia) also leave the cell by passing through the plasma membrane.
The plasma membranes of cells that specialize in absorption are folded into fingerlike projections called microvilli (singular = microvillus); ( [link]). Such cells are typically found lining the small intestine, the organ that absorbs nutrients from digested food. This is an excellent example of form following function.
The cytoplasm is the entire region of a cell between the plasma membrane and the nuclear envelope (a structure to be discussed shortly). It is made up of organelles suspended in the

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Retrieved Text: Explain the difference between cell morphology and arrangement.
What advantages do cell walls provide prokaryotic cells?
All cellular life has a DNA genome organized into one or more chromosomes. Prokaryotic chromosomes are typically circular, haploid (unpaired), and not bound by a complex nuclear membrane. Prokaryotic DNA and DNA-associated proteins are concentrated within the nucleoid region of the cell ( [link] ). In general, prokaryotic DNA interacts with nucleoid-associated proteins (NAPs) that assist in the organization and packaging of the chromosome. In bacteria, NAPs function similar to histones, which are the DNA-organizing proteins found in eukaryotic cells. In archaea, the nucleoid is organized by either NAPs or histone-like DNA organizing proteins.
The nucleoid region (the area enclosed by the green dashed line) is a condensed area of DNA found within prokaryotic cells. Because of the density of the area, it does not readily stain and appears lighter in color when viewed with a transmission electron microscope.
Prokaryotic cells may also contain extrachromosomal DNA, or DNA that is not part of the chromosome. This extrachromosomal DNA is found in plasmid s , which are small, circular, double-stranded DNA molecules. Cells that have plasmids often have hundreds of them within a single cell. Plasmids are more commonly found in bacteria; however, plasmids have been found in archaea and eukaryotic organisms. Plasmids often carry genes that confer advantageous traits such as antibiotic resistance; thus, they are important to the survival of the organism. We will discuss plasmids in more detail in Mechanisms of Microbial Genetics .
All cellular life synthesizes proteins, and organisms in all

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Retrieved Text: Gram positive bacteria : Bacteria that take up gram stain.
Gram negative bacteria : Bacteria that do not take up gram stain.
Cells which lack a well defined nucleus and membrane bound cell organelles. e.g., bacteria, cyanobacteria, mycoplasma.
e a well defined nucleus and membrane bound cell organelles. e.g., all protists, plants, animals and fungi cells.
gradient, i.e., from higher to lower concentration without the consumption of energy.
Active transport : Transport of molecules against concentrataion gradient, i.e., from lower to higher concentration with the consumption of energy (ATP). Polyribosome/polysome : A chain like structure formed when several ribosome are attached to a single mRNA.
PPLO : Pleuro Pneumonia Like Organisms.
(a) All living organisms are composed of cells and products of cells.
extra chromosomal DNA − plasmids.
wall and then plasma membrane.
surface area of plasma-membrane and enzymatic content.
the bacteria to attach with rocks and the host tissues.
subunits − 50S and 30S. Ribosomes are site of protein synthesis.
complex locomotory and cytoskeletal structures.
and provides barrier to undesirable macromolecules.
Plasmodesmata connect the cytoplasm of neighbouring cells.
• Ribosomes attached to outer surface.
• Site for synthesis of lipid.
are convex cis or forming face and concave trans or maturing face.
carbohyrases) which are active in acidic pH. Also called ‘Suicidal Bag’.
of ions and other substances.
protistis for digestion of food.
forms a number of infoldings called cristae.
is called stroma. Flattened membranous sacs called thylakoids in stroma.
Chlorophyll pigments are present in thylakoids.
Function : Site of photosynthesis.
Function : Site of protein synthesis.
Cilia are small structures which work like oar, which help in movement.
with plasma membrane. Core is called axoneme which has 9 + 2 arrangement.
matrix and

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Retrieved Text: cytoplasm: water-rich substance filling interior of cell; rich in nutrients, enzymes, ribosomes, etc.
chromosome(s): genetic information of cells; encodes all information to direct cell functions and biosynthesis. Made of double stranded DNA. DNA base sequence determines amino acid sequence of all proteins produced by cell.
-Prokaryotic cells have “small” ribosomes called 70S ribosomes.
-Eukaryotic cells in their cytoplasm have “large” ribosomes, called 80S ribosomes.
-tough resistant structures formed to protect bacterial DNA when conditions deteriorate; may survive centuries.

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Retrieved Text: Chatton gave the term prokaryote and eukaryote. Depending upon the nature of nucleus cells are classified. Incipient nucleus is present in prokaryotes, where as in eukaryotes well organised nucleus is present.
It is a single membrane system.
It is a double membrane system.
Cell wall surrounds the plasma membrane.
Cell wall surrounds the plasma membrane in some protists, most fungi and all plant cell. Animal cell lacks it.
Cell wall is composed of peptidoglycans. Strengthening material is murein.
It is composed of polysaccharide. Strengthening material is chitin in fungi and cellulose in others plants.
Cell membrane bears respiratory enzymes.
Cytoplasm lacks cell organelles e.g., Mitochondria, ER, Golgi body etc.
Cytoplasm contains various cell organelles.
Ribosomes are only 70 S type.
Ribosomes are both 80 S and 70 S type.
There are no streaming movements of cytoplasm.
Nuclear material is not enclosed by nuclear envelope and lies directly in cytoplasm. It is called nucleoid.
It is enveloped by nuclear envelope. Nucleus is distinct from cytoplasm.
DNA is circular and not associated with histones proteins.
Nuclear DNA is linear and associated with histone proteins extranuclear DNA is circular and histones protein free.
Sexual reproduction absent but parasexuality present.
Cell division is typically mitotic.
Mesokaryon : Dodge gave the term ‘Mesokaryon’ for dinoflagellates. These are intermediate type of cell organisation in dinophyceae of algae. In mesokaryotic there is present a true or eukaryotic nucleus with definite nuclear membrane and chromosomes.

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Retrieved Text: CELL is the fundamental structural and functional unit of all living organism and anything less than a complete cell has no independent existence.
In 1665, Robert Hooke observed a thin section of cork under a compound microscope, noticed a honey-comb like compartments. He coined the term “Cell”.
In 1674, Anton Von Leeuwenhoek first saw and describe the living cell.
Later, in 1831, Robert Brown discovered the nucleus in the root cells of orchids.
The invention of the microscope & its improvement leading to the electron microscope revealed all the structural details of the cell.
In 1838, Matthias Schleiden found that all the plant cells have essentially similar structure and have a cell wall.
In 1839, Theodore Schwann studied different types of animal cells and reported that cells had a thin outer layer which is today known as the ‘plasma membrane’. He also concluded that the presence of cell wall is a unique character of the plant cells. On the basis of this Schwann proposed the hypothesis that the bodies of animals & plants are composed of cells & products of cells.
Schleiden and Schwann together formulated the cell theory. This theory, however, didn’t explain as to how new cells were formed.
In 1855, Rudolf Virchow first explained that the cells divided and new cells are formed from pre-existing cells. He modified the hypothesis of Schleiden and Schwann to give the cell theory a final shape.
All living organisms are composed of cells and cell products.
CELL MEMBRANE – It is the outermost (in the animal cell including human cell) and inner to the cell wall (in

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Retrieved Text: What is a virus? Is it even a living organism?
This alien-looking thing is a virus. But is it prokaryotic or eukaryotic? Or neither? Or both? A virus is essentially genetic material surrounded by protein. That's it. So, is a virus prokaryotic or eukaryotic? Or neither? Or both?
Viruses, like the one depicted in Figure below, are tiny particles that may cause disease. Human diseases caused by viruses include the common cold and flu. Do you think viruses are prokaryotes or eukaryotes? The answer may surprise you. Viruses are not cells at all, so they are neither prokaryotes nor eukaryotes.
Cartoon of a flu virus. The flu virus is a tiny particle that may cause illness in humans. What is a virus? Is it a cell? Is it even alive?
Viruses contain DNA but not much else. They lack the other parts shared by all cells, including a plasma membrane, cytoplasm, and ribosomes. Therefore, viruses are not cells, but are they alive? All living things not only have cells; they are also capable of reproduction. Viruses cannot reproduce by themselves. Instead, they infect living hosts, and use the hosts’ cells to make copies of their own DNA. Viruses also do not have their own metabolism or maintain homeostasis. For these reasons, most scientists do not consider viruses to be living things.
An overview of viruses can be seen at http://www.youtube.com/watch?v=0h5Jd7sgQWY(23:17).
Viruses are neither prokaryotic or eukaryotic.
Viruses are not made of cells. Viruses cannot replicate on their own.
Most scientists do not consider viruses to be living.
Why are viruses considered parasites?
Describe the outside covering

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Retrieved Text: Are you looking for NCERT Class 8 Solution? Download NCERT Solution Class 8 Science Chapter 8 : Cell-Structure and Functions and prepare better for your examinations.
Question 1: Indicate whether the following statements are True (T) or False (F).
Question 2: Make a sketch of the human nerve cell. What function do nerve cells perform?
The function of a nerve cell is to transmit messages to the brain and also to take away messages from the brain to the receptor organs. Thus, it controls the working of different parts of the body.
Question 3: Write short notes on the following.
It is a fluid that fills the cell and occurs between the plasma membrane and the nucleus. Cell organelles such as mitochondria, ribosomes, Golgi bodies, etc. are suspended in the cytoplasm. The cytoplasm helps in the exchange of materials between cell organelles.
It is a double-layered membrane which separates the contents of the nucleus from the cytoplasm. The nuclear membrane has nuclear pores that allow the transfer of specific substances in and out of the nucleus.
It is a small spherical body that is not bound by any membrane.
These are thread-like structures that carry genes. Genes contain information necessary for the transfer of characteristics from the parents to the offspring. Thus, chromosomes play an important role in the inheritance of characteristics.
Question 4: Which part of the cell contains organelles?
Cytoplasm is the part of the cell that contains various organelles such as mitochondria, ribosomes, Golgi bodies, etc. Cytoplasm is a fluid that fills the cell and occurs between the plasma membrane and the nucleus.
Question

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Retrieved Text: Eukaryotes are organisms having very complex cellular structure. This article deals with eukaryotic cell cycle along with its phases and regulation.
Let's get to the roots of what eukaryotes are before we proceed upon discussing life cycle of a eukaryotic cell. Cells are the building blocks of life as a single cell, in itself, is a functional unit of life. Sometimes a single cell can compose an entire organism (lesser, unicellular life forms like bacteria) while on other occasions, a cluster, sometimes reaching a count of millions, of cells may combine together to take the shape of a higher organism like mammals, reptiles, etc. With regards to cell biology, based upon their structures and corresponding functions, cells can be classified under two broad categories - prokaryotic cells and eukaryotic cells. Let's take a brief look at each of these cell types and follow it up with a detailed study of the cycle of eukaryotic cells.
A prokaryotic cell is composed of a cell envelop which consists of a cell wall and a plasma membrane beneath the cell wall. Enclosed within this cell envelop is the cytoplasmic area that houses the cell genome (DNA or RNA, as the case may be) along with ribosomes and various other material. Although there exists a nuclear region in the cytoplasmic are, prokaryotic cells do not contain a nucleus. This is the most significant aspect that differentiates prokaryotic cells from eukaryotic cells. Archaebacteria and eubacteria are the two chief prokaryote life forms.
Eukaryotic cells are greater in dimension than prokaryotic cells. Eukaryotes have a

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Retrieved Text: Size of prokaryotic cell is smaller as compared to eukaryotic cells.
Nucleus is absent in prokaryotic cells and present in eukaryotic cells.
Nucleolus is also absent in prokaryotic and present in eukaryotic cells.
Membrane bound cell organelles are absent in prokaryotic and present in eukaryotic cells.
Only one chromosome is present in prokaryotic cell, whereas more than one chromosome is present in eukaryotic cells.
Mitosis occurs in eukaryotic cells, but not in prokaryotic cells.
Bacteria and cyanobacteria are examples of prokaryotic cell. All multicellular organisms like cells of plants and animals are examples of eukaryotes.

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Retrieved Text: 1: Cell Theory: The Three Principles | 1. All organisms are composed of one or more cells. 2. The cell is the basic unit of life. 3. New cells arise only from cells that already exist. | Cell Theory: The theory that cells form the fundamental, structural and functional units of all living organisms.
3: Theodore Schwann found that plants and animals were made up of cells and that the cells were their own living organism. Matthias Schlieden found that the nucleus and cell development were related. He also found that plant cells work two lives: one being it's own and one helping the plant. Robert Hooke originated the term cell by observing a tree and naming the holes cellulae. Rudolf Virchow found that all cells originate from an already existing cell. He found that cells reproduce by division.
4: Prokaryotic | Prokaryotes tend to be smaller in size with no nuclear membrane or nucleoli. it's chromosome arrangement in a single circular chromosome with no histones. It usually has a cell wall that is very chemically complex with no cytoskeleton.
5: Eukaryotic | Eukaryotes are larger in size with a true nucleus. it's chromosome arrangement is multiple linear chromosomes with histones. If it has a cell wall then it is chemically simple with a cytoskeleton.
6: Plant Cells | Plant cells are different from animal cells. The are shaped rectangularly with a cell wall that surrounds the cell membrane. Chloroplast allows plant cells to make their own food. It has one large vacuole that takes up 90% of the cells

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Retrieved Text: We have already discussed in detail the differences between plant cell and animal cells. Now let us see how these two cell types are similar.
1. Both plant cell and animal cell is Eukaryotic (with true nucleus or genetic material surrounded by a membrane).
3. Both plant cell and animal cell possess a well defined nucleus and cytoplasm, where genetic material DNA is surrounded by a nuclear membrane.
4. Most of the organelles like nucleus, mitochondrion, Golgi apparatus, endoplasmic reticulum etc are present in both plant cell and animal cell.
5. In both plants and animals cells, DNA is double stranded and complexed with histone proteins and proteins are synthesized by ribosomes in the cytoplasm.

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Retrieved Text: Plant cell structure is not included in all health science subjects (e.g. all courses in anatomy & physiology) but is is an important part of general biology. Basic cell biology is included in UK A-Level Biology and equivalent courses. It is also useful general knowledge for anyone working in life sciences. This page helps with the task: With the help of a diagram describe the structure of a plant cell.
Note: The diagram above is a general plant cell - so not a particular part of any specific plant. The labels in pink are links to pages of further information about the part of the plant cell indicated. The structures are not necessarily drawn to scale but in enough detail to aid recognition and to help students re-draw this diagram by hand to include in study notes or homework.
The structure of plant cells has similarities and differences compared with the structure of animal cells. The following table lists the parts of plant cells shown in the diagram above with brief notes about each of the structures types of organelles in plant cells.
Plant cells have cell walls - as compared with animal cells which do not have cell walls, and prokaryotic cells (bacteria) which do have cell walls but they are of a different construction than those of plant cells.
The main functions of plant cell walls are mechanical. Plant cell walls form part of a transport system called the apoplast system via which water and some solutes can pass through plant tissue via apoplastic pathways (along / through

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Retrieved Text: A prokaryotic cell does not contain any true nucleus. This is why it is called a cell with a primitive type of nucleus. The term nucleotide fits nice in this case. Nuclear materials in a prokaryotic cell are not surrounded by any nuclear membrane. They are dispersed in its cytoplasm. Though the cell organelles such as mitochondria, plastids, endoplasmic reticule etc. are not found in a prokaryotic cell, ribosomes are present in it. Only the unwrapped DNA constitutes the chromosomal structure of a prokaryotic cell. For example, blue, green algae and bacteria are constituted of this type of cell.
In this type of cell, the nucleus is well structured that means nuclear materials are well organised and surrounded by a nuclear membrane. Chromosomes are organised with DNA, histone protein, and other components. From algae to higher flowering plants and from Amoeba to advanced animals, the basic structural and functional component is eukaryotic type of cell. Along with ribosome, other cell organelles are present in the cell.
On the basis of function, there are two other types of cells: somatic cell and gametic cell.
This type of cell takes part in the organization of the body of an organism. The cell divides through the process of binary fission and mitotic division. Organisms grow in this way. Moreover, cells take part in the organization of different organs and organ systems.
Gametal cells are produced in the organisms in which sexual reproduction and alternation of generations occur. Primordial germ cells divide through meiotic division and produce gametic cells. In a gametic cell, a

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Retrieved Text: Prokaryotes such as bacteria propagate by binary fission. For unicellular organisms, cell division is the only method to produce new individuals. In both prokaryotic and eukaryotic cells, the outcome of cell reproduction is a pair of daughter cells that are genetically identical to the parent cell. In unicellular organisms, daughter cells are individuals.
To achieve the outcome of identical daughter cells, some steps are essential. The genomic DNA must be replicated and then allocated into the daughter cells; the cytoplasmic contents must also be divided to give both new cells the machinery to sustain life. In bacterial cells, the genome consists of a single, circular DNA chromosome; therefore, the process of cell division is simplified. Mitosis is unnecessary because there is no nucleus or multiple chromosomes. This type of cell division is called binary fission.
The cell division process of prokaryotes, called binary fission, is a less complicated and much quicker process than cell division in eukaryotes. Because of the speed of bacterial cell division, populations of bacteria can grow very rapidly. The single, circular DNA chromosome of bacteria is not enclosed in a nucleus, but instead occupies a specific location, the nucleoid, within the cell. As in eukaryotes, the DNA of the nucleoid is associated with proteins that aid in packaging the molecule into a compact size. The packing proteins of bacteria are, however, related to some of the proteins involved in the chromosome compaction of eukaryotes.
The starting point of replication, the origin, is close to the binding site of the chromosome to the plasma membrane (Figure

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Retrieved Text: Students use Second Life to look at a eukaryotic cell and create a PowerPoint presentation of their findings. In this cells lesson plan, students provide information on how cells survive.
In this cells worksheet, students review what is composed of cells and compare and contrast prokaryotic cells and eukaryotic cells. This worksheet has 7 fill in the blank and 3 short answer questions.
In this prokaryotic and eukaryotic cell learning exercise, students read the given passage and answer the provided questions. Students answer questions about what prompts replication and cell division.
Learners list and define all of the major organelles in a eukaryotic cell. They identify the correct placement of all the major organelles in a eukaryotic cell. They examine cell membrane and its function.

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Retrieved Text: is not attached to the retina.
How are prokaryotic and eukaryotic cells similar?
What is special about the cell nucleus?
It provides the cell's energy.
It contains nutrients we need.
prokaryotic because it contains a nucleus.
eukaryotic because it contains a nucleus.
prokaryotic because it contains ribosomes.
eukaryotic because it contains ribosomes.
Which statement is NOT true about the differences between liver cells and kidney cells in the same organism?
They contain the same genes, but express them differently.
What is the main purpose of the fruits of a plant?
Which of the following describes the reason why graphite is a strong electrical conductor?
Why is humus an important part of soil?
It contains nutrients, which feed the plants.
It contains rocks, which strengthen the soil.
It contains chemicals, which fight disease.
contains ribose instead of deoxyribose.
A liquid takes the shape of its and does not have its own .
Identify the correct definition of cookware.

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Retrieved Text: The cell nucleus acts like the brain of the cell. It helps control eating, movement, and reproduction. If it happens in a cell, chances are the nucleus knows about it. The nucleus is not always in the center of the cell. It will be a big dark spot somewhere in the middle of all of the cytoplasm (cytosol). You probably won't find it near the edge of a cell because that might be a dangerous place for the nucleus to be. If you don't remember, the cytoplasm is the fluid that fills cells.
Not all cells have a nucleus. Biology breaks cell types into eukaryotic (those with a defined nucleus) and prokaryotic (those with no defined nucleus). You may have heard of chromatin and DNA. You don't need a nucleus to have DNA. If you don't have a defined nucleus, your DNA is probably floating around the cell in a region called the nucleoid. A defined nucleus that holds the genetic code is an advanced feature in a cell.
The things that make a eukaryotic cell are a defined nucleus and other organelles. The nuclear envelope surrounds the nucleus and all of its contents. The nuclear envelope is a membrane similar to the cell membrane around the whole cell. There are pores and spaces for RNA and proteins to pass through while the nuclear envelope keeps all of the chromatin and nucleolus inside.
When the cell is in a resting state there is something called chromatin in the nucleus. Chromatin is made of DNA, RNA, and nuclear proteins. DNA

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Retrieved Text: Mitochondria were isolated from lymphoblasts derived from normal (squares) or TRMA individuals (circles) were incubated for 15 minutes with various concentrations of radioactive thiamine.
Mitochondria were isolated from normal (open squares) or TRMA (open circles) lymphoblasts and were incubated for 15 minutes with various concentrations of radioactive ThDP.
Uptake of thiamine and ThDP by mitochondria was determined by a rapid filtration procedure [26,28].
Mitochondria are membrane-enclosed organelles distributed through the cytosol of most eukaryotic cells.
This has strengthened the theory that mitochondria are the evolutionary descendants of a bacterium that established an endosymbiotic relationship with the ancestors of eukaryotic cells early in the history of life on earth.
Perhaps rickettsias are the closest living descendants of the endosymbionts that became the mitochondria of eukaryotes.
Mitochondria are responsible for converting nutrients into the energy-yielding molecule adenosine triphosphate (ATP) to fuel the cell's activities.
This function, known as aerobic respiration, is the reason mitochondria are frequently referred to as the powerhouse of the cell.
Mitochondria are unusual organelles in that they contain deoxyribonucleic acid (DNA), typically found in the cell’s nucleus, and ribosomes, protein-producing organelles abundant in the cytoplasm.
Mitochondria are able to modify their structure to meet the changing requirements of the cell.
Mitochondria may fuse or increase in size to form giant mitochondria or megamitochondria, and they are also able to divide in a sequence that morphologically resembles bacterial division.
Mitochondria tend to locate near the structures were the energy is required, as illustrated by the close association with rough endoplasmic reticulum in cells with high synthetic activity.
Mitochondria are sometimes described as "cellular power plants", because their

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Retrieved Text: and functions in the presence or absence of O2.
in the cytoplasmic matrix of procaryotes and eucaryotes.
The pathway as a whole may be divided into two parts.
will soon be used to make ATP.
energy is captured as a glucose molecule is converted to two molecules of pyruvate.
3). Inclusion Bodies: There are granules of organic or inorganic materials. These bodies are generally for storage( Eg carbon compound, inorganic substance & energy) & also helps to osmotic pressure. Some of the inclusion bodies are poly-beta- hydroxy butyrate granules( carbon storage), some glucose(carbon storage), sulphur granules( sulphur storage), gas vacuoles( helps bacteria to regulate buoyancy & float), phosphate granules or volutin granules or meta chromatin granules( storage of phosphates).
2.) Cytoplasm: It refers to internal matrix of cell inside the cytoplasmic membrane. Prokaryotic cytoplasm lacks membrane bound structures . The cytoplasmic matrix is largely watered which dissolves proteins, amino acids, sugars, nucleotides, salts, vitamins, & ions. It also contains certain bacterial structures like inclusion bodies, nucleoid, plasmids.
A) Ribosomes: They are r-RNA protein bodies which give granular appearance. Proteins are synthesized in ribosomes & prokaryotic. Proteins are synthesized in ribosomes & prokaryotic ribosomes aren't bound to endoplasmic reticulum. Ribosomes of prokaryotes are called 70S(Sedimentation Coefficient) & are composed of 2 units(50S & 30S). Antibiotics such as Streptomycin &Tetracycline prevents bacterial ribosomes from carrying out protein synthesis.
1) Cytoplasmic membrane: It is a thick structure( 8 nm) that separates the cytoplasm from outer membrane. It is composed of phospholipid & protein. Phospholipid forms the bi layer in which protein( integral & peripheral) are held.
It acts

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Retrieved Text: Hi y'all! So, I noticed while I was reading up and watching videos from the Amoeba Sisters (LOVE), Crash Course (LIKE), etc., that I had to go back and reread/re-watch crucial parts of the cell over and over again to really DRILL IT IN. I can't tell you how many times I had to go back and figure out what the hey a lysosome even is! I'll try to make it easier on you guys, because I had to do "Learn" on Quizlet to figure it out... Anyway, let's get going!
+ A eukaryotic cell has a nucleus that can contain DNA.
+ A eukaryotic cell has membrane-bound organelles.
+ A eukaryotic cell has a cell membrane & cytoskeleton.
The cell membrane: I made a whole blog about it, but basic outline, it has a hydrophilic head and a hydrophobic tail, and it acts as the gatekeeper to the cell.
The cytoplasm: It is the clear gel that surrounds the whole interior of the cell. It is sort of like the bubble wrap that wraps your whole Amazon order in bubbly "peace-of-mind-ful" comfort.
The cytoskeleton: It's only job is to make sure that the all-important cells don't exit the membrane into the environment around it, eventually causing cellular destruction! Mwa-ha-ha-ha-ha! Ahem. Yeah, so, without it, we're toast.
The mitochondria: These oblong organelles are the battery pack of the whole thing! If the cell were a city, these mitochondria would be the power lines. The purpose of the mitochondria is to make ATP, the money of the cell. See, Cell City here even has

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Retrieved Text: All cells share four common components: 1) a plasma membrane, an outer covering that separates the cell’s interior from its surrounding environment; 2) cytoplasm, consisting of a jelly-like cytosol within the cell in which other cellular components are found; 3) DNA, the genetic material of the cell; and 4) ribosomes, which synthesize proteins. However, prokaryotes differ from eukaryotic cells in several ways.
A prokaryote is a simple, mostly single-celled (unicellular) organism that lacks a nucleus, or any other membrane-bound organelle. We will shortly come to see that this is significantly different in eukaryotes. Prokaryotic DNA is found in a central part of the cell: the nucleoid ( [link] ).
Most prokaryotes have a peptidoglycan cell wall and many have a polysaccharide capsule ( [link] ). The cell wall acts as an extra layer of protection, helps the cell maintain its shape, and prevents dehydration. The capsule enables the cell to attach to surfaces in its environment. Some prokaryotes have flagella, pili, or fimbriae. Flagella are used for locomotion. Pili are used to exchange genetic material during a type of reproduction called conjugation. Fimbriae are used by bacteria to attach to a host cell.
The most effective action anyone can take to prevent the spread of contagious illnesses is to wash his or her hands. Why? Because microbes (organisms so tiny that they can only be seen with microscopes) are ubiquitous. They live on doorknobs, money, your hands, and many other surfaces. If someone sneezes into his hand and touches a doorknob, and afterwards you touch that same doorknob, the

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Retrieved Text: Karl August Möbius was the German zoologist who took the credit for the usage of a diminutive or organ. Organula was the tern used by this zoologist for the cellular structure.
The term organelle is considered similar with the cell compartment based on the opinion of most cell biologists.
The cell biologists who choose the specific definition of cell organelles state that a term can only be applied on those which contain DNA.
The organelles which contain DNA include plastids which can be found on some protists, algae and plants. Almost all eukaryotes contain mitochondria.
There are several organisms which have the organelles without DNA. It can be found on the flagellum.
The structure of Eukaryotic cells is very complex. The lipid membranes enclose the interior compartments of the cells.
You can use the light microscope to scrutinize the large organelles on the eukaryotic cells. You will be able to observe the vacuoles and nucleus. Mitochondria are considered as the common organelle that can be found in most eukaryotic cells.
If you compare the Eukaryotic cells and prokaryotic cells, the latter ones are less complex. In the past, people believe that the internal organization of the prokaryotic cells was little. Find facts about cell wall here.
It is stated that some prokaryotes have the micro compartments based on the current research about this cell. The diameter of the compartment is around 100–200 nm. The shell of protein is seen as the enclosure of this sub cellular compartment. Get facts about cell membrane here.
Based on the report in 2006, bacteria have the membrane-bound magnetosomes. In

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Retrieved Text: Why are vessel elements better than tracheids?
What is requird for a plant to hold its cell together?
Events occurring during the G1, S, and G2 stages of interphase.
Importance of plasmodesmata to living plant cells?
Ultrastructure of a prokaryotic cell.
Difference between a prokaryotic cell and a eukaryotic cell?
Similarities between plant cells and animal cells?
Difference between protoplasm and cytoplasm?
Functions of plasmodesmata in a plant cell?
Functions of cytoskeleton in plant cells?
Function of microbodies in plant cell.
Functions of mitochondria in plant cell.
Functions of chromoplast in plant cell.
Function of leucoplasts in a plant cell?

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Retrieved Text: Dogs and cats, butterflies and crayfish, lizards and birds, poison ivy and rosebushes and strawberry plants are all organisms. Organisms are composed of organ systems (digestive, circulatory or immune systems, to mention three examples). These systems are in turn composed of organs, which are composed of tissues which are composed of cells. The cell is where the action is!
The definition of life usually includes the requirement that whatever lives is capable of viable reproduction, which makes it subject to evolution. All life is composed of cells and they reproduce.
Eukaryotic contain structures called organelles, many of which are not found in prokaryotic cells. One such organelle is the nucleus, which houses the DNA.
Prokaryotic cells are usually smaller. They do not contain nuclei, so their DNA is floating around in the cytoplasm. They do contain ribosomes to carry out protein synthesis.
Cells come in a huge variety of shapes and functions. They are the basis of all living beings. Whether they are nerve cells, muscle cells, skin cells, bone cells or any other kind of cells; whether they come from humans or cats or grasshoppers or oak trees or bacteria, they all are based on common features like a membrane filled with cytoplasm, DNA or RNA along with ribosomes for reproduction, and the fabrication by cellular respiration of ATP for energy. This fact seems to represent a certain indication of the common origin of all life.
As we saw in the discussion of water, lipid bilayers, in this case, phospholipid bilayers, can form membranes. All cells are surrounded and protected

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Retrieved Text: Molecular Biology and Applied Genetics 1 CHAPTER ONE THE CELL Specific learning objectives ⇒ Identify an eukaryotic and prokaryotic cell ⇒ Describe chemical composition of the cell membrane ⇒ List the structure found in a membrane ⇒ Describe the role of each component found in cell membrane 1.0. Eukaryotic and Prokaryotic Cell Cells in our world come in two basic types, prokaryotic and... principles of animal biology Download principles of animal biology or read online here in PDF or EPUB. Please click button to get principles of animal biology book now.
Description of the book "Principles of Animal Biology": Unlike some other reproductions of classic texts (1) We have not used OCR(Optical Character Recognition), as this leads to bad quality books with introduced typos.

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Retrieved Text: Prokaryotes were the first kind of organisms to evolve. They are single-celled organisms that don’t have a well-defined nucleus and also lack other membrane-bound organelles such as mitochondria. The genetic material in prokaryotic cells exists within an irregularly shaped area of the cell known as the nucleoid.
All water-soluble components within prokaryotes such as DNA, proteins and metabolites are found in the cytoplasm, enclosed within the cell membrane and not in separate compartments of the cell. However, bacteria have protein-based micro-compartments that behave like basic organelles within protein shells.
The two types of prokaryotic cell are Archaea and bacteria. Prokaryotes have a cytoplasm, plasma membrane, DNA, and ribosomes, but no nucleus. They have a cell wall that offers an additional layer of protection, prevents dehydration and maintains the shape of the cell. The cell wall is made of peptidoglycan. Some prokaryotic cells also have a polysaccharide layer, referred to as a capsule, that enables specific attachment of the cell to certain surfaces.
Prokaryotes have a plasma membrane, which separates intracellular components from the external environment. Prokaryotic cytoplasm is made up of a jelly-like substance called the cytosol, in which cell components are contained.
As is the case for all cells, bacteria have a cytoskeleton, a network of filaments and tubules that provides structural support and maintains the shape of the cell. The cytoskeleton also forms a whip-like, external structure called the flagella, which the cell uses to move from one place to another (locomotion). Thin, hair- like structures called pili are also found in some bacteria, which aid in adhesion

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Retrieved Text: Where did cells come from?
A eukaryotic cell is a complex structure that includes nucleic acids, which hold information, as well as proteins, sugars and fats. But how did something as complex as this evolve? Barry Gibb explains how the right molecules combined with protective membranes eventually led to the cells that make up all of us.
If the universe originated with the Big Bang, life on Earth started with more of a whisper. There are different ideas about how life got going: did that first glimmer of life originate from colliding meteorites, thermal vents in the young oceans or the fabled ‘primordial soup’ – a handy cocktail of organic molecules?
What is certain is that, at some point in evolution, larger organic molecules – such as nucleic acids and amino acids – began to form, aided by the volatile climate of the time. Scientists can only speculate on how many different combinations of molecules were rejected by natural selection before molecules that had the qualities needed to persist evolved.
What we now know about ribonucleic acid (RNA) makes it a strong contender for possibly being the first life on Earth. We tend to think of RNA as the industrious go-between that links DNA and proteins, but RNA is special. Its ability to act as a self-replicating molecule and perform catalytic reactions (like enzymes) makes it a biological Swiss army knife, showing the sort of self-sufficiency needed in an ambitious molecule.
Next in the evolution of the cell came the involvement of a protective barrier, something that could protect the delicate

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Input Text: Answer the following question given this paragraph: 

17.8 Gonadal and Placental Hormones The male and female reproductive system is regulated by follicle-stimulating hormone (FSH) and luteinizing hormone (LH) produced by the anterior lobe of the pituitary gland in response to gonadotropin-releasing hormone (GnRH) from the hypothalamus. In males, FSH stimulates sperm maturation, which is inhibited by the hormone inhibin. The steroid hormone testosterone, a type of androgen, is released in response to LH and is responsible for the maturation and maintenance of the male reproductive system, as well as the development of male secondary sex characteristics. In females, FSH promotes egg maturation and LH signals the secretion of the female sex hormones, the estrogens and progesterone. Both of these hormones are important in the development and maintenance of the female reproductive system, as well as maintaining pregnancy. The placenta develops during early pregnancy, and secretes several hormones important for maintaining the pregnancy.


Q: The male and female reproductive system is regulated by follicle-stimulating hormone (fsh) and luteinizing hormone (lh) produced by what gland?

 Choices:

- pituitary

- adrenal

- thyroid

- testes

A:

Target Text: pituitary

#### Retrieved Documents ####

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Retrieved Text: Follicle Stimulating Hormone (FSH) - is produced by the pituitary gland and is responsible for the egg maturation process. High day 3 FSH levels are associated with diminished ovarian reserve. The cycle day 3 CD 3 hormonal testing for fertility and infertility is referred to as "day 3 blood work."
Starting the female fertility evaluation can feel overwhelming and cycle day 3 hormone testing is usually the very first test done in a woman.
Hormone testing is generally performed on menstrual cycle day (CD) 3 (or 2 or 4) and is done by a simple blood test. CD 1 refers to the first day of full flow menstrual bleeding and not spotting.
The hormonal testing is referred to as "cycle day 3 (CD3) blood work."
Follicle Stimulating Hormone (FSH) - is produced by the pituitary gland and is responsible for the egg maturation process. High day 3 FSH levels are associated with diminished ovarian reserve.
Estradiol (E2) - is produced by the ovary and levels should be low in the early part of the menstrual cycle. High day 3 levels may indicate a cyst in the ovary or diminished ovarian reserve.
Luteinizing Hormone (LH) - is produced by the pituitary gland and levels are increased before ovulation. A LH/FSH ratio of greater than 2:1 or 3:1 may be diagnostic of Polycystic Ovarian Syndrome (PCOS).
Prolactin - Both luteinizing hormone (LH) and follicle-stimulating hormone (FSH) are necessary for ovulation. If, for example, hyperlactinemia is caused by a prolactionoma, a tumor in the pituitary gland, then this could interfere with the secretion of LH and

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Retrieved Text: The basic components of the female reproductive system are the hypothalamus, the pituitary, and the ovary. The hypothalamus, located at the base of the brain, is ''grand central station,'' where internal and external signals are translated into chemical messages, called releasing or inhibiting factors. The key releasing factor for reproduction is gonadotropin-releasing hormone (GnRH), which when released in defined pulses causes the secretion of luteinizing hormone (LH) and in some cases follicle-stimulating hormone (FSH) by the anterior pituitary gland. A key inhibiting factor is dopamine, which inhibits the secretion of prolactin by the anterior pituitary gland.

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Retrieved Text: Gonadotropins, also known as gonadotrophins, are hormones secreted by the pituitary gland. The gonadotropin-releasing hormone or GnRH pulses stimulate the pituitary gland so that it begins the production of gonadotropins.
Gonadotropins are produced by men and women and they regulate the reproductive cycle in both cases. However, men and women do not have the same levels of gonadotropins, and of course the actions regulated are different in each case.
These hormones are used as medicines in assisted reproductive treatments for women such as ovulation induction, allowing them to have greater chances for pregnancy.
There are three types of gonadotropic hormones: FSH, LH, and hCG. They are all involved in women’s ovarian cycle, although each one acts in a different stage of the cycle and has a different function.
The FSH (follicle-stimulating hormone) is most abundant during the first half of the menstrual cycle, since it is responsible for the growth of the follicles within the ovary.
For the assisted reproductive treatments, the FSH is usually prescribed for ovulation induction treatments with the aim of increasing the growing follicles and stimulating their development.
The LH (luteinizing hormone) is responsible for the ovulation process in women. A spike in the amount of LH may trigger ovum releasing from the antral follicle in order to release an egg into the Fallopian tubes.
This hormone is used during ovulation induction in order to maximise the conditions given during natural ovulation.
hCG causes final maturation of the eggs and is a pregnancy specific hormone in every pregnant woman, since it is essential to placental development, among other functions.
hCG may

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Retrieved Text: FSH – Follicle-stimulating hormone is produced by the pituitary gland and regulates the development, growth and reproductive processes in the body. In women, FSH helps regulate the menstrual cycle and production of eggs by the ovaries. In men, it helps control the sperm production. An abnormally high or low level of FSH in the body can be a sign of the body’s inability to produce eggs or sperm.
LH – Luteinizing hormone is produced by the anterior pituitary gland and works synergistically with the follicle-stimulating hormone. LH plays a major role in regulating menstrual cycle and egg production in women, as well as stimulating the production of testosterone (a hormone which stimulates sperm production) in men. Abnormally high levels of LH may be a sign of premature menopause or polycystic ovary syndrome (in women) and testicular failure (in men).
Progesterone – also known as P4, this is a steroid hormone involved in pregnancy and embryogenesis. It is produced in the ovaries during the second half of the menstrual cycle and helps prepare the uterus for pregnancy. Progesterone levels remain elevated during pregnancy and help the placenta function properly. A progesterone test is aimed at determining whether ovulation is occurring.
Prolactin – this is a hormone, produced by the pituitary gland that is best known for its role in lactation. Pregnant women with high prolactin levels will have breast milk, but high levels of prolactin in women who are not pregnant or are not breastfeeding may cause difficulties in conceiving as it inhibits ovulation.
Testosterone – this male hormone affects the

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Retrieved Text: The gonadotropins are peptide hormones that regulate ovarian and testicular function and are essential for normal growth, sexual development and reproduction. The human gonadotropins include follicle stimulating hormone and luteinizing hormone which are made in the pituitary, and chorionic gonadotropin which is made by the placenta.
Follicle stimulating hormone (FSH) is a pituitary hormone that regulates growth, sexual development and reproduction, including menstruation, follicular development and ovulation.
Luteinizing hormone (LH) is a pituitary hormone that is essential for sexual development and reproduction in both men and women.
Prolactin is a hormone produced by the pituitary gland that causes breast development in women and milk production in pregnant women. Prolactin does not have known biological function in men.

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Retrieved Text: Female hormonal testing is recommended when irregularities are identified in your menstrual cycle or physical examination. We offer various hormonal tests at our Beverly Hills, Valencia, and Sherman Oaks offices, including estrogen and progesterone levels, FSH and LH levels, Inhibin B, Anti Mullerian Hormone (AMH), Testosterone and other androgens, thyroid tests, and Prolactin levels. The results of these hormonal tests help determine the best course of treatment for each individual patient.
AMH is a hormone produced by the ovary, that reflects ovarian reserve and recruitable eggs available for fertility in a cycle. It is not affected by the time of the cycle and minimally affected by the use of oral contraceptives. An individual desiring to evaluate their fertility potential should have a serum AMH level tested. High AMH levels are seen in young females with great ovarian reserve or patients with PCOS.
Inhibin B is a hormone produced by the ovary that can be tested on day 1, 2 or 3 of the menstrual cycle. It has been shown to reflect ovarian reserve/ egg quality. Levels can fluctuate in a cycle and in between cycles. Inhibin B is suppressed by oral contraceptives. Its use is not universally accepted by by all fertility specialists.
Estrogen is largely responsible for stimulating the development of the endometrium, the blood-rich mucus membrane that lines the uterus. There are three forms of estrogen found in the human body: estrone, estradiol (E2), and estriol. Low levels of estradiol may indicate that the follicles (small sacs in the ovaries) do not contain healthy eggs. Because estrogen

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Retrieved Text: FSH or follicle stimulating hormone is a hormone that signals the ovarian follicles in your ovaries to stimulate the growth of immature eggs or ova. This hormone rise signals the start of a new ovulation cycle.
Follicle stimulating hormone levels start to rise near the end of your last ovulation cycle just before your menstrual period begins.
At this time, progesterone levels drop as a result of the corpus luteum degenerating because fertilization or implantation of the egg (ovum) did not take take place during your last ovulation cycle. Because of this drop, your uterus begins to shed the endometrium (lining) and you get your period.
FSH hormone levels will continue to rise throughout your menstruation period.
This hormone is a gonadotropin hormone that is made and released from your pituitary gland.
Follicle stimulating hormone, as it relates to your menstrual cycle, is controlled by pulses of gonadotropin-releasing hormone (GnRH) from your hypothalamus.
As your eggs (ova) mature, they release estrogen, or more correctly, estradial (one type of estrogen).
As estradial builds and begins to peak, this signals the hypothalamus to slow production of gonadotropin-releasing hormone (GnRH).
This then signals the pituitary gland to slow production of the follicle hormone.
Before this drop in follicle-stimulating hormone, your eggs (ova) have been competing to be the dominant one.
This drop ensures that (usually) only one follicle, that contains one egg (ovum), will reach dominance and be released at ovulation. Of course, if two reach dominance, you get (fraternal) twins. And so on.
What this action does is ensure the best, strongest, and healthiest egg (ovum) of the bunch,

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Retrieved Text: The pituitary gland is divided into two main parts, the anterior and posterior lobes. The anterior pituitary consists of endocrine cells that synthesize and secrete hormones directly into the blood. The posterior pituitary is an extension of the hypothalamus. It stores and secretes two hormones that are made by a set of neurosecretory cells in the hypothalamus.
The posterior pituitary releases the hormones oxytocin—which acts on muscles of the uterus—and antidiuretic hormone (ADH), which acts on the kidneys. Oxytocin induces contraction of the uterine muscles during childbirth and causes mammary glands to eject milk during nursing. ADH acts on the kidneys, increasing water retention and thus decreasing urine volume.
The anterior pituitary produces six different hormones. Growth hormone affects a wide variety of tissues. The correct level of growth hormone production is essential, as too little or too much can have serious detrimental effects. Prolactin stimulates mammary gland growth and milk synthesis. Follicle stimulating hormone (FSH) stimulates production of ova and sperm, and luteinizing hormone (LH) stimulates the ovaries and testes. LH is needed for ovulation and the formation of a corpus luteum in the female menstrual cycle. LH also stimulates the testes to produce testosterone. FSH and LH are referred to as gonadotropins because they stimulate the activities of the gonads. Thyroid-stimulating hormone, stimulates the thyroid gland to produce thyroxine. Adenocorticotropic hormone influences the adrenal cortex to produce and secrete steroid hormones.
SEER Training Modules: Pituitary and Pineal Glands. Illustration courtesy of the National Cancer Institute, NIH.

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Retrieved Text: Clomid is a medication that works on a woman's estrogen receptors and hormones and thereby causes her body to ovulate more efficiently and regularly. The effects of Clomid begin in the hypothalamus, a small gland at the base of the brain. There, Clomid causes the production of gonadotropin-releasing hormone. The GnRH prompts the brain's pituitary gland to produce more follicle-stimulating hormone and luteinizing hormone. The newly produced FSH and LH stimulate the ovaries into producing more follicles and eggs. In a nutshell, Clomid tricks a woman's body into secreting more ovulation-causing hormones and ultimately results in improved ovulation.

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Retrieved Text: Injectable fertility drugs such as Follistim, Gonal-F. Menopur and Bravelle are very effective at inducting ovulation and treating infertility.
These fertility medications contain a hormone called follicle stimulating hormone (FSH) that is normally produced by the pituitary gland which is located at the base of the brain. The FSH can be made in the lab using recombinant DNA technology (Follistim and Gonal-F) or extracted from urine (Bravelle).
FSH stimulates the eggs to grow and when given in higher doses can overcome the body's normal mechanisms that prevent the release of more than one egg which can in turn lead to multiple births. Because of the chemical structure of FSH, it will not work when taken by mouth, so it always must be given by injection. Some formulations such as Follistim and Gonal F are given by a specially designed pen and others such as Bravelle have to be reconstituted from a powder and given with a syringe.
Human menopausal gonadotropins are another type of injectable fertility medication which contain not only FSH, but another pituitary hormone called LH (luteinizing hormone), or at least a hormones that function like LH. Like Bravelle it is extracted from urine and must be reconstituted fresh from a powder each day. HMG is often used with or instead of FSH in women with polycystic ovarian syndrome (PCOS) or undergoing in vitro fertilization (IVF). The side effects of menopur are the same as those of FSH.
hCG is the hormone produced by pregnant women that we measure in a pregnancy test. Because hCG works in a

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Rank: 10
Score: 99.88781
Retrieved Text: Monster Plexx® by Innovative Labs is one of the few legal pro hormone complexes that can actually give you intense gains in strength and size that you are looking for. Monster Plexx consists of 5 Pro-hormones combined at high level milligrams (250 total milligrams) making it the first ever “Quintuple stack”.
Experience a snowball effect of muscular development when your hormone levels are consistently peaking due to the combination of quick acting and long lasting anabolic agents – no need to worry about timing your doses.
Diosterol®: Stimulates the hypothalamus secretion of luteinizing hormone (LH), but not of follicle stimulating hormone (FSH). The mechanism of Diosterol’s® action causes increases the production of serum testosterone. Most of all, steroidal saponins have been identified as the bioactive constituents responsible for the anabolic effects, these saponins enable the body to produce more testosterone by raising the levels of the Luteinizing Hormone (LH), which a hormone released normally by the pituitary gland helps to maintain testosterone production. As the LH increases, so testosterone increases.

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Rank: 11
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Retrieved Text: This NCLEX review will discuss the female reproductive cycle (menstrual cycle). In maternity nursing, you will learn the menstrual cycle.
As a nursing student, you must be familiar with each phase, what occurs during the phase, the role of the hormones, and what happens if pregnancy occurs. These type of questions may be found on NCLEX and definitely on nursing lecture exams in maternity.
After you review these notes on the menstrual cycle, don’t forget to take the menstrual cycle quiz.
Purpose of the Menstrual Cycle: is to release an egg for potential fertilization (from the ovary) so it can implant into the endometrium…hence help develop a baby. If this doesn’t happen, the 28 day cycle starts all over (note cycle days vary among women).
Woman has bleeding (consists of 1-6 days) where she is shedding the stratum functionalis (functional layer) of the endometrium. If pregnancy did not occur during the last cycle, the progesterone and estrogen levels drop which causes the layer to shed.
How does it do this? When hormone levels from the previous cycle drop (specifically progesterone and estrogen) the hypothalamus releases Gonadotropin-Releasing Hormone (GnRH) and this causes the anterior pituitary gland to release FSH (follicle stimulating hormone) and LH (luteinizing hormone).
The FSH released from the anterior pituitary gland stimulates the follicles in the ovary to grow. A woman has two ovaries (right and left) and each contains MANY follicles.
Follicles are fluid-filled sacs in the ovary that contain an immature egg known as an oocyte. NOTE: FSH will cause several follicles to develop but only ONE turns into

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Rank: 12
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Retrieved Text: Clomiphene citrate pills is the medication of choice to stimulate ovulation and thus optimize your chances of conceiving. Clomid for short. It targets the pituitary gland and determines it to produce and release more follicle-stimulating hormones (FSH), leading to the growth of estrogen-secreting ovarian follicles and the release of the luteinizing hormone (LH). Thus, the ovulatory phase of the menstrual cycle begins, and this is the optimum moment to try to conceive. 36 hours later, ovulation occurs when the dominant ovarian follicle releases its fully matured egg.
Often, the doctor will adjust the initial dosage of Clomid. This drug is usually prescribed for at least three consecutive menstrual cycles. It is well-tolerated, it has mild side-effects and shows results in 80% of the treated women. However, note that women suffering from ovulation problems arising from hypothalamic disorders and extremely low estrogen levels do not respond well to Clomid.
Gonadotropin injections are usually prescribed for women suffering from lack of ovulation and who did not respond to the clomiphene treatment. This medication determines the stimulation of FSH and LH, to result in the development of a fully matured ovarian follicle, accompanied by a proper estrogen level. At this point, the ovulation is induced with the aid of Human chorionic gonadotropin. Typically, ovulation takes place about 36 hours after this injection.
Follicle-stimulating hormone, luteinizing hormone and human menopausal gonadotropin injections are synthetic hormones that mimic the presence of the natural ones. They balance the estrogen levels and help to induce ovulation in women who rarely or never ovulate.
Bromocriptine and Cabergoline pills

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Retrieved Text: For many couples, conceiving and carrying a pregnancy to term is not a problem while for others conception is challenging and elusive. Such couples may find themselves on the road to fertility treatments in order to bring about their desire for offspring.
If, after testing, the problem is shown to be ovulatory dysfunction, then it is likely the physician will prescribe Clomid, one of the most common fertility medications used to regulate or induce ovulation. Clomid is short for clomiphene citrate and, when initially prescribed, it is usually given at the lowest possible dose to see how or if it will work. If it fails to stimulate ovulation, the dose may be increased for the next cycle. It is suggested that Clomid be used for a maximum of six cycles and, if ovulation occurs with use, then there is no value in increasing the dosage. If there is no ovulation after six cycles, then other treatment should be considered.
To understand how Clomid works it is of value to know what happens during a normal ovulatory cycle. The hypothalamus, a small gland at the base of the brain, works to regulate the levels of certain hormones produced by the pituitary gland which are necessary for normal reproductive organ function. Two of these hormones which are affected (and vitally necessary for reproduction) are follicle stimulating hormone (FSH) and luteinizing hormone (LH).
FSH production is stimulated by gonadotropin releasing hormone (GnRH), which is produced by the hypothalamus. FSH is the hormone which causes the growth and development of ovarian follicles -

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Rank: 14
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Retrieved Text: The amount of information available on Vitex or Chastetree berry (Vitex agnus castus) is so much so that many women come to us confused, concerned and/or interested in its proper use. Below are common questions we receive about the benefits Vitex offers and its proper use.
A: Typically, we suggest starting to support the body naturally after stopping birth control by doing a Fertility Cleanse. Cleansing helps “clean the slate” and detoxify excess hormones and toxins in order to help the body better utilize herbs, nutritional supplements, and natural therapies. When cleansing is complete, herbs that support hormonal balance like Vitex could be started. It is easily combined with other herbs, nutritional supplements, and natural therapies as shared in our guide How to Balance Your Hormones After Birth Control.
A: Vitex has a nourishing and balancing effect on the pituitary, hypothalamus and organs of the endocrine system. This, in turn, helps to balance the delicate hormonal system, which then causes FSH, LH, Progesterone, Testosterone, etc. to be secreted in proper amounts at the correct times.
FSH is only partially responsible for the production of the ova (eggs).
Vitex is known to encourage luteinizing hormone (LH) production while mildly inhibiting the release of follicle stimulating hormone (FSH) when needed. This indirectly boosts progesterone production which is necessary for a healthy endometrial lining in the luteal phase in order to achieve and maintain pregnancy. This is why it is taken before ovulation.
Our site’s founder Hethir Rodriguez, through her research and use of Vitex with clients, has learned that Vitex is best taken

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Rank: 15
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Retrieved Text: Our Factrel coupons, rebates, and discounts will help you save. Never pay full price on your prescriptions again.
Factrel is grouped in a class of drugs known as gonadotropin-releasing hormones. Gonadotropin is one of the most important hormones in the reproductive part of the female body. Its purpose is to control the ovulation and menstruation. The drug is used to stimulate the pituitary gland to release other reproductive hormones. Factrel is only used on cattle.
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Factrel is used to cause ovulation in women who suffers from irregular ovulation and menstrual periods. The problem is caused by having a faulty hypothalamus gland that is responsible for releasing gonadotropin releasing hormone. Factrel functions by stimulating the pituitary gland to release other reproductive hormones like luteinizing hormone (LH) and follicle-stimulating hormone (FSH) that controls the development of calves and the fertility of cows. The drug is used to the test how well the hypothalamus and the pituitary gland are working. Factrel is also used in the medication of other conditions but under the prescription of a qualified

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Rank: 16
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Retrieved Text: The exact cause of polycystic ovarian syndrome (PCOS) is still not known for sure. But numerous factors play a role in the manifestation of PCOS. The effect of PCOS on ovaries and their production of estrogens, progesterone and testosterone hormones, and the resulting hormonal imbalance have a huge impact on all our body systems. It is essential that PCOS be treated due to the far-reaching impact on women healthcare issues other than possible infertility.
PCOS affects the reproductive system most, but it is essentially an endocrine-system related disorder. Researchers are of the opinion that there is a link between insulin level and PCOS occurrence as women with PCOS are known to have insulin resistance. It is claimed that high androgen (testosterone) and luteinizing hormone levels cause PCOS. Research is on to probe the role of genetics and gene mutation in PCOS.
Genetics: A woman with a mother or sister with PCOS has a higher chance of getting PCOS. You can inherit PCOS from either your paternal or maternal family.
Insulin resistance: Women with PCOS are not able to use up the insulin and excess insulin triggers excess androgen release.
Hormonal imbalance/deficiency:chronic anovulation because of continuous high estrogen levels>results in elevation of LH (leutinising hormone)and suppression of FSH(follicle stimulating hormone) leading to the characteristic LH/FSH ratio of 2 or more >this altered ratio prevents follicle development and promotes stromal hyperplasia>ovaries therefore produces excess male hormone(androstenedione)>which results in the signs of hyperandrogenism.
One of the main causes for PCOS is the hormonal imbalance. The ovaries make a nominal amount of androgen generally. But

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Rank: 17
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Retrieved Text: Retrieved 17 January Obtain baseline hematocrit and lipid profile and monitor at follow-up visits. Archives d'anatomie et de cytologie pathologiques. In both sexes, the hypothalamus produces gonadotropin-releasing hormone GnRH to stimulate the pituitary gland to produce luteinizing hormone LH and follicle-stimulating hormone FSH. Access this article for 1 day for: PR agonists Progesterone derivatives: The Journal of Adolescent Health.
A patient's metabolic rate may change, causing an increase or decrease in weight and energy levels, changes to sleep patterns, and temperature sensitivity. Progesterone Quingestrone Retroprogesterone derivatives: It would bug me. Because feminizing hormone therapy might reduce your fertility, you'll need to make decisions about future childbearing before starting treatment.

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Rank: 18
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Retrieved Text: Luteinizing hormone (LH) and follicle-stimulating hormone (FSH) are found in hypogonadism, anorchia, gonadal failure, complete testicular feminization syndrome, menopause, Klinefelter syndrome, alcoholism, and castration. FSH and LH are pituitary products, useful to distinguish primary gonadal failure from secondary causes of gonadal failure, menstrual disturbances, and amenorrhea. It is useful in defining menstrual cycle phases in infertility evaluation of woman and testicular dysfunction in men. FSH is commonly used with LH. both FSH and LH are low in pituitary or hypothalamic failure and are high following menopause. Secretion of both LH and FSH are pulsatile, in response to the normal intermittent release of gonadotropin releasing hormone (GnRH). In addition, in females both FSH and LH vary over the course of the menstrual cycle, with peaks at time of ovulation. Thus, interpretation of a single determination may be difficult.

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Rank: 19
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Retrieved Text: The hypothalamus produces many neurosecretions that are released next to the primary capillary plexus at the median eminence. These hormones enter the long portal system and are carried to their target cells in the adenohypophysis. These hormones can either stimulate or inhibit the release of other hormones from the pituitary gland. The names and actions of the principal hypothalamic releasing and inhibiting hormones are listed below.
This hormone stimulates the release of Thyrotrophin and Prolactin from the Adenohypophysis.
This hormone stimulates the release of Luteinizing hormone (LH) and Follicle-stimulating hormone (FSH) from the Adenohypophysis.
This hormone stimulates the release of Corticotrophin from the Adenohypophysis.
This hormone stimulates the release of Somatotrophin (Growth Hormone) from the Adenohypophysis.
This hormone inhibits the release of Thyrotrophin and Somatotrophin from the Adenohypophysis.
This hormone inhibits the release of Prolactin from the Adenohypophysis.
There are many other substances released into the primary capillary plexus from the neurones including natriuretic peptide, angiotensin II and enkephalins. The precise role of these substances is still to be fully understood, but it is most likely to be regulatory.

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Retrieved Text: EIAgen FSH is a direct solid phase enzyme for the quantitative determination of Follicle-Stimulating Hormon (FSH) in human serum.
Follicle Stimulating hormone (FSH) is a glycoprotein consisting of two subunits with an approximate molecular mass of 35,500 daltons. The α-subunit is similar to other pituitary hormones [luteinizing stimulating hormone (LH), thyroid stimulating hormone (TSH) and chorionic gonadotropin (CG)] while the b-subunit is unique.
The b- subunit confers the biological activity to the molecule. Stimulation by gonadotropin-releasing hormone (GnRH) causes release of FSH, as well as LH, from the pituitary and is transported by the blood to their sites of action, the testes or ovary.
In men, FSH acts on the Sertoli cells of the testis, stimulating the synthesis of inhibin, which appears to specifically inhibit further FSH secretion, and androgen-binding protein. Thus, it indirectly supports spermatogenesis.
In women, FSH acts on the granulosa cells of the ovary, stimulating steroidogensis. All ovulatory menstrual cycles have a characteristic pattern of FSH, as well as LH, secretion. The menstrual cycle is divided into a follicular phase and a luteal phase by the midcycle surge of the gonadotropins (LH and FSH). As the follicular phase progresses, FSH concentration decreases. Near the time ovulation occur, about midcycle, FSH peaks (lesser in magnitude than LH) to its highest level.
The clinical usefulness of the measurement of Follicle Stimulating hormone (FSH) in ascertaining the homeostasis of fertility regulation via the hypothalamic - pituitary - gonadal axis has been well established (1,2).
In this method, calibrators, patient specimens and/or controls (containing the native FSH antigen) are first added to streptavidin

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Retrieved Text: There is no secret that today the in vitro fertilization intervention is the most effective in lab method that can give families with no children the chance to become parents and have kids. If we should talk about the factors that can cause infertility both in men and women then you should know that the list can be endless starting with a wrong diet, smoking and alcohol abuse and ending with physical disorders associated to different tumors, cancers or hypophysis malfunction.
If you don’t know pretty much about the way the pituitary gland affects your fertility you should stick around for a couple of minutes in order to read more about its role in the reproductive system functioning.
The first thing you should hear about is that the pituitary gland is located at the base of your brain and it has a pea dimensioned aspect. But regardless its size, this gland has a major endocrine role. You should know it performs many roles in secreting the growth hormone, the thyroid stimulating hormone, the luteinizing hormone and very important the follicle stimulating hormones.
You should know that secreting the follicle stimulating hormones the hypophysis has a very important role in ensuring a female fertility. Not to mention that the ovulation process is directly tied to the activity of these hormones. The follicle stimulating hormones are necessary for the ovarian follicle maturation. The reproductive process is regulated by these hormones and in many cases associated to infertility when the cause can be found in the lack of secreting these hormones. You

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Retrieved Text: Acupuncture and Chinese herbal medicine can improve a woman’s chances of conception through regulating the hormones, increasing the body’s basal temperature, thickening the lining of the uterus, and bringing on ovulation.
Research and clinical observation has shown that Acupuncture and Chinese herbal medicine are able to increase the body’s progesterone level and regulate the levels of FSH (follicle stimulating hormone),Estrogen (which increases as the follicle grows), and LH (the luteinizing hormone, which, in women, heralds the imminent release of the egg).
Chinese Medicine considers that a proper balance of these hormones is the key to a woman’s ability to conceive. Acupuncture and Chinese herbal medicine have been found to assist in establishing and maintaining a balance of both the reproductive and stress hormones, leading to a healthier menstrual cycle and a subsequent increase in the chances of falling pregnant.
Recent research tells us that, in Australia, one in twenty men is infertile, meaning that male infertility is implicated in one in five cases where a couple is having problems conceiving. The most common cause of male infertility is problems with sperm production, with one in 25 males suffering from a low sperm count.
Acupuncture and Chinese herbal medicine can increase the sperm count and improve the sperm’s motility and morphology. While sperm quality issues can often improve after 3 months of Acupuncture and Chinese medicine treatment, sometimes it may take longer depending on the severity of the problem. Infertility Acupuncture and Chinese herbal medicine also strengthen the internal organs, such as the kidneys, liver and spleen, adding to the overall

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Rank: 23
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Retrieved Text: Fifty percent of infertility problems arise due to female fertility issues. The exact underlying female fertility problem is difficult to identify. But usually, the problem diagnoses when difficulty arises to conceive. The irregularity of menstrual cycle, prolong menstruation or shortening of menstruation are some symptoms may be associated with female fertility problems. But it is not necessary the symptoms are the same for every fertility problem.
Ovulation disorder is common among 1 in 4 infertile couple. Ovulation disorder can be associated with infrequent ovulation and complete cessation of ovulation. This problem usually occurs due to endocrinal disorder arises in the reproductive system, or pituitary gland or hypothalamus. Ovarian ailments are also responsible for ovulation disorders.
Polycystic ovary syndrome (PCOS). Hormonal imbalance is the major underlying cause of PCOS. Obesity and insulin resistance are usually associated with PCOS. In addition, facial hair growth, acne formation are other symptoms of PCOS. This disorder is the most frequently affects female infertility.
Hypothalamic dysfunction. Follicle stimulating hormone (FSH) and luteinizing hormone (LH) are two pituitary hormones responsible for stimulating ovulation every month. There are certain factors like stress burden, abrupt increase or decrease BMI alter these hormones productions and affect ovulation. Irregular menstrual cycle or period missed are common clinical symptoms of this disorder.
Primary ovarian insufficiency/Premature ovarian failure. This is usually a response of autoimmunity or premature eggs loss in the ovary due to chemotherapy or genetic reason. Estrogen production diminishes before 40 years of age and eggs are no longer produced in the ovary.
Hyperprolactinemia: This is a condition in which excessive prolactin

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Retrieved Text: FSH or follicle-stimulating hormone is one of the hormones instrumental in helping to control and regulate the menstrual cycle and is also partially responsible for the production of the ova (eggs) in the ovaries. It is an indicator of a lot of things having to do with fertility. To learn all the details about the role of FSH in female and male fertility, go to our guide FSH Levels and Your Fertility.
For women, it’s important to know that FSH levels differ throughout the menstrual cycle, just as any other hormone of the monthly cycle. Doctors believe levels over 10 – 15 IU/L (international units per liter) may be high, depending on where you are in your cycle and where you get testing done. As women get older and enter their 40s, it is natural for FSH to get higher. That is one of the indicators of the natural “change of life” and that hormonal shifts are happening. Men can also have low/high FSH.
missing period or no ovulation (anovulation).
If you have low FSH, this may be an indicator of possible issues with the pituitary gland or hypothalamus.
Some people reach out to us really stressed because their FSH is a specific number and they want to get it down. While it is helpful to know where your levels are and it tells us a lot, it is one part of a big orchestra and it is not everything. Not all is lost, there is a lot we can do with this information!
The tips I talk about are going

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Retrieved Text: Gonadotropin-releasing hormone (GnRH) is the ultimate regulator of the hypothalamic-pituitary-gonadal axis, and therefore of reproductive function. Pulsatile secretion of this neuropeptide from hypothalamic GnRH neurons regulates the synthesis and secretion of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) from the pituitary gonadotrope. LH and FSH, in turn, act on the gonads and stimulate the production of gonadal steroid hormones, which feedback to regulate the hypothalamus and the pituitary. Despite the importance of the steroid hormone feedback loop in hypothalamic control of the estrus cycle, the mechanisms of estrogen and progesterone regulation of GnRH synthesis and secretion remain to be fully elucidated. The role of progesterone in the regulation of GnRH secretion from GnRH neurons will be investigated, both in a GnRH-expressing neuronal cell line and in vivo using transgenic mice as outlined in the following specific aims.
Specific Aim 1 : Determine the effect of progesterone on GnRH secretion, in the presence or absence of estrogen, in GT1-7 cells.
Specific Aim 2 : Determine the mechanism of progesterone regulation of GnRH secretion.
Specific Aim 3 : Determine whether neuronal PR is required normal fertility in vivo using a central nervous system neuron-specific PR knock-out mouse model. PUBLIC HEALTH RELVANCE: Proper regulation of GnRH expression and pulsatile secretion by neurons in the hypothalamus is important for a number of physiological processes, including puberty, the menstrual cycle, pregnancy, and menopause. Malfunction of the hypothalamic-pituitary-gonadal axis results in pathophysiological states, including infertility. Therefore, understanding the mechanisms of GnRH regulation is critical for developing our knowledge of reproduction in mammals, including humans.

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Rank: 26
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Retrieved Text: Polycystic Ovarian Syndrome (PCOS) is a female reproductive disorder. As its name implies, it is characterised by multiple cystic growths on the ovaries (hence the name polycystic ovaries).
PCOS develops when the ovaries are stimulated to produce excessive amounts of male hormones (androgens), particularly testosterone. This may happen either through the release of excessive luteinising hormone (LH) by the pituitary gland or through high levels of insulin in the blood (called hyperinsulinaemia) in women whose ovaries are sensitive to this stimulus.
PCOS comprises of a complex set of symptoms with research to date suggesting that insulin resistance is a leading cause.
A majority of patients with PCOS (some studies say all) have what is called insulin resistance. Insulin resistance is a common finding and is not related to overweight issues alone – is can exist among both normal weight and overweight women.
LH (luteinising hormone) over FSH (follicle stimulating hormone) dominance.
PCOS is the most common cause of short or absent periods It affects about 4-7% of normally menstruating women. These women may have reduced fertility and an increased risk of miscarriage.
What is the reason and risk factors?
These factors below can either be causes of PCOS or can increase your risk of getting PCOS.
Irregular menstrual cycles, short cycles, lack of menstruation.
Elevated serum androgens (male hormones), – specifically testosterone, androstenedione, and dehydroepiandrosterone sulphate (DHEAS), causing excessive hair growth as mentioned above.
It is unfortunate that many women who suffer from polycystic ovarian syndrome are not aware that there are natural ways to help. This is a condition where the ovaries produce cysts. The

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Retrieved Text: Follicle Stimulating Hormone (FSH) is a hormone that is vital for reproduction and puberty. Read more below to learn about its functions.
What is Follicle Stimulating Hormone?
Follicle Stimulating Hormone (FSH) is a gonadotropic hormone secreted by the pituitary gland. FSH is important for development during puberty as well as the function of the reproductive organs (R).
In men, FSH acts on the testes to stimulate sperm production (spermatogenesis). FSH stimulates testicular growth and aids the production of an androgen binding protein (R).
This androgen binding protein is crucial for the development of normal spermatogenesis and for maintaining maturing sperm cells (R).
The production of FSH is regulated by the circulating levels of testosterone and inhibin, both of which are produced in the testicles. If testosterone levels are high, FSH secretion decreases; if testosterone levels are low, FSH secretion increases (R).
Raised levels of FSH is a sign of malfunction in the testes. If the testes don’t produce enough testosterone, FSH production rises (R).
FSH is essential to normal sperm production. In the absence of FSH, puberty may not occur and infertility due to lack of sperm or low sperm quality may occur. Low FSH levels can cause delayed puberty and limited sperm production, but you can still be fertile (R).
In Women, FSH is essential to the pubertal development and the proper function of the ovaries. FSH regulates the secretion of estrogen (R).
When hormone levels fall towards the end of the menstrual cycle, the pituitary gland is stimulated to produce more FSH. This increase in FSH makes the ovary produce more oestradiol and

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Retrieved Text: Zoladex (goserelin; AstraZeneca/TerSera Therapeutics) is a gonadotropin-releasing hormone (GnRH) receptor agonist which acts on the pituitary gland to stimulate luteinizing hormone (LH) release, resulting in a temporary surge in serum testosterone levels known as "flare." Persistent use of GnRH agonists over time causes downregulation of GnRH receptors in the pituitary gland, generating a significant reduction in LH and follicle-stimulating hormone secretion. This has the effect of complete shutdown of testosterone production in the testes, resulting in chemical castration.

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Retrieved Text: The physicians at Texas Fertility Center want patients to know that male factor infertility is just as common as female infertility. Many factors can cause fertility issues in men, including structural problems and hormonal imbalances. As a result, there are many treatments available to address the causes of male factor infertility.
One treatment is clomiphene citrate, or Clomid, a medication that our Austin fertility specialists also use to treat female infertility. Physicians suggest Clomid for men with low sperm counts.
In some men, a low sperm count is caused by a low testosterone level. It might seem logical to give more testosterone to a man with a low testosterone level; however, doing so can actually decrease his sperm count. A similar situation exists in women, as birth control pills with estrogen prevent egg development and ovulation.
A 1999 clinical study at Texas Fertility Center found that Clomid caused a statistically significant increase in sperm concentration. In some cases, the increase was so great that couples who initially had no alternative other than IVF were able to conceive with IUI instead.
Instead of prescribing testosterone to treat male factor infertility, physicians will prescribe Clomid, the same drug that our Austin fertility specialists give to women to help them ovulate. In both men and women, Clomid binds to receptors in the brain to increase the production of follicle stimulating hormone, FSH, and luteinizing hormone, LH.
In women, FSH and LH induce egg development and ovulation.
In men, FSH leads to an increase in sperm production and LH leads to an increase in testosterone production.
While

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Input Text: Answer the following question given this paragraph: 

Figure 20.26 Arteries Supplying the Head and Neck The common carotid artery gives rise to the external and internal carotid arteries. The external carotid artery remains superficial and gives rise to many arteries of the head. The internal carotid artery first forms the carotid sinus and then reaches the brain via the carotid canal and carotid foramen, emerging into the cranium via the foramen lacerum. The vertebral artery branches from the subclavian artery and passes through the transverse foramen in the cervical vertebrae, entering the base of the skull at the vertebral foramen. The subclavian artery continues toward the arm as the axillary artery.


Q: The common carotid artery gives rise to the external and internal carotid arteries. the external carotid artery remains superficial and gives rise to many arteries of this?

 Choices:

- back

- head

- stomach

- chest

A:

Target Text: head

#### Retrieved Documents ####

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Retrieved Text: 1. Rr. caroticotympanici penetrating the tympanic cavity.
2. A. ophthalmica, the ophthalmic artery, penetrates through the canalis opticus into the cavity of the orbit along with n. opticus, where it splits into its final branches. On the way to the eye socket gives a number of branches.
8) a. dorsalis nasi descends along the edge of the back of the nose.
3. A cerebri anterior, the smaller cerebral artery, moves forward and medially to the beginning of the longitudinal groove of the brain, bends around the corpus calorus and stretches back along the inner surface of the brain hemisphere to the beginning of the occipital lobe, giving it back to the cortex. At the beginning of the longitudinal groove of the brain connects with the same side artery of the other side with the help of the transverse stem, a. communicans anterior.
A. carotis interna, the internal carotid artery, starting from the common carotid artery, rises to the base of the skull and enters the canalis caroticus of the temporal bone. In the neck it does not give branches; at the very beginning lies outwards from a. carotis externa, respectively, the development of the lateral trunk of the dorsal aorta, but soon begins to go to the medial surface of the latter. According to the curvature of canalis caroticus, the internal carotid artery, passing first vertically in it, then bends in the anteromedial direction and, at the apex of the temporal bone, enters the cranial cavity through the foramen lacerum; curving upward, it rises along the sulcus caroticus of the

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Retrieved Text: Hello, everyone. This is Joao from Kenhub and welcome to another anatomy tutorial where this time I'm going to be talking about the parapharyngeal space, specifically the different blood vessels that we find in this region.
And right now, we’re looking at an image where we see the back or the dorsal view of the neck specifically, the pharynx where we see the different pharyngeal blood vessels, arteries, and veins. And we’re going to be describing all these structures that you see here.
Now the first thing we’re going to be doing here on this tutorial is describing the different arteries that you find here on this image.
And that includes the brachiocephalic trunk, the common carotid, the external carotid, the superior thyroid, superior laryngeal, the occipital artery, ascending pharyngeal artery, and also we’re going to be seeing the internal carotid, the thyrocervical trunk, and finally the inferior thyroid.
Let’s start off with the very first one on the list that you see now highlighted in green on this image. This is known as the brachiocephalic trunk. You can also call it the brachiocephalic artery. And this is an artery of the mediastinum.
The brachiocephalic trunk is the first branch of this structure here which is known as the aortic arch. As you can also see how it branches out of this aortic arch. And soon after it emerges, the brachiocephalic artery will be dividing into two other arteries including the common carotid artery which you see here.
So the right common carotid artery because we are looking at the dorsal view

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Rank: 2
Score: 118.272484
Retrieved Text: The external carotid artery flows upward on the side of the head to branch into various structures in the neck, face, jaw, scalp, and base of the skull. The main vessels that originate from this artery are: (1) the superior thyroid artery, to the hyoid bone, larynx, and thyroid gland; (2) the lingual artery, to the tongue, muscles of the tongue, and salivary glands below the tongue; (3) the facial artery, to the pharynx (throat), palate, chin, lips, and nose; (4) the occipital artery, to the scalp on the back of the skull and various muscles in the neck; and (5) the posterior auricular artery, to the ear and scalp over the ear. The external carotid artery terminates by division into the maxillary and superficial temporal arteries.
The facial vein is a branch of the external carotid vein. It returns deoxygenated blood from the pharynx (throat), palate, chin, lips, and nose back to the heart.
The internal carotid artery enters the skull and supplies the anterior part of the brain (via cerebral branches), the eye and its appendages, and sends branches to the forehead and nose. It has many curvatures in different parts of its path. When it passes through the carotid canal and the side of the body of the sphenoid bone, it has double curvature and looks like the italic letter S.
It moves up at a right angle to the pharynx and then towards the skull's base. At this point it will goes into the carotid canal, which is located in the temporal bone's petrous portion.

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Rank: 3
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Retrieved Text: Can the External Carotid Artery Be Securely Ligated using the BRIG Technique in the Treatment of Carotid Disease?
Cite this article as: De Vleeschauwer P, Van den Broeck T, Vissers S, Debeuf J, De Feyter K, Waets P. Can the External Carotid Artery Be Securely Ligated using the BRIG Technique in the Treatment of Carotid Disease?. Clin Surg. 2018; 3: 2073.
Introduction: Ligating the external carotid artery during carotid artery surgery remains a debatable act for many surgeons due to the potential impact of facial arterial blood supply. However, in our previous report on the BRIG technique to treat carotid disease, only one patient developed jaw claudicating and no other symptoms of facial hypo-perfusion. The goal of this study is to scientifically substantiate these clinical findings by determining the impact of interruption and restoration of the carotid blood flow on the External Carotid Artery Stump Pressure (ECASP).
Methods: A prospective proof-of-concept study was performed, including nine consecutive patients who underwent BRIG surgery for symptomatic ICA stenosis or asymptomatic high grade ICA stenosis. A Javid shunt was used to measure the ECASP and the CASP during the procedure. An arterial line was used to measure systemic blood pressure. To compare the ECASP during clamping and after the restoration of ICA blood flow, multiple Students’ T-testing was performed, correcting for multiple testing using the Holm-Sidak method.
Results: ECASP and ECASP /BP index did not significantly change during clamping of the carotid bifurcation and after restoration of cerebral blood. Both CASP and ECASP did not change significantly during clamping of the common carotid

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Rank: 4
Score: 115.32471
Retrieved Text: What Does a Swishing Sound Suggest When Auscultating a Left Carotid Artery?
The detection of a bruit, or swishing sound, when auscultating the left carotid artery suggests turbulence in blood flow through the vessel, which indicates stenosis or atherosclerosis, reports MedicineNet. The accumulation of plaque in the carotid arteries is a cyclic process, which causes increased pressure that causes further plaque buildup.
The common carotid artery divides into internal and external branches near the larynx, explains Mayfield Clinic. The most common location for the development of carotid stenosis is at this division point. Because the internal carotid arteries supply blood to the brain, the presence of carotid artery disease significantly increases the risk of stroke and subsequent brain damage. Doctors use ultrasound, computed tomography imaging and magnetic resonance angiography to confirm the diagnosis of carotid stenosis. Treatment focuses on reducing the risk of stroke through the prevention of blood clot formation and further plaque development and the removal of existing plaque deposits.
Research links the development of carotid artery disease to smoking, poorly controlled diabetes, high blood pressure and high cholesterol, according to MedicineNet. Carotid atherosclerosis usually develops over a period of time as inflammation causes the development of plaque, which hardens and causes further inflammation. The narrowing of the vessel causes increased pressure, which can cause a piece of plaque to break free and reduce or block blood flow in the carotid artery or in subsequent smaller vessels.
Find Carotid Artery Sounds. Learn More!
What Are the Symptoms of a Carotid Artery Blockage?
What Are the Signs and Symptoms of a

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Rank: 5
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Retrieved Text: ✓ Carotid body tumors are a rare but potentially difficult surgical entity. Their pathology, physiology, and natural history are reviewed along with surgical results reported in the literature. A surgical approach for removal of these tumors is presented which differs significantly from the recommended techniques in that emphasis is placed on intraoperative monitoring of cerebral blood flow, the selective use of shunts, a tumor-adventitial plane of dissection, preservation of the carotid artery complex, and mobilization of the parotid gland. Thirteen cases using these techniques are reviewed. The mortality rate and the incidence of cerebrovascular sequelae were both 0%. The major morbidity consisted of injury to the lower cranial nerves in five patients (39%) with tumors larger than 5 cm in length.
Address reprint requests to: Thoralf M. Sundt, Jr., M.D., Department of Neurologic Surgery, Mayo Clinic, Rochester, Minnesota 55905.
Left: Classic angiographic pattern with widening of the bifurcation and stretching of the external and internal carotid arteries by a highly vascular carotid body tumor. Right: Postoperative angiogram demonstrates good flow through both the external and internal carotid arteries after tumor removal.
Angiograms showing a large carotid body tumor extending to the base of the skull (left), and receiving a significant blood supply from muscular branches of the vertebral artery (right).
Contrast-enhanced computerized tomography scan demonstrating erosion of the petrous bone and extension of a carotid body tumor into the cerebellopontine angle (arrow).
Operative sequence. Upper Left: The parotid gland has already been mobilized and the rostral extent of the tumor delineated. The common facial vein is often incorporated into the tumor

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Rank: 6
Score: 109.96833
Retrieved Text: Question: I lost the vision in my right eye for five minutes. I could not see anything with my right eye. It was a very terrifying experience. I saw my doctor the next day and he sent me to a vascular specialist. The vascular specialist did a carotid sonogram, which showed that my right carotid artery was completely closed. The doctor told me that I should not worry because my left carotid artery is “wide open”. In any case, he said there is nothing that can be done about the blocked carotid artery on the right side. I am very nervous about this. I fear that I will have a stroke due to the blocked artery. Should I have an operation? What do you advise?
Answer: If the internal carotid artery is completely blocked, and the person has not had a stroke, we usually consider that to be a better situation than if the internal carotid artery is a very narrowed but still open artery. The reason is that an internal carotid artery narrowing due to a buildup of cholesterol plaque can lead to a situation where some of that plaque can break loose, travel to the brain, and cause a stroke. When the internal carotid artery is completely closed, plaque can no longer travel from the artery into the brain since there is no longer any blood flow through the artery. It is not usually the lack of circulation through an artery that causes a stroke but rather “embolization” of clot or cholesterol plaque into the

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Rank: 7
Score: 109.853134
Retrieved Text: Coding for most vascular interventional radiology (VIR) procedures starts with the catheterization code (or codes), but choosing those codes can be extremely confusing for a novice coder. The interventionalist must document both where he or she started the procedure and where he or she stopped along the way. The coder is left to interpret the documentation and choose the correct code. The first step is to decide whether the catheterization is nonselective or selective.
A common example of nonselective arterial catheterization is an aortogram. From any access point, the catheter is moved into the aorta and then removed the same way, without entering into any other arteries. The catheter can be moved up and down within the aorta, stopping one or more times to take images. It can be moved to the ostium (opening) of one of the visceral arteries. As long as it does not go into the artery, it is considered nonselective.
The most common code for this is 36200, Introduction of catheter, aorta. This code is used if the catheter started in one of the extremity arteries before being moved to the aorta. A less commonly used code is 36160, Introduction of needle or intracatheter, aortic, translumbar. This access was almost extinct but is coming back due to the increasing number of aortic stent grafts being performed. It is used to view the aneurysm sac outside a stent graft.
• 36100, Introduction of needle or intracatheter, carotid or vertebral artery, is access by a direct stick into a carotid or vertebral artery.
• 36120, Introduction of needle

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Rank: 8
Score: 107.4346
Retrieved Text: The Institute for Advanced Medical Education is accredited by the Accreditation Council for Continuing Medical Education (ACCME) to provide continuing medical education for physicians and technologists.
This course qualifies for Category A credits, and is accepted by the ARRT.
Carotid duplex examination is a well established diagnostic imaging tool to assess the status of a patient’s cerebrovascular circulation. It has been utilized since the late 1970s where its clinical application was first developed at the University of Washington. Duplex can categorize disease based on various ranges of the severity of stenosis as opposed to contrast angiography that defines stenosis based on diameter reduction. The results of carotid duplex examination can assist the clinician in determining a patient’s relative risk of stroke and also assist in determining treatment using stenting or surgical techniques. This examination relies on strong knowledge of cerebrovascular anatomy and pathophysiology, proper examination technique and quality instrumentation which will be presented in this online review course.
acoustic shadows from the progressive fibrotic plaque. The deposits that cause this include additional collagen, calcium and cellular debris. An ulcerative lesion can occur from the deterioration of smooth fibrous plaque and may result in distal embolization. Ulceration is associated with intraplaque hemorrhage and can be seen sometimes as swirls of color Doppler within the plaque. As the plaque protrudes into the arterial lumen and becomes altered, it is at a higher risk of embolization. The most common sites for atherosclerosis include branches, bifurcations and origins of vessels. The vast majority of carotid duplex examinations will be to assess the presence

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Score: 107.12224
Retrieved Text: Carotid arteries take blood up to the front of each side of the brain. At the base of the brain they join in a network called the “Circle of Willis. They combine with the two vertebral arteries which supply the back of the brain. In many patients blockage of one artery can be taken over by another. At least a quarter of patients have an incomplete or fully developed Circle of Willis and this doesn’t occur.
Narrowing of the Carotid Arteries typically occurs in the middle of the neck where the arteries divide from the common Carotid Artery coming up from the chest into the Internal Carotid Artery which supplies the brain and the External Carotid Artery which supplies the face. Flow abnormalities at this point seem to cause sheer stresses which cause internal intimal injuries. This is then progressive and causes build up of atheroma, fibrosis, cholesterol and even calcium. The intima can be disrupted leading to an ulcer inside the walls. In this ulcer platelets can develop.
Platelets or debris from the ulcer will be carried by the blood supply upwards and this may cause blindness in the eye on that side (amaurosis fugax)) or a stroke affecting that hemisphere which will then affect the arm or leg on the other side. Speech and comprehension can also be affected. Carotid Artery Disease is strongly associated with diabetes, smoking and coronary artery disease. Carotid Artery Disease is a common cause of stroke. Because there are no symptoms of claudication as there are in the legs, the Carotid

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Rank: 10
Score: 105.15895
Retrieved Text: The objective of carotid endarterectomy (CEA) is to prevent strokes. In the United States, stroke is the fifth leading cause of death overall, and women have a higher lifetime risk of stroke than men do. [1, 2] Among patients suffering a stroke, 50-75% had carotid artery disease that would have been amenable to surgical treatment.
Several prospective randomized trials have compared the safety and efficacy of CEA with those of medical therapy in symptomatic and asymptomatic patients. Data from these prospective trials have confirmed that CEA offers better protection from ipsilateral strokes than medical therapy alone in patients presenting with either symptomatic or asymptomatic carotid artery disease.
CEA is contraindicated if the patient’s general condition includes a serious illness that will substantially increase perioperative risk or shorten life expectancy. It is also contraindicated in patients who present acutely with a major stroke or in patients who experienced a major devastating stroke with minimal recovery or a significantly altered level of consciousness.
The traditional teaching was that emergency CEA in an acutely occluded carotid artery might convert an ischemic cerebral infarct to a hemorrhagic infarct, possibly resulting in death. The timing of the operation was considered optimal when the patient reached optimal recovery before elective CEA was performed. However, a few reports of improved neurologic outcomes with early intervention in patients with acute nonhemorrhagic strokes have emerged.  Careful patient selection is essential.
In a study of perioperative and long-term outcomes after CEA in hemodialysis patients, Cooper et al found that the risks of CEA in asymptomatic dialysis-dependent patients were high,

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Score: 104.08037
Retrieved Text: Carotid artery disease, also called carotid artery stenosis, occurs when the carotid arteries, the main blood vessels that carry oxygenated blood to the brain, become narrowed. The narrowing of the carotid arteries is most commonly related to atherosclerosis (a buildup of plaque, which is a deposit of fatty substances, cholesterol, cellular waste products, calcium, and fibrin in the inner lining of an artery). Atherosclerosis, or "hardening of the arteries," is a vascular disease (disease of the arteries and veins). Carotid artery disease is similar to coronary artery disease, in which blockages occur in the arteries of the heart, and may cause a heart attack.
To better understand how carotid artery disease affects the brain, a basic review of the anatomy of the circulation system of the brain follows.
The main supply of blood to the brain is carried by the carotid arteries. The carotid arteries branch off from the aorta (the largest artery in the body) a short distance from the heart, and extend upward through the neck carrying oxygen-rich blood to the brain.
There are 2 carotid arteries: the right and left. Each carotid artery then branches into an internal carotid artery and an external carotid artery. One pair (external and internal) is located on each side of the neck. Just as a pulse can be felt in the wrists, a pulse can also be felt or heard on either side of the neck over the carotid arteries.
Why are the carotid arteries important?
Because the carotid arteries deliver blood to the brain, carotid artery disease can have serious implications

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Score: 103.68079
Retrieved Text: Glagov S, Weisenberg E, Zarins CK, Stankunavicius R, Kolettis GJ. Compensatory enlargement of human atherosclerotic coronary arteries. The New England Journal of Medicine 1987;316:1371e5.
 Pasterkamp G, Fitzgerald PF, de Kleijn DP. Atherosclerotic expansive remodeled plaques: a wolf in sheep's clothing. Journal of Vascular Research 2002;39: 514e23.
 Gyongyosi M, Yang P, Hassan A, et al. Intravascular ultrasound predictors of major adverse cardiac events in patients with unstable angina. Clinical Cardiology 2000;23:507e15.
 Pasterkamp G, Galis ZS, de Kleijn DP. Expansive arterial remodeling: location, location, location. Arteriosclerosis, Thrombosis, and Vascular Biology 2004;24: 650e7.
 Eigenbrodt ML, Bursac Z, Tracy RE, Mehta JL, Rose KM, Couper DJ. B-mode ultrasound common carotid artery intima-media thickness and external diameter: cross-sectional and longitudinal associations with carotid atherosclerosis in a large population sample. Cardiovascular Ultrasound 2008;6:10.
 Polak JF, Kronmal RA, Tell GS, et al. Compensatory increase in common carotid artery diameter. Relation to blood pressure and artery intima-media thickness in older adults. Cardiovascular health study. Stroke; a Journal of Cerebral Circulation 1996;27:2012e5.
 Johnsen SH, Joakimsen O, Singh K, Stensland E, Forsdahl SH, Jacobsen BK. Relation of common carotid artery lumen diameter to general arterial dilating diathesis and abdominal aortic aneurysms: the tromso study. American Journal of Epidemiology 2009;169:330e8.
 Eigenbrodt ML, Sukhija R, Rose KM, et al. Common carotid artery wall thickness and external diameter as predictors of prevalent and incident cardiac events in a large population study. Cardiovascular Ultrasound 2007; 5:11.
 Berk BC, Korshunov VA. Genetic determinants of vascular remodelling. The Canadian Journal of Cardiology 2006;22(Suppl. B):6Be11B.
 Bis JC, Kavousi M, Franceschini N, et al.

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Score: 103.52115
Retrieved Text: Copyright: © 2017 Shibata Y. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Agenesis of the bilateral internal carotid arteries is a rare disease. There have been few case reports of subjects who developed cerebral infarction, intracranial hemorrhage or subarachnoid hemorrhage. We experienced a rare case of agenesis of the bilateral internal carotid arteries in which the patient developed vertigo. A 63-year-old woman suddenly became dizzy one morning after waking up and was admitted to our hospital. Brain Computed Tomography (CT) and Magnetic Resonance (MR) imaging demonstrated no intracranial hemorrhage or cerebral infarction. CT angiography and MR angiography showed the enlargement and invagination of the basilar artery into the pons. Her dizziness disappeared with conservative therapy. Our case was very rare because the patient was diagnosed with agenesis of the bilateral internal carotid arteries before the development of major cerebrovascular disease. There are some possible mechanisms of vertigo in our case: One is direct pulsatile pontine compression by the elongated basilar artery; another is transient or chronic cerebral ischemia caused by abnormal circulation.
Agenesis of the bilateral internal carotid arteries is a rare disease. There have been few case reports of subjects who developed cerebral infarction, intracranial hemorrhage or subarachnoid hemorrhage [1-4]. We experienced a rare case of agenesis of the bilateral internal carotid arteries in which the patient developed vertigo.
The patient, a 63-year-old woman, had been treated for hypertension and hyperlipidemia for

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Rank: 14
Score: 102.502846
Retrieved Text: Background: The neurovasculature dynamically responds to changes in cerebral blood flow by vascular remodeling processes. Serial imaging studies in mouse models could help characterize pathologic and physiologic flow-induced remodeling of the Circle of Willis (CoW).
Method: We induced flow-driven pathologic cerebral vascular remodeling in the CoW of mice (n=3) by ligation of the left Common Carotid Artery (CCA), and the right external carotid and pterygopalatine arteries, increasing blood flow through the basilar and the right internal carotid arteries. One additional mouse was used as a wild-type control. Magnetic Resonance Imaging (MRI) at 9.4 Tesla (T) was used to serially image the mouse CoW over three months, and to obtain threedimensional images for use in Computational Fluid Dynamic (CFD) simulations. Terminal vascular corrosion casting and scanning electron microscope imaging were used to identify regions of macroscopic and microscopic arterial damage.
Results: We demonstrated the feasibility of detecting and serially measuring pathologic cerebral vascular changes in the mouse CoW, specifically in the anterior vasculature. These changes were characterized by bulging and increased vessel tortuosity on the anterior cerebral artery and aneurysm- like remodeling at the right olfactory artery origin. The resolution of the 9.4T system further allowed us to perform CFD simulations in the anterior CoW, which showed a correlation between elevated wall shear stress and pathological vascular changes.
Conclusion: In the future, serial high-resolution MRI could be useful for characterizing the flow environments corresponding to other pathologic remodeling processes in the mouse CoW, such as aneurysm formation, subarachnoid hemorrhage, and ischemia.
Animal model, carotid artery ligation, hemodynamics, computational fluid dynamics, magnetic

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Rank: 15
Score: 101.83683
Retrieved Text: Background: Hypoplasia of the internal carotid artery is a rare congenital malformation. It has been mainly associated with aneurysms and other pathologies but not in association with paraganglioma. The incidence is ‹ 0.01% of all the anomalies of carotid vessels. Although the exact cause is unknown, it is thought to represent a sequel to an insult due to mechanical causes or hemodynamic stress but perhaps also involves aspects of molecular biology of embryonic development.
Clinical case: We describe the case of a 37 year-old female patient with paraganglioma associated with hypoplasia of the internal carotid artery, which was found incidentally during surgery. Previous angiographic studies as well as other analyses were carried out, but we failed to detect hypoplasia of the internal carotid artery. Tumor was removed along with ligation of the external carotid artery due to injury. The hypoplastic internal carotid artery was left intact.
Conclusion: Angiographic studies of the base of the skull are important as well as hemodynamic analysis in order to not overlook these anomalies. The patient had a satisfactory evolution without sequelae.
Key words: Hypoplasia internal carotid artery, paraganglioma.
Ibarra de-Grassa B, Roulero-Vidal FJ, Alarcón-Alcaraz MM, Arenillas-Lara JF, et al. Estudio de la arteria carótida interna hipoplásica mediante tomografía computarizada helicoidal multicorte. A propósito de dos casos. Rev Neurol 2002;35:832-837.
López-Álvarez F, Bernardo-Corte MJ, Gómez-Martínez JR, Suárez-Nieto C. Agenesia unilateral de arteria carótida interna. Acta Otorrinolaringol Esp 2012;63:72-74.
Piazza P, Di Lella F, Menozzi R, Bacciu A, Sanna M. Absence of the contralateral internal carotid artery: A challenge for management of ipsilateral glomus jugula glomus vagale tumors.

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Rank: 16
Score: 101.11817
Retrieved Text: Findings: Isointense mass (a) involving the deep lobe of the left parotid which is well circumscribed and pushes the superficial lobe of the parotid (slp) laterally and the parapharyngeal space medially (pps). Note the normal locations of the contralateral superficial lobe of the parotid and parapharyngeal space. The internal carotid artery (ica) is pushed slightly posteromedially and the retromandibular vein and external carotid artery are elevated when compared to the right side. Expected course of the right facial nerve (double headed black arrow). Right deep lobe of the parotid (dlp). Right medial pterygoid muscle (mp). Right masseter muscle (mas). Lateral pterygoid muscle (lp). Right mastoid tip (mast).

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Retrieved Text: Clinical Significance of Tortuosity of The Carotid Artery and Higher Bifurcation: Report of A Case and Review of Literature .
An aberrant carotid artery is at risk of injury during routine procedures if the vessel is placed into altered relationship with structures. The incidence of these variations is reported to be between 6-40% in various series.
We present a case of 46 year old male presented with cancer of the buccal mucosa wherein a high bifurcation of carotid artery along with tortuosity of the common carotid and internal carotid artery was found.
the anatomical variations of the carotid vessels can place these vessels at risk of injury at the time of surgery and hence knowledge of these variations is essential.
carotid artery; external carotid; internal carotid; internal jugular vein; spinal accessory artery; neck dissection.
Aberrant course of Internal carotid artery in the temporal bone is often discussed, however, its variations in the neck though not rare are less frequently described . Dr. John Carney of Department of Anatomy, University of Otago, New Zealand in 1924, highlighting this variation and its importance noted that “internal carotid artery may in some cases be tortuous is mentioned in the recent editions of most of our standard textbooks, usually in small type under the heading of peculiarities or of variations” . Quoting Gray (Gray's Anatomy, 22nd edition, p. 625, 1923) he mentioned that, "The course of the artery, instead of being straight, may be very tortuous" and quoting Pierson (Pierson’s Human Anatomy, 7th edition, p. 747, 1919), "In its cervical portion the internal carotid occasionally

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Retrieved Text: What Is The ICD-10 Code For Moyamoya?
Moyamoya is a neurological disorder that occurs because of blocked arteries present at the base of brain. The name moyamoya has been derived from a Japanese word because this condition was first identified by Japanese. In this health condition, the blood vessels present in the brain starts to become narrow, which in turn creates blockage leading to stroke. Till date there is no medication available that can either stop or reverse the effect of moyamoya disease. Treatment for this problem is focused on maintaining normal blood flow in the brain for eliminating the risk of stroke.
For reimbursement purpose, the disease is diagnosed with ICD-10 I67.5. This is the latest code which came into existence from October 2018.
After the problem is identified immediate treatment is initiated. If the problem is at an early stage then it can treated with effective medication but if the problem is become severe or complicated then surgery is prescribed. Doctors recommend that one should not leave the condition untreated for a prolonged period of time else it can have fatal effect.
For understanding moyamoya, it is very important to understand the circulatory system present in neck and head of an individual. The flow starts from the aorta, which is a carotid artery and then divides near the larynx into two parts i.e. internal and external carotid arteries. Internal arteries are responsible for maintaining required blood flow in the front and sides of the brain, whereas; eternal arteries are responsible for maintaining required blood flow in the face

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Score: 98.237434
Retrieved Text: YUHSpace: Coexistence of a carotid body tumor and thyroglossal duct carcinoma with cervical lymph node metastasis.
Coexistence of a carotid body tumor and thyroglossal duct carcinoma with cervical lymph node metastasis.
Thyroglossal duct carcinoma is uncommon, occurring in approximately 1% of all thyroglossal duct remnants. This rare neoplasm is characterized by relatively nonaggressive behavior with infrequent lymph nodal spread. Another rare neoplasm of the head and neck region is a carotid body tumor. A 78-year-old woman with a 3-year history of midline and bilateral neck masses was referred to us. Fine needle aspiration biopsies and a computed tomography scan suggested the diagnosis of thyroglossal duct carcinoma with cervical lymph node metastasis. Interestingly, the left-side neck mass was found to be splaying the carotid bifurcation, on computed tomography imaging. Carotid arteriography demonstrated a highly vascular mass in the bifurcation of the carotid artery that was compressing the internal and external carotid arteries. To our knowledge, this is the first reported instance of a thyroglossal duct carcinoma with neck metastasis accompanied by a carotid body tumor. In addition, the carotid body tumor in this case mimicked neck metastasis from the thyroglossal duct carcinoma.

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Retrieved Text: The carotid arteries in the neck are the lifeline to your brain and as with any artery, plaque buildup can be life threatening. As a skilled vascular surgeon, Dr. Youssef Rizk of the Vascular and Endovascular Institute of Michigan in Clinton Township, Michigan, can help with the diagnosis, control and treatment of carotid artery disease.
A carotid artery is one of the major blood vessels in the neck. It supplies blood to the brain, neck, and face. There are 2 of these arteries on each side of the neck.
Carotid artery disease occurs when the carotid arteries narrow, often due to atherosclerosis, or the buildup of plaque in the artery. This can stop blood from flowing to the brain. If a blood clot gets stuck because of this plaque, a patient will have a stroke. This narrowing of the carotid arteries is called carotid artery stenosis.
What puts a patient at risk of carotid artery diseases?
Lifestyle changes can reduce some of these risks, but genetics, age, and preexisting conditions may not have prevention measures that are possible.
Most of the time, carotid artery disease doesn't cause any symptoms. If Dr. Rizk suspects carotid artery disease based on other factors, he can perform a test to determine if there's plaque buildup in the carotid artery.
What can be done to protect a patient from stroke when plaque is present in the carotid artery?
Dr. Rizk can perform an operation to remove plaque from the carotid artery if the narrowing is severe. If the narrowing is less severe, he can prescribe medication to prevent

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Rank: 21
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Retrieved Text: My husband has a 5 centimeter AAA. What would be the preferred optimal procedure to repair.
Can my 88 yo father-in-law undergo an endograft procedure?
Can a blockage of my iliac artery cause abdominal pain?
How is abdominal pain due to "Celiac Compression Syndrome" treated?
Why do I have a lot of abdominal pain after eating?
Can antibiotics cause rupture of blood vessels?
Can I wait more than a week to have my aortic aneurysm repaired?
My doctor told me not to worry about my 3.1 cm aortic aneurysm-should I be?
What is the optimal blood pressure to keep an aneurysm from expanding?
Why have my toes turned blue after aortic aneurysm repair?
My husband's aneurysm repair needs to be re-done. Why is that?
Will femoral aneurysm repair make an aortic aneurysm stent repair more difficult?
Is my mother too old to have her aneurysm repaired?
Should I have a stent or a bypass?
Why is my arm so swollen after pacemaker?
Why is my arm swollen?
Should I switch from Coumadin to Pradaxa?
Is my Baker's cyst an indication of a vascular problem?
Can a stroke be caused by hyperextending the neck?
The skin of my lower legs is turning brown. What can be done about it?
Should I worry about a lump on my wrist at the site of a cardiac cath I had done last week?
Is ankle swelling a normal finding after a cardiac cath and stent placement through the femoral artery in the groin?
I have pain in the leg where my heart cath was done. Is this normal?
Is it normal for my leg to still hurt three weeks after a cardiac cath?
Why

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Score: 97.3671
Retrieved Text: The disease typically affects the renal and extracranial carotid arteries, but it has also been noted in most medium-sized arteries throughout the body, most commonly the mesenteric, external iliac, and brachial arteries.  Disease manifestations depend on the arterial bed involved: most often, the extracranial carotid or vertebral arteries are associated with headache (generally migraine-type), pulsatile tinnitus, neck pain, or dizziness, whereas the renal arteries are often associated with hypertension. More severe symptoms such as transient ischemic attack (TIA), stroke, ruptured aneurysm, or a carotid or vertebral artery dissection can develop in patients with cerebrovascular FMD. [1, 3] The diagnosis of FMD is made by imaging studies; there is no blood test for FMD. and biopsies are not performed.
Angiogram of type 1 fibromuscular dysplasia in a 43-year-old female patient with multiple transient ischemic attacks. Note the multiple saccular dilatations of the internal carotid artery between the first and second cervical vertebrae.
Although conventional computed tomography (CT) scanning has no role in the diagnosis of fibromuscular dysplasia, it is essential for assessing the intracranial consequences of the disease. CT angiography (CTA) may be used as a noninvasive means of diagnosing the vascular changes of FMD. CTA may display the pathognomonic string of beads appearance of the internal carotid artery. It is recommended that CTA findings be confirmed with carotid angiography.
Current resolution (voxel sizes) of CT may limit the usefulness of this modality in the diagnosis of subtle cases. As this technique improves, its negative predictive value may increase, so as to make it useful in excluding FMD from

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Score: 96.972626
Retrieved Text: The diameter of peripheral arteries increases during the atherosclerotic process. This relationship, between carotid and brachial enlargement and the increasing severity burden of the atherosclerotic process, implies that the diameter of arteries is an indicator of risk for cardiovascular events.
by preserving the lumen diameter and blood flow and may influence the clinical presentation of atherosclerotic vascular disease. However, the data have also shown that remodelling of the arterial wall and enlargement of the arterial diameter also affect undiseased vascular segments. Thus the process of remodelling of the arterial wall is not completely understood (2-4).
The biological and physiological significance of enlargement of the arterial diameter during the atherosclerotic process and the mechanisms that are involved in this process are not fully comprehended. Labropoulos et al have found that all arteries dilate in the stage of early atherosclerotic plaque formation and they concluded that dilation of the artery occurs to preserve luminal area (5). Therefore the increase in arterial diameter in subjects with atherosclerosis is usually discussed in terms of compensatory enlargement to preserve luminal area.
However the results of the investigations of Jensen - Urstadt et al have suggested that the mechanisms behind the increase in artery diameter may be related to regulatory mechanisms present before compensatory enlargement of the lumen (6). It is possible that the vessel diameter in itself is a measure of vascular regulatory function. In advanced stages of atherosclerosis the increased diameter is probably a consequence of the long term harmful effects of risk factors that initiate the inflammatory process, with the accumulation of

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Rank: 24
Score: 96.712776
Retrieved Text: As novel endovascular strategies are developed for treating neurological disease, there is an increasing need to evaluate these techniques in relevant preclinical models. The use of non-human primates is especially critical given their structural and physiological homology with humans. In order to conduct primate endovascular studies, a comprehensive understanding of the carotid anatomy is necessary. We therefore performed a detailed examination of the vessel lengths, lumen diameters and angles of origin of the baboon extracranial carotid system.
We characterized the extracranial carotid system often male baboons (Papio anubis, range 15.1–28.4 kg) by early post-mortem dissection. Photographic documentation of vessel lengths, lumen diameters, and angles of origin were measured for each segment of the carotid bilaterally.
The common carotid arteries averaged 94.7 ± 1.7 mm (left) and 87.1 ± 1.6 mm (right) in length. The average minimal common carotid lumen diameters were 3.0 ± 0.3 mm (left) and 2.9 ± 0.2 mm (right). Each animal had a common brachiocephalic artery arising from the aorta which bifurcated into the left common carotid artery and right braciocephalic artery after 21.5 ± 1.6 mm. The vascular anatomy was found to be consistent among animals despite a wide range of animal weights.
The consistency in the Papio anubis extracranial carotid system may promote the use of this species in the preclinical investigation of neuro-interventional therapies.
There has been a recent interest in developing aggressive interventional strategies for the treatment of a variety of neurological diseases including stroke, subarachnoid hemorrhage, and head trauma [1–4]. Successful translation of these therapies to the clinical arena, however, is critically

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Rank: 25
Score: 96.594795
Retrieved Text: Our NorthShore Neurological Institute experts use a collaborative approach to ensure patients receive the best full-service care for stroke, carotid artery blockage and other serious medical conditions as a result of carotid artery disease. Our uniquely qualified multidisciplinary specialists are recognized in providing high-quality diagnostic and carotid artery blockage treatment. All four of our NorthShore hospitals are Certified Primary Stroke Centers, a stringent designation given by the Joint Commission.
Carotid arteries located in the neck have a very important job: through them flows the blood that carries the oxygen and nutrients the brain needs to work properly. Carotid artery disease develops when the arteries narrow or become blocked due to fatty plaque buildup (also known as atherosclerosis). A somewhat silent disease—that may not produce obvious signs or symptoms—carotid artery blockage is a major cause of stroke.
Since carotid artery blockage accounts for a significant proportion of strokes that occur in the United States, patients who come to our hospitals with transient stroke-like symptoms—often associated with narrowing of the arteries—benefit from the combined knowledge and experience of our 24/7 Acute Stroke Team.
At the NorthShore Neurological Institute, our highly skilled vascular and endovascular specialists conduct thorough evaluations of patients to determine the best course of carotid artery blockage treatment. Our team uses a number of sophisticated imaging technologies, including carotid ultrasound, CT angiography of the neck, magnetic resonance angiography and catheter cerebral angiography, to look deep within the arteries and assess the extent of carotid artery blockage or damage.
Some patients may benefit from medications and lifestyle changes including diet; while

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Rank: 26
Score: 96.56368
Retrieved Text: What is a carotid artery aneurysm?
A carotid artery aneurysm is an abnormal swelling in the wall of the carotid artery. The carotid artery is the large artery which takes blood from the heart to the head.
What are the symptoms of carotid artery aneurysms?
Symptoms of a carotid artery aneurysm include transient ischemic attacks (TIAs). These TIAs are mini-strokes or episodes in which a person develops symptoms of strokes that resolve completely after a short duration. These symptoms of TIAs include blurred vision and numbness of the face, arms or legs.
Persons with carotid artery aneurysms can also develop strokes and present with symptoms like drooping of the face, difficulty talking and weakness of the arm or leg.
As the aneurysm grows and becomes larger, it can press on other structures in the neck and cause symptoms like hoarseness of the voice, difficulty swallowing and swelling of the face.
What are the causes of carotid artery aneurysms?
Atherosclerosis is the most common cause of carotid artery aneurysms. This condition is caused by the deposition of fatty material in the walls of blood vessels.
Other causes of these aneurysms include penetrating and blunt trauma to the neck which can occur after motor vehicle accidents. Birth defects can lead to the development of weakened arteries which are prone to ballooning.
How does carotid artery aneurysm surgery work?
Carotid artery aneurysms are usually treated surgically by removing the abnormal section of the wall and placing a conduit to bypass that section. This conduit if often created from veins removed from the patient’s legs or arteries taken from other

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Rank: 27
Score: 95.70961
Retrieved Text: Your carotid arteries are the main pipelines for carrying blood to your brain. You have one on each side of your neck. You can feel your pulse by pressing on your carotid artery just under your jawline.
Carotid stenosis — also called carotid artery disease — occurs when a fatty substance called plaque or atherosclerosis builds up inside an artery. The plaque buildup can narrow an artery, or block it completely. It can also cause a blood clot to form, which can lead to a stroke.
In the U.S., stroke is one of the leading causes of death. About 20 percent of all strokes result from carotid stenosis.
People who have a family history of stroke are at higher risk for carotid stenosis.
The incidence of narrowed or blocked arteries also increases with age. Patients younger than 60 years old have less than 1 percent incidence of carotid stenosis whereas patients older than 80 have a 5 percent to 7.5 percent incidence of carotid stenosis.
In its early stages, carotid stenosis typically causes no symptoms. The first symptom is usually a stroke or transient ischemic attack (TIA). TIAs typically do not cause lasting damage, but someone who has had a TIA is at risk for a major stroke.
Patients with symptoms for TIA or stroke should have their carotid arteries evaluated to determine if there is narrowing in these vessels.
Carotid Ultrasounds — A non-invasive test that determines the speed that blood passes through the carotid arteries.
Magnetic Resonance Angiography or Computed Tomography Angiography — Non-invasive tests that create 2-D and 3-D images of

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Retrieved Text: 12Hospital de Base de Brasília, Brasilia DF, Brazil.
Dissection of cervical arteries constitutes a medical emergency. Although relatively rarely, activities classified as sports and recreation may be a cause of arterial dissection independently of neck or head trauma. The purpose of the present paper was to present a series of cases of cerebrum-cervical arterial dissection in individuals during or soon after the practice of these sports activities.
Retrospective data on patients with arterial dissection related to sports and recreation.
Forty-one cases were identified. The most frequently affected vessel was the vertebral artery. A large variety of activities had a temporal relationship to arterial dissection, and jogging was the most frequent of these. This is the largest case series in the literature.
Arterial dissection may be a complication from practicing sports.
A dissecção das artérias cervicais é uma emergência médica. Embora de forma relativamente rara, certas atividades descritas como esportes e recreação podem ser a causa de dissecção arterial independentemente de trauma de crânio ou cervical. O propósito do presente estudo é apresentar uma série de casos de dissecção de artérias cérebro-cervicais em indivíduos durante ou logo após a prática destas atividades desportivas.
Dados retrospectivos de pacientes com dissecção arterial relacionada à prática de esportes e recreação.
Quarenta e um casos foram identificados. A artéria mais frequentemente afetada foi a vertebral. Uma grande variedade de atividades teve relação temporal com a dissecção arterial, sendo a corrida a mais frequente delas. Esta é a maior série de casos da literatura.
Dissecção arterial pode ser uma complicação da prática de esportes.
Dissection of cervical arteries can lead to

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Rank: 29
Score: 95.47947
Retrieved Text: Address reprint requests to: Fredric B. Meyer, M.D., Department of Neurosurgery, Mayo Clinic, 200 First Street S. W., Rochester, Minnesota 55905.
Case 1. Left: Contrast-enhanced computerized tomography scan demonstrating a 1-cm lesion in the mesial left temporal lobe. This has a typical appearance of aneurysms in this location with a contrast layer within a lumen surrounded by a peripheral rim without significant mass effect. In spite of this, conservative treatment was recommended. Right: Angiogram demonstrating a 3-cm giant aneurysm of the P2 segment of the posterior cerebral artery. This was treated by direct clipping of aneurysm neck.
Case 2. Photomicrograph of the aneurysm neck showing fragmentation and nearly total absence of both the internal elastic membrane (straight arrow) and muscularis layer (curved arrow), thickened intima (I), and adventitia with reactive fibrosis (A). ElVG, × 70.
Case 3. Left: Angiogram demonstrating a giant aneurysm of the internal carotid artery extending from the sphenoid sinus to the bifurcation. Right: Angiogram obtained after the carotid aneurysm was treated by cervical internal carotid artery ligation. Protection of hemispheric blood flow was insured through a superficial temporal-middle cerebral artery bypass. Intraoperative cerebral blood flow measured 40 ml/100 gm/min through the graft.
Case 3. Upper Left: Left vertebral angiogram obtained during evaluation of the giant carotid aneurysm demonstrating mild irregularity and dilatation of both the vertebral and basilar arteries. Upper Right and Lower Left: Angiograms obtained 2 years later demonstrating progression of the basilar dilatation into a giant bilobed aneurysm. The patient tolerated a 10-minute trial balloon-occlusion of the vertebral artery due to collateral flow from

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======= Instance Index 9539 =========
Input Text: Answer the following question given this paragraph: 

Gram-negative bacteria have a cell wall made of peptidoglycan, whereas Gram-positive bacteria have a cell wall made of lipoteichoic acid. Figure 22.19 Which of the following statements about the nitrogen cycle is false? a. Nitrogen fixing bacteria exist on the root nodules of legumes and in the soil. Denitrifying bacteria convert nitrates (NO3-) into nitrogen gas (N2). Ammonification is the process by which ammonium ion (NH4+) is released from decomposing organic compounds. Nitrification is the process by which nitrites (NO2-) are converted to ammonium ion (NH4+).


Q: Gram-negative bacteria have a cell wall made of peptidoglycan, whereas gram-positive bacteria have a cell wall made of what?

 Choices:

- lipoteichoic acid

- choanocyte acid

- solmization acid

- hydrolic acid

A:

Target Text: lipoteichoic acid

#### Retrieved Documents ####

Rank: 0
Score: 118.00865
Retrieved Text: A Bacterial cell under an electron microscope reveals many components, some of which are external to the cell wall and some are internal to the cell wall. Some of the structures are confined only to certain species and some other structures act as the characteristic features of certain species. Structures external to the cell wall include flagella, capsules and sheaths. Structures internal to the cell include cytoplasmic membrane and all other cytoplasmic inclusions.
Cell wall is a very rigid structure which provides support and gives shape to the cell. It is about 100-140 nm in thickness. Most of the bacteria live in hypotonic environments and tend to take up water due to the variation in the osmotic pressures between the bacterial cells and the existing environment. Hence, the main function of the cell wall is to prevent the cell from expanding and eventually bursting in the hypotonic environments. Bacterial cell has the ability to retain their original shape when subjected to very high pressures, due to the rigidity of the cell wall.
Cell wall is composed of two polymers, one consisting of saccharide subunits and the other consisting of amino acid subunits. Thus a bacterial cell wall is glycopeptide which is also known as peptidoglycan. The saccharide component of the cell wall has alternating repeating units of two amino sugars related to glucose. One of these two is NAM (N-Acetyl Muramic acid) and the other is NAG (N-Acetyl glucosamine). Both NAG and NAM form the back bone of the cell wall structure.
The alternating units of NAG and NAM

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Score: 116.265335
Retrieved Text: Cells build up stores of molecules required for growth inside the cell in higher amounts than are found outside the cell. Water naturally wants to flow into the cell to balance the number of molecules inside and outside, but if the cell were to allow this, it would burst like an overfilled balloon. The cell wall allows the cell to withstand this osmotic pressure.
In bacteria, the cell wall is made of peptidoglycan, a structure not found in either eukaryotes or archaea. This structure forms a meshlike sac around the cell and provides it with rigidity. Peptidoglycan is made up of polysaccharides linked by peptide bridges. Polysaccharides are long sugar chains of alternating N-acetylglucosamine (NAG) and N-acetylmuramic acid (NAM) units, which are firmly attached together by chemical bonds.
As shown, polysaccharides arrange like cables that encircle the cell and are connected by peptide bridges made of the four amino acids L-alanine, D-alanine, D-glutamic acid, and either lysine or diaminopimelic acid (DAP). Peptide bridges are covalently linked to NAM sugars. Each individual unit of peptidoglycan is, therefore, a NAG-NAM-tetrapeptide.
The peptide bridge can be made up of different amino acids and creates diversity in the peptidoglycan structure between bacteria.
Bacteria are classified as either Gram-positive or Gram-negative based on the results of the Gram-stain. Structural differences in peptidoglycan are the basis for this differentiation. Gram-positive bacteria retain the crystal violet stain in the Gram-stain procedure because they have a thick, multilayer sheet of peptidoglycan. Gram-negative bacteria, on the other hand, do not retain the crystal violet stain in the Gram-stain procedure

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Score: 102.13851
Retrieved Text: and functions in the presence or absence of O2.
in the cytoplasmic matrix of procaryotes and eucaryotes.
The pathway as a whole may be divided into two parts.
will soon be used to make ATP.
energy is captured as a glucose molecule is converted to two molecules of pyruvate.
3). Inclusion Bodies: There are granules of organic or inorganic materials. These bodies are generally for storage( Eg carbon compound, inorganic substance & energy) & also helps to osmotic pressure. Some of the inclusion bodies are poly-beta- hydroxy butyrate granules( carbon storage), some glucose(carbon storage), sulphur granules( sulphur storage), gas vacuoles( helps bacteria to regulate buoyancy & float), phosphate granules or volutin granules or meta chromatin granules( storage of phosphates).
2.) Cytoplasm: It refers to internal matrix of cell inside the cytoplasmic membrane. Prokaryotic cytoplasm lacks membrane bound structures . The cytoplasmic matrix is largely watered which dissolves proteins, amino acids, sugars, nucleotides, salts, vitamins, & ions. It also contains certain bacterial structures like inclusion bodies, nucleoid, plasmids.
A) Ribosomes: They are r-RNA protein bodies which give granular appearance. Proteins are synthesized in ribosomes & prokaryotic. Proteins are synthesized in ribosomes & prokaryotic ribosomes aren't bound to endoplasmic reticulum. Ribosomes of prokaryotes are called 70S(Sedimentation Coefficient) & are composed of 2 units(50S & 30S). Antibiotics such as Streptomycin &Tetracycline prevents bacterial ribosomes from carrying out protein synthesis.
1) Cytoplasmic membrane: It is a thick structure( 8 nm) that separates the cytoplasm from outer membrane. It is composed of phospholipid & protein. Phospholipid forms the bi layer in which protein( integral & peripheral) are held.
It acts

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Retrieved Text: The Gram-negative bacteria include most of the bacteria normally found in the gastrointestinal tract that can be responsible for disease as well as gonococci (venereal disease) and …... Increasing rates of drug resistance among gram-positive and gram-negative pathogens are being documented in many hospitals, including cancer treatment centers [8, 13, 18, 19, 20]. The most frequently isolated organisms are listed in table 2 .
Bacterial Classification Based on Staining MethodsBacteria are grouped as Gram positive and Gram negative bacteria, based on the results of Gram staining method, wherein an agent is used to bind to the cell wall of the bacteria.Gram positive bacteria - take up crystal violet dye and retain their blue or violet color.Gram negative bacteria - do not take up crystal violet dye, and thus appear... Gram Positive cocci are grouped together based on their gram stain reactions, thick cell wall composition, and spherical shape. Most of the organisms in these groups are members of the Micrococcaceae family.
A list of antibiotic resistant bacteria is provided below. Gram positive Clostridium difficile. Clostridium difficile is a nosocomial pathogen that causes diarrheal disease worldwide. Diarrhea caused by C. difficile can be life-threatening. Infections are most frequent in people who have had recent medical and/or antibiotic treatment. C. difficile infections commonly occur during... 15/10/2010 · Other Gram-positive bacteria, such as Streptococcus and Lactobacillus, which may occur in higher numbers than bifidobacteria, can inhibit their growth. Although selective media has been designed for the isolation of bifidobacteria from environmental waters, the outcome is still unsatisfactory, with appreciable numbers of

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Rank: 4
Score: 97.69834
Retrieved Text: Ampicillin is a version of penicillin that is able to last longer, resist stomach acid, and kill some gram-negative bacteria as well as the gram-positive bacteria. It is often used to prevent and treat infections found in cuts and wounds, the mouth, the upper respiratory system, and the bladder.
Bacteria often build resistance to this drug.
This drug works best if given 1 hour before feeding or 2 hours after. It may be given with food is stomach upset occurs.
The oral form of this drug is not absorbed very effectively, as with the injection or Amoxicillin.
Ampicillin kills bacteria by preventing them from building a proper cell wall while they grow. It accomplishes this by inhibiting the linking of peptidoglycan chains that are a major component in both gram-positive and some gram-negative bacteria’s cell walls.
Ampicillin sodium Injection should be used immediately after reconstitution.
DO NOT USE AMPICILLIN IN RABBITS, GUINEA PIGS, OR RODENTS.

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Rank: 5
Score: 95.12345
Retrieved Text: Peptidoglycan (also referred to as murein), an essential and specific component of the bacterial cell envelope, forms a mesh-like layer outside the cytoplasmic membrane, is responsible for rigidity and shape of bacterial cells and protects them from osmotic disruption. Indeed, any inhibition of its biosynthesis (mutation, antibiotic) or its specific degradation (e.g. by lysozyme) during cell growth will result in cell lysis. Peptidoglycan also contributes to the maintenance of a defined cell shape and serves as a scaffold for anchoring other cell envelope components such as proteins and teichoic acids. It is intimately involved in the processes of cell growth and cell division. It is a polymer that occurs in cell walls of both Gram-positive and Gram-negative bacteria but has not been found in Archaea. In Gram-positive bacteria it represents about 30-70% of the cell wall aside from polysaccharides, teichoic or teichuronic acids. It is only a minor component in Gram-negative cell walls that mainly consist of lipopolysaccharides and lipoproteins. The structure of peptidoglycan plays very important roles in investigating immune responses, the action of antibiotics and mechanisms of resistance, phage susceptibility and serological behavior, and for the classification and identification of bacteria.
Peptidoglycan is a heteropolymer that consists of glycan strands that are crosslinked by peptides. The glycan backbone is composed of alternating units of N-acetylglucosamine and N-acetylmuramic acid linked by β-1,4-glycosidic bonds. The peptide subunits usually contain four alternating L- and D-amino acids, and they are connected to the glycan stands via the lactyl groups of the N-acetylmuramic acid residues. Cross-linking of the glycan strands

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Rank: 6
Score: 91.70857
Retrieved Text: Antibiotics which inhibit bacterial peptidoglycan biosynthesis are the most widely used in current clinical practice. Nevertheless, resistant strains increase dramatically, with serious economic impact and effects on public health, and are responsible for thousands of deaths each year. Critical clinical situations should benefit from a rapid procedure to evaluate the sensitivity or resistance to antibiotics that act at the cell wall. We have adapted a kit for rapid determination of bacterial DNA fragmentation, to assess cell wall integrity.
Cells incubated with the antibiotic were embedded in an agarose microgel on a slide, incubated in an adapted lysis buffer, stained with a DNA fluorochrome, SYBR Gold and observed under fluorescence microscopy. The lysis affects the cells differentially, depending on the integrity of the wall. If the bacterium is susceptible to the antibiotic, the weakened cell wall is affected by the lysing solution so the nucleoid of DNA contained inside the bacterium is released and spread. Alternatively, if the bacterium is resistant to the antibiotic, it is practically unaffected by the lysis solution and does not liberate the nucleoid, retaining its normal morphological appearance. In an initial approach, the procedure accurately discriminates susceptible, intermediate and resistant strains of Escherichia coli to amoxicillin/clavulanic acid. When the bacteria came from an exponentially growing liquid culture, the effect on the cell wall of the β-lactam was evident much earlier that when they came from an agar plate. A dose-response experiment with an E. coli strain susceptible to ampicillin demonstrated a weak effect before the MIC dose. The cell wall damage was not

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Rank: 7
Score: 91.1297
Retrieved Text: What is 130 years old and can help you pass your FRCPath Part 2 exam?
Is it me or are Microbiology Registrars getting younger?
The first aspect of diagnostic microbiology I get the Registrars to start with is Gram staining and this got me thinking. In the age of automation, MaldiTOF and molecular diagnostics, does Gram’s stain still have a role in the microbiology laboratory? Why do I spend so much time teaching Registrars to become proficient at it? How does it help them in the FRCPath exams and is it still relevant in day-to-day clinical microbiology?
In 1884 a Danish scientist working in Berlin developed a method for distinguishing different types of bacteria viewed with a microscope. His name was Hans Christian Gram, and his technique is still in use in Microbiology laboratories today; the Gram’s stain.
In principal, Gram’s method for staining bacteria is pretty simple. Once the bacteria have been fixed to a glass slide by gentle heat (which stops them being washed off the slide when the staining liquids are added) there are only four main steps and in total it takes less than five minutes to perform a Gram’s stain.
The slide is flooded with crystal violet for about 30 seconds which enters in to bacterial cells. The crystal violet also forms positively charged particles inside the cell that bind to negatively charged components of the bacteria staining it purple.
Iodine is added to the slide for a further 30 seconds which binds to the intracellular crystal violet forming large particles; these become trapped inside the bacterial

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Rank: 8
Score: 90.38037
Retrieved Text: Penicillins, Cephalosporins, and Other β-Lactam Antibiotics. In: Hilal-Dandan R, Brunton LL. Hilal-Dandan R, Brunton L.L. Eds. Randa Hilal-Dandan, and Laurence L. Brunton.eds. Goodman and Gilman's Manual of Pharmacology and Therapeutics, 2e New York, NY: McGraw-Hill; . http://accesspharmacy.mhmedical.com/content.aspx?bookid=1810&sectionid=124495847. Accessed April 26, 2019.
. "Penicillins, Cephalosporins, and Other β-Lactam Antibiotics." Goodman and Gilman's Manual of Pharmacology and Therapeutics, 2e Hilal-Dandan R, Brunton LL. Hilal-Dandan R, Brunton L.L. Eds. Randa Hilal-Dandan, and Laurence L. Brunton. New York, NY: McGraw-Hill, , http://accesspharmacy.mhmedical.com/content.aspx?bookid=1810&sectionid=124495847.
The β-lactam antibiotics—penicillins, cephalosporins, and carbapenems—share a common structure and mechanism of action, inhibition of the synthesis of the bacterial peptidoglycan cell wall. Bacterial resistance against the β-lactam antibiotics continues to increase at a dramatic rate. β-Lactamase inhibitors such as clavulanate can extend the utility of these drugs against β-lactamase-producing organisms. Unfortunately, resistance includes not only production of β-lactamases but also alterations in or acquisition of novel penicillin-binding proteins (PBPs) and decreased entry and/or active efflux of the antibiotic. To a dangerous degree, we are re-entering the pre-antibiotic era, with many nosocomial gram-negative bacterial infections resistant to all available antibiotics.
MECHANISM OF ACTION: INHIBITION OF PEPTIDOGLYCAN SYNTHESIS. Peptidoglycan is a heteropolymeric component of the cell wall that provides rigid mechanical stability. The β-lactam antibiotics inhibit the last step in peptidoglycan synthesis (Figure 53-1).
Action of β-lactam antibiotics in Staphylococcus aureus. The bacterial cell wall consists of glycopeptide polymers (a NAM-NAG amino-hexose backbone) linked via bridges between amino acid side chains. In S. aureus, the bridge is (Gly)5-D-Ala between lysines. The cross-linking is catalyzed by a transpeptidase, the enzyme that penicillins and cephalosporins

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Rank: 9
Score: 90.16559
Retrieved Text: Please visit my Linkedin profile for up-to-date details.
My project focuses on exploiting proteins involved in bacteria growth as targets for novel antibiotics design, with particular emphasis placed on penicillin binding proteins (PBPs).
Virtually all bacteria species contain the essential cell wall polymer: peptidoglycan (murein). Its primary function is to protect the cell from effects of high internal osmotic pressure. Moreover, peptidoglycan maintains defined bacteria shape and is directly involved in its growth and division. Although numerous murein-affecting antibiotics have been discovered and developed, their efficiency drops due to an emergence of multiple drug resistant bacteria. Recently, the spread of resistant strains from the ‘ESKAPE’ group of organisms poses a significant threat to modern healthcare.
The scope of the project encompasses expression of penicillin binding proteins from various Gram-negative bacteria and their functional characterization using novel substrate dependent assays. Since PBPs are capable of performing two distinct steps of peptidoglycan synthesis (transglycosylation and transpeptidation), they are particularly valuable targets for bactericidal drugs. Their inhibition produces an imbalance in cell wall metabolism, resulting in growth suppression or lysis.
In order to elucidate enzymatic performance of particular members of the PBP family, quantitative assays need to be developed suitable for next generation drug discovery. I’m going to employ various fluoro- and radiolabelled peptidoglycan precursors to produce methods for the rational design of novel peptidoglycan synthesis inhibitors.
Bachelor thesis: “Molecular diagnostics of human papillomaviruses infections”.

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Rank: 10
Score: 89.71385
Retrieved Text: Enzyme for specific lysis of the cell wall of Staphylococcus bacteria. Form: solution. Concentration 0,4 U/µl.
Enzyme for lysis of Gram-negative and Gram-positive bacteria. Form: solution. Concentration 10 mg/ml.
Mix of enzymes for efficient lysis of yeast cell wall. Form: lyophilisate.
Mix of enzymes for efficient lysis of yeast cell wall. Form: solution. Concentration 10 U/µl.
Enzyme for digesting the cell wall of Gram-positive bacteria especially resistant to lysis. Including: Streptococcus, Enterococcus, Lactobacillus, Lactococcus and Listeria. Form: lyophilisate, activity > 3000 - 4000 U/mg.
Enzyme for digesting the cell wall of Gram-positive bacteria especially resistant to lysis. Including: Streptococcus, Enterococcus, Lactobacillus, Lactococcus and Listeria. Form: solution, concentration 10 U/µl.
Enzyme for digesting proteins in biological samples. Form: lyophilisate, activity ≥ 35 U/mg.
Enzyme for digesting proteins in biological samples. Form: solution, concentration 20 mg/ml, activity ≥ 30 U/mg.

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Rank: 11
Score: 86.212364
Retrieved Text: any of a large group of natural or semisynthetic antibacterial antibiotics derived directly or indirectly from strains of fungi of the genus Penicillium and other soil-inhabiting fungi grown on special culture media. Penicillins exert a bacteriocidal as well as a bacteriostatic effect on susceptible bacteria by interfering with the final stages of the synthesis of peptidoglycan, a substance in the bacterial cell wall. Despite their relatively low toxicity for the host, they are active against many bacteria, especially gram-positive pathogens (streptococci, staphylococci, pneumococci); clostridia; certain gram-negative forms (gonococci and meningococci); certain spirochetes (Treponema pallidum and T. pertenue); and certain fungi. Certain strains of some target species, for example staphylococci, secrete the enzyme penicillinase, which inactivates penicillin and confers resistance to the antibiotic. Some of the newer penicillins, such as methicillin, are more effective against penicillinase-producing organisms. A class of extended-spectrum penicillins includes piperacillin and mezlocillin.
Penicillin is administered intramuscularly, orally, in liquid or tablet form, and topically in ointments. Oral administration requires larger doses of the drug because absorption is incomplete. Allergic reactions occur in some persons. The reaction may be slight—a stinging or burning sensation at the site of injection—or it can be more serious—severe dermatitis or even anaphylactic shock, which may be fatal.
penicillin G the most widely used penicillin, used principally in the treatment of infections due to gram-positive organisms, gram-negative cocci, Treponema pallidum and Actinomyces israelii. The usual forms are salts such as penicillin benzathine, potassium, procaine, or sodium. Called also benzylpenicillin.
penicillin V a biosynthetically or semisynthetically produced antibiotic similar to penicillin g, used

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Rank: 12
Score: 85.008606
Retrieved Text: To physicists, bacteria are beautiful little organisms to study because of their (relative) simplicity. They mostly come in conveniently shaped cylindrical or spherical single cells, and the organization of the cells are simple, at least compared to eukaryotic cells: there’s an inside, with all of the goo necessary for life, and a surface, which of course has a membrane, which distinguishes the inside of the cell from the outside, and a cell wall, which acts like an exoskeleton to provide mechanical integrity to the cell. But what’s going on with Gram-negative bacteria – these little guys have two membranes? Why? This is the kind of “Talmudic Question,” as Elio Schaecter might say, that furrowed my brow when I came to bacteriology from physics.
The outer membrane has always been an enigmatic structure, and indeed our understanding of it as a structure has always lagged behind our understanding of its chemical composition, which in turn lagged behind our understanding of it as “something” that engaged the human immune system. Around the turn of the 20th century, the German physician-scientist Richard Pfeiffer found that heat-stable toxins associated with the cell (i.e., not soluble, secreted molecules) could actually kill Guinea pigs even when the bacteria themselves were dead. He termed this putative substance “endotoxin.” The “agglutinins” were discovered thereafter, and during the next several decades, the various types of antibody/antigen interactions were characterized (e.g., O- versus H-agglutination), but it wasn’t until the 1930’s before the O-antigen was found to be a component of lipopolysaccharide.
Keep in mind, though, that we were

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Rank: 13
Score: 82.78641
Retrieved Text: Our laboratory examines the mechanisms and strategies whereby pathogenic bacteria cause human disease. Several different microbes are being investigated.
The cell wall of Staphylococcus aureus and other Gram-positive pathogens can be viewed as a surface organelle with anchored proteins that interact with the host environment during infection. Our research has revealed four different mechanisms of protein anchoring to the cell wall envelope. Surface proteins bearing a C-terminal sorting signal with a LPXTG motif are cleaved by the sortase A enzyme and linked to the cell wall crossbridges of peptidoglycan. This group of surface proteins is essential for pathogenesis and mediates bacterial attachment to host tissues and escape from the immune system. Surface proteins bearing a C-terminal sorting signal with a NPQTN motif are cleaved by sortase B. This mechanism is involved in iron transport during infection and is required for bacterial persistence in the host. Autolysins are enzymes that cleave the cell wall envelope at defined sites. One group of autolysins, e.g. lysostaphin and f11 hydrolase, is targeted to a receptor that is distributed uniformly over the bacterial surface. Another autolysins is targeted to the equatorial surface rings of staphylococci and mediates peptidoglycan cleavage at cell divisions sites. Our laboratory entertains genetic, molecular biological, biochemical, microscopic as well as animal infectious strategies to reveal mechanisms of protein targeting and the role in the establishment of disease. Our results are useful for the design of new therapies that can be used for the treatment of human infections caused by S. aureus and other Gram-positive bacteria.
Pathogenic Yersinia spp. invade

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Rank: 14
Score: 82.77938
Retrieved Text: Microscopy refers to the practice that involves the use of a microscope for the purposes of observing small scale structures that cannot be viewed using the naked eye and often cell staining is necessary as structures are difficult to discern due to insufficient contrast.
Cell staining is a technique used for the main purpose of increasing contrast through changing the color of some of the parts of the structure being observed thus allowing for a clearer view. There are a variety of microscopic stains that can be used in microscopy.
First of all, staining can be in-vivo or in-vitro. The difference between these is that whereas In-vivo staining refers to the staining of a biological matter while it is still alive, in-vitro staining refers to a staining technique where the biological matter is non-living.
The following are common stains explaining techniques, preparations and procedures for each.
These are two stains used in the examination of thin slices of biological tissue. Contrast is created by the stains where Haematoxylin turns the nuclei blue while eosin turns the cytoplasm as well as other parts pink or red.
4- Add 1 gram of crystal.
Whereas alum is the mordant, thymol prevents fungal growth.
1- Measure 10 grams of eosin crystals and add to mix in 1000ml of hot tap water (70- 80 degrees). This should be mixed to dilute and stored in a dark flask. This can be used directly.
ACCUMATE differentiating solution is made ready for use. A substitute of Scott's Tap water is prepared through mixing a part of Scott's Tap water substitute concentrate with

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Retrieved Text: Ampicillin salt is an antibiotic that inhibits bacterial cell-wall synthesis. Active against Gram-negative bacteria. Inactivated by lactamases. Suitable for use in research that uses ampicillin-resistant plasmids.
Overview A β-lactam antibiotic that inhibits bacterial cell-wall synthesis. Active against Gram-negative bacteria. Inactivated by lactamases. Suitable for use in research that uses ampicillin-resistant plasmids.
Special Instructions Following reconstitution, aliquot and freeze (-20°C). Aqueous stock solutions are stable for up to 1 month at -20°C. Product is heat-resistant and stable between pH 2 and 11.
Description Kills growing cells by interfering with the terminal reaction in bacterial wall synthesis. Active against Gram-negative bacteria. Inactivated by lactamases. Suitable for use in research that uses ampicillin-resistant plasmids.

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Retrieved Text: Drosophila melanogaster has emerged as a powerful model system to study innate immunity. Insects employ multilayered innate immune defenses including antimicrobial peptide responses and phagocytosis. In Drosophila, phagocytosis is carried out by plasmatocytes, a blood cell type similar to mammalian macrophages and neutrophils. The scavenger receptor Eater is expressed by larval and adult plasmatocytes and mediates recognition of a broad range of bacterial pathogens. Eater is required for fly survival after infection with Gram-positive and Gram-negative bacteria. However, the bacterial ligands of Eater, and the mechanisms by which this receptor recognizes these different types of bacteria, remain poorly understood. To address this problem, I generated a soluble, Fc-tagged receptor variant of Eater comprising the N-terminal 199 amino acids (including four N-terminal EGF-like repeats) and raised antibodies against Eater. Using these tools, I established (i) that Eater is expressed on the surface of macrophage-like Drosophila S2 cells, (ii) that it interacts with broad, yet distinct classes of heat- and ethanol-inactivated microbes and (iii) that it binds peptidoglycan from Gram-negative Proteobacteria (E. coli) and Gram-positive Firmicutes (E. faecalis and S. aureus), but not Gram-positive Actinobacteria (M. luteus). In order to identify genes involved in the phagocytosis of M. luteus, I screened 39 candidate genes by RNA interference-mediated knock down in S2 cells. A longstanding question was whether Eater recognizes live, naïve bacteria. I found that Eater-Fc bound equally well to naïve or heat-inactivated S. aureus or E. faecalis, suggesting that in vivo Eater directly targets live Gram-positive bacteria, enabling their phagocytic clearance and destruction. By contrast, Eater-Fc was

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Retrieved Text: Moraxella (Branhamella) catarrhalis: Gram-negative aerobic cocci of low virulence that colonize the nasopharynx and occasionally cause MENINGITIS; BACTEREMIA; EMPYEMA; PERICARDITIS; and PNEUMONIA.Moraxella: A genus of gram-negative, aerobic bacteria occurring as rods (subgenus Moraxella) or cocci (subgenus Branhamella). Its organisms are parasitic on the mucous membranes of humans and other warm-blooded animals.Neisseriaceae: A family of gram-negative, parasitic bacteria including several important pathogens of man.Neisseria: A genus of gram-negative, aerobic, coccoid bacteria whose organisms are part of the normal flora of the oropharynx, nasopharynx, and genitourinary tract. Some species are primary pathogens for humans.Neisseriaceae Infections: Infections with bacteria of the family NEISSERIACEAE.Moraxella (Moraxella) bovis: A species of gram-negative, aerobic bacteria that is most frequently isolated from bovine eyes in cases of infectious keratoconjunctivitis (KERATOCONJUNCTIVITIS, INFECTIOUS), but also occurs in unaffected eyes and the nasal cavity of cattle.Moraxellaceae Infections: Infections with bacteria of the family MORAXELLACEAE.Anthracosilicosis: A form of pneumoconiosis caused by inhalation of dust that contains both CARBON and crystalline SILICON DIOXIDE. These foreign matters induce fibrous nodule formation in the lung.Respiratory Tract Infections: Invasion of the host RESPIRATORY SYSTEM by microorganisms, usually leading to pathological processes or diseases.Haemophilus influenzae: A species of HAEMOPHILUS found on the mucous membranes of humans and a variety of animals. The species is further divided into biotypes I through VIII.TracheitisCefmetazole: A semisynthetic cephamycin antibiotic with a broad spectrum of activity against both gram-positive and gram-negative microorganisms. It has a high rate of efficacy in many types of infection and to date no severe side effects have been noted.Bacterial Infections: Infections by bacteria,

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Retrieved Text: Commonly referred to as E. coli, Escherichia coli is a bacterium that is typically found in a number of environments including various foods, soil and animal intestines. E. coli is very diverse and belongs to the genus Escherichia. While most of the strains of E. coli are harmless (and also important in the human intestinal tract), others are harmful and can cause very serious health implications. A good example of this is E coli 0157:H7.
In the intestinal tract, E coli plays an important role in that it aids in digestion and supports the absorption of vital vitamins from food in the body. In addition, E coli has been shown to be beneficial in that it prevents the growth and proliferation of other harmful species of bacteria that would otherwise cause health problems.
Main Category of Pathogenic (Diarrheagenic) E. Coli.
E. coli is described as a Gram-negative bacterium. This is because they stain negative using the Gram stain.
The Gram stain is a differential technique that is commonly used for the purposes of classifying bacteria. The staining technique distinguishes between two main types of bacteria (gram positive and gram negative) by imparting color on the cells.
Being Gram-negative bacteria, E. coli have an additional outer membrane that is composed of phospholipids and lipopolysaccharides. The presence lipopolysaccharides on the outer membrane of bacteria gives it an overall negative charge to the cell wall. Because of these properties, E. coli does not retain crystal violet during the Gram staining process.
To determine whether a strain (s) of E. coli is present in a sample,

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Retrieved Text: Meticillin (INN, BAN) or methicillin (USAN, AAN) is a narrow-spectrum β-lactam antibiotic of the penicillin class. It should not be confused with the antibiotic metacycline. In 2005, the name of the drug was changed from methicillin to meticillin in accordance with the International Pharmacopoeia guidelines.
Meticillin is no longer used to treat patients. Compared to other β-lactamase-resistant penicillins, it is less active, can be administered only parenterally, and has a higher frequency of interstitial nephritis, an otherwise-rare side effect of penicillins. However, selection of Meticillin depended on the outcome of susceptibility test of the microorganism, since it is no longer produced, it is also not routinely tested any more. It also served a purpose in the laboratory to determine the antibiotic sensitivity of Staphylococcus aureus to other β-lactamase-resistant penicillins; this role has now been passed on to other penicillines, namely Cloxacillin as well as genetic testing for the presence of mecA gene by PCR.
At one time, meticillin was used to treat infections caused by certain Gram-positive bacteria including Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus pyogenes, and Streptococcus pneumoniae. Today, meticillin is not as effective against these organisms due to resistance.
Resistance to meticillin is conferred by activation of a new bacterial PBP gene (mecA). This encodes protein PBP2a. PBP2a works in a similar manner to other PBPs, but it binds β-lactams with very low affinity, meaning they do not compete efficiently with the natural substrate of the enzyme and will not inhibit cell wall biosynthesis. Expression of PBPA2 confers resistance to all β-lactams.
Like other beta-lactam antibiotics, meticillin acts by

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Retrieved Text: A β-lactam antibiotic that inhibits bacterial cell-wall synthesis. Sterilized by γ-irradiation. Potency: ≥ 845 µg/mg.
Overview A β-lactam antibiotic that inhibits bacterial cell-wall synthesis. Sterilized by γ-irradiation. Potency: ≥ 845 µg/mg.
Description Antibiotic that kills bacteria by interfering with the terminal reaction in bacterial wall synthesis. Effective against gram-negative bacteria. Ampicillin is ineffective against Pseudomonas, Enterobacter, and indole-positive Proteus infections. Sterilized by γ-irradiation.
Solubility Reconstitute in 20 ml sterile H₂O to yield a final stock concentration of 10 mg/ml.

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Retrieved Text: What Is the Evolutionary Origin of the Mycobacterial Cell Envelope?
The Mycobacterial Cell Envelope: A Relict From the Past or the Result of Recent Evolution?
Mycobacteria are well known for their taxonomic diversity, their impact on global health, and for their atypical cell wall and envelope. In addition to a cytoplasmic membrane and a peptidoglycan layer, the cell envelope of members of the order Corynebacteriales, which include Mycobacterium tuberculosis, also have an arabinogalactan layer connecting the peptidoglycan to an outer membrane, the so-called “mycomembrane.” This unusual cell envelope composition of mycobacteria is of prime importance for several physiological processes such as protection from external stresses and for virulence. Although there have been recent breakthroughs in the elucidation of the composition and organization of this cell envelope, its evolutionary origin remains a mystery. In this perspectives article, the characteristics of the cell envelope of mycobacteria with respect to other actinobacteria will be dissected through a molecular evolution framework in order to provide a panoramic view of the evolutionary pathways that appear to be at the origin of this unique cell envelope. In combination with a robust molecular phylogeny, we have assembled a gene matrix based on the presence or absence of key determinants of cell envelope biogenesis in the Actinobacteria phylum. We present several evolutionary scenarios regarding the origin of the mycomembrane. In light of the data presented here, we also propose a novel alternative hypothesis whereby the stepwise acquisition of core enzymatic functions may have allowed the sequential remodeling of the external cell membrane during the evolution of

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Retrieved Text: Prokaryotes were the first kind of organisms to evolve. They are single-celled organisms that don’t have a well-defined nucleus and also lack other membrane-bound organelles such as mitochondria. The genetic material in prokaryotic cells exists within an irregularly shaped area of the cell known as the nucleoid.
All water-soluble components within prokaryotes such as DNA, proteins and metabolites are found in the cytoplasm, enclosed within the cell membrane and not in separate compartments of the cell. However, bacteria have protein-based micro-compartments that behave like basic organelles within protein shells.
The two types of prokaryotic cell are Archaea and bacteria. Prokaryotes have a cytoplasm, plasma membrane, DNA, and ribosomes, but no nucleus. They have a cell wall that offers an additional layer of protection, prevents dehydration and maintains the shape of the cell. The cell wall is made of peptidoglycan. Some prokaryotic cells also have a polysaccharide layer, referred to as a capsule, that enables specific attachment of the cell to certain surfaces.
Prokaryotes have a plasma membrane, which separates intracellular components from the external environment. Prokaryotic cytoplasm is made up of a jelly-like substance called the cytosol, in which cell components are contained.
As is the case for all cells, bacteria have a cytoskeleton, a network of filaments and tubules that provides structural support and maintains the shape of the cell. The cytoskeleton also forms a whip-like, external structure called the flagella, which the cell uses to move from one place to another (locomotion). Thin, hair- like structures called pili are also found in some bacteria, which aid in adhesion

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Retrieved Text: Aztreonam is a beta-lactam antibiotic resistant to beta-lactamases and indicated for Gramnegative infections including infections of the respiratory tract, urinary tract, blood, skin, and abdomen, as well as gynecological infections. Aztreonam is a bactericidal agent that acts by inhibition of bacterial cell wall synthesis. Aztreonam has activity in the presence of some beta-lactamases, both penicillinases and cephalosporinases, of Gram-negative and Gram-positive bacteria.

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Retrieved Text: Production of outer membrane vesicles (OMV) that are secreted from the cellular surface is a ubiquitous phenomenon observed in all Gram-negative bacteria. These nanoparticles have been implicated in host-pathogen interactions, antibiotic resistance and dissemination of genetic elements. We have in our investigations focused our efforts on understanding the role of OMVs in cell envelope remodelling. Our combined proteomics and molecular biological data show that proteins that are imperative for outer membrane stability and uptake of essential co-factors are excluded from the OMV cargo, whereas proteins involved in host immune modulation and cell wall-synthesis regulation are secreted via vesiculation. Our findings indicate that bacteria, in the absence of sophisticated regulatory machineries at their surface, use cargo-sorted vesiculation as a mean to regulate the physiologically vital content of the outer membrane.

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Retrieved Text: Used to treat infections caused by susceptible Gram-positive bacteria, particularly beta-lactamase-producing organisms such as Staphylococcus aureus that would otherwise be resistant to most penicillins.
Meticillin (INN, BAN) or methicillin (USAN) is a narrow spectrum beta-lactam antibiotic of the penicillin class. It is no longer clinically used. Its role in therapy has been largely replaced by flucloxacillin and dicloxacillin, however the term methicillin-resistant Staphylococcus aureus (MRSA) continues to be used to describe Staphylococcus aureus strains resistant to all penicillins.
Like other beta-lactam antibiotics, meticillin acts by inhibiting the synthesis of bacterial cell walls. It inhibits cross-linkage between the linear peptidoglycan polymer chains that make up a major component of the cell wall of Gram-positive bacteria. It does this by binding to and competitively inhibiting the transpeptidase enzyme used by bacteria to cross-link the peptide (D-alanyl-alanine) used in peptidogylcan synthesis.
(R)-warfarin Meticillin may increase the anticoagulant activities of (R)-warfarin.
(S)-Warfarin Meticillin may increase the anticoagulant activities of (S)-Warfarin.
4-hydroxycoumarin Meticillin may increase the anticoagulant activities of 4-hydroxycoumarin.
Acemetacin Acemetacin may decrease the excretion rate of Meticillin which could result in a higher serum level.
Acenocoumarol Meticillin may increase the anticoagulant activities of Acenocoumarol.
Adenovirus type 7 vaccine live The therapeutic efficacy of Adenovirus type 7 vaccine live can be decreased when used in combination with Meticillin.
Alcuronium The therapeutic efficacy of Alcuronium can be increased when used in combination with Meticillin.
Amikacin The serum concentration of Amikacin can be decreased when it is combined with Meticillin.
Anthrax immune globulin human The therapeutic efficacy of Anthrax immune globulin human can be decreased when used in combination with Meticillin.
Anthrax vaccine The

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Retrieved Text: Amoxi-Tabs - Pfizer Animal Health is a semisynthetic amoxicillin antibiotic with a broad spectrum of activity. It provides bactericidal activity against a wide range of common gram-positive and gram-negative pathogens. For use in dogs and cats only.
ACTION: Amoxi-Tabs is stable in the presence of gastric acid and may be given without regard to meals. It is rapidly absorbed after oral administration. It diffuses readily into most body tissues and fluids with the exception of brain and spinal fluid, except when meninges are inflamed. Most of the amoxicillin is excreted unchanged in the urine.
Amoxicillin is similar to ampicillin in its bactericidal action against susceptible organisms. It acts through the inhibition of biosynthesis of cell wall mucopeptide. In vitro and/or in vivo studies have demonstrated the susceptibility of most strains of the following gram-positive and gram-negative bacteria: ?- and ?-haemolytic streptococci, nonpenicillinase-producing staphylococci, Streptococcus faecalis, Escherichia coli, and Proteus mirabilis. Because it does not resist destruction by penicillinase, it is not effective against penicillinase-producing bacteria, particularly resistant staphylococci. All strains of Pseudomonas and most strains of Klebsiella and Enterobacter are resistant.
HOW SUPPLIED: Amoxi-Tabs are supplied in 5 strengths: 50 mg, 100 mg, 150 mg, and 200 mg in bottles of 500 tablets; 400 mg in bottles of 250 tablets.

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Retrieved Text: Both Fimbria (plural Fimbriae) and Flagellum (plural flagella) are the filamentous proteinaceous structures found on the surface of some bacterial cells.
Fimbriae definition: Fimbriae are bristle like short fibres occurs on the surface of some Gram positive and Gram negative bacteria. Fimbriae enable the bacterial cell to stick to the surface of host cells. They also help in the formation of pellicles or biofilms. (Pellicle: thin sheet of cells on the surface of a liquid).
Flagella definition: Bacterial flagella are long whip like filamentous structures present in some bacteria. The most important function of flagella is to assist in locomotion. Flagella can also act as a sensory organ to detect temperature and the presence of certain chemicals in the external environment of the cell. Even though the flagella are present in prokaryotes and eukaryotes, both are entirely different in their structure and formation and mechanism of propulsion.
The present post describes the Similarities and Differences between Fimbriae and Flagella of bacteria with a Comparison Table.
Ø Both fimbriae and flagella are filamentous structures.
Ø Both are present in Gram positive and Gram negative bacteria.
Ø Both are cell surface appendages, present on the cell surface of bacteria.

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Retrieved Text: [2016-11-14] Release of vesicles from the outer membrane are known to play an important role in the biology of Gram-negative bacteria. They are relevant for pathogenesis and interaction of the bacteria with their environment. Only recently was it observed that membrane vesicles (MVs) also can be released from Gram-positive bacteria which lack an outer membrane and have a thick cell wall. The composition and mechanisms which govern the MV formation in Gram-positive bacteria was still unclear. Now, a new study, published in mBio, a high impact journal of the American Society for Microbiology, shows new findings on the composition and the regulation of MVs production in the Gram-positive, human pathogen, Group A streptococcus.
Electron microscopic picture of membrane vesicles (arrows) and Group A streptococcus (GAS) cells Group A streptococcus (GAS) is causing more than a half million peoples’ deaths every year. The infection is dependent on virulence proteins which are released through a secretory pathway. In a new study, headed by MIMS group leaders Emmanuelle Charpentier and Sun Nyunt Wai, postdocs Ulrike Resch and James Tsatsaronis and their colleagues found that virulence associated proteins and RNAs are abundant also in membrane vesicles released from GAS.
The scientists found MVs both in the cell wall surface and in the near vicinity of the bacterial cells (figure 1). The further analyses showed that the vesicle production is regulated by a two-component regulator which is virulence-associated.
“We know that membrane vesicles are produced by bacteria to defend themselves against inflammatory responses of the host cells”, Sun Nyunt Wai explained. “The two component

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Retrieved Text: Penicillin was discovered and developed as the first widely-used anti-microbial (antibiotic) agent in 1928. Ever since that time, bacteria have developed resistance to a wide range of antibiotics as they have been introduced. This capability can be explained based on two important properties of bacteria. These organisms divide approximately every twenty minutes; therefore, through the course of a single twenty-four hour day, seventy-two generations have been produced. If bacteria are in an environment permeated with antibiotic some of the progeny may develop a resistance due to a spontaneous mutation in their genetic material (DNA). If this should happen, all the susceptible bacteria will die off leaving behind those that are resistant. This process can be regarded as natural selection. Since resistance is conferred by a change in the genetic makeup of the organism, resistance can then be passed on to all the progeny. There has always been a potential public health risk in regard to this ability of microorganisms to become resistant to these agents.
Bacteria are classified into two distinct groups – gram-negative and gram-positive. This classification was created based on their ability or inability to take up a particular stain. A well known example of gram-positive bacteria that is disease producing (pathogenic) is Staphylococcus aureus that is of a particular concern in a hospital setting. An antibiotic that has been traditionally used to combat this kind of infection is methicillin. As a result of its universal application, a highly resistance form of this bacteria referred to as methicillin resistant Staphylococcus aureus (MRSA) has arisen. This

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======= Instance Index 8119 =========
Input Text: Answer the following question given this paragraph: 

Chloroplasts Like the mitochondria, chloroplasts have their own DNA and ribosomes, but chloroplasts have an entirely different function. Chloroplasts are plant cell organelles that carry out photosynthesis. Photosynthesis is the series of reactions that use carbon dioxide, water, and light energy to make glucose and oxygen. This is a major difference between plants and animals; plants (autotrophs) are able to make their own food, like sugars, while animals (heterotrophs) must ingest their food. Like mitochondria, chloroplasts have outer and inner membranes, but within the space enclosed by a chloroplast’s inner membrane is a set of interconnected and stacked fluid-filled membrane sacs called thylakoids ( Figure 4.17). Each stack of thylakoids is called a granum (plural = grana). The fluid enclosed by the inner membrane that surrounds the grana is called the stroma.


Q: Like the mitochondria, chloroplasts have their own dna and ribosomes, but chloroplasts have an entirely different function. chloroplasts are plant cell organelles that carry out what?

 Choices:

- photosynthesis

- reproduction

- digestion

- growth

A:

Target Text: photosynthesis

#### Retrieved Documents ####

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Retrieved Text: The chloroplast, found only in algal and plant cells, is a cell organelle that produces energy through photosynthesis. The word chloroplast comes from the Greek words khloros, meaning “green”, and plastes, meaning “formed”. It has a high concentration of chlorophyll, the molecule that captures light energy, and this gives many plants and algae a green color. Like the mitochondrion, the chloroplast is thought to have evolved from once free-living bacteria.
Chloroplasts are the part of plant and algal cells that carry out photosynthesis, the process of converting light energy to energy stored in the form of sugar and other organic molecules that the plant or alga uses as food. Photosynthesis has two stages. In the first stage, the light-dependent reactions occur. These reactions capture sunlight through chlorophyll and carotenoids to form adenosine triphosphate (ATP, the energy currency of the cell) and nicotinamide adenine dinucleotide phosphate (NADPH), which carries electrons. The second stage consists of the light-independent reactions, also known as the Calvin cycle. In the Calvin cycle, the electrons carried by NADPH convert inorganic carbon dioxide and to an organic molecule in the form of a carbohydrate, a process known as CO2 fixation. Carbohydrates and other organic molecules can be stored and used at a later time for energy.
Chloroplasts are essential for the growth and survival of plants and photosynthetic algae. Like solar panels, chloroplasts take light energy and convert it into a usable form that powers activities. However, a few plants no longer have chloroplasts. One example is the parasitic plant genus Rafflesia, which obtains its

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Retrieved Text: Which organelles have their own DNA and protein. What organelle contains its own DNA and ribosomes. Mitochondria because it's a separate bateria that somehow merged with the cell's in a mutualistic form. Their membrane proteins are made not by the ER, but by free ribosomes in the cytosol and by ribosomes contained within the mitochondria and chloroplasts themselves.
SummaryQuia Cell Organelles and Functions Copy this to my account E-mail to a friend Find other activities Match the cell organelle with the correct function.
Organelles are membrane-bound subunits within a cell -- analogous to organs in the body -- that perform specific functions. Match the cell organelle with the correct function. Which are the organelles in a cell that contain DNA. The plant would gain energy in the form of ATP, while the bacteria it's thought that chloroplasts were once cyanobacteria gains a safe environment with ample light for it to live. In plant cells, mitochondria and chloroplast have their own DNA and ribosomes. To do this on most router models you have to press the reset button of the router for appr.
It is this DNA that programs the synthesis of the proteins made on the. All lifeform have it's own DNA in order to reproduce. Follow the instructions on the screen to install E-DiagTools. The nucleus is the control center of the cell, and houses genetic information. A molecule of deoxyribonucleic acid DNA consists of a long series of sugar nucleotide. HDR captures the scene and subject as we see it.

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Retrieved Text: Our natural world also utilizes the principle of form following function, especially in cell biology, and this will become clear as we explore eukaryotic cells ( [link]). Unlike prokaryotic cells, eukaryotic cells have: 1) a membrane-bound nucleus; 2) numerous membrane-bound organelles such as the endoplasmic reticulum, Golgi apparatus, chloroplasts, mitochondria, and others; and 3) several, rod-shaped chromosomes. Because a eukaryotic cell’s nucleus is surrounded by a membrane, it is often said to have a “true nucleus.” The word “organelle” means “little organ,” and, as already mentioned, organelles have specialized cellular functions, just as the organs of your body have specialized functions.
Like prokaryotes, eukaryotic cells have a plasma membrane ( [link]), a phospholipid bilayer with embedded proteins that separates the internal contents of the cell from its surrounding environment. A phospholipid is a lipid molecule with two fatty acid chains and a phosphate-containing group. The plasma membrane controls the passage of organic molecules, ions, water, and oxygen into and out of the cell. Wastes (such as carbon dioxide and ammonia) also leave the cell by passing through the plasma membrane.
The plasma membranes of cells that specialize in absorption are folded into fingerlike projections called microvilli (singular = microvillus); ( [link]). Such cells are typically found lining the small intestine, the organ that absorbs nutrients from digested food. This is an excellent example of form following function.
The cytoplasm is the entire region of a cell between the plasma membrane and the nuclear envelope (a structure to be discussed shortly). It is made up of organelles suspended in the

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Retrieved Text: | „.led to the evolution of modern eukaryotic cells with mitochondria and chloroplasts.
^ The aerobic endosymbiont evolved into mitochondria.
A 20.7 The endosymbiotic theory proposes that mitochondria and chloroplasts in eukaryotic cells arose from eubacteria. An original ancestral cell gave rise to prokaryotic and eukaryotic cells.
Chloroplasts and mitochondria are in many ways similar to bacteria. This resemblance is not superficial; indeed there is compelling evidence that these organelles evolved from eubacteria (see p. 000 in Chapter 2). The endosymbiotic theory (IFigure 20.7) proposes that mitochondria and chloroplasts were once free-living bacteria that became internal inhabitants (endosymbionts) of early eukaryotic cells. According to this theory, between 1 billion and 1.5 billion years ago, a large, anaerobic eukaryotic cell engulfed an aerobic eubacterium, one that possessed the enzymes necessary for oxidative phosphorylation. The eubacterium provided the formerly anaerobic cell with the capacity for oxidative phosphorylation and allowed it to produce more ATP for each organic molecule digested. With time, the endosymbiont became an integral part of the eukaryotic host cell, and its descendants evolved into present-day mitochondria. Sometime later, a similar relation arose between photosynthesizing eubacteria and eukaryotic cells, leading to the evolution of chloroplasts.
A great deal of evidence supports the idea that mitochondria and chloroplasts originated as eubacterial cells. Many modern, single-celled eukaryotes (protists) are hosts to endosymbiotic bacteria. Mitochondria and chloroplasts are similar in size to present-day eubacteria and possess their own DNA, which has many characteristics in common with eubacterial DNA. Mitochondria and chloroplasts possess ribosomes, some of which are similar in size and structure to

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Retrieved Text: using examples from typical plant, animal, fungi and bacteria cells.
All living things are made of cells. The cell is the basic unit of life. But, what is a cell made of? Lots of things. Every cell consists of an intricate system of different structures which all work together to allow the cell to function. You will already know some of these structures and what they do, but in this topic we're going to take this much further.
We'll use the 2D cut-through cell diagrams you're used to to help explain where these structures are, what they look like and what they do. However, don't forget that cells exist in 3D and not only that, their structures move!
Animal cells have many different structures depending on their function. However, first we'll consider what the typical structures of most animal cells are. You already know that animal cells consist of a cell membrane, nucleus and a fluid cytoplasm. In this course you need to learn more about the functions of the cell membrane and the nucleus. You also need to learn about two other organelles which are found in the cytoplasm of animal cells.
Cytoplasm: The cytoplasm is the liquid part of the cell. It consists mainly of water and has many different substances dissolved in it. Many of the cell's chemical reactions occur in the cytoplasm.
Cell membrane: The cell membrane contains the contents of the cell and provides a barrier to control what enters and leaves the cell. The cell membrane is often described as "selectively permeable" as it allows

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Retrieved Text: Plant cell structure is not included in all health science subjects (e.g. all courses in anatomy & physiology) but is is an important part of general biology. Basic cell biology is included in UK A-Level Biology and equivalent courses. It is also useful general knowledge for anyone working in life sciences. This page helps with the task: With the help of a diagram describe the structure of a plant cell.
Note: The diagram above is a general plant cell - so not a particular part of any specific plant. The labels in pink are links to pages of further information about the part of the plant cell indicated. The structures are not necessarily drawn to scale but in enough detail to aid recognition and to help students re-draw this diagram by hand to include in study notes or homework.
The structure of plant cells has similarities and differences compared with the structure of animal cells. The following table lists the parts of plant cells shown in the diagram above with brief notes about each of the structures types of organelles in plant cells.
Plant cells have cell walls - as compared with animal cells which do not have cell walls, and prokaryotic cells (bacteria) which do have cell walls but they are of a different construction than those of plant cells.
The main functions of plant cell walls are mechanical. Plant cell walls form part of a transport system called the apoplast system via which water and some solutes can pass through plant tissue via apoplastic pathways (along / through

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Retrieved Text: The cell. 6. Cholorplasts. Atlas of plant and animal histology.
Chloroplasts are organelles found in plant cells.
Chloroplasts are composed of outer membrane, inner membrane, intermembrane space between them, inner space, referred as stroma, and membrane sacs, known as thylakoids, which are organized in stacks and localized in the stroma.
Chloroplasts carry out photosynthesis: transformation of the electromagnetic energy of the light into chemical bonds of organic molecules.
Photosynthesis is accomplished in two stages: a light-dependent part where light energy is used to synthesize ATP and NADPH, which happens in the thylakoidal membranes, and a light-independent part where carbon from CO2 is covalently linked to ribulose-1,5-bisphosphate, which happens in the stroma.
Chloroplasts are usually large organelles (1 to 10 µm) present in plant cells. A cell from a leaf may contain from 20 to 100 chloroplasts. The shape of chloroplasts is variable, from round to ellipsoid, or much more complex. Chloroplasts are members of the plastids family and contain DNA, around 250 genes derived from the prokaryotic ancestor (see endosymbiosis). These genes code for ribosomal RNA, transference RNA and messenger RNA. In the interior of the chloroplast, proteins needed for the growth and division, and for photosynthesis, are synthetized.
Chloroplasts of a photosynthetic parenchyma (A), and in cells of a stoma (B).
Chloroplasts are composed of outer membrane, inner membrane, intermembrane space between them, the inner space is known as stroma and contains many membrane sacs known as thylakoids, arranged in stacks.
Chloroplasts are made up of several compartments. In the periphery, there are an outer membrane, an inner membrane and an intermembrane space

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Retrieved Text: Imagine that after eating a big salad, you were able to use the photosynthetic pigments in the lettuce to your advantage. Such is the case with Elysia chlorotica, and a few other unusual species of sea slugs. These unique animals are able to incorporate the photosynthetic components from the algae they eat into their own bodieseffectively becoming partially solar-powered.
Elysia chlorotica is a species of sea slug that is found along the eastern coast of North America, from Nova Scotia to Florida. The sea slugs live in coastal salt marshes, tidal marshes, tidal pools, and shallow creeks. As a juvenile, E. chlorotica is reddish-brown in color. After feeding on the alga Vaucheria litorea, the sea slug turns a brilliant shade of green. Why does this dramatic change happen? As the sea slug digests the algae, it is able to retain the algae’s chloroplasts, or photosynthetic structures. These chloroplasts are sent to the surface of the sea slug’s body–where, curiously, they continue to photosynthesize.
Dr. Mary Rumpho, a professor of biochemistry at the University of Maine, studies E. chlorotica. Her research interests include learning how the sea slugs are able to photosynthesize by studying the relationship between the sea slugs and their algal food source. A second research project is focused on determining whether the large amount of mucous the soft-bodied sea slug produces as an anti-predator defense mechanism has any potential as an anti-cancer or anti-microbial medium.
Rumpho and her colleagues collected sea slugs from an intertidal marsh on Martha’s Vineyard (a large island located off the coast of

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Retrieved Text: Mitochondria were isolated from lymphoblasts derived from normal (squares) or TRMA individuals (circles) were incubated for 15 minutes with various concentrations of radioactive thiamine.
Mitochondria were isolated from normal (open squares) or TRMA (open circles) lymphoblasts and were incubated for 15 minutes with various concentrations of radioactive ThDP.
Uptake of thiamine and ThDP by mitochondria was determined by a rapid filtration procedure [26,28].
Mitochondria are membrane-enclosed organelles distributed through the cytosol of most eukaryotic cells.
This has strengthened the theory that mitochondria are the evolutionary descendants of a bacterium that established an endosymbiotic relationship with the ancestors of eukaryotic cells early in the history of life on earth.
Perhaps rickettsias are the closest living descendants of the endosymbionts that became the mitochondria of eukaryotes.
Mitochondria are responsible for converting nutrients into the energy-yielding molecule adenosine triphosphate (ATP) to fuel the cell's activities.
This function, known as aerobic respiration, is the reason mitochondria are frequently referred to as the powerhouse of the cell.
Mitochondria are unusual organelles in that they contain deoxyribonucleic acid (DNA), typically found in the cell’s nucleus, and ribosomes, protein-producing organelles abundant in the cytoplasm.
Mitochondria are able to modify their structure to meet the changing requirements of the cell.
Mitochondria may fuse or increase in size to form giant mitochondria or megamitochondria, and they are also able to divide in a sequence that morphologically resembles bacterial division.
Mitochondria tend to locate near the structures were the energy is required, as illustrated by the close association with rough endoplasmic reticulum in cells with high synthetic activity.
Mitochondria are sometimes described as "cellular power plants", because their

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Retrieved Text: Learn vocabulary games, terms, , more mitochondria with coloring flashcards, other study tools. Chloroplasts Mitochondria Plant cells some Algae contain an organelle called the chloroplast. Put a check in the appropriate column( s) to indicate whether the following organelles are found in plant cells animal cells both. Use the organelles listed in the word bank. Coloring the Animal Cell Directions: Choose a color for each of the parts below and fill in the square with the color coloring of your choice. Acidophilus milk - Milk to which Lactobacillus acidophilus bacteria sheet have been added to aid in the digestion of lactose ( milk sugar). A chemical formula is a way of expressing information about the proportions of mitochondria atoms that constitute a particular chemical compound using a single line of chemical element symbols numbers. Organelle Color Organelle mitochondria Color Cell Membrane Ribosome Cytoplasm Smooth ER Rough ER Golgi Apparatus ( Body) Mitochondria Nucleolus Lysosome. Link Dwonload Chloroplast mitochondria Mitochondria mitochondria Coloring Worksheet Answer Key Pdf, Where I can Download Chloroplast , Read File Chloroplast , MOBI file of Chloroplast , Mitochondria Coloring Worksheet Answer Key, Mitochondria Coloring Worksheet Answer Key pdf live, Mitochondria Coloring Worksheet Answer Key Free Download File Chloroplast.
The chloroplast allows plants to harvest. Full page fax print Author: Owner. Specialized pigments in the chloroplast ( including the common green. sheet Mitochondria Zooxanthellae Plant Animal Cells Summary Students will begin the unit by finding out what the mitochondria differences are between coloring plant animal cells. Stewart' s Biology Class. Color Coded Cells Read the

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Retrieved Text: Tired of Endless Searching? Find Endoplasmic Reticulum Structure on DealsNow.
Start studying Endoplasmic Reticulum. Learn vocabulary, terms, and more with flashcards, games, and other study tools.
Does the Smooth Endoplasmic Reticulum create steroids? One of the primary functions of the Smooth Endoplasmic Reticulum is to produce and move lipids, an essential component of a cell's outer membrane, and steroids.
The ribosomes are located on the cytosolic side of the endoplasmic reticulum, which is also called the ER. The presence of these ribosomes on the outer layer of the RER distinguishes it from smooth endoplasmic reticulum, which is known as the SER. In addition to producing proteins, the RER plays an essential role in many other functions.
Unformatted text preview: 1 Quizlet 2 Main function of Cytosol Are the nuclear envelope and ER double membraned? Chloroplasts Endoplasmic reticulum ER Endosomes Golgi apparatus Golgi, lysosomes, endosomes, and nuclear membrane proteins and lipids are from where? How do cytosolic proteins enter the mitochondria and chloroplasts?

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Retrieved Text: Plastids are found in plants and some algae. They are necessary for essential life processes, like photosynthesis and food storage. Read this lesson to learn about major types of plastids and what they do to sustain life.
Did you ever wonder how plants breathe, drink, eat, and grow? They carry out these functions just like us, yet in different ways. One category of specialized organelles that plants use in order to survive is plastids.
Plastids are double membrane-bound organelles found inside plants and some algae, which are primarily responsible for activities related to making and storing food. Many plastids are photosynthetic, but some are not.
The chloroplasts are probably the most-known of the plastids. These are responsible for photosynthesis. The chloroplast is filled with thylakoids, which is where photosynthesis occurs, and chlorophyll.
Chromoplasts are what the name describes, a place for the pigments to be stored and synthesized in the plant. These are found in flowering plants, fruits, and aging leaves. The chloroplasts actually convert over to chromoplasts. There are carotenoid pigments here that allow for the different colors you see in fruits and the fall leaves. One of the main reasons for these structures and the colors is to attract pollinators.
Gerontoplasts are basically chloroplasts that are going through the aging process. These are chloroplasts of the leaves that are beginning to convert into different organelles or are being re-purposed, since the leaf is no longer utilizing photosynthesis (such as in the fall months).
Leucoplasts are the non-pigmented organelles. Unlike the others we have talked about, leucoplasts have no color at

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Retrieved Text: Prepare to receive your Biology The Essentials 1st Test Bank in the next moment.
1. What does a pine tree, an octopus, and a bacterium have in common at the microscopic level?
A. Mathias Schleiden and Theodore Schwann.
3. Why are cells called “the fundamental unit of life”?
A. All known organisms have one or more cells.
B. Earliest life on Earth is hypothesized to have been single-celled.
C. Some cells are separate living entities that can survive individually.
D. Cells are the smallest unit of life that can function independently.
D. Mathias Schleiden and Theodore Schwann.
5. Which component of the cell theory argues against life on Earth evolving from inorganic molecules?
A. All organisms are made of one or more cells.
B. The cell is the fundamental unit of all life.
C. All cells come from preexisting cells.
D. Cells are small in size.
E. All cells are either prokaryotic or eukaryotic.
B. Mathias Schleiden and Theodore Schwann.
C. all organisms have DNA, all organisms are made of cells, and all cells produce proteins.
8. How do cells avoid surface area limitations?
E. a sugar molecule attached to a protein.
A. has a hydrophilic head that is repelled by water.
B. has hydrophilic tails that are repelled by water.
C. has a hydrophilic head that is attracted to water.
D. has a hydrophobic head that is repelled by water.
E. has hydrophobic tails that are attracted to water.
E. composed of phospholipid molecules.
D. hydrophilic and selectively permeable.
E. hydrophobic and selectively permeable.
A. has a cell wall with peptidoglycan.
B. is usually smaller than a prokaryotic cell.
C. does not have membrane-bound organelles.
A. Bacteria, Animalia, and Plantae.
B. Fungi, Protista, and Animalia.
C. Archaea,

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Retrieved Text: 1. Indicate whether the following statements are True (T) or False (F).
2. Make a sketch of the human nerve cell. What function do nerve cells perform?
The function of a nerve cell is to transmit messages to the brain and also to take away messages from the brain to the receptor organs.
(a) Cytoplasm: It is a fluid that fills the cell and occurs between the plasma membrane and the nucleus. Cell organelles such as mitochondria, ribosomes, Golgi bodies, etc. are suspended in the cytoplasm. The cytoplasm helps in the exchange of materials between cell organelles.
(b) Nucleus of a cell: Nucleus is the master of the cell. It commands all the functioning of the cell. It is generally located in the center of the cell and is spherical in shape. A membrane called nuclear membrane separates it from cytoplasm. It contains the genetic material DNA and RNA in it. This porous membrane allows the transfer of material in the nucleus and cytoplasm. Nucleus contains a dense body called Nucleolus which actually contains Chromosomes, the genetic material.
4. Which part of the cell contains organelles?
Cytoplasm is the part of the cell that contains various organelles such as mitochondria, ribosomes, Golgi bodies, etc.
5. Make sketches of animal and plant cells. State three differences between them.
They are generally small in size. They are usually larger than animal cells.
Cell wall is absent. Cell wall is present.
Vacuoles are small in size. Vacuoles are larger in size.
No other animal cell possesses plastids except for the protozoan Euglena. Plastids are present.
6. State the difference between eukaryotes

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Retrieved Text: 2) All cells carry out life activities (require energy, grow, have a limited size). Function - Organelles are found here and substances like salts may be dissolved in the cytoplasm. 3. There are two types of ER: rough ER and smooth ER. BIO Lab: Cell Organelles Computer Lab. All cells, whether they are prokaryotic or eukaryotic, have some common features. which may be used to pull two cells in close contact, and perhaps to facilitate the transfer of genetic material. Every cell in your body contains organelles (structures that have specific functions). The nucleus, mitochondria and chloroplasts are all organelles. Within cells, organelles tend to cluster close to where they do their job. For instance, the TEM showed that mitochondria contained two membranes and.
All cells, whether they are prokaryotic or eukaryotic, have some common features that consists of a fluid portion called the cytosol and the organelles and other. Like our cells, bacteria cells have DNA and a plasma membrane. But bacteria There are two basic types of cells, prokaryotic cells and eukaryotic cells. They do not have a nucleus or other membrane-bound organelles. Most organelles are common to both animal and plant cells. However, plant cells also have features that animal cells do not have: a cell wall, a large central vacuole, Between these two layers is the intermembrane space.
You can do all this because you are made of cells — tiny units of life that are like There are two main types of cells, prokaryotic and eukaryotic. All cells have membranes (the building), DNA

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Retrieved Text: Animal cells never have cell walls.
This Biology quiz is called 'Cell Structure' and it has been written by teachers to help you if you are studying the subject at middle school. Playing educational quizzes is a fabulous way to learn if you are in the 6th, 7th or 8th grade - aged 11 to 14.
Students of middle school Biology will be expected to familiarize themselves with the various features of plant and animal cells, such as the nucleus or the mitochondria for example. This quiz on cell structure will help them to do just that.
In the early 1800s, Scottish scientist Robert Brown was examining plant cells under a microscope when he noticed that there was a similar structure in each and every cell he looked at. It had been seen before but it was Brown who first realized it was present in all plant cells, and he called it ‘the nucleus’.
We now know that animal and plant cells have many features in common - a nucleus, cytoplasm, mitochondria, ribosomes and a cell membrane. Plant cells have chloroplasts for photosynthesis, a permanent vacuole and a cell wall. Brown had no idea of the importance of the nucleus, or that it was also found in animal cells too, but scientists have gradually discovered more and more about how cells work.
The nucleus contains the DNA of an organism and it is this that instructs the cell what to do and how to do it. Most cells contain DNA but bacterial cells do not have a nucleus as the DNA

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Retrieved Text: Are you looking for NCERT Class 8 Solution? Download NCERT Solution Class 8 Science Chapter 8 : Cell-Structure and Functions and prepare better for your examinations.
Question 1: Indicate whether the following statements are True (T) or False (F).
Question 2: Make a sketch of the human nerve cell. What function do nerve cells perform?
The function of a nerve cell is to transmit messages to the brain and also to take away messages from the brain to the receptor organs. Thus, it controls the working of different parts of the body.
Question 3: Write short notes on the following.
It is a fluid that fills the cell and occurs between the plasma membrane and the nucleus. Cell organelles such as mitochondria, ribosomes, Golgi bodies, etc. are suspended in the cytoplasm. The cytoplasm helps in the exchange of materials between cell organelles.
It is a double-layered membrane which separates the contents of the nucleus from the cytoplasm. The nuclear membrane has nuclear pores that allow the transfer of specific substances in and out of the nucleus.
It is a small spherical body that is not bound by any membrane.
These are thread-like structures that carry genes. Genes contain information necessary for the transfer of characteristics from the parents to the offspring. Thus, chromosomes play an important role in the inheritance of characteristics.
Question 4: Which part of the cell contains organelles?
Cytoplasm is the part of the cell that contains various organelles such as mitochondria, ribosomes, Golgi bodies, etc. Cytoplasm is a fluid that fills the cell and occurs between the plasma membrane and the nucleus.
Question

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Retrieved Text: What goes on in a mitochondrium at the analog to A? Source # 2: chloroplasts and mitochondria coloring worksheet answer key. What are the analogs of each of those labeled parts in a mitochondrium? Coroplast ® Overview & Product Details Coroplast' s main product is corrugated plastic sheet. Photosynthesis Diagrams Worksheet Part I: In the diagram below, label parts A- L next to the words in the structures of. The main function of the chloroplast is photosynthesis. Showing top 8 worksheets in the category - Chloroplast And Mitochondria. Chloroplast sheet. Remember to click the add selected questions to a test button before moving to another page. Coroplast is a high- quality polypropylene twinwall profile sheet formulated for use in the screen printing display, packaging markets. Title: Microsoft Word. Rated 5 out of 5 by customwebprogrammer from Easy to cut and glue: I made a frame for casting a resin table. contain an organelle called the. New clients are expected to pay for the courier cost the samples are free for you this charge will be deducted from the payment for formal order. Other plastid types such as the leucoplast , the chromoplast, contain little chlorophyll do not carry out photosynthesis.
by Falken Design Corporation. 05 $ 33 05 Prime. Search Results for chloroplast - All Grades. Chloroplasts Mitochondria Plant cells some Algae contain an organelle called the chloroplast. 388 questions match " chloroplast". Refine Your Search Select questions to add to a test using the checkbox above each question. Corrugated Fluted Plastic Sheet 4mm ( 0. A

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Retrieved Text: Organisms are composed of cells, and these cells have specific structures within in them that allow them to carry out their functions. These structures are called Organelles. The fine detail of the cell (which may be revealed by an electron microscope) is called the cell's ultrastructure. Organelles perform different functions within a cell, and this is called the Division of Labour.
The Nucleus is the largest organelle in a cell. It contains a dense structure called the Nucleolus and is surrounded by the Nuclear Envelope, a structure composed of two membranes, seperated by fluid, which contain a number of nuclear pores that can allow relatively large molecules through. The nucleus contains nearly all of the cell's genetic material. The Nucleolus creates Ribonucleic Acid and Ribosomes, which then travel out of the nucleus, through the nuclear pores, to the cytoplasm where they are involced in Protein Synthesis.
The Endoplasmic Reticulum (ER) is found near the Nucleas and is made up of a number of flattened sacs called Cisternae, which are continuous with the Nuclear Envelope. The Rough Endoplasmic Reticulum is called so because it has a lot of Ribosomes on its outer surface. The Smooth Endoplasmic Reticulum however, does not have Ribosomes. The Rough transports proteins that are synthesised in the Ribosomes, and the Smooth synthesises Lipids.
The Golgi Apparatus is a stack of membrane bound flattened sacs, and are responsible for the modification of proteins received from the ER. These proteins are then transported in vesicles around the cell.
Lysosomes are membrane bound spherical sacs which contain digestive enzymes used

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Retrieved Text: Aging is a complex process involving lots of different mechanisms. One of the main processes on which aging is based is the formation of reactive oxygen species (ROS). ROSs are molecules formed as a result of a sequential one-electron reduction of oxygen. They are extremely chemically active and oxidize many compounds inside the cells. This leads to malfunctions in cellular molecular mechanisms and eventually to cell death.
ROSs are frequently formed in mitochondria—the power factories of the cells. Mitochondria-targeted antioxidants, including SkQ ions, affect mitochondria directly and prevent the synthesis of dangerous molecules. Their action mechanism is not completely clear yet, but scientists believe it consists of two parts. The first one is a chemical reaction of SkQ with ROS or their products. The second is implemented due to the reduction of transmembrane difference of electric potentials in mitochondria which suppresses the formation of mitochondrial ROS.
A team from the department of immunology (Faculty of Biology, MSU) tested the effect of SkQ mitochondria-targeted antioxidants on plant cells. The main target of the study was to determine the influence of these substances on chloroplasts in which photosynthesis takes place. The scientists demonstrated that in nanomolar concentrations, SkQ suppressed the death of plant cells caused by the influence of poisons in pea leaves. In micromolar concentrations, the antioxidants slowed down photosynthesis in chloroplasts and stimulated respiration in mitochondria. The team also found out that SkQ antioxidants slowed down the senescence and death in the leaves of Arabidopsis thaliana, a plant from the Cruciferae family.
"An important moment for us was finding

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Retrieved Text: Plants have many valuable functions: They provide food and fuel, release the oxygen that we breathe, and add beauty to our surroundings. Now, a team of MIT researchers wants to make plants even more useful by augmenting them with nanomaterials that could enhance their energy production and give them completely new functions, such as monitoring environmental pollutants.
In a new Nature Materials paper, the researchers report boosting plants’ ability to capture light energy by 30 percent by embedding carbon nanotubes in the chloroplast, the plant organelle where photosynthesis takes place. Using another type of carbon nanotube, they also modified plants to detect the gas nitric oxide.
Strano and the paper’s lead author, postdoc and plant biologist Juan Pablo Giraldo, envision turning plants into self-powered, photonic devices such as detectors for explosives or chemical weapons. The researchers are also working on incorporating electronic devices into plants. “The potential is really endless,” Strano says.
The idea for nanobionic plants grew out of a project in Strano’s lab to build self-repairing solar cells modeled on plant cells. As a next step, the researchers wanted to try enhancing the photosynthetic function of chloroplasts isolated from plants, for possible use in solar cells.
Chloroplasts host all of the machinery needed for photosynthesis, which occurs in two stages. During the first stage, pigments such as chlorophyll absorb light, which excites electrons that flow through the thylakoid membranes of the chloroplast. The plant captures this electrical energy and uses it to power the second stage of photosynthesis — building sugars.
Chloroplasts can still perform these reactions when removed

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Retrieved Text: where the RNA molecules found in ribosomes are manufactured and the large and small ribosomes subunits are assembled.
proteins of R. ER, carry messages to other cells, act as a membrane transport proteins of pumps, or as enzymes.
rough ER products are packaged into vesicles and transported to various distant destinations.
parts of ER that are free of ribosomes.
reservoir for calcium ions that act as a signal triggering a wide array of activities inside cell.
products of the rough ER pass through the Golgi apparatus before they reach their final destination.
the enzymes catalase quickly "detoxifies" hydrogen peroxide by converting it to water and oxygen.
the plasma membrane of a cell surrounds a smaller cell or food particle and engulfs it, forming a structure called a phagosome.
molecules outside the cell bind to membrane protein that act as receptors.
when early endosome matures into late endosome , the structures receives digestive enzymes from the golgi apparatus and may eventually become fully functioning lysosome.
Why is the DNA in mitochondria considered vestigial or “remnant DNA”?
many of the pigments, enzymes, and molecular mechines responsible for converting light into energy into carbohydrates are embedded in the thylakoid membranes.
where critical enzymes and substrates are found outside the thylakoids.
fungi, algea, and plant have cell wall along with plasma membrane.
What makes the cell wall of a bacterium different from a plant? From a fungus?
plant cells produce a secondary cell wall that features a particularly tough molecule called lignin.
Where did the nuclear envelope come from? What advantage does this give eukaryotes over prokaryotes?
What components make up the endomembrane system? Why are lysosomes

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Retrieved Text: Imagine you swallowed a small bird and suddenly gained the ability to fly … or you ate a cobra and were able to spit poisonous venom! Well, throughout the history of life (and specifically during the evolution of complex eukaryotic cells) things like this happened all the time. Adam Jacobson explains endosymbiosis, a type of symbiosis in which one symbiotic organism lives inside another.
Endosymbiosis--the symbiotic relationship where one symbiotic organism living inside another! Where did this theory come from? Biologist Lynn Margulis proposed the idea of endosymbiosis about 50 years ago. She proposed it as the explanation for how complex cells evolved. Read why she was called a “biology rebel” in this Scientific American Blog post. Her idea was not readily accepted, but in 1966 she finally convinced the recently founded Journal of Theoretical Biology to publish one of her papers. In 1970, she published a book called Origin of Eukaryotic Cells. The discovery of better technology in the 1980s, greatly improved our ability to study DNA. As a result, more genetic evidence became readily available. Margulis’ theory gained support and is now the dominant explanation for the origin of chloroplasts and mitochondria inside eukaryotic cells. Detailed information can be found here.
A vast variety of assimilation events are thought to have occurred throughout the evolution of different branches of the tree of life. Especially in the groups of microorganisms known as protozoans, evidence exists for tertiary and quaternary endosymbiosis, i.e. an organism that had already absorbed one cell being absorbed itself by another cell. Microbiologists are

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Retrieved Text: Find Deals on Chloroplast Boards in Office Supplies on Amazon.
What is the importance of chloroplast to the cell?
Chloroplasts are important because if there were no chloroplasts, plants would not produce oxygen, sugars and starches which other animals use and eat.
An important feature of these chloroplasts is that their chloroplast DNA is highly reduced and fragmented into many small circles. Most of the genome has migrated to the nucleus, and only critical photosynthesis-related genes remain in the chloroplast.
Chloroplast. Chloroplasts are organelles — specialized parts of a cell that function in an organ-like fashion. They are found in vascular plants, mosses, liverworts, and algae. Chloroplast organelles are responsible for photosynthesis, the process by which sunlight is absorbed and converted into fixed chemical energy in the form of simple sugars synthesized from carbon dioxide and water.
it is important to achuchu.

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Retrieved Text: They are found in leaves and carry out photosynthesis and cellular respiration, along with other metabolic processes. With specialized organelles doing specific jobs, the accomplishments of a cell are really quite impressive. Label the axon, dendrites, cell body, nucleus, Schwann's cells, and nodes of Ranvier. It contains the genetic material i. The water rushes into the cell through osmosis. Cells communicate with one another and are responsible for transmitting information from one generation of cells to another.
It produces the membranes that surround the lysosomes. Vesicles; are much smaller than vacuoles and function in transport within and to the outside of the cell. This page has worksheets, articles, and activities to use when teaching students about the human body. More complex tracheids with valve-like perforations called characterise the gymnosperms. Ribosomes are the producers of our factory-like cell.
Individual cell parts can be colored, if desired, as part of the labeling process. The cytoskeleton is a network of filaments and tubules found throughout the cytoplasm of the cell. The composition of the plant cell wall differentiates it from the cell walls of other organisms. Chloroplasts of Green Algae Protista and Plants descendants of some Green Algae are thought to have originated by endosymbiosis of a prokaryotic alga similar to living Prochloron Prochlorobacteria. Like a suitcase is tagged for a destination, the vesicles are now marked for their future location within the cell before they are dispatched. Centrioles form the tail, which moves the sperm toward the ovum. The centrosomes is where microtubules are made.
Sugars produced by photosynthesis in chloroplasts

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Retrieved Text: Current Topics in Bioenergetics, Volume 16 focuses on photosynthetic electron transfer, ATP-synthesizing reactions, and nitrogen fixation. It looks at the application of biochemistry and biophysics in the exploitation of gene isolation, sequencing, and analysis of structure and function. It also reviews photosystems I and II and electron transfer reactions in eukaryotic chloroplasts of more modern plants as well as in photosynthetic membranes of the very ancient cyanobacteria. Organized into seven chapters, this volume begins with an overview of photosystems I and II. Then, it discusses the ATP synthesis in chloroplasts, with special attention given to the genes and their protein products that produce the ATP synthase complexes of the plant mitochondria and chloroplasts. The reader is then introduced to the mechanism of proton gradient formation and calcium-gated control of the type of gradient formed, the evidence for localized domains of proton accumulation, the reaction center of purple bacteria, and the physical aspects of electron transfer. The final chapter examines the nitrogen fixation in plants and bacteria, with emphasis on the metabolic origins of the reducing power and ATP used in nitrogen fixation. Biophysicists, biochemists, and others interested in bioenergetics will find this book highly informative.

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Retrieved Text: RNA editing is a type of post-transcriptional modification of RNA and belongs to the class of mechanisms that contribute to the complexity of transcriptomes. C-to-U RNA editing is commonly observed in plant mitochondria and chloroplasts. The in vivo mechanism of recognizing C-to-U RNA editing sites is still unknown. In recent years, many efforts have been made to computationally predict C-to-U RNA editing sites in the mitochondria of seed plants, but there is still no algorithm available for C-to-U RNA editing site prediction in the chloroplasts of seed plants.
In this paper, we extend our algorithm CURE, which can accurately predict the C-to-U RNA editing sites in mitochondria, to predict C-to-U RNA editing sites in the chloroplasts of seed plants. The algorithm achieves over 80% sensitivity and over 99% specificity. We implement the algorithm as an online service called CURE-Chloroplast http://bioinfo.au.tsinghua.edu.cn/pure.
CURE-Chloroplast is an online service for predicting the C-to-U RNA editing sites in the chloroplasts of seed plants. The online service allows the processing of entire chloroplast genome sequences. Since CURE-Chloroplast performs very well, it could be a helpful tool in the study of C-to-U RNA editing in the chloroplasts of seed plants.
RNA editing is a kind of RNA processing (like splicing, 5'capping and 3' polyadenylation) that can alter the genetic information of RNA via insertion, deletion or substitution of single or multiple nucleotides. In plant mitochondrial and chloroplast transcripts, several cytidines can be converted to uridines by a deamination process [1–3]. Generally, there are about 300 to 500 C-to-U RNA editing sites in the mitochondrial transcriptomes of

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Retrieved Text: Cutaway drawing of a eukaryotic cell. Encyclopædia Britannica, Inc.
Bacterial cells differ from animal cells and plant cells in several ways. One fundamental difference is that bacterial cells lack intracellular organelles, such as mitochondria, chloroplasts, and a nucleus, which are present in both animal cells and plant cells. Encyclopædia Britannica, Inc.
Eukaryotic cells contain membrane-bound organelles, including a clearly defined nucleus, mitochondria, chloroplasts (unique to plant cells), a Golgi apparatus, an endoplasmic reticulum, lysosomes, and peroxisomes. Encyclopædia Britannica, Inc.
The cell cycle is an ordered sequence of events that prepares a cell for the process of cell division. Encyclopædia Britannica, Inc.
meiosis; gameteGametes are formed through meiosis (reduction division). Encyclopædia Britannica, Inc.
…spindle, which is formed by centrioles (cylindrical cell structures). This climax in the events of fertilization creates a joint product known as the zygote, which contains all the factors essential for the development of a new individual.

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Retrieved Text: Dogs and cats, butterflies and crayfish, lizards and birds, poison ivy and rosebushes and strawberry plants are all organisms. Organisms are composed of organ systems (digestive, circulatory or immune systems, to mention three examples). These systems are in turn composed of organs, which are composed of tissues which are composed of cells. The cell is where the action is!
The definition of life usually includes the requirement that whatever lives is capable of viable reproduction, which makes it subject to evolution. All life is composed of cells and they reproduce.
Eukaryotic contain structures called organelles, many of which are not found in prokaryotic cells. One such organelle is the nucleus, which houses the DNA.
Prokaryotic cells are usually smaller. They do not contain nuclei, so their DNA is floating around in the cytoplasm. They do contain ribosomes to carry out protein synthesis.
Cells come in a huge variety of shapes and functions. They are the basis of all living beings. Whether they are nerve cells, muscle cells, skin cells, bone cells or any other kind of cells; whether they come from humans or cats or grasshoppers or oak trees or bacteria, they all are based on common features like a membrane filled with cytoplasm, DNA or RNA along with ribosomes for reproduction, and the fabrication by cellular respiration of ATP for energy. This fact seems to represent a certain indication of the common origin of all life.
As we saw in the discussion of water, lipid bilayers, in this case, phospholipid bilayers, can form membranes. All cells are surrounded and protected

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Retrieved Text: A chromosome is an organized structure of DNA and protein that is found in cells. It is a single piece of coiled DNA containing many genes, regulatory elements and other nucleotide sequences. Chromosomes also contain DNA-bound proteins, which serve to package the DNA and control its functions. The word chromosome comes from the Greek χρῶμα (chroma, color) and σῶμα (soma, body) due to their property of being very strongly stained by particular dyes. Chromosomes vary widely between different organisms. The DNA molecule may be circular or linear, and can be composed of 10,000 to 1,000,000,000 nucleotides in a long chain. Typically eukaryotic cells (cells with nuclei) have large linear chromosomes and prokaryotic cells (cells without defined nuclei) have smaller circular chromosomes, although there are many exceptions to this rule. Furthermore, cells may contain more than one type of chromosome; for example, mitochondria in most eukaryotes and chloroplasts in plants have their own small chromosomes.
In eukaryotes, nuclear chromosomes are packaged by proteins into a condensed structure called chromatin. This allows the very long DNA molecules to fit into the cell nucleus. The structure of chromosomes and chromatin varies through the cell cycle. Chromosomes are the essential unit for cellular division and must be replicated, divided, and passed successfully to their daughter cells so as to ensure the genetic diversity and survival of their progeny. Chromosomes may exist as either duplicated or unduplicated—unduplicated chromosomes are single linear strands, whereas duplicated chromosomes (copied during synthesis phase) contain two copies joined by a centromere. Compaction of the duplicated chromosomes during

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======= Instance Index 7475 =========
Input Text: Answer the following question given this paragraph: 

The veins that return oxygen-poor blood to the heart are the superior vena cava and the inferior vena cava . The pulmonary veins return oxygen-rich blood from the lungs to the heart. The pulmonary veins are the only veins that carry oxygen-rich blood.


Q: The superior vena cava and the inferior vena cava are veins that return blood lacking what to the heart?

 Choices:

- carbon dioxide

- hemoglobin

- oxygen

- nitrogen

A:

Target Text: oxygen

#### Retrieved Documents ####

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Score: 115.84301
Retrieved Text: Inferior vena cava is one of the two major vein (the other being superior vena) of the systemic circulation, which bring blood from the body back to the heart. It conveys most of the blood from the body below the diaphragm.
The inferior vena cava is formed by the union of the common iliac veins behind the right common iliac artery. This union occurs at about the level of fifth lumbar vertebra.
After its origin, the inferior vena cava ascends to the right side of the aorta and pierces the central tendon of the diaphragm at the level of eighth thoracic vertebra. Finally, the vena cava drains into the right atrium.
Right sympathetic trunk: It lies behind the right margin of the inferior vena cava.
Right ureter: It lies at a distance of about half inch from the right border of inferior vena cava.
Entrance into lesser sac of peritoneal cavity: It separates the inferior vena cava from the portal vein.
Anterior visceral tributaries: These include the two hepatic veins.
Lateral visceral tributaries: These include the right suprarenal vein, renal veins and right testicular or ovarian vein.
Abdominal wall tributaries: These include the inferior phrenic vein and four lumbar veins.
Veins of origin: These are the veins which unite to form the inferior vena cave. These are: Median sacral vein and left and right common iliac veins.
Remembering the tributaries of inferior vena cava seems difficult, however, if one keeps in mind that abdominal portion of the gastrointestinal tract is drained by portal vein, and that the left suprarenal and testicular (or ovarian) veins first drain

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Retrieved Text: Cava is a Spanish wine originating from Catalonia. Vena cava is either of two larges vein carrying deoxygenated blood, not Spanish wine, back into the heart. Unless you’re blood-alcohol level is unseasonable high as a result of too much cava.
The superior vena cava carries blood from the upper part of the body back to the heart, whereas superior cava include Gramona 2002 Enoteca Gran Reserva Brut Nature and Agustí Torelló Mata 2007 Kripta Gran Reserva Brut Nature 40 Anys, both of which received 93 points from Wine Enthusiast.
Th inferior vena cava carries blood from the lower part of the body back to the heart, whereas inferior cava should be avoided since you can find some excellent bottles of superior cava, such as Barcino Belle Epoch Brut or Vilarnau Brut Reserva Cavas, for less than $20 a bottle.
Though Catalonia is known for producing cava, it is not known for producing vena cava. This is a very common misconception. Human beings are born with venae cavae. Catalonians, on the other hand, cannot live without cava. Cava courses through their arteries and veins, which includes their venae cavae.
Traditionally, venae cavae are blue while cava is white or rosé.

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Retrieved Text: Veins are vessels designed to collect and return blood, including deoxygenated hemoglobin, from tissues to the heart. In humans, veins and the venous vascular system can be divided in to three separate systems depending on anatomical relationships and function. Initially, veins can be divided into systemic and pulmonary systems. The veins that drain the heart, comprising the coronary venous system, may be described as an independent venous system, or be considered a subset of the systemic vascular system. The systemic veins transport venous blood—deoxygenated when compared with arterial blood—from the body to the heart. The pulmonary veins return freshly oxygenated blood from the lungs to the heart so that it may be pumped into the systemic arterial system.
Veins can also be described by their anatomical position. Deep veins run in organs or connective tissue that supports organs, muscle, or bone. Superficial veins are those that drain the outer skin and fascia.
In contrast to arteries, veins often run a more convoluted course, with frequent branching and fusions with other veins (anastomoses) that make the tracing of the venous system less straightforward than mapping the arterial system. In addition, there are reservoirs or pools (sinus) that collect venous return from multiple sources. Many veins contain valves that assure a unidirectional (one way) flow of venous blood toward the heart.
The systemic venous system can be roughly divided into groups depending on the region they drain, and the vessel through which they return blood to the heart.
The first systemic venous group consists of veins that drain the head, neck, thorax,

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Rank: 3
Score: 104.970406
Retrieved Text: Venous smart canula ® production is ISO 9001 certified and all available types of smart canula ® are CE 0344 labeled.
Venous smart canula ® for either peripheral or central venous cannulation with maximal cannula expansion from 18 F up to 45 F (maximal flow > 6l/min for a 28F access aperture) are available.
The 63 cm and 53 cm long venous smart canula ® is designed for peripheral (femoral) cannulation of the superior vena cava and the right atrium. They stretched with the corresponding mandrel and inserted over a guide wire. Care has to be taken that the guide wire is positioned in the superior vena cava (check position with TEE). Full flow can usually be achieved with gravity drainage alone and augmentation with a centrifugal pump or vacuum assist is not necessary. Main applications include small access open heart surgery, redo procedures, heart transplant after VAD implantation, etc.
The 43 cm medium venous smart canula ® is designed for peripheral (femoral) cannulation of the inferior vena cava. It is stretched with the corresponding mandrel and inserted over a guide wire. Care has to be taken that the guide wire is positioned in the superior vena cava (check position with TEE). Bi-caval cannulation for full CPB, or partial CPB are the most frequent applications. The 43 cm medium venous smart canula ® allows for open heart surgery without snare around the inferior vena cava and therefore the supra-hepatic veins can be inspected. Typical applications include intra-cardiac repair of congenital heart disease in grown-ups (GUCH), tricusoid valve repair and

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Rank: 4
Score: 100.2595
Retrieved Text: We just learned that the inferior vena cava vein brings deoxygenated blood back from the lower part of the body to the heart.
There is another large vein called the superior vena cava that brings deoxygenated blood down from the head area toward the heart.
When you're talking about the human body, superior means above, and inferior means below.

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Rank: 5
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Retrieved Text: The coronary sinus is a collection of veins joined together to form a large vessel that collects blood from the heart muscle (myocardium). It delivers deoxygenated blood to the right atrium, as do the superior and inferior vena cavae. It is present in all mammals, including humans.
The name comes from the Latin "corona' , meaning crown, since this vessel forms a partial circle around the heart. The coronary sinus drains into the right atrium, at the coronary sinus orifice, or "coronary os" between the inferior vena cava and the right atrioventricular orifice or tricuspid valve. It returns blood from the heart muscle, and is protected by a semicircular fold of the lining membrane of the auricle, the valve of coronary sinus (or valve of Thebesius). The sinus, before entering the atrium, is considerably dilated - nearly to the size of the end of the little finger. Its wall is partly muscular, and at its junction with the great cardiac vein is somewhat constricted and furnished with a valve, known as the valve of Vieussens consisting of two unequal segments.
The coronary sinus runs transversely in the left atrioventricular groove on the posterior side of the heart. It is the distal portion of the Great Cardiac Vein feeding into the Right Atrium.
The coronary sinus orifice (opening, also known as the ostium of the coronary sinus) is on the posterior, inferior surface of the heart, medial to the inferior vena cava opening, just superior to the septal leaflet of the tricuspid valve. The coronary sinus orifice is guarded by

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Rank: 6
Score: 96.6303
Retrieved Text: Venous smart canula mini ® production is ISO 9001 certified and all available types of smart canula mini ® are CE 0344 labeled.
Venous smart canula mini ® for either peripheral or central venous cannulation with maximal cannula expansion from 12 F up to 24 F are available. Maximal flow is 5 l/min for the 3/8 inch and 24 F smart canula mini ® and a 20F access aperture as compared to 4 l/min for the ¼ inch and 20 F design.
The 53 cm long 24F venous smart canula mini ® is designed for peripheral (femoral) cannulation of the superior vena cava and the right atrium in smaller patients (e.g. 40 kg). It has to be stretched with the corresponding mandrel and inserted over a guide wire. Care has to be taken that the guide wire is positioned in the superior vena cava (check position with TEE). Full flow can usually be achieved with gravity drainage alone and augmentation with a centrifugal pump or vacuum assist is not necessary. Main applications include small access open heart surgery, redo procedures, heart transplant after VAD implantation, etc.
The 43 cm medium venous smart canula mini ® is designed for peripheral (femoral) cannulation of the inferior vena cava or the right atrium. It is stretched with the corresponding mandrel and inserted over a guide wire. Care has to be taken that the guide wire is positioned in the superior vena cava (check position with TEE). As a function of body size, right atrial or bi-caval cannulation for full CPB, as well

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Rank: 7
Score: 96.43331
Retrieved Text: The function of systemic circulation is to carry oxygenated blood (provide oxygen and nourishment) to all parts of the body (except heart and lungs-which have their own systems) and deoxygenated blood from all the body parts back to the heart.
The Systemic circulation is the type of circulation, which carries the oxygenated blood from the heart to the body, and also brings back the deoxygenated blood from the body of the heart.
Its function is to carry oxygenated blood to the body and brings deoxygenated blood from the body to the heart.
In this circulation the blood leaves the left ventricles and enters the aorta. From here the blood is sent to the smaller arteries and the arterioles, and then finally to the capillaries. The oxygen is then comes in the blood in replacement of the waste and carbon dioxide. The blood to the veins then caries the waste away or we can say to the venous capillaries, and then the inferior vena cava and the superior vena cava, thus entering of the blood to the heart at the right atrium. The location of the Systemic Circulation is left side of the Heart.

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Rank: 8
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Retrieved Text: There have been many instances medical technologies have gone wrong! One of the famous names is the IVC filter technology. Simply put, an IVC is known as the “Inferior Vena Cava” that is the central vein which runs from your lower body right to your heart. It carries deoxygenated blood. And it’s the vena cava veins that transfers this deoxygenated blood directly to the right atrium of the human heart, where the blood gets oxygenated and gets sent back to our body. It is true that the IVC is a vitally essential vein that is within the body. Also, when there are issues, this vein can be life-threatening.
Ailments like pulmonary embolism and deep vein thrombosis are critical and life-threatening conditions. Hence, it’s not a wonder that medical technology had come up with a device that can avert death in such extreme medical conditions.
Simply put, an IVC Filter is a tiny metal cone-shaped device that is located at the inferior Vena Cava! Doctors insert it surgically using a vein right inside the neck. This filter enables the blood to flow freely. The filter was designed with the intention of capturing a blood clot that can move through an inferior vena cava. Right, when the IVC filter gets hold of these blood clots, averts the blood clot from passing via the lungs and it can prevent the chances of pulmonary embolism. When it was launched in the market, the filters became very popular. Estimates say that close to 250,000 people get IVC filter implanted in their bodies almost

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Rank: 9
Score: 95.55624
Retrieved Text: What is venous insufficiency and how can it be treated?
What are the most common causes of venous disorders?
If You Get Varicose Veins While Pregnant, Are They Permanent?
An estimated one in every five adults has varicose veins, and pregnancy often predisposes to developing them. One reason for their frequent occurrence in the legs of pregnant women is because of the pressure exerted on the lower extremities from normal pregnancy-related weight gain. Meanwhile, the US Office on Women’s Health notes that increased venous blood-pumping activity and volume occurs during pregnancy to support fetal growth, and also pressure exerted by the expanding uterus on a large vein (inferior vena cava) likewise increases pressure on vein walls.
Once a lower extremity varicosity develops, it rarely goes away on its own. At Palm Vein Center, we are experienced in treating varicose veins for both medical and cosmetic reasons.
In contrast to the major vein termed the superior vena cava(that carries blood from the head and upper extremities to the heart), the inferior vena cava (IVC) carries de-oxygenated blood from the lower portion of the body to the right atrium of the heart. Compression of the IVC can constrict venous blood flow during pregnancy, and a supine sleeping position during middle or late pregnancy has been well-linked to the pregnancy-linked complication of supine hypotensive syndrome.
While the three most common negative effects of varicose veins in the lower extremities are an unsightly appearance, pain, and itchiness, a blood clot is a far more serious consequence. An increased risk for a blood clot exists in pregnant

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Rank: 10
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Retrieved Text: What is an inferior vena cava filter placement?
An inferior vena cava (IVC) filter is a small device that can stop blood clots from going up into the lungs. The inferior vena cava is a large vein in the middle of your body. The device is put in during a short surgery.
Veins are the blood vessels that bring oxygen-poor blood and waste products back to the heart. Arteries are the blood vessels that bring oxygen-rich blood and nutrients to the body. A deep vein thrombosis (DVT) is a blood clot that forms in a vein deep inside the body. A clot occurs when blood thickens and clumps together. In most cases, this clot forms inside one of the deep veins of the thigh or lower leg.
The veins in your legs have tiny valves that help keep blood moving back up toward the heart. But a DVT may damage one or more of these valves. This causes them to weaken or become leaky. When this happens, blood starts to pool in your legs. This can also happen if you are immobile for a long period of time. Normally, muscles in the leg help blood move up in the veins when the muscles contract. When blood flows very slowly through the veins, this increases the risk that cells in the blood will stick together and form a clot.
DVT is a serious medical condition that can cause swelling, pain, and tenderness in your leg. In some cases, a deep clot in a leg vein can break free and stick in

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Rank: 11
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Retrieved Text: Intravenous leiomyomatosis (IVL) extending to inferior vena cava and heart is one of the most challenging conditions for surgical treatment. We explored the use of computerized tomography angiography (CTA) in preoperative assessment for this disease.
A cohort of 31 patients with IVL extending to inferior vena cava and heart were reviewed from the year 2002 to 2014, focusing on the preoperative CTA imaging characteristics and the surgical procedures in clinical treatment.
All patients were diagnosed correctly combining the clinical medical history and CTA imaging. Thirteen patients had tumors confined within the inferior vena cava, and 18 patients had tumors intruding into the right heart. Furthermore, 15 tumors were located in the right atrium alone, and 3 tumors involved both the right atrium and the right ventricle. All patients had simple or multiple soft tissue masses from the pelvis, with 22 tumors extending into inferior vena cava through the iliac veins and 9 tumors through the ovarian veins. Three patients had tumors invading into lung and underwent tumor thrombus resection in the pulmonary artery. Patients received either one-stage surgery or two-stage surgery dependent on patient general condition and tumor status. All operations were successfully performed by multidisciplinary cooperation, including gynecology, cardiac surgery, and vascular surgery, without severe surgical-related complications or deaths.
CTA imaging can present location, size, and full-scale extension pathway of IVL lesions, and can be used as first-line imaging technique in preoperative assessment, having great significance in making surgical plan and obtaining successful outcome.
Intravenous leiomyomatosis (IVL) is an extremely rare form of leiomyoma . IVL, originating from either

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Rank: 12
Score: 94.271706
Retrieved Text: Superior vena cava syndrome occurs when there is a partial blockage of the superior vena cava. The superior vena cava is the vein that moves blood from the upper half of the body to the heart. Some symptoms include shortness of breath, coughing, and swelling in the upper body.
Data from patients with superior vena cava syndrome, who reported starting treatments within the last 5 years.
Who has superior vena cava syndrome on PatientsLikeMe?

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Score: 94.17025
Retrieved Text: Persistent Left Superior Vena Cava (PLSVC) is rare but important congenital vascular anomaly. It results when the left superior cardinal vein caudal to the innominate vein fails to regress. It is most commonly observed in isolation but can be associated with other cardiovascular abnormalities. The presence of PLSVC can render access to the right side of heart challenging via the left subclavian approach, which is a common site of access utilized. Incidental notation of a dilated coronary sinus on echocardiography should raise the suspicion of PLSVC. Here we present a case of PLSVC that was discovered in an infant accidently after central line insertion.
Povoski SP. Long-term venous access. In: Pazdur R, Wagman LD, Camphausen KA, Hoskins WJ, eds. Cancer Management: A Multidisciplinary Approach Medical Surgical and Radiation Oncology. 11th ed. Lawrence, Kansas: CMP Medica (United Business Media); 2008: 969-980.
Biffi M, Boriani G, Frabetti L, Bronzetti G, Branzi A. Left superior vena cava persistence in patients undergoing pacemaker or cardioverter-defibrillator implantation: a 10-year experience. Chest. 2001;120:139-44.
Perloff JK. Congenital anomalies of vena caval connection. In: Perloff JK, eds. The Clinical Recognition of Congenital Heart Disease. 4th ed. Philadelphia: WB Saunders Company; 1994: 703-714.
Buirski G, Jordan SC, Joffe HS, Wilde P. Superior vena caval abnormalities: Their occurrence rate, associated cardiac abnormalities and angiographic classification in a paediatric population with congenital heart disease. Clin Radiol. 1986;37:131-8.
J. Marshall. On the development of the great anterior veins in man and mammalia: including an account of certain remnants of fetal structure found in the adult, a comparative view of these great veins in

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Retrieved Text: Superior Vena Cava Syndrome (SVCS) occurs when a person’s superior vena cava is partially blocked or compressed. The superior vena cava is a major vein in a person’s body. It carries blood from the head, neck, upper chest, and arms to the heart. Cancer is usually the main cause of SVCS.
More than 90% of cases of superior vena cava obstruction (SVCO) are caused by cancer – most commonly bronchogenic carcinoma, typically a tumour outside the vessel compressing the vessel wall – but it can, sometimes, have a benign cause.
SVCS is rare in children. However, SVCS in children can be life threatening. If your child has signs of SVCS, it is important to contact your child’s health care team immediately.
A child’s trachea is smaller and softer than an adult’s trachea. This means that it can swell or become constricted quickly, causing breathing problems.
SVCS is a group of symptoms that usually develop slowly. Because SVCS can cause serious breathing problems, it is an emergency. If you experience any of the symptoms listed below, contact your doctor immediately. Although SVCS is serious and causes symptoms that may be frightening, treatment works well for most people.
SVCS may develop quickly, completely blocking the airway. When this occurs, a person may need a ventilator to help with breathing until the blockage is treated. More commonly, if the blockage develops slowly, other veins may enlarge to carry extra blood. In these situations, the symptoms may be milder.
SVCS is more common for people who have lung cancer, Non-Hodgkin Lymphoma, or cancers that spread to

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Score: 92.44597
Retrieved Text: The space between the spinal dura and the periosteum lining the vertebral canal is called epidural space. It includes (a) tiny spinal arteries and (b) a network of veins-the internal vertebral venous plexus and Its filled up with loose areolar tissue and semiliquid fat.
All these are segmental arteries, which originate from ascending cervical and deep cervical arteries in the cervical region, from posterior intercostal arteries in the thoracic region, from lumbar arteries in the lumbar region and lateral sacral arteries in the sacral region. They go into the vertebral canal via intervertebral foramina along the spinal nerve roots. They supply spinal cord, its nerve roots and meninges and the surrounding bones and ligaments.
The internal vertebral venous plexus is a network of veins in the epidural space of the vertebral canal and goes through the length of the vertebral canal. These veins correspond to the dural venous sinus inside the cranial cavity and are constant with them via the foramen magnum.
The plexus is emptied by 4 subordinate longitudinal stations: 2 posterior and 2 anterior.
The anterior part of plexus gets large basivertebral veins (primary tributaries) emptying the aggressive reddish narrow inside the bodies of the vertebrae and sends efferent intervertebral veins via intervertebral foramina to drain into external vertebral plexus, which in turn drains into segmental veins.
The segmental veins are body wall veins, viz. vertebral, posterior intercostal, lumbar and lateral sacral veins.
Besides draining venous blood from the vertebrae, the internal vertebral venous plexus gets veins from spinal meninges and spinal cord.
The external vertebral venous plexus is located outside

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Rank: 16
Score: 91.10341
Retrieved Text: In which of the following chambers of the heart the Superior vena cava enters?
In which of the following chambers of the heart the Inferior vena cava enters?
In which of the following chambers of the heart the coronary sinus enters?
In which of the following chambers of the heart the pulmonary vein enters?
What are the Signs and Symptoms of Poor Nutrition?
Can we avoid getting a heart attack?

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Rank: 17
Score: 91.03579
Retrieved Text: Makes proteins and blood-clotting factors that your body needs.
Biliary tree. A network of tubes that carry bile out of the liver and into the gallbladder and the duodenum.
Bile ducts. Tubes between the liver and small intestine. Bile drains into them from the liver.
Duodenum. The first part of the small intestine. When bile leaves the liver, it flows through the bile ducts into the duodenum. Here, bile starts mixing with food to help digest fat.
Gallbladder. The organ that stores bile.
Spleen. An organ that filters blood. It also helps keep your body healthy and free of infection, as part of the immune system.
Splenic vein. A blood vessel that carries blood from the spleen to the portal vein.
Hepatic portal vein. A blood vessel that carries blood containing nutrients and oxygen from the digestive tract and spleen into the liver.
Inferior vena cava. A large vein that carries blood from the liver, intestines, legs, and kidneys to the heart.
Hepatic veins. Blood vessels that carry blood out of the liver to the inferior vena cava.
Hepatic artery. A blood vessel that carries blood with a fresh supply of oxygen into the liver from the heart.
All the blood that flows from the intestines, stomach, and spleen is filtered through the liver. The blood flows into the liver through the hepatic portal vein. It filters through the liver in a system of smaller and smaller veins. As blood passes over liver cells, these cells process nutrients in the blood. This processing makes products like proteins and sugars that your body can use. Blood is carried

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Retrieved Text: There are an increased number of patients in the United States and Europe who are receiving temporary inferior vena cava filters prior to elective surgery. The question is 1) what happens to these filters once they are placed and 2) are temporary vena cava filters really temporary?
The complication rate of vena cava filter insertion has been shown to be significant and 12 out of 1000 patients have died from the procedure. The common complications include perforation of the vena cava and migration of the filter as well as total occlusion of the vena cava despite anticoagulation. Patients have also developed pulmonary embolism, renal insufficiency, renal failure and new DVT formation after vena cava filter placement. Migration of caval filters into renal veins have also occurred. The large number of deep vein thrombosis and pulmonary embolism episodes in The United States (one million cases of venous thrombo-embolism and 350,000 cases of pulmonary embolism) explains a need for placement of a large number of vena cava filters.
Vena cava filters are placed temporarily before bariatric surgery, also known as morbid obesity surgery. Recent studies have shown that there is poor retrieval of these so called temporary filters. It is estimated that less than 2% of temporary filters are removed in The United States. Retrieval or removal rates in Europe have shown to be approximately 1 in 4 at 1 year follow-up. .
A recent editorial and a journal Phlebology by Dr. Lane and colleagues recommend that it is incumbent upon those that have placed temporary filters to remove them for

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Rank: 19
Score: 90.60994
Retrieved Text: Retroperitoneal space-occupying lesion with displacement of the inferior vena cava.
Home » Citations » Retroperitoneal space-occupying lesion with displacement of the inferior vena cava.
Summary of "Retroperitoneal space-occupying lesion with displacement of the inferior vena cava."
The differential diagnosis and therapy of retroperitoneal masses suspicious for soft tissue tumors remains difficult and needs individual decisions as to the best management of patients. We report an unusual case of retroperitoneal schwannoma (RS).
Incidence of acute cerebral infarction or space occupying lesion among patients with isolated dizziness and the role of D-dimer.
Hybrid Neurofibroma/Schwannoma of the Orbit.
Complete laparoscopic retrieval of inferior vena cava filter: A case report and literature review.
Retroperitoneal Leiomyosarcoma From the Radiologic Pathology Archives.
Inferior vena cava filter resulting in perforation and massive retroperitoneal hematoma presenting as acute onset of lower extremity weakness.
The purpose of this study is to determine if the Crux Vena Cava Filter System is safe and effective in preventing pulmonary embolism.
An area occupying the most posterior aspect of the ABDOMINAL CAVITY. It is bounded laterally by the borders of the quadratus lumborum muscles and extends from the DIAPHRAGM to the brim of the true PELVIS, where it continues as the pelvic extraperitoneal space.
Mechanical devices inserted in the inferior vena cava that prevent the migration of blood clots from deep venous thrombosis of the leg.

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Retrieved Text: In this schematic drawing of the circulatory system, note how the hepatic portal vein drains one set of the capillaries and leads to another set. A similar relationship exists in the kidneys.
Similarly, the liver helps regulate blood concentrations of recently absorbed amino acids and lipids by modifying their molecules into forms cells can use, by oxidizing them, or by changing them into storage forms. The liver also stores certain vitamins and detoxifies harmful substances.
Blood in the hepatic portal vein nearly always contains bacteria that have entered through intestinal capillaries. Large Kupffer cells lining the hepatic sinusoids phagocytize these microorganisms, removing them from the portal blood before it leaves the liver.
After passing through the hepatic sinusoids of the liver, the blood in the hepatic portal system travels through a series of merging vessels into hepatic veins. These veins empty into the inferior vena cava, returning the blood to the general circulation.
Other veins empty into the inferior vena cava as it ascends through the abdomen. They include the lumbar, gonadal, renal, suprarenal, and phrenic veins. These vessels drain regions that arteries with corresponding names supply.

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Retrieved Text: What Are the Causes of Unilateral Upper Limb Edema?
Unilateral upper limb edema refers to the swelling of the soft tissues of either the right or left arm or hand. Edema is more common in the legs and feet. If it occurs in the upper extremity, it is usually due to problems with drainage of the blood or lymph from the arm.
A deep vein thrombosis is a blood clot in one of the deep veins of the arms. They are more common when the limb is immobile for long periods of time. Some inherited blood disorders that predispose a person to clotting and some other diseases such as cancer. The blood clot impedes the return of blood to the heart from the arm, and fluid leaks out of the blood vessels into the tissues.
SVC syndrome is the abbreviation for superior vena cava syndrome. The superior vena cava is the vein that drains blood from the upper body back to the heart. In SVC syndrome, the vein is narrowed. The typical culprit is cancer. For example, the right lung abuts the superior vena cava. Lung cancer growing near the vein can compress it, causing blood to back up into the arm. In addition, the slow flowing blood can can cause blood to clot in an arm.
The lymphatic system drains fluid from the tissues and returns it to the venous system. Any disorder that interferes with the drainage of lymphatic fluid from the arm will cause unilateral upper extremity edema. In breast cancer, the lymph nodes of the arm

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Retrieved Text: TWO-PIECE MODEL OPENS IN HALF TO SHOW INNER CHAMBERS AND VALVES OF THE HEART AS WELL AS AORTIC ARCH, SUPERIOR AND INFERIOR VENA CAVA, PULMONARY AND CARDIAC VEINS. 3-3/4" X 4" X 4-1/4". CARD SIZE: 6-1/2" X 5-1/4".

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Retrieved Text: Copyright: © 2016 Habib M. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
The incidence of complete heart block following Glenn’s shunt is not known. Complete heart block may occur immediately after surgery or early in the postoperative period and also may occur many months or years after surgery. Implantation of epicardial leads was considered undesirable because of the previous thoracic surgery.
We present a case of cyanotic heart disease, post Bidirectional Glenn’s shunt. with single ventricle and supravalvular pulmonary stenosis who had symptomatic complete heart block and required permanent pacemaker implantation.
A connection between the superior vena cava and the right pulmonary artery is known as Glenn’s shunt. Since the late 1950s, the Glenn’s shunt has been performed to improve pulmonary blood flow in patients with cyanotic congenital heart disease. Venous access to the right ventricle was complicated by the loss of continuity between the right atrium and superior vena cava consequent on the previous surgery .
A superior vena cava connection to pulmonary artery (Glenn shunt) is currently the initial surgical step toward creating a total cavo-pulmonary connection (Fontan operation) in patients with a functionally univentricular heart. Subsequently, a total cavo-pulmonary connection is completed by tunnel that directs the inferior vena cava flow into the superior cavo-pulmonary anastomosis. In some patients, the superior cavo-pulmonary connection remains the definitive palliative procedure when completion of the total cavo-pulmonary anastomosis is deemed to be inappropriate. These

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Rank: 24
Score: 88.86822
Retrieved Text: Persistent left superior vena cava (PLSVC) is a structural, asymptomatic, and infrequent anomaly, present in 0.3% of the general population and in 4.3% of congenital heart disease. Typically, the diagnosis reveals itself unexpectedly at the time of device implantations. Isolated PLSVC (PLSVC with absent right SVC [RSVC]) is usually asymptomatic, but it can pose difficulties with central venous access, device implantation, and cardiothoracic surgery. This condition is also associated with an increased incidence of congenital heart disease, arrhythmias, and conduction disturbances. Successful implantation of a permanent pacemaker from right subclavian route was done in a 70-year-old male patient with isolated PLSVC.
A 70-year-old male was admitted in our institution with a complaint of recurrent syncope for 10 days duration. A 12-lead electrocardiography revealed complete heart block (CHB). The probable etiology of CHB was kept as degenerative, after ruling out reversible causes. Temporary pacemaker lead was inserted uneventfully by femoral route. As per the government's funding scheme, the only option for permanent pacemaker implantation was single chamber VVI. Due to large experience of our institution, right subclavian approach was used. After puncture of right subclavian vein, it was impossible to advance a guidewire into the normal expected course of SVC, under fluoroscopy, the wire always being seen to coil in the left subclavian vein (LSCV) and guidewire to pass through left-sided SVC. A 9-French pacemaker sheath was inserted by modified Seldinger technique. On lead insertion, circuitous course of the lead via left mediastinum (PLSVC), instead of the expected right side, was noted [Figure 1]. Right upper limb venography

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Rank: 25
Score: 88.691925
Retrieved Text: Dr. Princewill is a Resident Physician in the Department of Diagnostic Radiology and Nuclear Medicine at the University of Maryland School of Medicine, Baltimore, MD; Dr. Awan is a Resident Physician at the University of Maryland School of Medicine, Baltimore, MD; Dr. Ali is a Resident Physician at the Christiana Care Health System, Newark, DE; Dr. Y. Awan is a Resident Physician at the George Washington University School of Medicine, Washington, D.C.; and Dr. Iliescu is an Interventional Radiologist at the University of Maryland School of Medicine, Baltimore, MD.
Deep venous thrombosis generally develops within the deep veins of the lower extremities, but it can arise from pelvic or even upper extremity veins. In the mid-19th century, Virchow explained the etiology of DVT to include the triad of venous stasis, intimal injury, and hypercoagulability. Thus, risk factors for DVT include, but are not limited to, prolonged immobilization, such as with prolonged travel and after surgery, hypercoagulable states, neoplasm, pregnancy, and estrogen therapy. Genetic predisposition and advanced age (>50) are also associated risk factors. Once a thrombus is formed in the deep veins of the body, it is susceptible to embolizing into the pulmonary arteries.
Systemic anticoagulation is the therapy of choice for all forms of DVT, and initiation of therapy can reduce the mortality rate from 30% to 8%,2 making PE one of the most preventable causes of in-hospital mortality. Common pharmacological agents utilized include heparin and warfarin. However, anticoagulation may be contraindicated in a subgroup of patients due to several reasons, including bleeding diathesis, active bleeding, recent

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Rank: 26
Score: 88.561806
Retrieved Text: Description: Right heart and left heart catheterization by way of right femoral artery, right femoral vein, and right internal jugular vein.
PRECATHETERIZATION DIAGNOSIS (ES): Hypoplastic left heart, status post Norwood procedure and Glenn shunt.
2. Left pulmonary artery hypoplasia.
3. Diminished right ventricular systolic function.
6. Flow to right upper lobe more than left upper lobe from collaterals arising from branches of the aortic arch.
PROCEDURE (S): Right heart and left heart catheterization by way of right femoral artery, right femoral vein, and right internal jugular vein.
I. PROCEDURES: XXXXXX was brought to the catheterization lab and was anesthetized by anesthesia. He was intubated. His supplemental oxygen was weaned to 24%, on which all of his hemodynamics were obtained. The patient was prepped and draped in the routine sterile fashion, including both groins and the right neck. Xylocaine was administered in the right femoral area. A 6-French sheath was introduced into the right femoral vein percutaneously without complication. A 4-French sheath was introduced into the right femoral artery percutaneously without complication. A 4-French pigtail catheter was introduced and passed to the abdominal aorta.
Dr. Hayes, using the SiteRite device, introduced a 5-French sheath into the right internal jugular vein without complication.
A 5-French wedge catheter was introduced through the sheath in the right internal jugular vein and was passed to the left pulmonary artery and further to the left pulmonary capillary wedge position. This catheter would not pass to the right pulmonary artery. The wedge catheter was removed. A 5-French IMA catheter was then introduced and passed to the right pulmonary artery. After right

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Rank: 27
Score: 87.89997
Retrieved Text: On the right lung,, immediately above the hilus, is an arched furrow which accommodates the azygos vein (Groove for azygos vein); while running upward, and then arching lateralward some little distance below the apex, is a wide groove for the superior vena cava (Groove for superior vena cava) and right innominate vein (Groove for brachiocephalic vein); behind this, and nearer the apex, is a furrow for the innominate artery. Behind the hilus and the attachment of the pulmonary ligament is a vertical groove for the esophagus (Groove for esophagus); this groove becomes less distinct below, owing to the inclination of the lower part of the esophagus to the left of the middle line. In front and to the right of the lower part of the esophageal groove is a deep concavity for the extrapericardiac portion of the thoracic part of the inferior vena cava (Groove for inferior vena cava).

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Rank: 28
Score: 87.718864
Retrieved Text: Cook IVC Filter Lawsuit Filings Allege Cook Medical’s Blood Clot Filters Have Defects That Cause Fracturing, Puncturing The Lungs, Heart, And Inferior Vena Cava And Migrating.
“We intend to monitor this bellwether trial closely to see how jurors respond to the evidence presented during trial,” says Dr. François Blaudeau, founder of Southern Med Law.
Southern Med Law attorneys are currently evaluating legal claims on behalf of patients who experienced IVC filter side effects, including perforation of the heart, lung, and vena cava and death. If you believe you have been injured by IVC filters, contact Southern Med Law for a free legal evaluation by calling (205) 547-5525 or visit southernmedlaw.com for more information on this and other defective medical devices and to fill out a contact form.
Retrievable Inferior Vena Cava filters are small, cage-like devices implanted in the vena cava, a major vein that returns blood from the lower half of the body to the heart. The filters catch blood clots that travel from the lower part of the body to the heart and lungs to prevent them causing a pulmonary embolism. The devices are implanted in patients who cannot take anticoagulants and those who found blood thinners ineffective.
The U.S. Food and Drug and Administration (FDA) has received hundreds of adverse event reports over IVC filters since 2005. The reports included device migration, filter fracture, perforation of the IVC filter, difficulty removing the device, and embolization, which is movement of the entire filter or fracture fragments to the heart or lungs. These types of events may be related

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Rank: 29
Score: 87.09881
Retrieved Text: As the largest vein in the human body, the inferior vena cava is responsible for carrying deoxygenated blood from the lower extremities to the heart. Yet, when individuals are recovering from accidents or surgery and cannot take an anticoagulant drug to prevent blood clotting, a filter is often inserted into the vein to capture blood clots before they reach the lungs (pulmonary embolism) or heart. Originally approved in 1979 by the FDA, the Inferior Vena Cava Filter, or IVC Filter, can be retrievable or permanent. Unfortunately, there are increasing reports of serious injuries related to IVC filters, resulting in multiple lawsuits against manufacturers defective medical devices.
Injuries from IVC Filters are classified as procedural, delayed or retrieval. In other words, complications may arise during insertion of the filter, causing bleeding or bruising or even blood vessel puncture. The filter also may be placed incorrectly. In cases where doctors remove the filter, large clots and heavy scarring have prevented its removal. Even so, other injuries are noted while the filter is in the body, including filter fracture or breakage, migration of the filter, infection and perforated organs. In extreme instances, patients have suffered from IVC filter embolization, where debris from a broken filter travels through the blood and becomes lodged in organs. Without question, this can result in death.
If you or someone you love has been injured or has died due to complications from an IVC Filter, you need to know your legal options. You may be entitled to compensation. The personal injury and defective device lawyers at

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======= Instance Index 3371 =========
Input Text: Answer the following question given this paragraph: 

The orbicularis oris is a circular muscle that moves the lips, and the orbicularis oculi is a circular muscle that closes the eye. The occipitofrontalis muscle moves up the scalp and eyebrows. The muscle has a frontal belly and an occipital (near the occipital bone on the posterior part of the skull) belly. In other words, there is a muscle on the forehead ( frontalis) and one on the back of the head ( occipitalis), but there is no muscle across the top of the head. Instead, the two bellies are connected by a broad tendon called the epicranial aponeurosis, or galea aponeurosis (galea = “apple”). The physicians originally studying human anatomy thought the skull looked like an apple. The majority of the face is composed of the buccinator muscle, which compresses the cheek. This muscle allows you to whistle, blow, and suck; and it contributes to the action of chewing. There are several small facial muscles, one of which is the corrugator supercilii, which is the prime mover of the eyebrows. Place your finger on your eyebrows at the point of the bridge of the nose. Raise your eyebrows as if you were surprised and lower your eyebrows as if you were frowning. With these movements, you can feel the action of the corrugator supercilli. Additional muscles of facial expression are presented in Figure 11.8.


Q: The orbicularis oris is a circular muscle that moves the lips, and the orbicularis oculi is a circular muscle that does what?

 Choices:

- closes the eye

- opens the eye

- moisturizes the eye

- pressure the eye

A:

Target Text: closes the eye

#### Retrieved Documents ####

Rank: 0
Score: 110.781845
Retrieved Text: In human anatomy, the orbicularis oris muscle is the sphincter muscle around the mouth. "Orbicularis Oris is a complex of muscles in the lips that encircle the mouth; until recently it was misinterpreted as a sphincter, or circular muscle, but it is actually composed of four independent quadrants that interlace and give only an appearance of circularity.'' It is also one of the muscles used in the playing of all brass instruments and some woodwind instruments. This muscle closes the mouth and puckers the lips when it contracts.

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Retrieved Text: Origin = usually the end of the muscle attached to the bone that doesn’t move.
Insertion = usually the end of the muscle that’s attached to the bone that moves.
The muscles of the face are very unusual cause they don’t move bone but skin. The muscles connect to the skin and other muscles.
The occipitofrontalis is also known as the epicranius. It’s very obvious in its name as the occipital belly covers the occipital bone and the frontal belly covers the frontal bone. This muscle has two bellies and this is an unusual muscle not only because of that but it is connected by a giant tendon called the aponeurotica which covers the top of your skull. This is the muscle that helps you raise eye brows and anchor the aponeurosis.
The origin of the frontal belly is the aponeurotica and the insertion is the skin of the eye brows. The origin of the occipital belly is the occipital bone while the insertion is the aponeurotica.
Orbicularis means circular muscle and oculi means eye. This is a circular (sphincter) muscle that goes around the eye. Fibers anchor the frontal bone and maxillary bone and inserts into the eyelid so that when it contracts it closes the eye.
When this sphincter muscle contracts, your eye lids close.
The nasalis muscle is what helps you flare your nostrils and “depress the bridge of the nose.” The origin is the maxilla and the insertion is the dorsum of the nose which is literally the top of the bone.
The origin is the zygomatic bone (the cheek

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Score: 88.93452
Retrieved Text: Orbicularis oculi muscle fibers are relatively short and heterogeneous in length.
Department of Ophthalmology, University of Minnesota 55455, USA.
T Lander, J D Wirtschafter, L K McLoon; Orbicularis oculi muscle fibers are relatively short and heterogeneous in length.. Invest. Ophthalmol. Vis. Sci. 1996;37(9):1732-1739.
PURPOSE: The anatomy of individual myofibers within the orbicularis oculi muscle was examined to determine individual myofiber lengths in the different regions of the muscle. A wide variety of eyelid conditions require eyelid surgery or drug injections directly into the eyelid. Knowledge of regional myofiber anatomy and physiology is important for accurate treatment of these conditions. METHODS: Eyelid specimens from rabbits were treated with collagenase, fixed, and stained for neuromuscular junction location. Individual myofibers were dissected from these muscle specimens and were measured to determine individual myofiber length and neuromuscular junction position. Additional eyelid specimens of rabbits and humans were stained en bloc to visualize neuromuscular junction location in the pretarsal and preseptal regions of the orbicularis oculi muscle. RESULTS: The myofibers showed variable lengths, shorter in the pretarsal region of the muscle and longer in the preseptal region. The average individual myofiber length in the pretarsal region was 36% as long as the entire length of the pretarsal muscle region. In the preseptal region, the myofibers were slightly longer, covering 54% of the entire length of this region of the muscle. In both the pretarsal and preseptal regions of the rabbit and human orbicularis oculi muscle, there were many clusters of neuromuscular junctions throughout the medial to lateral length of the muscle, with the majority

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Score: 84.05615
Retrieved Text: contraction of the orbicularis oculi muscle induced by electrical or mechanical stimulation of the supraorbital nerve.
Daniel J., U.S. neurologist, 1874-1958.
McCarthy scales of children's abilities - used to test children's comprehension between 2-1/2 and 8-1/2 years of age.
Contraction of orbicularis oculi muscle induced by electrical or mechanical stimulation of supraorbital nerve.

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Rank: 4
Score: 80.86446
Retrieved Text: Botox is used by doctors to eliminate fine lines and wrinkles as well as treat conditions such as chronic migraines, overactive bladder and severe underarm sweating. While Botox works well to improve smile lines, frown lines between the eyes and crow’s feet along the sides of the eyes, can it also be used to plump the lips of patients?
Before having Botox to plump the lips, it is important to understand that Botox does not have the same advantages as dermal filler even though it can be injected into areas of the lips to make them appear fuller.
Botox is a neurotoxin which works by relaxing or temporarily paralyzing the muscle it is injected into on a patient. Therefore, the muscle under the expression lines moves less which allows the wrinkles above them to smooth out. When it comes to the lips, the muscle that is responsible for closing, protruding or compressing the lips against the teeth is called the orbicularis oris. When Botox is injected into two precise spots along the vermillion border located just above the lips the upper orbicularis oris relaxes. This relaxation causes the upper lip to slightly flip or curve upward and appear plumper. It is crucial that the cosmetic doctor is adequately skilled with lip injections because improper injection can cause the lip to flatten instead of plumping.
Botox is great for adding a little extra pout but it cannot give larger results like fillers provide. However, Botox can give instant plumping without the side effects of redness, rash and swelling. The procedure

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Rank: 5
Score: 78.93676
Retrieved Text: The thin, flat muscle forming the wall of the cheek.
a thin, flat muscle of the cheek region, the action of which contracts and compresses the cheek.
The applicability of the protocol was made through the anatomo-functional observation of the static structures (maxilla, mandible, TMJ and dental arches) and dynamic structures (masseter, buccinator, and mentual muscles, lips and tongue) of the stomatognathic system, palpation, counter-resistance using wooden spatula, verbal commands of mobility (opening, closure, protrusion, retraction, lateralization and vibration) and facial measurement using a 150mm plastic caliper/ 6 in.
Salivary gland choristoma in the buccinator muscle: A case report and literature review.
The orbicularis oculi, corrugator supercilii, platysma, mentalis, and buccinator are the most preferred muscles for injection (4).
10 700 6955 buccinator Sandhill Crane 3763 2446 Grus canadensis * G.
The artery is superficial to the mandible, buccinator muscle, and levator anguli oris muscle.
But in our present case, an intrinsic weakness in buccinator muscle coupled with tear in mucous membrane might be responsible for the condition.
Blunt dissection was performed with caution through the buccinator muscle.
The probe tip was placed on the cheek ~10-15 mm lateral to the lip angle, avoiding natural creases in the skin when the underlying muscles (risorius, buccinator, platysma) contracted (Figure 1(d)).
The weight of the buccinator muscles is no longer opposed, by the mass of the tongue, and thus unequal forces are created, which place constrictive forces on the palate.
Next is the buccinator, a smaller muscle that puffs out the cheek (Fig 1), then the masseter is superimposed, a large muscle used for grinding, the one that bulges

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Retrieved Text: For people who suffer frequent headaches or sinus pressure, massage for the muscles of the eyes may provide relief of symptoms.
Using the image above as a reference, structures to keep in mind while assessing and treating patients suffering from headaches may include neurovascular structures and investing fascia of: the frontalis muscle (FM), oblique head of the corrugator supercilii (CSMO), transverse head of the corrugator supercilii (CSM-T), depressor supercilii (DSM), procerus (PM), medial head of the orbicularis oculi (MOOM), the orbital portion of the orbicularis oculi (OOOM), and the temporalis (TM) muscle.
Beer et al. (2016). Three-dimensional Facial Anatomy: Structure and Function as It Relates to Injectable Neuromodulators and Soft Tissue Fillers. Plast Reconstr Surg Glob Open.
Janis et al. (2017). Targeted Peripheral Nerve-directed Onabotulinumtoxin A Injection for Effective Long-term Therapy for Migraine Headache. Plast Reconstr Surg Glob Open.
Lee, H.J., Choi, K.S., Won, S.Y., ... Kim, H.J. (2015). Topographic Relationship between the Supratrochlear Nerve and Corrugator Supercilii Muscle--Can This Anatomical Knowledge Improve the Response to Botulinum Toxin Injections in Chronic Migraine? Toxins (Basel).

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Rank: 7
Score: 76.38088
Retrieved Text: Figure 10.6 Lateral view of muscles of the scalp, face, and neck.
1 Figure 10.6 Lateral view of muscles of the scalp, face, and neck.
2 Figure 10.13a Superficial muscles of the thorax and shoulder acting on the scapula and arm.
4 Figure 10.11a Muscles of the abdominal wall.
5 Figure 10.13c Superficial muscles of the thorax and shoulder acting on the scapula and arm.
8 Figure 10.19a Anterior and medial muscles promoting movements of the thigh and leg.
9 Figure 10.20a Posterior muscles of the right hip and thigh.
10 Figure 10.21a Muscles of the anterior compartment of the right leg.
11 Figure 10.22a Muscles of the lateral compartment of the right leg.
12 Figure 10.4 Anterior view of superficial muscles of the body.
13 Figure 10.5 Posterior view of superficial muscles of the body.
Download ppt "Figure 10.6 Lateral view of muscles of the scalp, face, and neck."
Entry Task: Make a table. One side with three concentric movements, one side with three eccentric movements.
MUSCLES OF THE BODY You need to be able to know the location and action of these muscles!!!
Frontalis Orbicularis Oculi Levator Labii Superioris Zygomaticus Minor and Major Orbicularis Oris Masseter Platysma Occipitalis Temporalis Sternocleidomastoid.
Steven lee M.S. Pathology FTCC.
The general doctrine of muscle.
THE MUSCULAR SYSTEM 1. How do skeletal muscles produce movement?

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Rank: 8
Score: 71.479675
Retrieved Text: An edge loop, in computer graphics, can loosely be defined as a set of connected edges across a surface. Usually the last edge meets again with the first edge, thus forming a loop. The set or string of edges can for example be the outer edges of a flat surface or the edges surrounding a 'hole' in a surface.
In a stricter sense an edge loop is defined as a set of edges where the loop follows the middle edge in every 'four way junction'. The loop will end when it encounters another type of junction (three or five way for example). Take an edge on a mesh surface for example, say at one end of the edge it connects with three other edges, making a four way junction. If you follow the middle 'road' each time you would either end up with a completed loop or the edge loop would end at another type of junction.
Edge loops are especially practical in organic models which need to be animated. In organic modeling edge loops play a vital role in proper deformation of the mesh. A properly modeled mesh will take into careful consideration the placement and termination of these edge loops. Generally edge loops follow the structure and contour of the muscles that they mimic. For example, in modeling a human face edge loops should follow the orbicularis oculi muscle around the eyes and the orbicularis oris muscle around the mouth. The hope is that by mimicking the way the muscles are formed they also aid in

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Rank: 9
Score: 71.237854
Retrieved Text: BOTOX® (onabotulinumtoxinA) is part of a group of drugs known as biologics—biologic med icines are made from living things. BOTOX® is a purified protein that is made from a type of bacteria called Clostridium botulinum type A.
BOTOX® targets one of the underlying causes of frown lines and crow’s feet—the repeated muscle contractions from frowning and squinting over the years. Your provider will inject these muscles with BOTOX® to temporarily reduce muscle activity.
BOTOX® targets one of the underlying causes of frown lines and crow’s feet—the repeated muscle contractions from frowning and squinting over the years. Your provider will inject these muscles with BOTOX® to temporarily reduce muscle activity. You will begin to notice a visible smoothing of your crow’s feet lines and frown lines between your brows.
For the crow’s feet area, your provider will inject 3 areas of the orbicularis oculi, the muscle that frames the side of the eye. This will be repeated on the orbicularis oculi muscle on the other eye.
Injecting BOTOX® into the muscles that cause crow’s feet lines temporarily reduces the activity of those muscles. The result is a reduction in the appearance of those lines.
For the frown lines area, your provider will administer 5 injections into muscles in your forehead, depending on the severity of the wrinkles and the patients concerns.
Injecting BOTOX® into the muscles that cause frown lines temporarily reduces the activity of those muscles. The result is a reduction in the appearance of those lines.
Fine lines and wrinkles is something EVERY women AND MAN have to deal with during the

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Rank: 10
Score: 71.17724
Retrieved Text: The levator labii superioris pulls the upper lip into a squared-off shape, the mouth of disgust. The sneering muscle pulls on the mouth indirectly: None of its strands attaches to the lips themselves. Instead, it attaches to the circular muscle of the lips (A), the nose wing, and the upper nasolabial fold (B). The upward pull on the skin and muscle surrounding the lips drags the lips upward as well. There are three independent sections, which can all accomplish the same task: The nasal branch is fixed alongside the upper nose (C); the middle branch is fixed underneath the eye socket (D). The last section, zygomatic minor, is treated by some anatomists as a separate muscle. It attaches on the corner of the cheekbone (E).
look a great deal different depending on which branch is contracting. We'll describe the common element—the mouth—first, then look at the differences between the branches.
The line between a sneering and a relaxed upper lip can be a fine one. Artists occasionally find themselves struggling to take the sneer out of a mouth without quite knowing how it got there. What should they know that would help them?
First, don't bother redrawing the lower lip. The sneer only affects the upper lip, leaving the lower just the same. Second, watch the line of the upper-lip margin. The basic effect of the sneer is the same as pushing your upper lip flat against a piece of glass. The lip is flattened, pushed back, and widened. This changes the upper margin from "stretched M" to "square

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Score: 71.13717
Retrieved Text: Apart from being the largest organ in the body, skin is also responsible for preventing bacteria, covering organs in the body, maintaining body temperature, acting as sensory receptors, and all the way to preventing water loss to keep the skin hydrated. However, once we get older, our skin that was once smooth and firm will gradually become loose, with the appearance of fine lines and wrinkles.
1. Epidermis is 0.7 mm in depth.
It is the outermost layer of the skin that is responsible for protecting the skin from external factors, such as sun light. Its main function is to exfoliate dead cells, which then become scurf on the skin. It comprises of 4 semi layers that include basal, spinuous, granular, stratum corneum layers. The skin cells will move from the bottom most layer to the upper most layer, where they will be eventually exfoliated. This cycle takes about 30-40 days. If the skin cells become atrophic, there may be the appearance of fine lines and the skin may become dry. This is the layer of skin that is commonly treated by applying nourishing cream.
2. Dermis is 1.5 mm. in depth.
This layer of skin is the thickest of all the layers. It consists of collagen, elastin, fat, blood vessels, and oxygen that nourish the skin. Once we get older, along with the exposure to pollution, these components will vanish with age and with slower rate of reproduction, resulting in the appearance of wrinkles that cannot be covered with any cosmetics or treated with any cream.
3. Hypodermis is 3.0mm

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Retrieved Text: When done with educated precision, Botox is a brilliant and powerful tool that eliminates wrinkles from the face. Lines between the eyes, in the forehead and those nasty crow’s feet’ by the eyes soften in about five days and the effects last several months. But when Botox is injected incorrectly, get ready for a big nightmare. Bad Botox injections cause uneven facial features and a startling plastic look that wipes natural expression from the face.
Botox is a type of neuromodulator that relaxes muscles to soften and eliminate certain lines and creases. Relaxing these muscles effectively flattens out that area of skin giving a more youthful and aesthetically pleasing appearance.
Contrary to rumor, Botox properly used does not “freeze the face” and eliminate its expressiveness. Here again, achievement of a natural-looking result is as much art as science. The objective is not simply youthfulness, but a youthfulness in accord with the individual face. Botox injections should be done very gently and carefully so as to prevent damage and deep lines; it can be very precisely filtrated and calibrated to the needs of the client. It is of special importance to actors (although really no less so to the rest of us) that the face remain fully animated and expressive.
Botox can be administered at Dr. Kanodia’s office by appointment only. Before your appointment the injection will be freshly prepared to ensure optimal results. Next, Dr. Kanodia will consult with you and discuss your concerns as well as inspecting the areas to be injected. Once deciding on the proper areas

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Rank: 13
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Retrieved Text: Wrinkle Decreasing Treatments targets one of the underlying causes of frown lines and crow’s feet—the repeated muscle contractions from frowning and squinting over the years. Jayne our expert injector will treat these muscles with "Wrinkle Decreasing Treatments" to temporarily reduce muscle activity. You will begin to notice a visible smoothing of your crow’s feet lines and frown lines between your brows.
Wrinkle Decreasing Treatments work beneath the skin’s surface and targets the underlying muscle activity that causes frown lines and crow’s feet.
For the crow’s feet area, Jayne will inject 3 areas of the orbicularis oculi, the muscle that frames the side of the eye. This will be repeated on the orbicularis oculi muscle on the other eye.
Injecting "Wrinkle Decreasing Treatments" into the muscles that cause crow’s feet lines temporarily reduces the activity of those muscles. The result is a reduction in the appearance of those lines.
For the frown lines area, Jayne will administer 5 injections into muscles in your forehead—1 in the procerus muscle and 4 in the corrugator muscles.
Injecting "Wrinkle Decreasing Treatment" into the muscles that cause frown lines temporarily reduces the activity of those muscles. The result is a reduction in the appearance of those lines. It is the patients impression of treatment that is of most important to them. That's why Jayne Expert injector at The Lip Queen will work with you to help you achieve your desired outcome.
WE ONLY USE BOTOX BY ALLERGAN for PROVEN LASTING RESULTS.
We pride ourselves on using only a small number of top end brand/prescribed products which are effective,

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Score: 70.107
Retrieved Text: Paradoxical (synkinetic) movements of the upper lids constitute a rare type of congenital anomaly, noted in association with movements of either extra-ocular muscles or the muscles of mastication (external pterygoids). These movements are outside the volition of the patient and termed 'associated reflexes of misdirection'. Marcus-Gunn (M-G) jaw-winking phenomenon is the most common congenital synkinetic movement. When the mouth is opened or the jaw is moved laterally, the ptotic eyelid elevates. This results from a congenital, aberrant connection between the trigeminal nerve controlling mastication and the oculomotor nerve supplying the levator. In inverse M-G phenomenon the upper lid falls to cover the eye with movements of mastication. This is more commonly seen as an acquired rather than congenital anomaly in central nervous system (CNS) disease. This has to be differentiated from facial synkinesis following seventh nerve paresis.
A 20-year old male patient presented with drooping of left upper lid since birth and defective vision in left eye since 6 years. He was moderately built and well nourished. On refraction, his best-corrected visual acuity was 6/6, N6 in each eye. Both eyes showed horizontal widening of palpebral fissure (35 mm) as in euryblepharon. He had a mild chin elevation.
Extraocular movements were full in right eye but the left eye showed restriction of elevation and abduction by 15° (Hess screen). There was 4 mm ptosis in the left eye along with 15° hypotropia. On fixing with left eye, there was no change in the amount of ptosis. The left eye was found suppressed in Worth's four dot test. The

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Score: 65.64441
Retrieved Text: The nasalis is a muscle of the nose that contracts and dilates the nasal cartilages. It is made up of two parts, transverse/compressor and alar/dilator parts. It is structurally similar to a sphincter.
The muscle arises in the maxilla part of the skull and attaches within the nasal bone. The nasalis muscle is made up of two parts: the transverse and the alar.
The transverse part also known as compressor naris emerges superiorly and laterally towards the incisive fossa via the maxilla; its fibers continue superiorly and medially, spreading into a thin aponeurosis which is constant on the bridge of the nose and the muscle of the opposite side. It compresses the nostrils and may completely close them.
The alar part part also known as dilator nasalis emerges via the maxilla superior towards the lateral incisor. Its medial fibres are likely to blend with the depressor septi.
Transverse part – It is constant with the same muscle of the other side of the face. The two muscles merge superior towards the middle segment of the anterior margin of the nose over the cartilaginous portion.
The skin on the posterior end of the wing of the nose.
The skin at the posterior margin of the nostril.
The skin of the mobile septum of the nose at the midline.
The transverse part of the nasalis is a slim muscle which hooks.
Posterior towards the wing of the nose.
Deep towards the levator labii superioris alaeque nasi.
Near the skull and then widens into a triangular shape as it travels superiorly, anteriorly, and medially on the side of the nose.
It

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Rank: 16
Score: 65.095
Retrieved Text: The mid face is the area lying between the bicanthal and oral commissure. The mid face is one of the first facial areas to show signs of aging. As individuals age, the bony skeleton and soft tissues of the face lose volume, producing a slightly wider orbital aperture and less anterior projection. This decreases the overall projection of the cheek and diminishes bony support for the overlying soft tissue structures. The preseptal orbicularis oculi muscle loses tone, resulting in herniation of the intraorbital fat.
Ptosis of midfacial adiposity exposes the inferior orbital rim. Further descent of cheek fat and separation from the suborbicularis oculi fat (SOOF) can be heralded by a faint diagonal groove in the infraorbital area parallel to the nasolabial crease. Furthermore, descent of the Bichat fat pad over the upper mandible can increase lower facial jowling.
Individuals in their early 30s may have descent of the malar fat pad; this may lead to the formation of infraorbital dark circles and deepening of the nasolabial and nasojugal (tear trough) creases. These changes occur earlier in the presence of poor bony support and midface retrusion.
During the past 15 years, several techniques have been described to specifically address the mid face, since this area is not addressed with standard cervicofacial rhytidectomy. Presently, restoration of cheek contour and volume can be achieved by performing a subperiosteal, vertically oriented lift with independent suspension of the various cheek structures. The lift can be performed with small and hidden incisions and supplemented with a cheek implant if deemed necessary.
Early in the authors’

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Retrieved Text: Long-Term Outcome of Microautologous Fat Transplantation to Correct Temporal Depression.
Micro-autologous Fat Transplantation (MAFT) for Forehead Volumizing and Contouring.
Microautologous Fat Transplantation for Primary Augmentation Rhinoplasty: LongTerm Monitoring of 198 Asian Patients.
Fat Grafting for Recontouring Sunken Upper Eyelids With Multiple Folds in AsiansNovel Mechanism for Neoformation of Double Eyelid Crease.
A Secure Technique for Microvascular Anastomosis in Arteries with Intimal Dissection: Intimal Sleeve Fold-Over Technique.
A practical guide to free tissue transfer.
In situ pedicle lengthening of the anterolateral thigh flap.
The role of frontalis orbicularis oculi muscle flap for correction of blepharoptosis with poor levator function.
Angular artery cutaneous flap for reconstruction of difficult oronasal fistulas.

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Retrieved Text: Through cutting edge research, Optalert has discovered the biomarker for drowsiness, an association between brain function and eyelid movement. A blink is the highly coordinated interaction of two muscle groups, the orbicularis oculi (OO) and the levator palpebrae superioris (LPS). Each muscle is controlled from different centres in the brain, of which activities need to be co-ordinated precisely. When drowsiness occurs, the tight controls responsible for their synchronisation deteriorates and this is evident in the blink characteristics.
Using sophisticated analysis techniques, Optalert created the only scientifically proven, objective measurement of drowsiness; the Johns Drowsiness Scale (JDS).
The Optalert BlinQ system offers a combination of real-world evidence and clinical data, adaptable to various pharmaceutical trials and research projects.
Example of Eye movement data.
Similar to an EEG or ECG, blinks are involuntary movements that reveal much about your health.
The use of Optalert’s innovative technology provides informative data to enable a greater level of understanding of drug or intervention effects and a way forward to developing life-saving drugs, faster.
Contact us today, if you’d like to learn more about how Optalert can fast track your clinical drug trials.

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Rank: 19
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Retrieved Text: What Do You Know About Face Lift?
A facelift, actually known as a rhytidectomy, is a sort of corrective surgery or facial conditioning technique used to give a more energetic facial appearance. There are various surgical strategies and exercise schedules. Surgery for the most part includes the expulsion of abundance facial skin, with or without the fixing of fundamental tissues, and the redraping of the skin on the patient’s face and neck. Exercise schedules tone hidden facial muscles without surgery. Surgical facelifts are viably consolidated with eyelid surgery and other facial systems and are ordinarily performed under general anesthesia or profound sundown rest.
As indicated by the latest 2011 measurements from the American Society for Esthetic Plastic Surgery, facelifts were the 6th most well known stylish surgery performed after liposuction, bosom expansion, abdominoplasty (tummy tuck), blepharoplasty (eyelid surgery) and bosom lift.
A facelift is performed to revive the presence of the face. Maturing of the face is most appeared by an adjustment in position of the profound anatomical structures, strikingly the platysma muscle, cheek fat and the orbicularis oculi muscle. These pave the way to three milestones specifically, an appearance of the cheek (a broken jaw line by ptosis of the platysma muscle), expanded excess of the nasolabial overlap (caused by a plummet of cheek fat) and the expanded separation from the ciliary edge to the mediocre most purpose of the orbicularis oculi muscle (caused by diminishing tone of the orbicularis oculi muscle).The skin is a fourth segment in the maturing of the face. The perfect age for cosmetic

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Rank: 20
Score: 60.709003
Retrieved Text: How does it correct wrinkles?
A certified injector who understands the facial anatomy will carry on the procedure. Botox treatment is available in different sets such as plastic surgery or medical spa. In Albany Cosmetic and Laser center, firstly, Dr. Kamal, a master cosmetic injector, maps your face and discuss the procedure in details. The object of Botox treatment in Edmonton is to remove aging marks such as frown lines, forehead lines, and smile lines from your face.
If you are new to Cosmetic injectables including Botox, then you must have lots of questions. This simple infographic chart shows the facial wrinkles and sign of aging that we, frequently, treat this injection. Moreover, the other two charts show the type of wrinkles and the corresponding muscles.
What are the Differences between Filler and Botox?
Have you ever asked yourself what is the difference between the two injection types? If yes, then you are not alone, as this is the most frequent questions that we get from our clients, as they are usually confused between the two famous cosmetic injectables.
It helps to reduce the muscle contract, therefore it treats facial wrinkles саuѕеd by a muѕсlеѕ оr fасіаl expression. If a person rаіѕеѕ thеіr еуеbrоwѕ, it causes horizontal lines. Also, if a person frоwnѕ іt саuѕеѕ vеrtісаl lіnеѕ, whісh makes a реrѕоn lооk sad оr unhappy. Thеѕе muscles аrе dоіng nоthіng еlѕе, аnd реорlе dоn't need thеm. That said, The toxin weakens them аnd ѕtорѕ them frоm mаkіng thоѕе lines and wrinkles. It usually takes 3 days to start seeing results and

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Rank: 21
Score: 60.311516
Retrieved Text: Lines that etch vertically from the upper or lower lips are commonly called lipstick lines or smoker lines. These lines are more prevalent on the upper lips. At Castleknock Cosmetic Clinic Dublin we know that lip lines are sometimes called smoker’s lines, most individuals develop the lines for reasons other than smoking. The lines are a result of loss of volume that occurs with age, along with repetitive bunching of the tissue from muscular activity. These lines can contribute to lipstick bleeding, hence the name ‘lipstick lines’.
At Castleknock Cosmetic Clinic Dublin we typically treat lipstick lines with advanced dermal fillers, toxin muscle relaxing injections or a combination of both. The depth of the lines and extent of puckering will influence treatment modalities. It is very common to use toxin muscle relaxing injections to treat lipstick lines regardless of the depth of the lines. Toxin injections will have a couple of positive effects on the lines over time. First, the toxin relaxing injection will help relax the lines, which tends to eliminate the more permanent etching that may have occurred. Secondly, it will help extend the longevity of the advanced dermal fillers. Toxin muscle relaxing injection is generally placed at certain points in the orbicularis oris muscle which surrounds the mouth, including the area of the vermilion border of the lips.
If the lines are a little deeper, then we will place a soft, smooth dermal filler such as Restylane, Juvéderm or Belotero along the lines to help fill them in. Also we may place a dermal filler

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Rank: 22
Score: 59.748726
Retrieved Text: The muscles of the eye are integral to its function and motion. Muscles directly associated with the eye include the extraocular muscles which control the external movement of the eye; the intraocular muscles, which are responsible for pupil accommodation and reaction to light; and the protractor and retractors of the eyelids. Deficits in the muscles or the nerves innervating these muscles can result in functional impairment of the involved structures.
The intraocular muscles include the ciliary muscle, the sphincter pupillae, and the dilator pupillae. The ciliary muscle is a smooth muscle ring that controls accommodation by altering the shape of the lens, as well as controlling the flow of aqueous humor into Schlemm's canal. The ciliary muscle is attached to the zonular fibers which suspend the lens. Upon contraction of the ciliary muscle, the tension on the lens is lessened which causes it to adopt a more spherical shape to focus on near objects. Relaxation of the ciliary muscle has the opposite effect, optimising distant focus. The sphincter pupillae and dilator pupillae are also composed of smooth muscle. The sphincter pupillae encircles the pupil and is responsible for the constriction of its diameter, while the dilator muscle is arranged radially and increases the pupillary diameter.
There are three primary axes of ocular movements: vertical, transverse, and anteroposterior. Rotation around the vertical axis results in either adduction (medial movement) or abduction (lateral movement) of the eye. Rotation around the transverse axis causes elevation (superior motion) or depression (inferior motion). The anteroposterior axis enables movement of the superior pole of

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Retrieved Text: This is Richard Allen at the University of Iowa. This video demonstrates placement of a gold weight. The patient has a history of a right 7th nerve palsy. A 15 blade is used to make an incision along the eyelid crease through the skin and orbicularis muscle. Hemostasis is obtained with the bipolar cautery. A thermal cautery is then used to dissect between the pretarsal orbicularis muscle and the anterior surface of the tarsus in order to create a pocket for the gold weight. The weight should be placed somewhat medial. A mistake I see is placing the weight too lateral. A 6-0 prolene suture is then placed partial thickness through the anterior surface of the tarsus to engage each of the holes of the weight. The upper portion of the weight should rest at the superior border of the tarsus. The weight appears to be in good position. The eyelid is then everted to inspect the posterior surface of the tarsus to make sure none of the sutures were placed full thickness. A double layer closure is then performed over the gold weight. Orbicularis muscle is closed with interrupted 7-0 vicryl suture. This double layer closure is performed to prevent exposure of the weight. The skin is then closed with a running 6-0 prolene suture. Antibiotic ointment is placed over the incision and the patient returns in one week for suture removal.

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Retrieved Text: The process of swallowing is known as deglutition. The act of swallowing can be divided into three stages for easy understanding.
These muscles of mastication are supplied by the mandibular division of the trigeminal nerve. The tongue plays a vital role in this phase and is supplied by the hypoglossal nerve. The facial nerve also plays a vital role by supplying the Buccinator and orbicularis oris. These muscles prevent drooling of food from the mouth and keeps the contents inside the oral cavity by their contraction. In patients with facial palsy the buccinator and orbicularis oris are paralyzed causing drooling on that side of the mouth.
2. Pharyngeal stage: Is involuntary and is very complex. It passes the masticated food through the oropharynx, through the cricopharynx into the upper oesophagus. This passage is facilitated by relaxation of cricopharyngeus muscle.
During this phase the nasopharynx is shut off from the oropharynx by the contraction of muscles of soft palate and posterior pharyngeal wall, thus preventing nasal regurgitation of masticated food. During this phase the laryngeal musculature should also constrict to prevent aspiration. This stage relies on the coordination of many muscle groups including the muscles of the soft palate which is supplied by the 5th, 7th, 9th and 12th cranial nerves.
The pharyngeal muscles also play a vital role in propelling the food through the cricopharynx. These muscles are supplied by the 9th and 10th cranial nerves. The cricopharyngeus muscle is supplied by the 10th cranial nerve and sympathetic nerves.
Neurological disorders affecting the pharynx impair swallowing by altering motor and /

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Retrieved Text: FACT: 1. According to worldwide studies, 90% of people aged 20 – 65 have had at least one kiss. That doesn’t mean it was a loved one, that does include a kiss on the lips by a parent.
FACT: Kissing can increase your life expectancy by up to 5 years! Plus as an added bonus it will increase elasticity in the face making you look even younger.
FACT: The world record for longest kiss is held by Americans Rich Langley and Louisa Almedovar who for charity had a kissing session that lasted 30 hours and 59 minutes! They were allowed 5 mins every hour for a drink and something to eat.
FACT: Kissing the Blarney Stone located in Cork, Ireland is considered good luck, but legend has it that if you are untrue to your loved one you will die trying! But there is some truth to is as it is no easy feat, someone holds your feet, then you lean backwards, hold on to the handrails, and lower yourself until you can reach the stone and kiss it!
FACT: Kissing for one-minute burns 26 calories, but passionately kissing someone for the same amount of time can burn an incredible 74 calories!
4 –”Does this kiss make us cherry chums?!?
FACT: Kissing uses only one muscle, called the orbicularis oris that is responsible for puckering your lips when you go in for the kiss. The science of this act of kissing itself is called philematology.
FACT: Be careful where you kiss because in 16 countries around the world it is still illegal to

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Rank: 26
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Retrieved Text: Present Illness: This is a 51 year old Asian female presenting to the Neurology Clinic of the Ben Taub General Hospital with complaints of double vision, difficulty swallowing, and altered sensation on the left side of the face. These problems have been progressive over the last several months, and are accompanied by a dull, left-sided headache. More recently, the patient has developed hoarseness, together with some difficulty swallowing solid foods. She denies fever, chills, neck stiffness, nausea or vomiting.
Past Medical History: No other acute or chronic medical problems noted.
Past Surgical History: She underwent left parotidectomy in six years ago for unknown reasons. She has also had a cholecystectomy and a bilateral tubal ligation, remote to the present illness.
Social History: No history of alcohol, tobacco, or illicit drug use.
Family History: No history of neurologic disease in the family.
Review of Systems: There has been no recent weight gain or loss, and the patient has not noted any rashes or other skin lesions. She denies xerostomia or xerophthalmia, recent upper respiratory illness or sinusitis, or dyspnea.
General: Middle-aged Asian female in no apparent distress.
Vital Signs: Blood pressure 134/79 mm Hg; pulse 92/min, regular; respirations 14/min, temperature 98.4 F.
HEENT: Normocephalic; no evidence of trauma; conjunctivae are clear; oropharynx is clear; neck is supple without meningismus or lymphadenopathy.
Cardiovascular: Regular heart rate and rhythm with no murmurs, rubs, or gallops. Normal peripheral pulses.
Abdomen: Soft, nontender, nondistended, with (+) bowel sounds. No organomegaly.
Extremities: No cyanosis, clubbing, or edema. No rashes noted.
Mental Status: Awake, alert and fully oriented.
Speech: Fluent with intact repetition and comprehension. No

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Retrieved Text: Skeletal muscle forms the muscle's attached to the skeleton, which move the limbs and other body parts. Its cells are long, striated, and multinucleate. Skeletal muscle fibers are subject to voluntary control. Connective tissue coverings (endomysium, perimysium, and epimysium) enclose and protect the muscle fibers and increase the strength of skeletal muscles. Skeletal muscles make up the muscular system (Figure 6.1).
Smooth muscle cells are uninucleate, spindle-shaped, and arranged in opposing layers in the walls of hollow organs. When they contract, substances (food, urine, a baby) are moved along internal pathways. Smooth muscle control is involuntary (Figure 6.2).
Cardiac muscle cells are striated, branching cells that fit closely together and are arranged in spiral bundles in the heart. Their contraction pumps blood through the blood vessels. Control is involuntary (Figure 6.3).
The sole function of muscle tissue is to contract or shorten. As it contracts, it causes movement, maintains posture, stabilizes joints, and generates heat.
The multinucleate cylindrical skeletal muscle fibers are packed with unique organelles called myofibrils (Figure 6.4). The banding pattern (striations) of the myofibrils and the cell as a whole reflects the regular arrangement of thin (actin-containing) and thick (myosin) filaments within the sarcomeres, the contractile units composing the myofibrils (Figure 6.5).
Each myofibril is loosely enclosed by a specialized ER, called the sarcoplasmic reticulum (SR), which plays an important role in storing and releasing calcium ions. Calcium ions are the final "trigger" for muscle fiber contraction.
All skeletal muscle cells are stimulated by motor neurons. When the neuron releases a neurotransmitter (acetylcholine), the permeability of the sarcolemma changes,

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Score: 54.914757
Retrieved Text: There is a weak relationship between severity of pain and degree of oxygen deprivation in the heart muscle (i.e., there can be severe pain with little or no risk of a myocardial infarction (heart attack) and a heart attack can occur without pain). In some cases, angina can be quite severe, and in the early 20th century this was a known sign of impending death. However, given current medical therapies, the outlook has improved substantially. People with an average age of 62 years, who have moderate to severe degrees of angina (grading by classes II, III, and IV) have a 5-year survival rate of approximately 92%.Worsening angina attacks, sudden-onset angina at rest, and angina lasting more than 15 minutes are symptoms of unstable angina (usually grouped with similar conditions as the acute coronary syndrome). As these may precede a heart attack, they require urgent medical attention and are, in general, treated in similar fashion to myocardial infarction.
Bronchospasms are one of several conditions associated with cold housing.Some of the things that can cause bronchospasms are: consuming foods, taking medicines, allergic responses to insects, and fluctuating hormone levels, particularly in women.A few of the more common allergens are foods such as eggs, milk, peanuts, walnuts, tree and other nuts, fish, especially shellfish, soy and wheat; insect bites and stings, especially bee stings; and other medicines, especially penicillin and its derivatives.
Cadaveric spasm, also known as postmortem spasm, instantaneous rigor, cataleptic rigidity, or instantaneous rigidity, is a rare form of muscular stiffening that occurs at the moment of death and

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Rank: 29
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Retrieved Text: There’s been a pivotal shift in how women in their 20s look at their faces. And while the reasons are arguably as multi-faceted as this new generation itself, many would agree on one thing: The impact of social media, from selfies to YouTube videos to meticulously crafted Snapchat and Insta Stories, combined with endlessly retouched photographs in magazines and ad campaigns, can not be underestimated. From the constant stream of supernaturally smooth jawlines and chiseled cheekbones to celebrity plastic surgeons posting before-and-after images of their work, the age of 24/7 self-documentation has spurred a novel set of beauty ideals—and, with it, a dramatic increase in cosmetic procedures. For 20-somethings, there’s no treatment more popular—or controversial—than Botox. According to the American Society of Plastic Surgeons, botulinum toxin procedures have increased 28 percent since 2010 amongst 20 to 29-year-olds.
Most doctors suggest focusing on the quality of the skin with a proper regimen that includes daily exfoliation and SPF protection, as well regular chemical peels or specialized treatments such as Clear and Brilliant laser resurfacing during this decade. Still, there are exceptions. As any good dermatologist will note, there is a caveat: When it comes to Botox and filler, there’s a fine line between targeted tweaks and doing too much too soon. Here, in-demand experts share their guidelines for women in their 20s.
When women in their 20’s first consider getting Botox, prevention is often the primary factor, since the early signs of aging—such as crow’s feet, forehead wrinkles, and fine lines—are beginning to show. “Lines get deeper and deeper

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======= Instance Index 2998 =========
Input Text: Answer the following question given this paragraph: 

CHAPTER REVIEW 20.1 Structure and Function of Blood Vessels Blood pumped by the heart flows through a series of vessels known as arteries, arterioles, capillaries, venules, and veins before returning to the heart. Arteries transport blood away from the heart and branch into smaller vessels, forming arterioles. Arterioles distribute blood to capillary beds, the sites of exchange with the body tissues. Capillaries lead back to small vessels known as venules that flow into the larger veins and eventually back to the heart. The arterial system is a relatively high-pressure system, so arteries have thick walls that appear round in cross section. The venous system is a lower-pressure system, containing veins that have larger lumens and thinner walls. They often appear flattened. Arteries, arterioles, venules, and veins are composed of three tunics known as the tunica intima, tunica media, and tunica externa. Capillaries have only a tunica intima layer. The tunica intima is a thin layer composed of a simple squamous epithelium known as endothelium and a small amount of connective tissue. The tunica media is a thicker area composed of variable amounts of smooth muscle and connective tissue. It is the thickest layer in all but the largest arteries. The tunica externa is primarily a layer of connective tissue, although in veins, it also contains some smooth muscle. Blood flow through vessels can be dramatically influenced by vasoconstriction and vasodilation in their walls.


Q: Blood vessels blood pumped by the heart flows through a series of vessels known as arteries, arterioles, capillaries, venules, and veins before returning to this?

 Choices:

- brain

- lungs

- feet

- heart

A:

Target Text: heart

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Retrieved Text: Blood vessel is an elastic tube or passage in the body through which blood circulates; an artery, a vein, or a capillary. There are three major types of blood vessels: the arteries, which carry the blood away from the heart; the capillaries, which enable the actual exchange of water and chemicals between the blood and the tissues; and the veins, which carry blood from the capillaries back toward the heart.
Blood vessels are constructed of layers of connective tissue and muscle. The inner blood vessel layer is formed of endothelium. In capillaries and sinusoids, endothelium comprises the majority of the vessel. Blood vessel endothelium is continuous with the inner tissue lining of organs such as the brain, lungs, skin, and heart. In the heart, this inner layer is called the endocardium.
Blood is circulated through the body via the cardiovascular system. This system is comprised of the heart and the circulatory system. Blood vessels carry blood from the heart to all areas of the body. Blood travels from the heart via arteries to smaller arterioles, then to capillaries or sinusoids, then to venules, to veins, and back to the heart.
Arteries carry blood away from the heart. Pulmonary arteries transport blood that has a low oxygen content from the right ventricle to the lungs. Systemic arteries transport oxygenated blood from the left ventricle to the body tissues. Blood is pumped from the ventricles into large elastic arteries that branch repeatedly into smaller and smaller arteries until the branching results in microscopic arteries called arterioles. The arterioles play a key

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Retrieved Text: The cardiovascular system includes the heart (cardio) and blood vessels (vascular). The heart pumps blood throughout the body. Sixty thousand miles of blood vessels transport the blood, enough to encircle Earth more than twice. Arteries carry blood away from the heart; capillaries reach all of the body's seventy trillion cells; and veins carry blood back to the heart. Because blood vessels form a circular route, this system is also called the circulatory system.
The cardiovascular system has two main parts. In the pulmonary circuit, blood is pumped from the right ventricle of the heart through the pulmonary arteries, which lead to the lungs. Here the blood gives up carbon dioxide and picks up oxygen. The oxygen-rich blood returns to the left atrium of the heart through pulmonary veins. From the left atrium, blood passes to the left ventricle of the heart, which pushes the blood through the systemic circuit beginning with the aorta, which branches to all body parts.
A scanning electron micrograph of red and white blood cells flowing through a vein.
After delivering oxygen and picking up carbon dioxide, blood returns to the right atrium of the heart and then to the right ventricle. The journey begins anew.
Thick walls enable arteries to withstand the pressure created by the pumping of the heart (blood pressure). The pulmonary arteries and the aorta are the largest arteries (the aorta is as wide as a thumb!). Some arteries are named for the organ that they supply, such as the hepatic artery (liver) and the coronary arteries (heart). Others have special names,

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Retrieved Text: In order for the body to stay alive, each of its cells must receive a continuous supply of food and oxygen. At the same time, carbon dioxide (CO2) and other materials produced by the cells must be picked up for removal from the body. This process is continually maintained by the body's circulatory system. The primary circulatory system consists of the heart and blood vessels, which together maintain a continuous flow of blood through the body delivering oxygen (O2) and nutrients to and removing CO2 and waste products from peripheral tissues. A subsystem of the circulatory system, the lymphatic system, collects interstitial fluid and returns it to the blood. The heart pumps oxygen-rich blood from the lungs to all parts of the body through a network of arteries, and smaller branches called arterioles. Blood returns to the heart via small venules, which lead to the larger veins. Arterioles and venules are linked even to even smaller vessels called metarterioles. Capillaries, blood vessels a single cell thick, branch off from the metarterioles and then rejoin them. The network of tiny capillaries is where the exchange of O2 and CO2 between blood and body cells takes place. The average adult has over 60,000 miles of blood vessels in their body.

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Retrieved Text: A blood vessel is any of the tubular channels that convey blood throughout the body, whether arteries (including threadlike arterioles) that convey blood away from the heart, veins (including threadlike venules) that convey blood toward the heart, or the tiny capillaries that connect arterioles and venules. Exchange of water, gases, and chemicals between the blood and the tissues occurs through the thin walls of the capillaries.
Blood vessels in humans range in diameter from only eight μm (.008 mm) for the capillaries to 25,000 μm (25 millimeters, or one inch) for the aorta (Blakemore and Jennett 2001).
In vertebrates, blood vessels are part of a complex circulatory system centered on the heart. The warm-blooded vertebrates (mammals and birds) have the most complex circulatory systems involving diverse vessel tissues and wall thicknesses, regulation of blood pressure, interactions with nerves and hormones, and so forth.
The three principal categories of blood vessels are arteries, veins, and capillaries. Arteries are muscular blood vessels that carry blood away from the heart to the cells, tissues, and organs of the body. Veins carry blood toward the heart. They are are less muscular than arteries, and most of them have one-way valves that prevent backflow. The arteries subdivide into smaller arteries, which give rise to smaller, threadlike blood vessels called arterioles, which are the smallest of the true arteries. Likewise, venules are small, threadlike veins. Capillaries, the smallest of a body's blood vessels, connect arterioles and venules.
The arteries are perceived as carrying oxygenated blood to the tissues, while veins carry deoxygenated blood back to the

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Retrieved Text: Capillary vessels are very fine structures. Their walls are made of one layer of cells and a basal membrane. This is where nutrient and waste exchanges between tissues and blood take place. In humans there are about 10 billion capillaries with an exchange surface area of between 500 and 700 m2. Thus anywhere in the body it is rare for a cell to be more than 20 or 30 micrometers far from a capillary.
Generally nutrient arteries divide 6 to 8 times on entering the organs until the diameter becomes small enough for branches to be called arterioles (under 20^m in diameter). The arterioles then divide 2 to 5 times, decreasing to diameters of between 5 and 9 ^m, where they end by transferring blood to the capillaries.
The basic structure of microcirculation is the microcirculatory unit where blood enters the capillary network from an arteriole and leaves by a venule. Blood from the arteriole flows through a series of metarterioles (also called terminal arterioles) whose structure is halfway between that of arterioles and that of capillaries. After leaving the metarterioles, blood enters the capillary network which is made of some wide capillary vessels (called preferential channels) and other smaller ones that are called real capillaries. When blood leaves the capillary network it flows into the venules and returns to the general blood flow.
In their walls, arterioles have a thick muscle layer and thus they can undergo extensive changes in diameter. Metarterioles (terminal arterioles) have no continuous muscle layer but smooth muscle fibres surrounding the vessel at certain

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Retrieved Text: Blood flow through the capillary beds is regulated depending on the body’s needs and is directed by nerve and hormone signals. For example, after a large meal, most of the blood is diverted to the stomach by vasodilation of vessels of the digestive system and vasoconstriction of other vessels. During exercise, blood is diverted to the skeletal muscles through vasodilation while blood to the digestive system would be lessened through vasoconstriction. The blood entering some capillary beds is controlled by small muscles, called precapillary sphincters, illustrated in (Figure). If the sphincters are open, the blood will flow into the associated branches of the capillary blood. If all of the sphincters are closed, then the blood will flow directly from the arteriole to the venule through the thoroughfare channel (see (Figure)). These muscles allow the body to precisely control when capillary beds receive blood flow. At any given moment only about 5–10% of our capillary beds actually have blood flowing through them.
See the circulatory system’s blood flow.
Proteins and other large solutes cannot leave the capillaries. The loss of the watery plasma creates a hyperosmotic solution within the capillaries, especially near the venules. This causes about 85% of the plasma that leaves the capillaries to eventually diffuse back into the capillaries near the venules. The remaining 15% of blood plasma drains out from the interstitial fluid into nearby lymphatic vessels ((Figure)). The fluid in the lymph is similar in composition to the interstitial fluid. The lymph fluid passes through lymph nodes before it returns to the heart via

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Retrieved Text: This is the largest of all blood vessels and transports blood away from the left ventricle of the heart where it then branches into smaller arteries. As the arteries divide further they become smaller and smaller, until they are classed as arterioles. Arterioles continue to branch into smaller and smaller vessels which, once they have decreased in size below 10 micrometers in diameter are known as capillaries.
The pulmonary artery is classed as an artery as it carries blood away from the heart, however, it carries deoxygenated blood. The blood it carries has travelled around the body and back to the heart where it is pumped, via the pulmonary artery, to the lungs to release waste products and pick up more oxygen.
Tunica Media: This is the middle layer and consists of smooth muscle and elastic fibres. This layer is thicker in arteries than veins.
Tunica Intima: This is the inner layer which is in direct contact with the blood flowing through the artery. It consists of an elastic membrane and smooth endothelial cells. The hollow centre through which blood flows is called the lumen.
Smaller arteries and arterioles contain more smooth muscle tissue in order to control the changing pressure of the blood flow. This change in pressure is a direct effect of the pumping of the heart. During the diastolic phase blood pressure is low due to the rest period of the heart. In the systolic phase the heart contracts, forcing blood through the arteries and subsequently increasing the pressure. This change in pressure within an artery is

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Rank: 7
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Retrieved Text: In general, there are three primary components of the coronary system. The first is the coronary arteries; this important group of vessels originates with the right and left main coronary arteries, which exit the ascending aorta just above the aortic valve. The smallest of the arteries eventually branch into arterioles. In turn, the arterioles branch into an extremely large number of capillaries, the smallest diameter vessels, which make up the second vessel system. Next, blood exits the capillaries and begins its return to the heart via the venules through the third component system of vessels, the venous drainage of the heart. Thus, the coronary veins drain the deoxy-genated blood from the myocardium back to the right atrium, in which it joins with the systemic deoxygenated blood entering from the superior and inferior venae cavae.
quite detrimental and/or often deadly. For example, changes in electrocardiograms can be recorded within beats when there is inadequate blood flow delivered to a region of the heart. More specifically, whenever coronary blood flow falls below that required to meet metabolic needs, the myocardium is considered ischemic; the pumping capability of the heart is impaired. and there are associated changes in electrical activity (e.g., increased risk of fibrillation). Prolonged ischemia can lead to myocardial infarction, commonly called a heart attack. This can cause permanent, irreversible myocardial cell death. Coronary artery disease remains the most common and lethal cardiovascular disease in the US population affecting both males and females (1).

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Retrieved Text: Search for Where Are Capillaries. Direct CBSi results here!
Tired of Endless Searching? Find Where Are Capillaries on DealsNow.
A capillary is an extremely small blood vessel located within the tissues of the body that transports blood from arteries to veins.Capillaries are most abundant in tissues and organs that are metabolically active. For example, muscle tissues and the kidneys have a greater amount of capillary networks than do connective tissues.
The glomerulus is a tuft of small blood vessels called capillaries located within Bowman's capsule within the kidney. Glomerular mesangial cells structurally support the tufts. Blood enters the capillaries of the glomerulus by a single arteriole called an afferent arteriole and leaves by an efferent arteriole.
Location: The coronary system is comprised of arteries, arterioles, capillaries, venules and veins. The coronary arteries originate as the right and left main coronary arteries which exit the ascending aorta just above the aortic valve (coronary ostia).
Capillaries are the smallest of blood vessels. Their walls consist of a single layer of endothelial cells and the smallest have a single endothelial cell wrapped around to join with itself. These permit a single red blood cell to pass through them but only by deforming itself.
The arterial blood system branches extensively to deliver blood to over a billion capillaries in the body. The extensiveness of these branches is much more readily appreciated by knowing that the capillaries provide a total surface area of 1,000 square miles for exchanges of gases, waste, and nutrients between blood and tissue fluid.
Capillaries Capillaries are extremely small vessels located within the tissues

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Retrieved Text: Larger arteries have less smooth muscle per volume when compared to smaller arteries (also called arterioles). What would you expect as a result of this distinction?
Capillaries will have an even larger amount of smooth muscle per volume, because they are even smaller than arterioles.
The smooth muscle is responsible for keeping the arterioles constricted at all times.
Arterioles are able to regulate blood pressure more efficiently than large arteries.
Smaller arteries have more muscle tone, and are able to tolerate more pressure than large arteries.
Smooth muscle is typically innervated by the sympathetic nervous system. Because arterioles have more smooth muscle per volume, they are able to respond to sympathetic innervation more efficiently than larger arteries. As a result, the smaller arteries are used to regulate blood pressure as well as reroute blood direction by adjusting arteriole diameter accordingly.
Bundle of His is also known as the AV bundle.
The SA Node is located in upper right atrium. It initiates the depolarization impulse, which, in turn, generates an action potential that spreads via the internodal pathway situated in the walls of the atria to the AV node. From there, the impulse travels to the Bundle of His, then to the bundle branches and finally to the purkinje fibers.
Which of the following vessels transports blood from the lungs to the heart?
Veins carry blood to the heart, while arteries carry blood away from the heart. The pulmonary veins are the only veins in the body that carry oxygenated blood. It is important to remember not to confuse these veins with the pulmonary arteries, which

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Retrieved Text: "Vascular" redirects here. For information about plants, see Vascular plant.
The inner layer, tunica intima, is the thinnest layer. It is a single layer of flat cells (simple squamous epithelium) glued by a polysaccharide intercellular matrix, surrounded by a thin layer of subendothelial connective tissue interlaced with a number of circularly arranged elastic bands called the internal elastic lamina. A thin membrane of elastic fibers in the tunica intima run parallel to the vessel.
The middle layer tunica media is the thickest layer in arteries. It consists of circularly arranged elastic fiber, connective tissue, polysaccharide substances, the second and third layer are separated by another thick elastic band called external elastic lamina. The tunica media may (especially in arteries) be rich in vascular smooth muscle, which controls the caliber of the vessel. Veins don't have the external elastic lamina, but only an internal one. The tunica media is thicker in the arteries rather than the veins.
The outer layer is the tunica adventitia and the thickest layer in veins. It is entirely made of connective tissue. It also contains nerves that supply the vessel as well as nutrient capillaries (vasa vasorum) in the larger blood vessels.
When blood vessels connect to form a region of diffuse vascular supply it is called an anastomosis. Anastomoses provide critical alternative routes for blood to flow in case of blockages.
There is a layer of muscle surrounding the arteries and the veins which help contract and expand the vessels. This creates enough pressure for blood to be pumped around the body. Blood vessels are part

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Retrieved Text: The flow of blood or lymph through the smallest vessels of the body, as the venules, capillaries, and arterioles.
"microcirculation." YourDictionary, n.d. Web. 16 April 2019. <https://www.yourdictionary.com/microcirculation>.

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Retrieved Text: /car·dio·vas·cu·lar/ (-vas´ku-ler) pertaining to the heart and blood vessels.
Of, relating to, or involving the heart and the blood vessels: cardiovascular disease.
Referring to the circulatory system, which consists of the heart and the pulmonary and systemic circulation, which transport nutrients and oxygen to and remove waste products and carbon dioxide from organs and tissues.
Relating to the heart and the blood vessels or circulation.
Relating to the heart and its connected closed circulatory system of blood vessels (arteries, arterioles, capillaries, venules and veins).
Relating to heart and blood vessels or circulation.
Neural pathways regulating food intake, body weight, and the cardiovascular system may be particularly vulnerable to the metabolic status of the obese or diabetic mother.
The trial is a randomized, placebo-controlled, double-blind, dose ranging study to evaluate the impact of MC-1 and determine its protective effect on combined cardiovascular and neurological events after CABG surgery.
Combined with previous studies by the Taiwanese team, the new research "clearly shows there is a cardiovascular risk associated with drinking arsenic-laden water," says Barchowsky.
The life expectancy of blacks is lower than that of whites nationwide, and cardiovascular disease is a main reason, they said.
The animals provide a good model to test cardiovascular effects of menopause because "they rapidly develop cardiovascular disease after surgery while on a high-fat diet," says veterinarian Michael R.
Use this report to identify the leading cardiovascular companies to 2011 and discover the cardiovascular blockbusters of the future.
These joint research and development efforts are critical steps toward bringing forth important new detection and treatments to patients at high risk for cardiovascular disease.
Leman Cardiovascular, a

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Retrieved Text: 3. What does the heart look like inside?
5. Why does the heart have two atria and two ventricles?
Inhaled air contains oxygen that enters our lungs. We breathe in air with 21 % oxygen and 0.03 % carbon dioxide. We breathe out 16 % oxygen and 4 % carbon dioxide. Below the lungs works a large muscle called the diaphragm. When the muscle tenses (contracts), it pulls the lower part of the chest cavity downward. The lower parts of the lungs are pulled along as well. The chest cavity is enlarged and the lungs as well. Air is flowing into the lungs. The diaphragm is shown in red.
Left image: Inhalation. Active process - the muscle is contracting.
Right image: Exhalation. Passive process – the muscle is relaxing – is stretched.
The trachea divides into two bronchi (air pipes). One bronchus connects to each lung. The bronchus divides itself and at the end of each branch is an alveolus. The oxygen-poor (deoxygenated) blood from the heart (shown blue - dark red in reality) absorbs oxygen from the air. This makes the blood oxygen-rich (oxygenated: shown red - light red in reality). Carbon dioxide from the blood enters the alveolus cavity and is exhaled.
The oxygen migrates into the bloodstream from the alveoli because the oxygen pressure is higher in the air and lower in the blood. This pressure difference evens out automatically the best it can. The same principle applies to carbon dioxide, but the pressure difference is the opposite.
Small cells in the blood called red blood cells absorb the oxygen.

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Retrieved Text: The cardiovascular system includes the heart, blood, and blood vessels (arteries, veins and capillaries).
Our blood circulates through this network of vessels throughout the whole organism. By this it can provide individual cells with oxygen and nutrients.
As the heart is powering a circulatory system, its pumping action also causes blood to return to the heart.
During this part of the journey, blood collects waste products, which are eliminated in the lungs. The lungs refresh the blood with oxygen and nutrients before it is returned to the heart to start the circulation process once again.
We have learned that our blood travels through the bloodstream - a system of blood vessels, or tubes, of varying sizes, which reach all parts of the organism. The tubes that carry blood away from our heart are called arteries, which carry blood pumped under high pressure to smaller and smaller branched tubes, called capillaries. Blood always leaves the heart through arteries, which include the aorta and pulmonary arteries. Conversely, blood enters the heart through the veins, the largest being the pulmonary veins and the vena cava.
Various control mechanisms help to regulate and integrate the miscellaneous functions and component parts of the cardiovascular system in order to supply blood to specific body areas according to need. These mechanisms ensure a perpetual internal environment surrounding each body cell regardless of differing demands for nutrients or production of waste products.

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Retrieved Text: Veins are elastic tubes, or blood vessels, that carry blood from your organs and tissues of the body back to your heart.
Veins are different from arteries. But together veins and arteries form an important network to transport blood throughout the body.
Most veins carry blood that is low in oxygen back to the heart. Contrary to popular belief, blood that is low in oxygen is not blue in color, but rather it is dark red. Veins only appear blue when seen through the skin.
After the oxygen and nutrients have been delivered to the body’s tissues by the arteries and capillaries, a second network of venules and veins carries blood and waste products back to the heart.
Smaller tubes, venules, pick up the oxygen-depleted blood and transfer it to the veins, which carry it back to the heart. Once the veins return blood to the heart, it is pumped to the lungs. Here, the carbon dioxide from the venous blood is expelled as we breathe out. The oxygen we breathe in is picked up by the blood flowing through the lungs. This blood that is replenished with oxygen returns to the heart where it is pumped back into the rest of the body and the process starts again.
The veins throughout the body support many systems and are critical to your cardiovascular health and many other functions of blood, including waste removal.
Varicose veins and spider veins (caused by venous insufficiency, or faulty valves in the veins) are among the most common vein conditions. They usually affect the veins in your

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Retrieved Text: In the body oxygen is transported through the blood vessels. Oxygen-rich blood from the lungs is circulated by the heart to the brain and the rest of the body by large arteries. These arteries split and get smaller. At the place of destination (in the body) there should be a transfer taking the place of oxygen and nutrients. The blood flow may, of course, not be too fast, otherwise this transfer does not take place. Because the arteries so frequently have split and ever have narrowed blood eventually flows very slowly. The small vessels where this transfer of oxygen and nutrients takes place are the capillaries (capillaries). Eventually it becomes oxygen-poor blood again collected in small vessels which come back together and get bigger; the veins. The veins transport the oxygen-poor blood back to the heart.
A capillary malformation is a departure from the capillaries. These vessels are then usually widened, making you the typical color of this skin condition. A capillary malformation is a slow-flow vascular malformation. Examples include the Wine Stain (Nevus flammeus), Stork bite and Cutis Marmorata Telangiectatica Congenita (CMTC).

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Retrieved Text: The lungs have both a bronchial and a pulmonary circulation. The bronchial circulation to the lungs is the part of the systemic circulation that supplies O2 and nutrients to meet the metabolic requirements of the lungs.
However the pulmonary circulation refers to the portion of the cardiovascular system which carries deoxygenated blood away from the heart, towards the alveoli of the lungs to undergo gas exchange, and then returns oxygenated blood back to the heart.
In this article we shall consider the functions of both the bronchial and the pulmonary circulation and the special adaptations required to meet these.
Deoxygenated blood leaves the right ventricle of the heart through the pulmonary valve and enters the pulmonary trunk. This divides into the right and left pulmonary arteries.
In the lungs the arteries divide further into very fine capillaries at the alveoli, allowing gas exchange to take place. Oxygen diffuses from the alveoli into the pulmonary capillaries while carbon dioxide diffuses from the capillaries into the alveoli.
This newly oxygenated blood leaves the lungs through the pulmonary veins to the left atrium of the heart, completing the pulmonary cycle. The blood is then distributed around the body via the systemic circulation.
Since the right heart cannot work independently of the left heart both the right and left ventricle must have the same cardiac output to prevent blood building up in either the systemic or pulmonary circulation. This means the pulmonary circulation must be able to accept the entire cardiac output (5L).
Low resistance – short, wide pulmonary vessels, many capillaries running in parallel, rather than

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Retrieved Text: The major vessels of the coronary circulation are the left main coronary that divides into left anterior descending andcircumflex branches, and the right main coronary artery. The left and right coronary arteries originate at the base of the aorta from openings called the coronary ostia located behind the aortic valve leaflets.
The left and right coronary arteries and their branches lie on the surface of the heart, and therefore are sometimes referred to as the epicardial coronary vessels. These vessels distribute blood flow to different regions of the heart muscle. When the vessels are not diseased, they have a low vascular resistance relative to their more distal and smaller branches that comprise the microvascular network. As in all vascular beds, it is the small arteries and arterioles in the microcirculation that are the primary sites of vascular resistance, and therefore the primary site for regulation of blood flow. The arterioles branch into numerous capillaries that lie adjacent to the cardiac myocytes. A high capillary-to-cardiomyocyte ratio and short diffusion distances ensure adequate oxygen delivery to the myocytes and removal of metabolic waste products from the cells (e.g., CO2 and H+). Capillary blood flow enters venules that join together to form cardiac veins that drain into the coronary sinus located on the posterior side of the heart, which drains into the right atrium. There are also anterior cardiac veins and thesbesian veins drain directly into the cardiac chambers.
Although there is considerable heterogeneity among people, the following table indicates the regions of the heart that are generally supplied by the

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Retrieved Text: The circulatory system offers the vessels along with the muscles that allow and control the flow in the blood around your system. This process is considered circulation. The main portions of the system are definitely the heart, arteries, capillary vessels and veins.
The Circulatory System strengthens transporting materials in the entire body. The idea transports nutrients, mineral water, and oxygen for a billions of cells and carries away wastes which include carbon dioxide that cells produce. It can be an amazing highway that will travels through your own whole body connecting every one of your body cells.
On a daily basis, the approximately 10 pints (5 liters) of blood in the male body travel many circumstances through about sixty, 000 miles (96, 560 kilometers) of as well as that branch together with cross, linking the cells in our organs and areas of the body. From the hard-working cardiovascular system, to our thickest blood vessels, to capillaries so thin that they only be seen via the microscope, the heart is our body lifeline.
Our bodies already have two circulatory solutions: The pulmonary circulation can be a short loop in the heart to that lungs and to return, and the systemic move (the system we usually see as our circulatory system) sends blood in the heart to the rest of the parts of people and back ever again.
Additional blood gets pumps the blood in the body. It sits contained in the chest, in front in the lungs and slightly left side. The heart is a double pump consisting of four chambers.

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Retrieved Text: Pulmonary arterial hypertension is a type of blood pressure that affects the arteries of the lungs and right side of the heart. It begins when the small pulmonary arteries (lungs arteries) and capillaries become blocked, narrowed or destroyed. This makes the heart difficult to flow the blood through the lungs, thus increase the blood pressure within the arteries in lungs. In this way, when the pressure increases, the ventricles (lower chamber of heart) of the heart must work harder to keep the blood flow intact through the lungs. If the heart works like this for a long time the muscles of heart become weak and eventually fail completely.
The heart has four chambers, two upper and two lower chambers. Every time blood passes through the heart, the lower right chambers passes the blood through the pulmonary artery which is one of the large blood vessel of the heart connects the heart with lungs. In the lungs, the blood takes oxygen and releases carbon-di-oxide and supply the oxygen rich blood to the left side of the heart through the pulmonary arteries, capillaries and veins. Normally, the blood pressure is much lower in lungs because the blood flows very easily through the vessels of the lungs. Pulmonary hypertension occurs – when the blood vessels supplying blood to the lungs become altered and induce extra cells to grow in the blood vessel lining. This makes the vessel narrower which eventually blocks and stiffens the arteries. In this way, blood pressure raises and makes the heart difficult to pump the blood

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Retrieved Text: Paul Monach, M.D. Boston University explains how cryoglobulinemia affects the blood vessels. Cryoglobulinemia is rare, not well known and can cause serious health issues for those living with the disease.
Cryoglobulinemia is a disease defined by the presence of cryoglobulins; which are proteins (also called immunoglobulins or antibodies) that become thick in cold temperatures. This process can restrict blood flow causing damage (vasculitis) to skin, joints, muscles, nerves and/or organs. Cryoglobulins are antibodies. Cryoglobulinemia, in the vast majority of patients, occurs due to Hepatitis C (HCV). Approximately 90 percent of people with cryo have it due to HCV. Cryoglobulinemia is part of a group of diseases called vasculitis — damage and inflammation of the blood vessels throughout the body. Vasculitis is an inflammation of the blood vessels (vascular = blood vessels, itis = inflammation). Vasculitis can occur as the main disease or as a complication of another disease. Vasculitis may happen as the result of an infection, a medicine, or another disease or condition.
Vasculitis can affect any blood vessel: arteries, veins, and capillaries. Arteries deliver blood from the heart to organs. Veins return blood back to the heart. Capillaries are tiny blood vessels that connect small arteries and veins. When a blood vessel becomes inflamed the vessel can narrow, making it more difficult for blood to get through, close off completely so that blood cannot pass through, stretch and weaken the wall of the vessel causing collapse or necrosis.

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Retrieved Text: Kidneys are one of the vital organs of our body. These are available in pairs and if one of it is not functioning properly, the other one can take care of it. The Kidneys filter the waste and act as disposal system of the body. Approximately 1/3 of all blood exiting the heart flows into the kidneys for filtration before it flows to the rest of the body’s tissues.
Kidneys are a pair of organs located below our ribs, in the back of the abdomen. It has purplish-brown colour and is solely responsible for removing liquid waste from blood, which is later excreted in the form of urine.
What is the structure of Kidney?
The Kidneys are bean-shaped and their concave sides known as renal hilus, face each other and these are connected to the blood vessels – renal artery and renal vein, and also to the ureter that takes urine out of the Kidney. The Kidney is covered by a fibrous layer of connective tissue and the layer is called renal capsule. Under this layer is a soft inner layer of tissues known as renal cortex, which covers another layer known as renal medulla. This renal medulla is made of seven cone-shaped tissues known as renal pyramids. The bases of the renal pyramids are towards the renal cortex and the apexes are facing towards the center of the Kidney. Each of the apexes is connected to a small hollow tube known as calyx which collects urine. These small calyces join together forming 3 large calyces. These 3 calyces

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Retrieved Text: Veins are vessels designed to collect and return blood, including deoxygenated hemoglobin, from tissues to the heart. In humans, veins and the venous vascular system can be divided in to three separate systems depending on anatomical relationships and function. Initially, veins can be divided into systemic and pulmonary systems. The veins that drain the heart, comprising the coronary venous system, may be described as an independent venous system, or be considered a subset of the systemic vascular system. The systemic veins transport venous blood—deoxygenated when compared with arterial blood—from the body to the heart. The pulmonary veins return freshly oxygenated blood from the lungs to the heart so that it may be pumped into the systemic arterial system.
Veins can also be described by their anatomical position. Deep veins run in organs or connective tissue that supports organs, muscle, or bone. Superficial veins are those that drain the outer skin and fascia.
In contrast to arteries, veins often run a more convoluted course, with frequent branching and fusions with other veins (anastomoses) that make the tracing of the venous system less straightforward than mapping the arterial system. In addition, there are reservoirs or pools (sinus) that collect venous return from multiple sources. Many veins contain valves that assure a unidirectional (one way) flow of venous blood toward the heart.
The systemic venous system can be roughly divided into groups depending on the region they drain, and the vessel through which they return blood to the heart.
The first systemic venous group consists of veins that drain the head, neck, thorax,

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Retrieved Text: Lymphocytes---A form of small leucocyte(white blood cell)with a single round nucleus, occuring especially in the lymphatic system.
Phagocytes---A type of cell within the body capable of engulfing and absorbing bacteria and other small cells and particles.
White Blood Cells---White blood cells protect you from diseases. They ingest pathogens and produce antibodies.There are several types of white blood cells:Phagocytes,Lymphocytes are examples.
Valves---A device for controlling the passage of fluid or air through a pipe, duct, especially an automatic device allowing movement in one direction only.
a hollow part or cavity in an organ.
each of the four connected fluid-filled cavities in the centre of the brain.
Atria---The atrium is the upper chamber in which blood enters the heart. There are two atria in the human heart – the left atrium connected to the lungs, and the right atrium connected to the venous circulation. The atria receive blood, and when the heart muscle contracts they pump blood to the ventricles.
Capillaries---Any of the fine branching blood vessels that form a network between the arterioles and venules.
Plasma---Plasma carries dissolved nutrients hormones,urea,glucose and salts are dissolved in the plasma.
Red Blood Cells---Red Blood Cells transport the oxygen required for aerobic respiration in body cells .Carry oxygen and carbon dioxide.Haemoglobin blinds to the oxygen.They are flexible to squeeze down capillaries.
Muscles---a band or bundle of fibrous tissue in a human or animal body that has the ability to contract, producing movement in or maintaining the position of parts of the body.
Bones---any of the pieces of hard whitish tissue making up the skeleton in humans and other vertebrates.

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Retrieved Text: Contraction of blood vessels and observations on the circulation in the transparent chamber in the rabbit's ear.
the ‘Rouget’ cell, leaving a clear space between.
and that capillary contraction plays an important rale in regulating blood flow.
Society of Philadelphia, May, 1928.
2 partially contracted; D, both 1 and 2 completely contracted. x 310.
relaxation are definitely longer after the partial contraction.
. . . . . I . . . . .
same time as did the rhythmical ones of the arteries within the whole chamber.
and their subsequent adult growth.
may be quite noticeable, particularly in the larger vessels.
of the flow of the plasma containing platelets only.
which there is no circulation.
interrupted stream, a few cells with each beat of the heart.
is almost equal to that in the artery.
cell (Adv.) ; capillary (Cap.). X 412.
lumen. Such a bulging in a capillary is shown in figure 3.
average of forty per minute.
directly 011 the surface of the chamber).
circulation continued as it did previous t o the experiment.
ear to 37 C., has already been described ( Sandison, '31).
dilatation had very little eEect upon the capillary circulation.
again returned to its normal condition.
The specific reaction of the different types of vessels during these experiments may be followed in figures 4 and 5.
the artery; E, point beyond whieli coiitraetioii did iiot occur at 2 0 ”. x 206.
and of its arteriole branchings mere noted, and they coiiformed to the changes whicli hare been previously described.
normal, widened slightly with each beat of the heart.
the arteriole and the venule a slow circulation prevailed.
they had lain directly upon these muscle cells.
THE A N

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Retrieved Text: 1. The Transport System in Humans •All cells in our body need nutrients, oxygen and water. Meanwhile carbon dioxide and other waste materials produces by the cells must be removed. •An internal transport system is needed to deliver useful materials to the body cells and remove the waste materials from them. •The internal transport system is often called the circulatory system because useful as well as waste materials circulate the body.
3. •A circulatory system has four basic characteristics: a. Circulating fluid – this circulating fluid is called blood. The blood transports useful and waste materials. b. Pumping device – the pumping device is the heart. Blood is moved through the body by muscular contractions of the heart. c. Blood vessels – a complex network of blood vessels carries materials to the tissues and back to the heart. There are three main types of blood vessels, namely arteries, veins and capillaries. d. Valves – valves are present in some blood vessels to prevent backflow and ensure that blood flows in one direction only.
4. •The human circulatory system is a double circulatory system. This means that in each complete circuit of the body, the blood must flow through the heart twice. •The human double circulatory system consists of: a. The pulmonary circulation which transports blood between the heart and the lungs and a. The systematic circulation which transports blood between the heart and all other parts of the body.
6. Structure of the human heart •An adult human heart is about the size of a clenches fist. •The heart

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Retrieved Text: Lab Bio, enjoy this lecture on the circulatory and respiratory systems!
3. The circulatory system and respiratory system work together to supply cells with the nutrients and oxygen they need to stay alive.
4. Functions of the Circulatory System Humans and other vertebrates have closed circulatory systems In a closed circulatory system, blood is transported within a system of vessels.
6. The Heart The heart is enclosed in a protective sac of tissue called the pericardium. In the walls of the heart, two layers of epithelial and connective tissue form around a thick layer of muscle called the myocardium. Contractions of the myocardium, (thick layer of muscle) pump blood.
17. The septum divides the right side of the heart from the left. It prevents the mixing of oxygen-poor and oxygen-rich blood.
18. The heart has four chambers—two atria and two ventricles. There are two chambers on each side of the septum. The upper chamber, which receives the blood, is the atrium. The lower chamber, which pumps blood out of the heart, is the ventricle.
19. Circulation Through the Heart Blood enters the heart through the right and left atria. As the heart contracts, blood flows into the ventricles and then out from the ventricles to either the body or the lungs.
20. There are flaps of connective tissue called valves between the atria and the ventricles. When the ventricles contract, the valves close, which prevents blood from flowing back into the atria.
21. At the exits from the right and left ventricles, valves prevent blood that flows out of the heart from flowing back

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Retrieved Text: 1. What structural features of arteries and veins lead to an equilibrium in blood flow into and out of any given organ? Consider the relationship of flow to pressure and resistance in your answer (F=P/R).
2. Explain what is different and/or similar between the autonomic regulation of cardiac output and blood pressure.
In the following paragraphs I have explained the concepts of hemodynamics. Fishing-out the answer you require won't be difficult once you grasp the concepts. Also please refer to the attached PowerPoint Slides as referred in the material below.
First let me explain the equilibrium in blood flow. To understand the concept off equilibrium and how the structural features of arteries and veins affect that equilibrium we have to first understand the term cardiac output (CO), which means the rate of blood flow out of the heart (expressed in L/min). The heart is the central driver of the circulatory system and by the actions of constant contraction and relaxation the heart pumps blood throughout the whole body. Oxygenated blood from the heart first goes into the aorta, which is the largest artery of the body. Blood then goes into smaller and even smaller arterioles and then finally enters the capillaries. This is the region of micro-circulation. At the location of microcirculation oxygen, glucose and various enzyme substrates exchange with cells of the body take place. Capillaries pass blood to venules. Venules carry de-oxygenated blood to the right side of the heart from where it enters the lungs to get oxygenated again and to be circulated back to the

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Retrieved Text: As the arteries proceed to the proper tissues of the body, they divide and subdivide till they are no longer visible to the unassisted eye, and they finally break up into minute vessels named capillaries, the size of which is tolerably uniform for each organ. These communicate freely with each other and form a mesh or web, the arrangement of which presents variations corresponding to the structure of the organ in which they exist, being ladder-like in muscle, tuft-like in the kidney, and basketlike round the lobules of fat and of glands.
The wall of the capillaries is formed of a delicate basement membrane with a lining of flattened cells (endothelium), or even of the cells alone. Through this thin wall the white corpuscles of the blood seem to be able to bore without leaving any rent behind them, just as a needle may be thrust through the wall of a soap-bubble and withdrawn without causing the bubble to burst. The corpuscles then become free, and can move about in the interspaces of the adjoining tissues; but whether they die there or reenter the vessels is unknown. This process, in which the white corpuscles pass out of the vessels, is named diapedesis. The current of blood is not always the same in the same capillary vessel, the direction being dependent upon the increase of pressure behind, that is, on the arterial side, or the relief of pressure in front or on the venous side. In examining the circulation in the capillaries it will be seen that they

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======= Instance Index 91 =========
Input Text: Answer the following question given this paragraph: 

All alkanes are composed of carbon and hydrogen atoms, and have similar bonds, structures, and formulas; noncyclic alkanes all have a formula of CnH2n+2. The number of carbon atoms present in an alkane has no limit. Greater numbers of atoms in the molecules will lead to stronger intermolecular attractions (dispersion forces) and correspondingly different physical properties of the molecules. Properties such as melting point and boiling point (Table 20.1) usually change smoothly and predictably as the number of carbon and hydrogen atoms in the molecules change. Properties of Some Alkanes[3] Alkane.


Q: All alkanes are composed of carbon and hydrogen atoms, and have similar bonds, structures, and formulas; noncyclic alkanes all have a formula of cnh2n+2. the number of carbon atoms present in an alkane has what?

 Choices:

- crippling limit

- such limit

- no limit

- done limit

A:

Target Text: no limit

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Retrieved Text: Cycloalkanes are named based on the number of C atoms in them, just like regular alkanes, but with the prefix cyclo- on the name. What are the names of the three smallest cycloalkanes?
Cycloalkenes are named similarly to cycloalkanes (see Exercise 1). What are the names of the cycloalkenes with five, six, and seven C atoms?
Draw the carbon backbone of all noncyclic alkanes with only four C atoms.
Draw the carbon backbone of all noncyclic alkanes with only five C atoms.
Cyclic alkanes can also have substituent groups on the ring. Draw the carbon backbone of all cyclic alkanes with only four C atoms.
Cyclic alkanes can also have substituent groups on the ring. Draw the carbon backbone of all cyclic alkanes with only five C atoms.
Draw and name all possible isomers of pentene.
Draw and name all possible normal (that is, straight-chain) isomers of heptyne.
Polyunsaturated alkenes have more than one C–C double bond. Draw the carbon backbone of all possible noncyclic polyunsaturated alkenes with four C atoms and two double bonds. What are the complete molecular formulas for each possible molecule?
Draw the carbon backbone of all possible five-carbon cyclic alkenes with two double bonds, assuming no substituents on the ring.
If a hydrocarbon is combined with enough halogen, all the H atoms will eventually be substituted with that halogen atom. Write the balanced chemical reaction between ethane and excess chlorine.
If a hydrocarbon is combined with enough halogen, all the H atoms will eventually be substituted with that halogen atom. Write the balanced chemical reaction between butane and excess bromine.
Molecules with multiple

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Retrieved Text: The largest database1 of organic compounds lists about 10 million substances, which include compounds originating from living organisms and those synthesized by chemists. The number of potential organic compounds has been estimated2 at 1060—an astronomically high number. The existence of so many organic molecules is a consequence of the ability of carbon atoms to form up to four strong bonds to other carbon atoms, resulting in chains and rings of many different sizes, shapes, and complexities.
The simplest organic compounds contain only the elements carbon and hydrogen, and are called hydrocarbons. Even though they are composed of only two types of atoms, there is a wide variety of hydrocarbons because they may consist of varying lengths of chains, branched chains, and rings of carbon atoms, or combinations of these structures. In addition, hydrocarbons may differ in the types of carbon-carbon bonds present in their molecules. Many hydrocarbons are found in plants, animals, and their fossils; other hydrocarbons have been prepared in the laboratory. We use hydrocarbons every day, mainly as fuels, such as natural gas, acetylene, propane, butane, and the principal components of gasoline, diesel fuel, and heating oil. The familiar plastics polyethylene, polypropylene, and polystyrene are also hydrocarbons. We can distinguish several types of hydrocarbons by differences in the bonding between carbon atoms. This leads to differences in geometries and in the hybridization of the carbon orbitals.
Alkanes, or saturated hydrocarbons, contain only single covalent bonds between carbon atoms. Each of the carbon atoms in an alkane has sp3 hybrid orbitals and is bonded to four other

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Retrieved Text: The number of organic compounds, which are present around us and in our environment, is infinite. The large numbers are credited to the property of catenation as exhibited by carbon. Carbon can make four strong bonds; which, in turn, results in the formation of chain and ring structures. As the name indicates, hydrocarbons are organic compounds of hydrogen and carbon. Although the hydrocarbons are composed of only carbon and hydrogen, they occur in varied forms. This diversity can be attributed to the fact that hydrocarbons are present in the form of linear compounds, branched-chain structures, and ringed forms. The most common and the simplest hydrocarbon is methane. Hydrocarbons are versatile in their utility and are also present in crude oil, coal, natural gas, and other sources of energy; naturally.
Nonetheless, hydrocarbons never miss a chance to play a significant role in our daily life. The fuels that we use as sources of energy like CNG and LPG are nothing but a mixture of hydrocarbons only. Besides the uses mentioned above, the hydrocarbons render other great advantages as well. Let’s discuss the hydrocarbons in detail.
I. Saturated Hydrocarbons: The saturated hydrocarbons contain only carbon-carbon and carbon-hydrogen single bonds. They include open-chain as well as closed-ring structures. Alkanes and cycloalkanes are examples of saturated hydrocarbon; which are formed when different carbon atoms join to form an open-chain or a ringed structure.
II. Unsaturated Hydrocarbons: The unsaturated hydrocarbons contain multiple bonds; carbon makes double or triple bonds with other carbon atoms. The unsaturated hydrocarbons are of two types; alkene (containing double bonds)

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Retrieved Text: Alkanes (also known as paraffins or saturated hydrocarbons) are chemical compounds that consist only of hydrogen and carbon atoms and are bonded exclusively by single bonds (i.e., they are saturated compounds) without any cycles (or loops; i.e., cyclic structure). With the formula CnH2n+2, Alkanes belong to a homologous series of organic compounds in which the members differ by a constant relative molecular mass of 14. They have two main commercial sources: crude oil and natural gas.
Each carbon atom has 4 bonds (either C-H or C-C bonds), and each hydrogen atom is joined to a carbon atom (H-C bonds). A series of linked carbon atoms is known as the carbon skeleton or carbon backbone. The number of carbon atoms is used to define the size of the alkane (e.g., C2-alkane).
The simplest possible alkane (the parent molecule) is methane, CH4. There is no limit to the number of carbon atoms that can be linked together, the only limitation being that the molecule is acyclic, is saturated, and is a hydrocarbon. Saturated oils and waxes are examples of larger alkanes where the number of carbons in the carbon backbone is greater than 10.
Alkanes are not very reactive and have little biological activity. Alkanes can be viewed as a molecular tree upon which can be hung the more biologically active/reactive portions (functional groups) of the molecule.

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Retrieved Text: In organic chemistry, compounds composed of carbon and hydrogen are divided into two classes: aromatic compounds, which contain benzene and other similar compounds, and aliphatic compounds (G. aleiphar, fat, oil), which do not. In aliphatic compounds, carbon atoms can be joined together in straight chains, branched chains, or rings. They can be joined by single bonds (alkanes), double bonds (alkenes), or triple bonds (alkynes). Besides hydrogen, other elements can be bound to the carbon chain, the most common being oxygen, nitrogen, sulfur, and chlorine.
The simplest aliphatic compound is methane (CH4). Aliphatics include alkanes such as fatty acids and paraffin hydrocarbons, alkenes (such as ethylene) and alkynes (such as acetylene).
Most aliphatic compounds are flammable, thus allowing hydrocarbons such as methane to fuel Bunsen burners in the laboratory, whereas acetylene is used in welding.
^ International Union of Pure and Applied Chemistry (1995). "Aliphatic compounds". Compendium of Chemical Terminology Internet edition.
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Aliphatic_compound". A list of authors is available in Wikipedia.

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Retrieved Text: The increasingly large number of organic compounds identified with each passing day, together with the fact that many of these compounds are isomers of other compounds, requires that a systematic nomenclature system be developed. Just as each distinct compound has a unique molecular structure which can be designated by a structural formula, each compound must be given a characteristic and unique name.
Such common names often have their origin in the history of the science and the natural sources of specific compounds, but the relationship of these names to each other is arbitrary, and no rational or systematic principles underly their assignments.
A rational nomenclature system should do at least two things. First, it should indicate how the carbon atoms of a given compound are bonded together in a characteristic lattice of chains and rings. Second, it should identify and locate any functional groups present in the compound. Since hydrogen is such a common component of organic compounds, its amount and locations can be assumed from the tetravalency of carbon, and need not be specified in most cases.
 A root or base indicating a major chain or ring of carbon atoms found in the molecular structure.
 A suffix or other element(s) designating functional groups that may be present in the compound.
 Names of substituent groups, other than hydrogen, that complete the molecular structure.
As an introduction to the IUPAC nomenclature system, we shall first consider compounds that have no specific functional groups. Such compounds are composed only of carbon and hydrogen atoms bonded together by sigma bonds (all carbons

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Retrieved Text: The numerous organic compounds can be grouped into a comparatively small number of series or families of compounds known as homologous series. The simplest series of compounds in organic chemistry is the alkanes. We shall study this series to illustrate what a homologous series means.
The alkanes are a series of hydrocarbons with a general molecular formula of CnH2n + 2, where n is a whole number with a value of one or more.
From the table below, we see that each individual member of the alkane series differs from the preceding or the following member by one carbon atom and two hydrogen atoms, i.e. –CH2– group. Such a family of compounds is known as a homologous series and each individual member is referred to as a homologue.
A homologous series is a family of organic compounds which follows a regular structural pattern, in which each successive member differs in its molecular formula by a –CH2 – group.
Other homologous series include the alkenes, CnH2n, the alkanols, CnH2n+1 OH, and the carboxylic acids, CnH2n+1 COOH. Homologous series have the following common characteristics.
General Molecular Formula: All members share a general molecular formula, i.e., CnH2n + 2 for the alkanes, CnH2n for the alkenes, and so on.
Difference Between Successive Homologues: Each successive member in such a series differs in its molecular formula by the addition of a –CH2– group and in its relative molecular mass by an increase of 14.
Physical Properties: The physical properties of the members change gradually as the number of carbon atoms per molecule increases. For example, the boiling

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Retrieved Text: Propane is a fossil fuel and a component of natural gas. Over millions of years it formed from the organic remains of organisms and is mined from underground deposits. Propane gas is an organic compound made of three molecules of carbon atoms bonded with eight hydrogen atoms. The type of carbon-carbon carbon-hydrogen bonds determines the structure of propane molecules, which follows the same pattern as other types of natural gasses like methane and butane.
The chemical formula of propane is C3H8.
Propane is classified as an organic compound because it contains carbon. It is further categorized as a hydrocarbon because it belongs to a group of organic compounds that are made of only carbon and hydrogen. More specifically, propane is a type of hydrocarbon called an alkane. The atoms in alkane molecules are held together by single covalent bonds, and carbon atoms always form four covalent bonds.
Alkanes follow a general formula with a set ratio of carbon atoms to hydrogen atoms: C_nH2_n+2. The simplest alkane is methane, otherwise known as natural gas. It contains one carbon atom bonded to four hydrogen atoms. For methane, n = 1, so the number of hydrogen atoms it has is equal to 2(1)+2 which equals 4. Ethane contains two carbon atoms bonded together, and each carbon is bonded to three hydrogen atoms for a total of six hydrogen atoms. Propane has chain of three carbon atoms, with a chemical formula of C3H8, because a chain of three carbons require 2(3)+2 hydrogen atoms, which equals eight. Butane, another common alkane used as fuel

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Retrieved Text: The alkanes and cycloalkanes, with the exception of cyclopropane, are probably the least chemically reactive class of organic compounds. Alkanes contain strong carbon-carbon single bonds and strong carbon-hydrogen bonds. The carbon-hydrogen bonds are only very slightly polar; therefore, there are no portions of the molecules that carry any significant amount of positive or negative charge that can attract other molecules or ions. Alkanes can be burned, destroying the entire molecule (Alkane Heats of Combustion), alkanes can react with some of the halogens, breaking carbon-hydrogen bonds, and alkanes can crack by breaking the carbon-carbon bonds.

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Retrieved Text: Alkanes are hydrocarbons that only consist of single bonds. The ratio of carbon atoms to hydrogen atoms in alkanes is always in the form of n: 2n+2.
Alright. Let's talk about alkanes. And alkanes are hydrocarbons, compounds consisting of hydrogen and carbon, that only consist of single bonds, okay? Just single bonds in this carbon chain, this carbon back bone. So the formula for this is going to be CNH2N+2. Okay. So let's talk about several different types of alkanes you might see and come across.
So the first one, the simplest one is methane. Methane is CH4 consisting of one carbon and four hydrogen. And this is [IB] when you use methane, you [IB] this is like a natural gas, gas that might come from our body, something like that is methane. Okay? And notice the prefix meth, is dealing with one carbon, okay?
Next one is ethane. Ethane is dealing with two carbons. The prefix eth, is talking about two carbons and this is typically using c talking about different types of reactions [IB] and some things like that. This is ethane is typially used as a catalyst. Meaning that it helps the reaction move along. In fact three carbons we're going to take the three carbon chain it's going to have a prefix of prop. Meaning three carbons. And this is used, and you're talking about propane gas, propane tanks and things like that. You've probably heard of that when you go camping. You use that with fuel, those are you simplest fuel used for cooking

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Retrieved Text: · Instead of gaining and loosing electrons, carbon shares its 4-electrons with another element or carbon to form molecule.
· Covalent bonds are formed as a result of sharing of electrons. Example- H2, O2, N2. Covalent compounds have low melting point and boiling point due to small intermolecular forces.
· H2forms by sharing valence electrons (1 per atom of H) and produce single bond between two hydrogen atoms.
· O2 forms by sharing valence electrons (2 per atom of O) and produce double bond between two oxygen atoms.
· N2forms by sharing valence electrons (3 per atom of N) and produce triple bond between two nitrogen atoms.
· Methane, CH4is simple carbon compounds and used as a fuel on large scale and also a major component of CNG (Compressed Natural Gas). Methane formed due to sharing of 4 valence electrons of carbon with 4 hydrogen atoms.
Carbon have three allotropes i.e. Diamond, Graphite and fullerene.
Diamond formed due to rigid three dimensional structures of carbon atoms because each carbon atom bonded to another 4 carbon atoms. It is hardest substance.
Graphite formed due to presence of hexagonal array layers above one another, and layers of hexagonal arrays formed because each carbon atom bonded to another 3 carbon atoms with 2 single and 1 double bond. It is smooth, slippery and very good conductor of electricity.
Fullerenes (C-60) are also an allotrope of carbon in which carbon atoms are arranged in football like shape.
Carbon shows versatile nature because it has two characteristics features which are catenation and tetravalency. These both feature gives large numbers of compounds.
Catenation

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Retrieved Text: Because they are saturated compounds, the organic, hydrocarbon compounds, alkanes, tend to show very little reactivity. However, there are a few reactions that alkanes can and do undergo under specific conditions. These reactions include combustion, substitution and cracking. The reactions of alkanes are very important in everyday life.
Combustion is the most important reaction of alkanes. Alkanes burn in oxygen to form carbon dioxide and water vapor. If there is insufficient oxygen for the reaction, carbon monoxide and sometimes even carbon is formed instead of carbon dioxide. In actuality, there is always a certain amount of carbon monoxide formed in the process.
This is the reaction that occurs in internal combustion engines. It is the production of these gases, carbon dioxide and water vapor, and even the carbon monoxide, that allows the useful work of engines.
Very large alkanes are not as useful to human as smaller, short-chained ones. As a result, large alkanes are often cracked to produce smaller, more useful alkanes. During this process, alkenes and hydrogen gas may also be formed. The cracking of alkanes is carried out at 450 degrees celcius over an aluminum oxide or silicon oxide catalyst.
Alkanes can be converted to halogenoalkanes via substitution. This reaction only occurs in light or at high temperatures. As the name suggests, a replacement is made. One or more hydrogen atoms on the alkane is replaced by one or more halogen atoms. This reaction occurs mainly with chlorine, bromine and iodine. The halogen, fluorine, however, does not form halogenoalkanes having reacted with alkanes. Instead, carbon and hydrogen

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Retrieved Text: The covalent bond ( a pair of shared electrons) is the most common form of linkage between atoms in organic chemistry and biochemistry.
Each element has its own characteristic number of bonds : its valency.
Each line represents a covalent bond, to be used to combine with other atoms.
Actually this is an over-simplification because these are only 2-dimensional. In fact, the 4 bonds of carbon are at about 109º to each other but in 3 dimensions. Another way of saying this is that the 4 bonds are each directed towards the corners of a regular tetrahedron (formed from 4 equilateral triangles), with the carbon atom in the centre!
Carbon is special, because of its four bonds which enable it to combine with other carbon atoms and form a chain. The other elements H, O, N etc are unable to form giant structures on their own.
The term organic has several connotations. Originally it meant something derived from a living organism plant or animal, rather than of mineral origin: inorganic.
Then it became used by chemists to cover compounds of natural origin which were found to be based on carbon, and the term was extended to cover similar and more complex compounds produced artificially, and often containing other elements.
With this proviso, the term organic may be used without much confusion between biologists and chemists (and, indeed biochemists)!
More recently, it has been used in a more general way to describe consumer products and production processes which are not based on chemical fertilisers or other artificial chemicals. In this sense, there is scope for

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Retrieved Text: Consider this: Millions of reactions of organic molecules are currently known, and that number is getting bigger by the day. That’s probably a scary thought. Can you imagine trying to learn all of them? The good news is that you don’t have to learn all the reactions of specific molecules because organic molecules often react in predictable ways based on what kinds of groups a particular molecule contains.
Alkanes (molecules containing just singly bonded hydrogen and carbon atoms) are pretty much inert under most conditions. Carbon, though, is unique among the elements in that it has the capability of forming stable compounds that have multiple bonds to other carbons, in addition to stable bonds to other non-carbon atoms, forming reactive centers. These reactive centers are called functional groups and are the reactive portions in an organic molecule. Chemists organize organic compounds based on what functional groups are present in a particular molecule.

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Retrieved Text: Alkenes. Showing top 8 worksheets in the category - Alkenes. Some of the worksheets displayed are Naming and drawing alkenes work and key, Alkenes and alkynes work and key02 25 10, Work, Alkanes and alkenes work, Chapter 8, Work alkenes, Chem1002 work 3 addition reactions model 1 addition, Naming alkenes work cr 305 h3c ch3.
Alkenes and Alkynes Worksheet and Key 1. Draw the line bond structures for the following alkenes, cyclic alkenes, and alkynes: a) alkenes that contain 4 carbon atoms (three possible) b) cyclic alkenes that contain 4 carbon atoms (three possible) c) alkynes that contain 4 carbon atoms (two possible, neither of them are cyclic alkynes) 2.
Naming Alkanes Alkenes And Alkynes. Displaying all worksheets related to - Naming Alkanes Alkenes And Alkynes. Worksheets are Naming and drawing alkenes work and key, Naming alkanes, Naming alkynes work 1 c4 305, Work naming and drawing alkanes, Naming alkanes alkenes and alkynes quiz 70, Alkenes and alkynes work and key02 25 10, Work for organic chemistry, Naming alkanes work 1.
Organic Nomenclature - Alkanes, Alkenes, Alkynes Naming organic compounds can be a challenge to any chemist at any level. Historically, chemists developed names for new compounds without any systematic guidelines. In this century, the need for standardization was recognized.

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Retrieved Text: Having spent millions and millions of dollars surveying, exploring, appraising, designing, and developing a site, what do we have to show for it? This depends very much on the type of reservoir. ‘Oil and gas’ isn’t just one category (or even two), but covers a very broad range of mixtures defined by their chemical components.
From a commercial point of view, everything in oil or gas can be considered a hydrocarbon, an inert substance, or a contaminant. In the vast majority of reserves, hydrocarbons make up the vast majority of the mass and volume. This is just as well since they are the part we are most interested in. Hydrocarbons are, as the name implies, compounds made entirely of carbon and hydrogen, which come in an astonishing variety of shapes and sizes because of carbon atoms’ tendency to bond together in chains and rings.
The more common type of hydrocarbons is the aliphatic group, consisting of ‘chains’ and most types of ‘rings’. The simplest is methane, which is a gas has just one carbon atom and four carbon atoms. As we add carbon atoms in a line we get ethane, butane, propane, and pentane, all of which are gasses at room temperature; six carbon atoms make up the backbone of hexane, which is a liquid. These form a class of compounds called alkanes, which continue as you add more carbon atoms, forming increasingly viscous liquids and eventually solids (polythene is technically a very large alkane). Variants on the alkanes are the cycloalkanes, which are simple loops; alkenes and

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Retrieved Text: Formula and structure: The propane chemical formula is C3H8 and is extended formula is CH3CH2CH2. Its molar mass is 44.097 g mol-1. The molecule is formed by a chain of three carbon atoms which are bound to 3 or 2 hydrogen atoms in order to complete the 4 bonds required to complete the octet of Lewis structure. The carbon atoms are sp3 hybridized, thus the molecule has free rotation and a tetrahedral conformation. Its chemical structure can be written as below, in the common representations used for organic molecules.
Occurrence: Propane is found as a constituent of natural gas. It is also present in crude oil together with butane, methane, butylene, isobutylene and others where is extracted from distillation.
Preparation: Propane is producing by the distillation of crude oil or by extraction from natural gas. It is not largely synthesized by chemical industry and there is a few methods for producing it. In crude oil extraction, it is a sub-product in the process to obtain gasoline and other more commercial substances and it is removing to avoid pipelines problems.
Physical properties: Propane is a colorless and odorless gas, but it is shipped as liquefied compressed gas. These melting and boiling point are -187.6 ºC and -42.1 ºC, respectively. Its density is 2.009 g mL-1. Propane, in a pure form or when combined with methane, ethane or propane, can easily ignite forming vapors lighter than air. It is not soluble in water, but is slightly soluble in acetone, ethanol and more soluble in ether, chloroform and benzene.
Chemical properties: Propane is

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Retrieved Text: There are 5 lectures in this section of science wherein you are going to learn about Carbon and its compound. This is a very important chapter of Science and accounts for about 23 marks with periodic classification of elements. In Carbon and its compound You will learn the following as per the syllabus: Covalent bonding in carbon compounds. Versatile nature of carbon. Homologous series, Nomenclature of carbon compounds containing functional groups (halogens, alcohol, ketones, aldehydes, alkanes and alkynes), difference between saturated hydrocarbons and unsaturated hydrocarbons. Chemical properties of carbon compounds (combustion, oxidation, addition and substitution reaction). Ethanol and Ethanoic acid (only properties and uses), soaps and detergents.
This is first lecture of the Carbon and its compound which is the fourth chapter and is very important for SA-2 as it covers about 15-18 marks in exams. In this session you will learn about the Carbon and its properties. As you know carbon is an element and it has 4 valence electrons in its outermost shell, its valence electron are responsible for the entire change in the behavior and thus it forms maximum number of compounds. You will study here the terms covalency, catenation, tetravalency. The you will learn about the occurrence of Carbon. Sharing of electrons by Carbon. Then you will study the properties of hydrogen and how it forms compounds with hydrogen.Occurrence of allotropes of Carbon i.e.,Diamond, Graphite and Buckministerfulerene. You will study the properties of all three isotopes and difference among the three. You will also discuss the term Allotrophy, organic, Inorganic compound, saturated and

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Retrieved Text: WHY ARE THERE LOTS OF SERIES of ORGANIC COMPOUNDS?
8. Introduction to General Organic Chemistry - Why so many series of organic compounds?
Why are there so many different organic molecules? What is a functional group in organic chemistry? What is a homologous series in organic chemistry? The term 'homologous series' is explained with a general definition or descriptions and illustrated with examples you may, or may not have come across, but you will by the end of your GCSE/IGCSE chemistry course! You might have already come across several organic molecules e.g. methane an alkane, ethene an alkene, ethanol an alcohol, ethanoic acid a carboxylic acid and ethyl ethanoate an ester. This page gives you some idea why such a variety of different molecules can exist based on carbon atoms combined with those of hydrogen, oxygen and nitrogen etc. The different types of organic molecules are classified in what are called homologous series. These revision notes on homologous series of organic compounds and the structure of functional groups in organic chemistry, should prove useful and are designed for the NEW AQA GCSE 9-1 chemistry, Edexcel GCSE 9-1 chemistry & OCR GCSE 9-1 chemistry (OCR Gateway Science & OCR 21st Century Science), in fact any GCSE (9–1), (9-5) & (5-1) science courses.
8. Why are there many families of organic compounds? - variety !
You need to be able to explain that the vast array of natural and synthetic organic compounds occur due to the ability of carbon to form families of similar compounds, 'linear' straight chains, branched chains and rings

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Retrieved Text: Lipids are nonpolar organic molecules that are insoluble in polar water but soluble in nonpolar organic solvents like ether, alcohol, and chloroform. Lipids show hydrophobic behavior. The behaviour is associated with the chemical structures of lipids. Lipids have high proportion of C-1-I bonds. C-1-I is non-polar in character. Phospholipids and cholesterol are lipids. They are important constituents of cell membranes. The most common lipids in plants and animals are fats.
oxygen atoms. Some figs also contain small amounts of phosphorus and nitrogen. They contain a much smaller proportion of oxygen than carbohydrates. For example the formula of the fat tristearin is C5,F111006.
The building blocks of fat molecules are fatty acids and glycerol. Fatty acids contain long hydrocarbon chains bonded to carboxyl (COOH) groups. Glycerol is a three-carbon alcohol, with each carbon bearing a hydroxyl (OH) group. Three fatty acid molecules combine with one glycerol molecule. They are attached to the three carbon atoms in the glycerol backbone.
The fats with three fatty acids are called triglyceride neutral fat or triacylglycerol. The glycerol portion of every fat molecule is the same. But there are many kinds of fatty acids. Therefore, there are many kinds of fats. Fatty acid molecules differ in the length of their carbon chains aud in the ways the carbon atoms combine. The most common are e :en-numbered chains of 14 to 20 carbons.
Unsaturated fats: The% have double bonds. Their chains bend at the double bonds. So the fat molecules cannot align closely w ith one another. Therefore. they have low melting points. Thus the fat

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Retrieved Text: Take the prefix that corresponds to the total number of carbon atoms in the molecule (see naming alkanes in the alkanes page) and add anoic acid to form the name, e.g. CH3COOH is ethanoic acid.
With all these reactions a metal carboxylate salt is formed (e.g. sodium ethanoate).
When carboxylic acids are mixed and heated with alcohols, with a little concentrated sulphuric acid as a catalyst to remove the water product, esters are produced.
The reaction needs to be conducted in distillation appartus so that the product can be separated from the carboxylic acid starting material.
To name an acyl chloride take the prefix that corresponds to the total number of carbon atoms in the molecule (see naming alkanes in the alkanes page) and add anoyl chloide to form the name, e.g. CH3CH2COCl is propanoyl chloride.
Acyl chlorides perform the same reactions as their parent carboxylic acids, except that they react at room temperature and generate hydrogen chloride as a byproduct. They give very exothermic reactions. They must be kept in a dry atmosphere as they will react with the slightest amount of moisture to regenerate the carboxylic acid.
The carboxylic acid is refluxed with a dehydrating agent, such as phosphorus pentoxide (P2O5) and the product is distilled from the reaction mixture.
To name an acid anhydride take the prefix that corresponds to the total number of carbon atoms in the parent carboxylic acid (see naming alkanes in the alkanes page) and add anoic anhydride to form the name, e.g. (CH3CH2CO)2O is propanoic anhydride.
As with acyl chlorides, they perform the same reactions as

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Retrieved Text: Hemistry is the technology approximately breaking and forming of bonds among atoms. some of the most very important techniques for natural chemistry is breaking bonds C–H, in addition to C–C in numerous compounds, and basically, in hydrocarbons. between hydrocarbons, saturated hydrocarbons, alkanes (methane, ethane, propane, hexane and so on. ), are specifically appealing as substrates for chemical changes. the reason for this is that, at the one hand, alkanes are the most elements of oil and typical fuel, and hence are the important feedstocks for chemical undefined. nevertheless, those components are recognized to be the fewer reactive natural compounds. Saturated hydrocarbons should be referred to as the “noble gases of natural chemistry” and, if this is the case, the 1st consultant in their kinfolk – methane – could be in comparison with tremendous inert helium. As in all comparisons, this parallel among noble gases and alkanes isn't really totally actual. certainly the differences of alkanes, together with methane, were identified for a very long time. those reactions contain the interplay with molecular oxygen from air (burning – the most resource of energy!), in addition to a few mutual interconversions of saturated and unsaturated hydrocarbons. although, these kind of adjustments take place at increased temperatures (higher than 300–500 °C) and are typically characterised by way of a scarcity of selectivity. The conversion of alkanes into carbon dioxide and water in the course of burning is a really worthwhile approach – yet now not from a chemist perspective.
Hybrid fabrics have at the moment an excellent influence on a

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Retrieved Text: The research team includes, from left, Stasik Popov, Alex Bagdasarian, Hosea Nelson and Brian Shao. Nelson, the study's senior author, says there was surprising chemistry behind the reaction.
For more than a decade in the middle of the 20th century, chemists debated exactly what “carbocations” — molecules with a positively charged carbon atom — looked like. What is known as the “classical view,” which was taught at the beginning of that century, stated that the carbon in these molecules held the charge; the “non-classical view” held that the charge could also be shared by other nearby atoms. Both theory and experiment eventually proved that non-classical carbocations existed, and the debate faded away. Even if these structures exist, most chemists believed, they had no practical relevance.
Now, UCLA researchers have discovered a chemical reaction — that might someday be used to process petroleum into useful compounds — in which non-classical carbocations play key roles. The results, published July 27 in the journal Science, underscore the importance of non-classical cations — ions with fewer electrons than protons, and thus a positive charge. The findings also offer a new reaction to process alkanes, chemicals found in methane and propane gases that are notoriously hard to convert to other products.
“There’s both this reaction with a lot of practical potential, and this surprising chemistry behind the reaction,” said Hosea Nelson, a UCLA assistant professor of chemistry and biochemistry and senior author of the study.
“Now we have shown the importance of these species in explaining reactivity and selectivity,” said Kendall Houk, UCLA’s Saul Winstein

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Retrieved Text: After 250 research articles, Jim Dumesic, a professor of chemical engineering at the University of Wisconsin, Madison, usa, would much rather teach a classroom of seniors than promote a start-up company. But such is the commercial potential of his recent work that Dumesic now courts hard-nosed investors and earnest energy companies for venture capital and strategic partnerships for his start-up company, Virent Energy. The company's mission is to commercialise Dumesic's discovery of a process that could potentially unlock the use of one of the most benign forms of energy ever known -- hydrogen.
In the quest for fuels that produce few or no emissions, hydrogen is a recurring theme. Currently, catalytic steam reforming of methane provides for most of the world's hydrogen needs. The thermal energy required to operate the process at temperatures as high as 800c is costly and causes substantial emissions of carbon dioxide. Moreover, once hydrogen is stripped off methane, the residual carbon is deposited on the catalyst, thus sharply diminishing the overall efficiency of the process.
Dumesic's work promises to be a breakthrough in the quest for cleaner processes to produce hydrogen. Briefly, his method uses a catalyst and moderate temperatures to break glucose down to hydrogen in the presence of water. Glucose is a sugar, which is produced from cornstarch in large quantities. However, cheaper starting materials like sugarcane, corn, rice husk, and waste from paper mills and timber factories could be also used to produce it, because glucose is found abundantly in all biomass. It is this use of cheap and renewable

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Retrieved Text: Hydrocarbons containing at least three carbon atoms and non-aromatic carbon-to-hydrogen bonds are converted into hydrocarbons containing a new carbon-to-carbon linkage and having a higher carbon to hydrogen ratio by heating with an hydrogen-accepting olefine and a proportion of iodine (or hydrogen iodide, alkyl iodides or other compound which liberates iodine under the reaction conditions) of at least 0.05 mol. per mol. of hydrocarbon to be converted at at least 300 DEG C. to effect carbonto-hydrogen bond cleavage in the hydrocarbon feed and convert the olefine to paraffin. Conversions which may be effected are dehydrogenation of alkanes or aralkanes, e.g. isobutane to isobutene, n-butane to butenes and butadiene, ethyl benzene to styrene, o-methyl ethyl benzene to o-methyl styrene, and n-butyl benzene to 4 - phenyl - butadiene - 1,3; dehydrocoupling, e.g. propylene to diallyl, isobutene to dimethallyl, toluene to dibenzyl and stilbene; dehydrocyclization often with aromatization, e.g. n-hexane to benzene, n-heptane to toluene, n-octane to m-xylene and ethyl benzene, 2,5-dimethyl hexane to p-xylene, hexadiene-1,3 to benzene, hexane-1 to cyclohexene, o-diethylbenzene to naphthalene, o-methyl propyl benzene to naphthalene, n-butyl benzene to naphthalene, 2,3-diethyl naphthalene to anthracene, butylcyclohexane to naphthalene, and butylcyclopentane to indene; and dehydrogenation, often with aromatization of hydroaromatic hydrocarbons, e.g. cyclohexane to cyclohexene and benzene, and methylcyclohexane to toluene. In the case of acyclic hydrocarbons containing a quaternary carbon atom, dealkylation and/or isomerization may occur, e.g. 2,2,5-trimethylhexane gives p- and m-xylenes. The olefine used should be such that the sum of the standard free energy change for the hydrogenation of the olefine to the corresponding paraffin

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Score: 63.35015
Retrieved Text: This course will help high school students in the AP program as well as college students taking introductory chemistry. Professor Hovasapian expertly breaks down concepts so that any student can understand. Every lesson also ends with four fully worked-out examples.
This biochemistry online course is geared towards college students who want to understand the complex chemical processes occurring in all living organisms. Our most popular course has helped a generation of college students ace the infamous weeder course of Organic Chemistry.
Starkey teaches with visual models, real world examples, lab walkthroughs, and fully worked out examples to make sure you understand what is going on. Everything is covered in a standard ochem course from Drawing Structures to Reactions, Transformation, and Synthesis. Each lesson contains all the steps to correctly setup and complete the experiment, as well as discussion of the theory, procedures, and calculations necessary for the lab report.
Our highest college level chemistry course, Physical Chemistry explains chemical systems using physics. Professor Hovasapian breaks down the complex theory into easy-to-understand ideas which he solidifies with several fully worked-out examples at the end of each lesson. Read on for more details about radiation chemistry! Introduces carbon structures and interactions between molecules. Basic vocabulary and ideas are introduced concerning alcohols and hydrocarbons.
Combustion of a hydrocarbon is also discussed briefly. Alkanes and alkenes are both hydrocarbons that follow the standard nomenclature procedures. Learn whether alkanes and alkenes are saturated or unsaturated, which is more reactive, and how to name a compound by looking at its structure in this lesson.
When aromatic compounds

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Retrieved Text: Covalent bond or Molecular bond or Homopolar bond : A chemical bond formed between two non-metallic elements by the mutual sharing of one or more electron pairs is called covalent bond.
Covalency : The number of electron pairs which an atom of an element mutually shares with another atom or atoms of the same or different elements, so as to acquire a stable configuration like noble gases, is called co valency.
Properties of covalent (molecular) compound : (i) They have low melting point and boiling point. (ii) They have low density, i.e., their density is generally less than that of water. (iii) They are gaseous or volatile liquids or soft solids. (iv) They are insoluble in water, but soluble in organic solvents. (v) They are generally bad conductors of electricity.
Diamond is the purest crystalline form of carbon which is the hardest naturally occurring substance.
Other pure crystalline forms of carbon are graphite and fullerenes. In Buckminster- fullerene, each molecule has 60 atoms arranged in hexagons and pentagons.
Organic Chemistry : The branch of chemistry dealing with carbon compounds other than carbon monoxide, carbon dioxide and carbonates is called organic chemistry.
Catenation : The property of carbon atoms to link with other carbon atoms or the atoms of other elements with single, double or triple covalent bonds, so as to form large number of compounds is called catenation.
Saturated organic compounds : Organic compounds in which all the four valencies of carbon atoms are satisfied by single covalent bonds, are called saturated organic compounds.
Unsaturated organic compounds : Organic compounds in which a double

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Retrieved Text: Alkanes are the simplest group of hydrocarbons. They have the general formula CnH2n+2. The pages have been ordered by the number of carbon atoms in each molecule.
Wikimedia Commons has media related to Alkanes.
This page was last changed on 12 March 2019, at 08:30.

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Retrieved Text: Hydrocarbon, an organic chemical compound composed of carbon and hydrogen. Hydrocarbons may be gases, liquids, or solids. In nature, they are found mainly in plants, petroleum, natural gas, coal, and oil shale. Most burn readily and dissolve more readily in alcohol than in water. Some are toxic and some form an explosive mixture with air. Hydrocarbons are used as fuels and solvents and in the manufacture of industrial chemicals, explosives, plastics, synthetic rubber, dyes, drugs, and other products.
More than 100,000 hydrocarbons are known. The main reason there are so many of these compounds is that carbon atoms can unite in many different ways to form complex chain or ring frameworks. Different arrangements of atoms yield different molecules. For example, the formula C30 H62 (30 carbon atoms and 62 hydrogen atoms) represents 4,111,846,763 possible isomers—compounds whose molecules differ only in structure.
In chemistry, compounds closely related in structure to hydrocarbons are called hydrocarbon derivatives. Such compounds consist of carbon, hydrogen, and other elements, usually oxygen, nitrogen, chlorine, phosphorus, or sulfur. They are often named for the hydrocarbons to which they are most closely related. For example, the organic chloride compound most closely related to ethane is called ethyl chloride. Hydrocarbons and their derivatives form a large part of the subject matter of organic chemistry.
Hydrocarbons are divided into two main groups according to structure—aliphatic (or acyclic) hydrocarbons and cyclic hydrocarbons. They are further divided into groups of compounds having similar chemical properties. Members within a group are called homologs, and each complete group is called a homologous series. Neighboring

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Retrieved Text: Now that young chemists have learned how to name aliphatics and alkanes, they begin to understand the structure and shape of the resulting molecules. Chemguy uses models of molecules in this fourth of 16 organic chemistry videos. The best use of these videos is to assign them to chemistry learners who might have missed your in-class lesson on the topic.
In this bonding instructional activity, learners answer questions about ionic bonds and covalent bonds. They draw Lewis structures for compounds and show the molecular structure with the bonds between atoms.

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Input Text: Answer the following question given this paragraph: 

Chromosome Structural Rearrangements Cytologists have characterized numerous structural rearrangements in chromosomes, including partial duplications, deletions, inversions, and translocations. Duplications and deletions often produce offspring that survive but exhibit physical and mental abnormalities. Cri-du-chat (from the French for “cry of the cat”) is a syndrome associated with nervous system abnormalities and identifiable physical features that results from a deletion of most of the small arm of chromosome 5 (Figure 7.11). Infants with this genotype emit a characteristic high-pitched cry upon which the disorder’s name is based.


Q: Structural rearrangements of what include partial duplications, deletions, inversions, and translocations; duplications and deletions often produce offspring that survive but exhibit physical and mental abnormalities?

 Choices:

- phenotypes

- cells

- neutrons

- chromosomes

A:

Target Text: chromosomes

#### Retrieved Documents ####

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Score: 107.58371
Retrieved Text: Cytogenetics, also called chromosome analysis or karyotyping, involves the study of normal and abnormal chromosomes and their relationship to disease. Cytogenetic studies are often ordered to answer diagnostic, prognostic and predictive questions in the treatment of hematologic malignancies and solid tumors. Acute leukemias, lymphomas and chronic myeloid and lymphoid disorders are examined to establish the exact nature of the acquired genetic change. In most leukemias and lymphomas, changes in chromosome number (ploidy) or chromosome structure (rearrangements) are often observed. Rearrangements including translocations, inversions, and deletions can usually be detected under a light microscope.
We offer traditional G-banding for metaphase analysis which includes the detection of chromosomal translocations, insertions, inversions, deletions and duplications. In addition, proprietary wet lab processes increase the length of chromosomes and improve resolution, allowing our team members to ensure that the highest quality karyotype is produced.
See complete test details with printable description and specimen requirements.

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Retrieved Text: Call genomic rearrangments. Four types of rearrangements can be found: duplications, deletions, inversions, translocations. You can read more about the parameters and inputs from the DELLY website.
reference AlignedReadSet Optional Input reference genome. Not setting reference will disable split-read analysis.
input AlignedReadSet Optional Input BAM file for case sample.
folder BinaryFolder Optional Folder of input files.
algorithm string (no default) Type of rearrangement to call. There are four possible values: 'delly' for deletions; 'duppy' for duplications; 'invy' for inversions; and 'jumpy' for translocations.
dellyEnv string "../../lib/" DELLY location in the system. By default the location is assumed to be globally defined by the environment variable '$DELLY_HOME'.
distMergeCutoff int 300 Cutoff distance in bp for merging translocations. Only used if algorithm='jumpy'.
inversionOverlapMerge int 80 Percentage of overlap to merge inversions.
madCutoff int 5 Size of the insert-size cutoff. Only used if algorithm='delly'.
maxEpsilon float -1 Maximum allowed deviation of PE vs. SR duplication. Negative values of this parameter use delly defaults. Only used if algorithm is one of 'delly', 'duppy', or 'invy'.
minFlankSize int 13 Minimum length of the sequence flanking the putative breakpoint.
minMapQuality int 0 Minimum mapping quality for a paired-end read.
verbose boolean false Enable verbose output.

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Retrieved Text: There are a variety of genetic factors that may result in failure of a pregnancy to develop. These include aneuploidy (the gain or loss of a chromosome), chromosomal imbalances as a result of parentally harbored translocations or inversions, deletions or duplications of genetic information within chromosomes, and single-gene mutations. Broadly, genetic factors may be divided into embryonic errors derived from known parental chromosomal abnormalities and embryonic errors that arise de novo in apparently chromosomally normal parents.
Parental chromosome anomalies occur in 3-5% of couples with RPL as opposed to 0.7% in the general population. These include translocations, inversions, and the relatively rare ring chromosomes. Balanced translocations are the most common chromosomal abnormalities contributing to recurrent pregnancy loss. In couples with RPL, this abnormality is found more frequently in the female partner at a ratio of 2:1 up to 3:1 (female:male). In addition to genetic errors resulting from the parental balanced translocation, recent data from preimplantation genetic testing has shown that embryos resulting from parents harboring a balanced reciprocal translocation also have rates of unrelated chromosomal aneuploidy at rates exceeding 35%.
Translocations are where chromosome segments are exchanged between nonhomologous chromosomes. There are two main types of balanced translocation: reciprocal and Robertsonian. Robertsonian translocations involve two acrocentric chromosomes (numbers 13,14,15,21,22) that fuse near the centromere region with loss of the short arms. Studies indicate that when the Robertsonian translocation is maternal, there is a greater risk that the fetus will exhibit an unbalanced phenotype. In reciprocal translocations, the type of rearrangement results from breakage of nonhomologous chromosomes, with reciprocal

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Retrieved Text: Fully characterise tumour samples using long-read, real-time nanopore DNA and RNA sequencing. Long nanopore reads deliver comprehensive analysis of somatic mutations, structural variation – including insertions, deletions, and translocations – phasing, fusion transcripts, and base modifications.
Long sequencing reads enable resolution of challenging genomic rearrangements commonly found in cancer samples, including deletions, insertions, duplications, inversions and translocations. Using nanopore sequencing, read lengths in excess of 2 Mb have been generated.
Whole genome sequencing using direct, long-read nanopore sequencing technology delivers unprecedented insight into the cancer genome. Fully characterise the cancer genome and discover novel cancer biomarkers.
Targeted sequencing using long nanopore sequencing reads allows you to focus on specific genes or regions with known cancer associations. Characterise exons, introns, promoters, repetitive regions and structural variation in a single read — with no assembly required.
Oxford Nanopore Technologies does not sell a kit that enables CRISPR/Cas-mediated enrichment. Use of this technique may require rights to third-party owned intellectual property.
Utilise long reads to sequence full-length cDNA or direct RNA transcripts to reveal the true cancer transcriptome — even from single cells. Determine isoform expression, identify chimeric transcripts and study tumour progression. Use long reads to distinguish clonal and polyclonal variants.
Epigenetics is an increasingly important area of cancer research and base modifications have significant potential as diagnostic and prognostic indicators of disease. Direct nanopore sequencing does not require amplification, strand synthesis or bisulfite conversion, allowing detection of modified DNA or RNA bases alongside the nucleotide sequence.

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Retrieved Text: Prior to segregation in meiosis, homologous chromosomes pair and genetic material is swapped.
This is known as recombination and is key to ensuring offspring have different genetic traits to their parents. However, if homologous chromosomes (chromosomes of the same pair) misalign or non-homologous chromosomes pair, a number of different structural chromosome abnormalities may result including chromosome deletions / duplications; translocations and chromosome inversions.
This refers to the loss (deletion) or gain (duplication) of genetic material. A deletion or duplication is called interstitial when it occurs in the middle of the chromosome and terminal when it occurs at the tip of the chromosome.
The phenotypic (clinical) effect of a deletion or duplication depends on the genes involved. Deletions are generally more likely to have a phenotypic effect than duplication. Large deletions are likely to be lethal.
One of the commonest microdeletion syndromes is Di George syndrome, involving deletion of a region of chromosome 22 called 22q11. Di George syndrome can cause a variety of problems, including heart abnormalities, defects of the palate, problems of immunity and calcium control. Children and adults often have a characteristic facial appearance.
With the advent of array testing, an increasing number of recurrent microdeletion and microduplication syndromes are being recognised. This is discussed further in week 3.
A translocation describes when a portion of one chromosome is transferred to another chromosome. Translocations can be balanced or unbalanced depending upon whether there is a net gain or loss of genetic material. They are broadly classified into Reciprocal or Robertsonian translocations.
a. Reciprocal translocations arise when any two chromosomes swap non-homologous

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Retrieved Text: Posted by Amy Tarbox on March 21, 2011 .
Ben Raphael and his collaborators at Washington University in St. Louis have been awarded a five-year year grant from the National Institutes of Health (NIH), in the expected amount of $2.5 million, for their project “Computational Approaches For Structural Variation Studies In Genomes.” The proposed project will develop novel computational techniques to study structural variation, an important class of differences that distinguish individual genome sequences. Structural variants include duplications, insertions, deletions, inversions, and translocations of large blocks of DNA sequence. These differences have been implicated in several human diseases including autism and cancer. New genome technologies are enabling large-scale measurement of these variants, but application of these technologies demand new methods to interpret the resulting data.
Ben and his collaborators will develop computational approaches to facilitate the identification and characterization of structural variants. These approaches will be applied to data from human, cancer, mouse, and pathogen genomes in collaboration with several biomedical researchers. The proposed research will aid in the discovery of genetic variants associated with various human diseases, which in turn could lead to better diagnostics and/or personalized treatments for these diseases.

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Rank: 6
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Retrieved Text: ExonArrayDx – a novel, specialized service to evaluate one or more genes from a list of >460 genes for partial or full gene deletions or duplications defined at the exon level. The ExonArrayDx test is based on the use of a ultra-high resolution microarray-based comparative genomic hybridization (array CGH), which has a higher sensitivity for detecting deletions and duplications compared to MLPA and quantitative PCR (qPCR), to detect partial or complete gene deletions and duplications of clinically significant genes. GeneDx offers this service for disorders known to be caused by deletions or duplications within a single gene as well as for disorders due to haploinsufficiency or loss of function for a specific gene for which the frequency of gene deletions/duplications is currently not well established.
As a second tier test on a specimen in which previous sequence analysis did not identify a disease-associated mutation.
As a primary test in a Mendelian disorder due to haploinsufficiency when sequence analysis fails to identify a causative mutation; in particular when whole or partial gene deletions are a known cause for the disorder (i.e., STK11 deletion associated with Peutz-Jeghers syndrome or RAI1 deletion associated with Smith-Magenis syndrome).
As a confirmation test for deletion or duplication detected by MLPA or qPCR.
Carrier testing when a specific deletion or duplication has been identified in an affected relative (i.e., testing of carrier status of female relatives of an affected male with X-linked hydrocephalus due to L1CAM deletion).
Deletion/duplication analysis by ExonArrayDx may be requested for a single gene or for a custom panel of clinically related genes (up

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Retrieved Text: Question: Is there any suitable annotation tool for structural rearrangements?
I will ask a simple question regarding annotation method.
Firstly, I have found many structural rearrangement using DELLY, CREST and SVDetect.
Among many types of structural variants, I want to focus on structural rearrangement such as Inversion, Large deletion and translocation.(not SNPs, or Indels).
To know whether these rearrangement variants were reported previously and to find out more significant variants among them, I used annotation tool (Annovar) and I found that region-based and filter-based methods will fit for my purpose. Therefore, all my structural variants were annotated by gene based firstly and subsequently I used region-based and filter-based to find out more important variants.
So Is there any suitable or appropriate annotation tool for structural rearrangement?
It seems that annovar doesn't fit for rearrangement.
Check out this tool for annotation of translocations/deletions and inversions that result in gene fusions Oncofuse: Prediction Of Driver Gene Fusions From Ngs Data. As for deletions/amplifications, I believe that the general working strategy would be to identify the list of affected genes (this could be simply done by .bed intersection in Galaxy) and using open annotation services, such as DAVID for those genes.
any tools for annotating "canonical splice site variants"

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Rank: 8
Score: 72.411476
Retrieved Text: This is a second tier test and REQUIRES PERMISSION from ARUP's Genetic Counselor (800-242-2787, x2141) before ordering. Preferred initial test is the sequencing and deletion/duplication test.
Characteristics: Neurofibromatosis type 1 (NF1) demonstrates extreme clinical variability. Features include: cafe au lait macules, axillary or inguinal freckling, dermal fibromas, Lisch nodules (iris hamartomas), optic glioma, specific osseous lesions such as tibial pseudarthrosis or sphenoid dysplasia, learning disabilities (50 percent), scoliosis, vertebral dysplasia, and somatic overgrowth. Large NF1 locus deletions increase the risk for neurofibroma development, cognitive abnormalities and malignant peripheral nerve sheath tumors (MPNST).
Inheritance: Autosomal dominant; de novo mutations occur in 50 percent of cases.
Penetrance: 100 percent by adulthood.
Clinical Sensitivity: Approximately 5 percent of NF1 is caused by large NF1 locus deletions and 2 percent due to intragenic deletions.
Methodology: Multiplex ligation-dependent probe amplification (MLPA) to detect large NF1 locus and intragenic deletions/duplications.
Limitations: Diagnostic errors can occur due to rare sequence variations. Single base pair substitutions, small deletions/duplications, regulatory region mutations, and deep intronic mutations will not be detected. Large deletions/duplications of exons 11and 20 will not be detected. The breakpoints for large deletions/duplications will not be determined.

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Rank: 9
Score: 71.81516
Retrieved Text: Detect causal F8 variant in individuals with established severe hemophilia A and determine carrier status in at-risk females with severely affected male relatives. For mild to moderate hemophilia A, Hemophilia A (F8) sequencing (2001747) is preferred.
Characteristics: Severe deficiency of factor VIII clotting activity is associated with spontaneous joint or deep tissue bleeding. Moderate or mild deficiency is associated with prolonged bleeding after tooth extractions, surgery, or injuries and recurrent or delayed wound healing.
Incidence: 1 in 4,000-5,000 live male births worldwide; rare in females.
Methodology for Inversions: F8 intron 22-A and intron 1 inversions detected by inverse PCR and electrophoresis.
Methodology for Sequencing: Bidirectional sequencing of the F8 coding region and intron-exon boundaries.
Methodology for Deletion/Duplication: Multiplex ligation-dependent probe amplification (MLPA) to detect large deletions/duplications in the F8 coding region.
Limitations: Diagnostic errors can occur due to rare sequence variations. Regulatory region and deep intronic mutations, other than the F8 intron 22-A and intron 1 inversions, will not be detected. Deletions/duplications in exon 23 will not be detected.
F8 inversion testing is performed on all specimens. If inversion testing does not explain the clinical scenario, then F8 gene sequencing will be added. If inversion testing and sequencing does not explain the clinical scenario, then deletion/duplication testing will be added. Additional charges apply.

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Rank: 10
Score: 71.49786
Retrieved Text: Dihydropyrimidine dehydrogenase (DPYD) is the initial and rate-limiting enzyme in the 3-step pathway of uracil and thymidine catabolism and in the pathway leading to the formation of beta-alanine. DPYD is the major enzyme involved in breakdown of 5-fluorouracil which is one of the most widely used drugs for cancer chemotherapy.
DPYD deficiency is a clinically heterogeneous disorder. Patients with a nearly complete enzyme defect often show convulsive disorders, motor retardation and mental retardation. The frequency of a homozygous defect in DPYD gene is estimated to be 1:10.000 in most populations. Individuals with enzymatic activities in the heterozygous range can experience acute 5-fluorouracil toxicity when they receive 5-fluorouracil treatment. The number of individuals that have only one intact copy of the DPYD gene might be as high as 3%. It is estimated that 0.5% of colorectal cancer patients that receive 5-fluorouracil treatment die from adverse drug reactions.
The DPYD gene is one of the longest human genes. It is located on chromosome 1p21.3 and comprises 23 exons that span 843 kb of genomic DNA, about 98 Mb from the p-telomere. DPYD defects due to gene rearrangements could be a frequent cause of DPYD deficiency. This P103-B2 probemix contains MLPA probes for each of the 23 exons. In view of the large size of the introns, two probes are present for 12 of the exons. Three probes are present for exon 1. Also present is a probe specific for the IVS14+1G>A mutation which leads to the skipping of exon 14 in the process of DPYD pre-mRNA splicing. This SALSA MLPA

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Score: 71.35737
Retrieved Text: Man and ape. Comparative genomics is relating the differences between species in the genome to the phenotype. When the first comparisons between human and chimpanzee were published in 2005, neuroscientists were excited that this comparison would show what makes our brain human. A glance at the genes clusters that rapidly evolved during human-specific evolution was sobering. Many of the genes that rapidly evolved are immune-regulatory genes, highlighting our constant struggle with some parasites, bacteria and viruses and our arrangement with the microbiome, the cloud of microbes contribute ten times as many cells to our bodies than we do. Prominent genes such as FOXP2, a gene found to be disrupted in patients with developmental language problems, and most other brain genes barely show up as a group in comparative genomics.
Segmental duplications and human evolution. Recent human evolution did not only leave traces at the single-base pair level that allows for the discovery of individual sequence differences but also larger structural genomic variants including segmental duplications. Recurrent microdeletions such as the 15q13.3, 16p13.11 or 15q11.2 microdeletions occur relatively frequently because the genomic sequence of these deletions is located between segmental duplications (Figure 1). These segmental duplications are so similar that the DNA replication machinery sometimes mistakes one duplication for the other (e.g. the “right flanking duplication” for the “left flanking duplication”). Thereby, the intervening sequence is either deleted or duplicated. Segmental duplications are relatively human-specific, for example a paralogue region for the 15q13.3 microdeletion is not present in rodents. Even in chimpanzees, the segmental duplications that give rise

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Rank: 12
Score: 69.07531
Retrieved Text: Test Information: Mitochondrial complex IV (cytochrome c oxidase), one of five complexes of mitochondrial respiratory chain that plays a critical role for generating ATP, contains 10 nuclear encoded subunits and 3 mitochondrial encoded subunits. Five gene products are required for its assembly. This panel will analyze 12 genes that are involved in functionality of the complex IV. Every coding exon of these 10 genes will be examined, thus, it is diagnostic for mitochondrial complex IV deficiency.
Special Notes: All exons of these 10 genes are examined by NGS and Sanger Sequencing. Exonic variants and intronic variants within 20bp of the exon/intron boundary will be reported. This massively parallel sequence analysis (MitomeNGS) will not detect genomic structural rearrangements (eg. deletions, duplications, inversions, etc.), large insertion mutations (e.g. ALU mediated insertion, etc), mutations within the promoter or deep intronic regions. Mutations and novel variants are confirmed by Sanger sequencing.
Sequence Analysis for the 10 genes in the Mitochondrial Respiratory Chain Complex IV Deficiency Panel by Massively Parallel Sequencing (MitomeNGS) can be ordered separately: COX10 (#3100), COX15 (#3545), COX4I2, COX6B1, FASTKD2 (#3555), LRPPRC (#3240), SCO1 (#3095), SCO2 (#3090), SURF1 (#3085), and TACO1 (#2745).
Requirements: Draw blood in an EDTA (purple-top) tube(s) and send 3-5 cc (Adults/Children).
Shipping Conditions: Ship at room temperature in an insulated container by overnight courier. Do not heat or freeze. Sample must arrive within 72 hrs.
Requirements: Send at least 5ug of purified DNA (minimal concentration of 50ng/uL; A260/A280 of ~1.7).
Shipping Conditions: Ship at room temperature in an insulated container by overnight courier. Do not heat or freeze.

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Retrieved Text: Genetic changes causing dramatic brain size expansion in human evolution have remained elusive. Notch signaling is essential for radial glia stem cell proliferation and a determinant of neuronal number in the mammalian cortex. We find three paralogs of human-specific NOTCH2NL are highly expressed in radial glia cells. Functional analysis reveals different alleles of NOTCH2NL have varying potencies to enhance Notch signaling by interacting directly with NOTCH receptors. Consistent with a role in Notch signaling, NOTCH2NL ectopic expression delays differentiation of neuronal progenitors, while deletion accelerates differentiation. NOTCH2NL genes provide the breakpoints in typical cases of 1q21.1 distal deletion/duplication syndrome, where duplications are associated with macrocephaly and autism, and deletions with microcephaly and schizophrenia. Thus, the emergence of hominin-specific NOTCH2NL genes may have contributed to the rapid evolution of the larger hominin neocortex accompanied by loss of genomic stability at the 1q21.1 locus and a resulting recurrent neurodevelopmental disorder.
The human brain is characterized by a large neocortex that forms the substrate for the development of human-specific higher cognitive functions (Lui et al., 2011; Molnar et al., 2006; Rakic, 2009), but evolutionary changes to our genome that underlie the increase in size and complexity of the human neocortex are poorly understood (Varki et al., 2008). Structural genomic variants account for 80% of human-specific base pairs and are therefore an important class of genomic regions to consider (Cheng et al., 2005). Of particular interest are loci where segmental duplications have created entirely new human-specific gene paralogs that are associated with cortical development, such as SRGAP2C (Dennis et al., 2012),

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Score: 68.06652
Retrieved Text: The Invitae Mucopolysaccharidosis Type II Test analyzes the IDS gene, which is associated with mucopolysaccharidosis type 2 (MPSII). This test is useful for the diagnosis of patients in whom MPS II deficiency is suspected due to clinical symptoms, biochemical findings, or abnormal newborn screening results.
Phenotypic features of MPS II can overlap with other MPSs and mucolipidosis type III a/b. Given the significant clinical overlap between these conditions, analyzing the genes associated with MPS I, MPS VII, mucolipidosis type III a/b and multiple sulfatase deficiency may be appropriate. These genes may be included at no additional charge.
Mucopolysaccharridosis type II (MPSII, Hunter syndrome) is a progressive, multi-system disorder that is caused by a deficiency of iduronate-2-sulfatase, an enzyme that is necessary for the breakdown of dermatan sulfate and heparan sulfate. Affected males are normal at birth after uncomplicated pregnancies, but symptoms begin to develop around two years of age. Increased accumulation of mucopolysaccharides leads to characteristic facial features such as thickened lips, enlarged tongue, a full lower aspect of the face, depressed nasal bridge, thickened eyebrows, and frontal bossing. Patients also develop hepatosplenomegaly, frequent ear infections, and a thickening of the vocal cords and airway that leads to hoarseness and sleep apnea. Umbilical and inguinal hernias may also develop and may reappear after surgical correction. Patients may develop hearing loss, short stature, joint contractures, spinal stenosis, and dysostosis multiplex, which is characterized by oar-shaped ribs, gibbus deformity, abnormal vertebrae, shortened and thickened clavicles, and trident-shaped hands. Carpal tunnel syndrome may also develop in childhood. Affected males do not,

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Rank: 15
Score: 67.77551
Retrieved Text: Cause: Pathogenic F9 gene mutations.
Methodology: Bidirectional sequencing of the entire F9 coding region and intron-exon boundaries and proximal promoter; Multiplex Ligation-dependent Probe Amplification (MLPA) to detect large F9 deletions/duplications.
Limitations: Diagnostic errors can occur due to rare sequence variations. Regulatory region mutations and deep intronic mutations will not be detected. The breakpoints of large deletions/duplications will not be determined. Large deletions/duplications in exon 1 may not be detected. Mutations in genes other than F9 will not be detected.

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Rank: 16
Score: 66.81188
Retrieved Text: Despite advances in sequencing, structural variants (SVs) remain difficult to reliably detect due to the short read length (<300bp) of 2nd generation sequencing. Not only do the reads (or paired-end reads) need to straddle a breakpoint, but repetitive elements often lead to ambiguities in the alignment of short reads. We propose to use the long-reads (up to 20kb) possible with 3rd generation sequencing, specifically nanopore sequencing on the MinION. Nanopore sequencing relies on a similar concept to a Coulter counter, reading the DNA sequence from the change in electrical current resulting from a DNA strand being forced through a nanometre-sized pore embedded in a membrane. Though nanopore sequencing currently has a relatively high mismatch rate that precludes base substitution and small frameshift mutation detection, its accuracy is sufficient for SV detection because of its long reads. In fact, long reads in some cases may improve SV detection efficiency. We have tested nanopore sequencing to detect a series of well-characterised SVs, including large deletions, inversions, and translocations that inactivate the CDKN2A/p16 and SMAD4/DPC4 tumor suppressor genes in pancreatic cancer. Using PCR amplicon mixes, we have demonstrated that nanopore sequencing can detect large deletions, translocations and inversions at dilutions as low as 1:100, with as few as 500 reads per sample. Given the speed, small footprint, and low capital cost, nanopore sequencing could become the ideal tool for the low-level detection of cancer-associated SVs needed for molecular relapse, early detection, or therapeutic monitoring.
Alexis L. Norris, Rachael E. Workman, Yunfan Fan, James R. Eshleman, Winston Timp.

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Retrieved Text: Ischiopatellar dysplasia, also known as Small Patella Syndrome, is an autosomal dominant skeletal dysplasia. It is characterized by patellar aplasia or hypoplasia, as well as anomalies of the pelvis and feet, including disrupted ossification of the ischia and inferior pubic rami.
Defects in the T-box transcription factor TBX4 gene on chromosome 17 is the main cause of Small Patella Syndrome. The protein encoded by this gene is TBX4 which has been established to be important in the developmental pathways of the lower limbs and the pelvis in humans. Microduplications in the 17q23.1-q23.2 have also been associated with clubfoot etiology, linking this medical condition to early limb development (Alvarado et al., 2010).
The TBX4 gene (8 exons) spans ~27 kb of genomic DNA and is located on 17q23, 56 Mb from the p-telomere. The P390-A1 probemix contains one probe for each exon of TBX4 and two probes for exon 8.
This probemix furthermore contains several probes for surrounding genes, such as the TBX2 region (5 probes), as well as probes for regions upstream and downstream of the TBX2 and TBX4 genes, in the 17q region. Microdeletions in TBX2 have been linked to congenital microcephaly (Nimmakayalu et al., 2011). In addition, 11 reference probes are included in this probemix, detecting several different autosomal chromosomal locations.
SALSA® MLPA® probemixes are designed to detect deletions/duplications of one or more sequences in the aforementioned genes in a DNA sample. Heterozygous deletions of recognition sequences should give a 35-50% reduced relative peak area of the amplification product of that probe. Note that a mutation or polymorphism

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Retrieved Text: Mutations in TGFBR1 and TGFBR2 have been reported to cause a new aortic aneurysm syndrome characterized by hypertelorism, bifid uvula and / or cleft palate (Loeys, B. L. et al., 2005, Nat Genet). In addition, mutations in TGFBR2 have been reported to cause Marfan syndrome (Mizuguchi, T. et al., 2004, Nat Genet). The database of genome variants mentions no copy number changes of this genomic region in healthy individuals (see http://projects.tcag.ca/variation/). TGFBR1 and TGFBR2 are transmembrane serine / threonine receptor kinases. Growth factor TGFB1 regulates cell cycle progression by a signaling mechanism that involves binding to TGFBR2 and activation of TGFBR1.
The TGFBR1 gene (9 exons) spans ~49.1 kb of genomic DNA and is located on chromosome 9q22, ~100.9 Mb from the p-telomere. The TGFBR2 gene (8 exons) spans ~87.6 kb of genomic DNA and is located on chromosome 3p24, ~30.7 Mb from the p-telomere.
The P148-B1 probemix contains probes for all exons of the TGFBR1 and TGFBR2 genes with the exception of TGFBR2 exon 2 which is only present in one transcript variant. Several probes are present for exon 1 of both genes. In addition, 11 reference probes are included in this probemix, detecting several different autosomal chromosomal locations.
This SALSA® MLPA® kit is designed to detect deletions/duplications of one or more sequences in the aforementioned genes in a DNA sample. Heterozygous deletions of recognition sequences should give a 35 50% reduced relative peak area of the amplification product of that probe. Note that a mutation or polymorphism in the sequence detected by a probe can also cause

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Retrieved Text: SD026 Artificial Duplication DNA: MRC-Holland has prepared a mixture of female genomic DNA from healthy individuals and a carefully titrated amount of plasmid that contains the target sequence recognised by several probes present in the selected MLPA probemixes. The use of SD026 in MLPA reactions performed with the selected MLPA probemixes will therefore show a duplication of several sequences. This SD026 can be ordered separately.
Limb-girdle muscular dystrophies (LGMD) are a group of phenotypically and genotypically heterogeneous disorders, characterised by progressive weakness and atrophy of the muscles of the pelvic and shoulder girdle. Mutations of the Dysferlin gene (DYSF) are the cause of limb-girdle muscular dystrophy type 2B (LGMD2B). Patients with LGMD2B have symmetrical and selective involvement of proximal limb-girdle muscles. The disease shows wide intra- and interfamilial clinical variability. The age at onset ranges from 2 to 40 years, but the disease usually first appears in the second or third decade of life, with the development of proximal weakness in the lower limbs. Mutations in DYSF result in a cascade of events leading eventually to muscular dystrophy. The precise underlying mechanisms have yet to be elucidated.
The DYSF gene comprises 58 exons, spans ~233 kb of genomic DNA and is located on chromosome 2p13.2, approximately 72 Mb from the p-telomere. Copy number changes of this genomic region are found in healthy individuals and can be found in the database of genome variants (see http://projects.tcag.ca/variation/).
This P268-A2 DYSF probemix contains probes for 40 different DYSF exons. In addition, 8 reference probes located on other chromosomal locations are included.
This SALSA®

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Retrieved Text: Array-based comparative genomic hybridization (aCGH) is a powerful tool for detecting copy number variations. It is a well-established method used to analyze genomic gains and losses ranging from duplications, deletions, unbalanced translocations, and aneuploidies.
Array CGH is a universal approach that enables the rapid screening of the entire genome. Test DNA and reference DNA are labeled with two different fluorophores and equal amounts are hybridized to a microarray. The microarrays contain either DNA or oligonucleotide probes representing small sections of chromosomes. Array CGH looks at chromosomal imbalances between the test DNA and the reference DNA and is capable of giving a holistic comparison of the genome.
The main objective of this study was to utilize the high resolution Innopsys InnoScan 910 to demonstrate the superior performance of the CYTAG™ CGH Labeling Kit in labeling DNA for CGH analysis on a 4x180 whole genome microarray.

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Retrieved Text: The variability, introduced by mutations, is the material on which selection works. This is the essence of natural selection and evolution.
Genetic variability is a measure of the tendency of individual genotypes in a population to vary from one another. Variability is different from genetic diversity, which is the amount of variation seen in a particular population. The variability of a trait describes how much that trait tends to vary in response to environmental and genetic influences. Genetic variability in a population is important for biodiversity, because without variability, it becomes difficult for a population to adapt to environmental changes and therefore makes it more prone to extinction.
Variability is an important factor in evolution as it affects an individual's response to environmental stress and thus can lead to differential survival of organisms within a population due to natural selection of the most fit variants. Genetic variability also underlies the differential susceptibility of organisms to diseases and sensitivity to toxins or drugs — a fact that has driven increased interest in personalized medicine given the rise of the human genome project and efforts to map the extent of human genetic variation such as the HapMap project.
The genetic variability in the human genome can be present in different forms, among which structural alterations (deletions, duplications and inversions), presence/absence of trasposable elements (Alu elements), and polimorphisms (SNPs, MNPs, STRs).

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Retrieved Text: The Hereditary Colorectal/Gastrointestinal Cancer Panel uses next-generation sequencing and deletion/duplication analysis to simultaneously analyze selected genes associated with an increased risk for colorectal and GI cancers. Approximately 5 to 10% of all colorectal cancers are believed to be hereditary. In general, the test is used when a patient's medical history and family history findings strongly suggest that there is an underlying genetic etiology of colorectal/GI cancer.
Twenty-two genes involved in hereditary colorectal/GI cancer are analyzed by the newly developed and clinically validated approach of Massively Parallel Sequencing (MPS) using Next Generation Sequence (NGS) technology. The genes analyzed by this panel are tabulated below. Sequencing of these genes is also available using the associated individual test codes.
APC, ATM, BMPR1A, BRCA1, BRCA2, CDH1, CDK4, CDKN2A, CHEK2, ENG, EPCAM*, MLH1, MSH2, MSH6, MUTYH, PALB2, PMS1, PMS2, PTEN, SMAD4, STK11, and TP53.
All coding exons of these 22 genes and at least 20 base pairs of flanking intronic sequences are analyzed. All exonic variants and intronic variants within 20 bp of the exon/intron boundary will be reported. Sequence analysis will not detect genomic structural rearrangements (e.g. heterozygous deletions, duplications, and inversions), large heterozygous insertion mutations (e.g. ALU mediated insertion), and mutations within the promoter or deep intronic regions. Mutations and novel variants detected by NGS are confirmed by Sanger sequencing.
The panel also includes gross copy number analyses of these genes by MLPA and/or aCGH. Certain exons with no known gross deletion/duplication mutations, or certain genes/exons with highly homologous sequences in the genome may not be evaluated by this copy number analysis.
A High

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Retrieved Text: BioNumerics lets you align and compare sequences of up to full chromosome length. With these comparative genomics tools, discontinuous alignments are calculated using seed and stretch-based sequence mapping, revealing genomic inversions, swaps, duplications, insertions and deletions. Mutation and SNP discovery can be performed on template-based multiple chromosome alignments, with optional selection of mutation type (intergenic, synonymous, non-synonymous or indel) and filtering of significant SNPs based on quality scores. dNdS analysis based on the ratio synonymous/non-synonymous mutations within gene clusters is available to predict evolutionary selection pressure on genes.
Extremely fast pairwise matching and alignment of N×N sequences of full chromosome size.
Seed and stretch based sequence matching, allowing for discontinuous alignments, including inversions, swaps, duplications, insertions and deletions.
Full-sequence based or coding sequence based alignment, using user-defined nucleic acid seeds and/or amino acid seeds.
Display of clickable N×N chromosome similarity matrix and associated clustering. The selected pair of chromosomes is displayed in the dot plot Cell panel. Direct and inverted matches are displayed in different color.
Clickable dot plot matrix, updating (1) currently selected stretch in the Stretches panel and (2) associated alignment in the Pairwise alignment panel.
Calculation of superstreches, i.e. larger clusters of stretches that contain no major discontinuities and that have a minimal overall homology.
Alignment of multiple chromosomes based upon selected template chromosome.
Display of overview panel and detailed multiple alignment panel.
Synchronized selection in overview, multiple alignment, dot plot, stretches and pairwise alignment panels.
Versatile search and display functions for features and subsequences on multiple chromosomes.
Search and display of mutations within multiple alignments, with discrimination between intergenic, synonymous, non-synonymous and Indel

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Retrieved Text: Home › Health › Are we done with invasive long needles for prenatal diagnosis!?
Traditionally, a long needle would be introduced through the skin of the abdomen all the way through the muscle layers of the abdominal wall and the uterus, then through the protective membranes to reach the water surrounding the fetus to obtain a sample that we would test for genetic abnormalities or mutations. This process is called Amniocentesis. Chorionic Villus Sampling or CVS is a similar procedure except that it is done at an earlier gestational age and is associated with higher risks. Both CVS and amniocentesis are used to obtain fetal cells that would aid in performing conventional karyotyping (Mapping and counting of the chromosomes) that would help with prenatal diagnosis of genetic diseases.
Chromosomal microarray analysis or CMA is a novel method that appears to be superior to karyotyping. CMA analyses chromosomes for a large number of genetic disorders. In addition to what karyotyping can usually detect, CMA detects copy number variations (deletions and duplications) that are beneath the radar of conventional cytogenetics. As an example, CMA detects genomic imbalances in up to 15% of children who otherwise were deemed to have “unexplained congenital anomalies,” in 6% of fetuses with ultrasonically detected structural abnormalities but normal karyotypes and in 2% of fetuses with normal ultrasound findings and karyotypes.
CMA does not require the relatively lengthy, uncomfortable and invasive procedure to obtain a sample. It only requires a regular blood sample like one would give when a blood test is requested.
The test is not perfect.

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Retrieved Text: Array CGH is a well-established method for investigating copy number variations. It is used to detect a variety of genomic gains and losses ranging from copy number variants, duplications and deletions, unbalanced translocations, and aneuploidies.
In an array CGH experiment, test DNA and reference DNA are labeled with two different fluorophores. Equal amounts are combined and hybridized to a microarray containing DNA or oligonucleotide probes representing small sections of chromosomes. This holistic approach allows the rapid screening of the entire genome while also enabling the investigation of changes in sequence of a particular section of a chromosome.
In addition, single nucleotide polymorphism (SNP), variation at a single nucleotide in a genome, can also be examined on a CGH+SNP array. A CGH+SNP array enables detection of genomic aberrations associated with copy number variations, but in addition, it can also detect copy neutral aberrations, such as loss of heterozygosity (LOH) and uniparental disomy (UPD), on the same array.
The main objective of this study was to demonstrate the superior labeling capability of the CYTAG™ TotalCGH Labeling Kit in preparing and labeling DNA for a CGH+SNP microarray, and further, to analyze the chip on the Innopsys InnoScan® 910.

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Retrieved Text: BioNumerics uses proven technology acquired from the Kodon software to bring various specialized genome comparison and analysis functions. The Genome Analysis Tools module offers side-by-side comparison of genomes and chromosomes, genome annotation, analysis of organization and functional behavior of genomes, alignment of multiple chromosomes and chromosome-based SNP analysis.
The Genome Analysis Tools module provides metagenomics tools for characterizing microbial communities based on deep sequencing of a taxonomical marker gene.
This module can only be used in combination with the Sequence Data module.
BioNumerics lets you align and compare sequences of up to full chromosome length. Discontinuous alignments are calculated using seed and stretch-based sequence mapping, revealing genomic inversions, swaps, duplications, insertions and deletions. Mutation and SNP discovery can be performed on template-based multiple chromosome alignments, with optional selection of mutation type (intergenic, synonymous, non-synonymous or indel) and filtering of significant SNPs based on quality scores. dNdS analysis based on the ratio synonymous/non-synonymous mutations within gene clusters is available to predict evolutionary selection pressure on genes.

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Retrieved Text: The Comprehensive Vision Loss Panel includes 250 genes with four subpanels: the Retinal Disease Subpanel (154 genes), the Albinism, Hermansky-Pudlak Syndrome and Waardenburg Syndrome Subpanel (18 genes), the Developmental Eye Subpanel (21 genes), and the Stickler and Cataract Subpanel (41 genes). Targeted familial testing is also available.
If indicated, Sanger sequencing may be performed in both directions using BigDye Terminator chemistry with the ABI 3730 DNA analyzer with target specific amplicons. It may also be used to supplement specific guaranteed target regions that fail NGS sequencing or as a confirmatory method for NGS positive results. NGS technology may not detect all small insertions or deletions. Additionally, it is not diagnostic for large duplications or deletions, repeat expansions, and structural genomic variation. Therefore, oligonucleotide array comparative genomic hybridization (aCGH) is available for this test for deletion/duplication analysis. The customized oligonucleotide microarray is a highly-targeted, exon-focused array capable of detecting microdeletions and microduplications at a much higher resolution than traditional aCGH methods. The sensitivity of the aCGH assay is estimated to be greater than 99% for medically-relevant microdeletions and microduplications in the exonic regions of 249 genes. Copy number variation of RAB28 will not be reported using aCGH.

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Retrieved Text: Am J Hum Genet. 2012 Sep 7;91(3):489-501. doi: 10.1016/j.ajhg.2012.08.003. Epub 2012 Aug 30.
Soemedi R1, Wilson IJ, Bentham J, Darlay R, Töpf A, Zelenika D, Cosgrove C, Setchfield K, Thornborough C, Granados-Riveron J, Blue GM, Breckpot J, Hellens S, Zwolinkski S, Glen E, Mamasoula C, Rahman TJ, Hall D, Rauch A, Devriendt K, Gewillig M, O' Sullivan J, Winlaw DS, Bu'Lock F, Brook JD, Bhattacharya S, Lathrop M, Santibanez-Koref M, Cordell HJ, Goodship JA, Keavney BD.
Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne NE1 3BZ, UK.
Previous studies have shown that copy-number variants (CNVs) contribute to the risk of complex developmental phenotypes. However, the contribution of global CNV burden to the risk of sporadic congenital heart disease (CHD) remains incompletely defined. We generated genome-wide CNV data by using Illumina 660W-Quad SNP arrays in 2,256 individuals with CHD, 283 trio CHD-affected families, and 1,538 controls. We found association of rare genic deletions with CHD risk (odds ratio [OR] = 1.8, p = 0.0008). Rare deletions in study participants with CHD had higher gene content (p = 0.001) with higher haploinsufficiency scores (p = 0.03) than they did in controls, and they were enriched with Wnt-signaling genes (p = 1 × 10(-5)). Recurrent 15q11.2 deletions were associated with CHD risk (OR = 8.2, p = 0.02). Rare de novo CNVs were observed in ~5% of CHD trios; 10 out of 11 occurred on the paternally transmitted chromosome (p = 0.01). Some of the rare de novo CNVs spanned genes known to be involved in heart development (e.g., HAND2 and

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Retrieved Text: Folliculin (GENBANK accession #BC015687) was mapped to the BHD locus by a genome wide linkage analysis using polymorphic microsatellite markers in a large Swedish family with BHD Syndrome. This study found evidence of linkage to 17p12-q11.2 (Khoo et al., 2001). Subsequent haplotype analysis defined a candidate interval between the two flanking markers, D17S1791 and D17S798 (Khoo et al., 2001).
Schmidt et al. (2001) performed a genome wide scan in a large BHD kindred (172 members) and localised the gene to the pericentromeric region of 17p using linkage analysis. Two-point linkage analysis of eight additional families with BHD syndrome produced a maximum LOD score of 16.06 at D17S2196. Haplotype analysis identified critical recombinants and defined the minimal region of non-recombination as being within an interval of less than four cM between D17S1857 and D17S805 on chromosome 17p11.2.
The FLCN gene was ultimately identified when Nickerson et al. (2002) narrowed the critical region for the BHD locus to a 700-kb segment on 17p11.2. This genomic region contains a number of unstable low-copy number repeat elements which are subject to aberrant recombination events, causing deletions and duplications of the region (Stankiewicz and Lupski, 2002). Deletions within this region cause Smith-Magenis Syndrome (SMS) (Lucas et al., 2002), while duplications cause Charcot-Marie-Tooth Syndrome 1A (Roa et al., 1991). Interestingly, while the FLCN gene is often heterozygously deleted in SMS, patients do not seem to develop any of the symptoms of BHD (Truong et al., 2010). However, there has been one reported case of an SMS patient who suffered three pneumothoraces as a child

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Input Text: Answer the following question given this paragraph: 

Plastids are organelles in plant cells that may have various jobs. The main types of plastids are chloroplasts, chromoplasts, and leucoplasts.


Q: Chloroplasts, chromoplasts, and leucoplasts are all plastids, organelles found in what kind of cells?

 Choices:

- plant cells

- heart cells

- lung cells

- animal cells

A:

Target Text: plant cells

#### Retrieved Documents ####

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Retrieved Text: Plastids are found in plants and some algae. They are necessary for essential life processes, like photosynthesis and food storage. Read this lesson to learn about major types of plastids and what they do to sustain life.
Did you ever wonder how plants breathe, drink, eat, and grow? They carry out these functions just like us, yet in different ways. One category of specialized organelles that plants use in order to survive is plastids.
Plastids are double membrane-bound organelles found inside plants and some algae, which are primarily responsible for activities related to making and storing food. Many plastids are photosynthetic, but some are not.
The chloroplasts are probably the most-known of the plastids. These are responsible for photosynthesis. The chloroplast is filled with thylakoids, which is where photosynthesis occurs, and chlorophyll.
Chromoplasts are what the name describes, a place for the pigments to be stored and synthesized in the plant. These are found in flowering plants, fruits, and aging leaves. The chloroplasts actually convert over to chromoplasts. There are carotenoid pigments here that allow for the different colors you see in fruits and the fall leaves. One of the main reasons for these structures and the colors is to attract pollinators.
Gerontoplasts are basically chloroplasts that are going through the aging process. These are chloroplasts of the leaves that are beginning to convert into different organelles or are being re-purposed, since the leaf is no longer utilizing photosynthesis (such as in the fall months).
Leucoplasts are the non-pigmented organelles. Unlike the others we have talked about, leucoplasts have no color at

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Retrieved Text: There are two main groups of plastid, the chromoplasts and the leucoplasts are colorless plastids. Chromoplasts may be photosynthetically active, e.g. chloroplasts, pheoplasts, rhodoplasts and blue-green chromoplasts or may be without photosynthetic activity, e.g., carotenoids.
Chloroplasts. Most plastids contain the pigments chlorophyll a and b are called chloroplasts. They are found in green algae and higher plants.
Pheoplasts contain the pigment fucoxanthin, which can absorb light and transfer the energy of chlorophyll. Pheoplasts are brown in the color, and are found in brown algae, diatoms and dinoflagellats.
Rhodoplasts contains the pigment phycoerythrin, and are found in the Rhodophyceac (red-algae).
Blue-green chromoplasts contain the pigments phycocyanin, phycoerytherin, chloroplyll a and carotenoids. They are found in the blue-green algae (now included in the Cyanobacteria.
In photosynthetic activity contain carotenoids, but have no chlorophyll. The color of carrots and tomatoes is due to the pigment present in the chromoplasts.
Plastids without pigment are called leucoplasts. They are found in embryonic and sexual cells, and in regions of the plant not receiving light. Leucoplasts which function in the storage of starch are called amyloplasts. They are found in endosperm, storage tubers and cotyledons. Leucoplasts which store oil are called elaioplasts, and those storing proteins are called aleuroneplasts.
For more help in Types of Plastids please click the button below to submit your homework assignment.

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Retrieved Text: biol. Najsitiniji delići od kakvih su sagrađene biljke i životinje.
(Slang) A silly, witless person.
ETYM Old Fren. celle, from Latin cella; akin to celare to hide, and Eng. hell, helm, conceal. Related to Hall.
In biology, a discrete, membrane-bound portion of living matter, the smallest unit capable of an independent existence. All living organisms consist of one or more cells, with the exception of viruses. Bacteria, protozoa, and many other microorganisms consist of single cells, whereas a human is made up of billions of cells. Essential features of a cell are the membrane, which encloses it and restricts the flow of substances in and out; the jellylike material within, the cytoplasm; the ribosomes, which carry out protein synthesis; and the DNA, which forms the hereditary material.
A room where a prisoner is kept; SYN. jail cell, prison cell.
Small room is which a monk or nun lives; SYN. cubicle.
The basic structural and functional unit of all organisms; cells may exist as independent units of life (as in monads) or may form colonies or tissues as in higher plants and animals.
A device that delivers an electric current as the result of a chemical reaction; SYN. electric cell.
A small unit serving as the nucleus of a larger political movement; SYN. cadre.
Minute mass of protoplasm in cell.
General name for a cell organelle of plants that is enclosed by a double membrane and contains a series of internal membranes and vesicles. Plastids contain DNA and are produced by division of existing plastids. They can be classified into two main groups: the chromoplasts, which contain

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Retrieved Text: The biogenesis of chloroplasts and other plastids, including protein import mechanisms and regulation by the ubiquitin-proteasome system.
Plastids are a diverse family of plant organelles. The family includes chloroplasts – the organelles responsible for photosynthesis – as well as a range of non-photosynthetic variants such as starch-containing amyloplasts in seeds, tubers and roots, carotenoid-rich chromoplasts in flowers and fruits, and chloroplast-precursor organelles in dark-grown plants called etioplasts (Nat. Rev. Mol. Cell Biol. 2013, 14: 787-802). Most plastid proteins are encoded by the nuclear genome and synthesized in the cytosol as precursors with N-terminal targeting signals called transit peptides. Import of precursors into chloroplasts is mediated by the TOC and TIC (Translocon at the Outer/Inner envelope membrane of Chloroplasts) complexes (New Phytol. 2008, 179: 257-285). While much progress has been made in understanding how the import machinery works, substantial gaps remain in our knowledge; for example, the mechanisms underlying the regulation of import are poorly understood. Our research seeks to achieve a more complete understanding of chloroplast protein import mechanisms, using a full spectrum of molecular, cellular, genetic, and biochemical approaches. We have brought to bear the unique advantages offered by the model plant Arabidopsis thaliana (thale cress) as an experimental system in relation to plastid protein import research. More recently, having identified potential practical applications of our work, we have begun to also employ crop species as alternative models.
Our recent work revealed that plastid biogenesis is directly regulated by the ubiquitin-proteasome system (UPS), defining a new and fundamentally important area of biology (Trends Cell Biol. 2013, 23:

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Retrieved Text: 1. Indicate whether the following statements are True (T) or False (F).
2. Make a sketch of the human nerve cell. What function do nerve cells perform?
The function of a nerve cell is to transmit messages to the brain and also to take away messages from the brain to the receptor organs.
(a) Cytoplasm: It is a fluid that fills the cell and occurs between the plasma membrane and the nucleus. Cell organelles such as mitochondria, ribosomes, Golgi bodies, etc. are suspended in the cytoplasm. The cytoplasm helps in the exchange of materials between cell organelles.
(b) Nucleus of a cell: Nucleus is the master of the cell. It commands all the functioning of the cell. It is generally located in the center of the cell and is spherical in shape. A membrane called nuclear membrane separates it from cytoplasm. It contains the genetic material DNA and RNA in it. This porous membrane allows the transfer of material in the nucleus and cytoplasm. Nucleus contains a dense body called Nucleolus which actually contains Chromosomes, the genetic material.
4. Which part of the cell contains organelles?
Cytoplasm is the part of the cell that contains various organelles such as mitochondria, ribosomes, Golgi bodies, etc.
5. Make sketches of animal and plant cells. State three differences between them.
They are generally small in size. They are usually larger than animal cells.
Cell wall is absent. Cell wall is present.
Vacuoles are small in size. Vacuoles are larger in size.
No other animal cell possesses plastids except for the protozoan Euglena. Plastids are present.
6. State the difference between eukaryotes

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Retrieved Text: Are you looking for NCERT Class 8 Solution? Download NCERT Solution Class 8 Science Chapter 8 : Cell-Structure and Functions and prepare better for your examinations.
Question 1: Indicate whether the following statements are True (T) or False (F).
Question 2: Make a sketch of the human nerve cell. What function do nerve cells perform?
The function of a nerve cell is to transmit messages to the brain and also to take away messages from the brain to the receptor organs. Thus, it controls the working of different parts of the body.
Question 3: Write short notes on the following.
It is a fluid that fills the cell and occurs between the plasma membrane and the nucleus. Cell organelles such as mitochondria, ribosomes, Golgi bodies, etc. are suspended in the cytoplasm. The cytoplasm helps in the exchange of materials between cell organelles.
It is a double-layered membrane which separates the contents of the nucleus from the cytoplasm. The nuclear membrane has nuclear pores that allow the transfer of specific substances in and out of the nucleus.
It is a small spherical body that is not bound by any membrane.
These are thread-like structures that carry genes. Genes contain information necessary for the transfer of characteristics from the parents to the offspring. Thus, chromosomes play an important role in the inheritance of characteristics.
Question 4: Which part of the cell contains organelles?
Cytoplasm is the part of the cell that contains various organelles such as mitochondria, ribosomes, Golgi bodies, etc. Cytoplasm is a fluid that fills the cell and occurs between the plasma membrane and the nucleus.
Question

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Retrieved Text: Stromules are motile extensions of the plastid envelope membrane, whose roles are not fully understood. They are present on all plastid types but are more common and extensive on non-green plastids that are sparsely distributed within the cell. During tomato fruit ripening, chloroplasts in the mesocarp tissue differentiate into chromoplasts and undergo major shifts in morphology. In order to understand what factors regulate stromule formation, we analysed stromule biogenesis in tobacco hypocotyls and in two distinct plastid populations in tomato mesocarp. We show that increases in stromule length and frequency are correlated with chromoplast differentiation, but only in one plastid population where the plastids are larger and less numerous. We used tobacco hypocotyls to confirm that stromule length increases as plastids become further apart, suggesting that stromules optimise the plastid-cytoplasm contact area. Furthermore, we demonstrate that ectopic chloroplast components decrease stromule formation on tomato fruit chromoplasts, whereas preventing chloroplast development leads to increased numbers of stromules. Inhibition of fruit ripening has a dramatic impact on plastid and stromule morphology, underlining that plastid differentiation status, and not cell type, is a significant factor in determining the extent of plastid stromules. By modifying the plastid surface area, we propose that stromules enhance the specific metabolic activities of plastids.
This is an electronic version of an Article published in The Plant Journal, August 2004, Volume 39, pp. 655-667. Copyright 2004 Blackwell Publishing Ltd and The Society for Experimental Biology.

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Retrieved Text: Cells have complex membranous organelles for the compartmentalization and regulation of most intracellular processes. Organelle biogenesis and maintenance requires newly synthesized proteins, each of which needs to go from the ribosome translating its mRNA to the correct membrane for insertion or translocation to an organellar subcompartment. Decades of research have revealed how proteins are targeted to the correct organelle and translocated across one or more organelle membranes to the compartment where they function. The paradigm examples involve interactions between a peptide sequence in the protein, localization factors, and various membrane-embedded translocation machineries. Membrane translocation is either cotranslational or posttranslational depending on the protein and target organelle. Meanwhile, research in embryos, neurons and yeast revealed an alternative targeting mechanism in which the mRNA is localized and only then translated to synthesize the protein in the correct location. In these cases, the targeting information is encoded by cis-acting sequences in the mRNA (“Zipcodes”) that interact with localization factors and, in many cases, are transported by molecular motors on cytoskeletal filaments. Recently, evidence has been found for this “mRNA-based” mechanism in organelleproteintargeting to endoplasmic reticulum, mitochondria, and the photosynthetic membranes within chloroplasts. Here we review known and potential roles of mRNAlocalization in proteintargeting to and within organelles. This article is part of a Special Issue entitled: Protein Import and Quality Control in Mitochondria and Plastids.

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Retrieved Text: Plant cell structure is not included in all health science subjects (e.g. all courses in anatomy & physiology) but is is an important part of general biology. Basic cell biology is included in UK A-Level Biology and equivalent courses. It is also useful general knowledge for anyone working in life sciences. This page helps with the task: With the help of a diagram describe the structure of a plant cell.
Note: The diagram above is a general plant cell - so not a particular part of any specific plant. The labels in pink are links to pages of further information about the part of the plant cell indicated. The structures are not necessarily drawn to scale but in enough detail to aid recognition and to help students re-draw this diagram by hand to include in study notes or homework.
The structure of plant cells has similarities and differences compared with the structure of animal cells. The following table lists the parts of plant cells shown in the diagram above with brief notes about each of the structures types of organelles in plant cells.
Plant cells have cell walls - as compared with animal cells which do not have cell walls, and prokaryotic cells (bacteria) which do have cell walls but they are of a different construction than those of plant cells.
The main functions of plant cell walls are mechanical. Plant cell walls form part of a transport system called the apoplast system via which water and some solutes can pass through plant tissue via apoplastic pathways (along / through

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Retrieved Text: What is a plastid? What are characteristics shared by all the plastids studies today?
What is an epdiermis? How does the epidermis differ form the cells deeper within a plant organ like a fruit?
What role do plasmodesmata play in plant cells?
They serve as communication portals between neighboring plant cells, allowing the passage of small molecules between the two cells.
Compare and contrast chromoplasts and chloroplasts with respect to cell type, color and function.
Is an amyloplast more similar to a chloroplast or a chromoplast? Why?
Amyloplast is more similar to chloroplasts because like amyloplast, chloroplasts also store starch. Amyloplasts don't store pigments, like chromoplasts do.
describe two benefits of crystal formation in plants.
Describe the impact of hypotonic, isotonic and hypertonic solutions on plant cells. Which is most likely to lead to the death of a plant cell after prolonged exposure?
Hypotonic: causes water to flow into plant cells, creating turgor pressure.
Hypertonic: causes water to leave the cell and the protoplast to shrink away from the cell wall. Most likely to lead to cell death.
Isotonic: doesn't create a net movement of water so there is no change.
What type of Symbiosis does a mycorrhizae represent?
Explain the difference between hypogynous and epigynous flowers.
in hypogynous flowers the petals and sepals attach below the carpels. In epigynous flowers the petals and sepals attach above the carpels.
Sepals and petals are modified leaves. Describe the characteristic of each that are shared with leaves.
Sepals are similar to leaves in that they are green and look like mini-leaves. Petals and leaves are morphologically similar even though they have different functions.
A flower

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Retrieved Text: Pracovní listy k výuce najdete v pdf přílohách níže pod galerií obrázků.
Mitochondria and plastids are fundamental innovations of eukaryotic cells. How­ever, they underwent secondary reduction in some eukaryotes. Such cases include the hydrogenosomes and mitosomes of parasitic protists and non-photosynthetic plastids, which can be found in various algae and parasitic plants. Complete losses of semiautonomous organelles are rare, but not impossible, as has been demonstrated by the recent discovery of a first amitochondriate protist.

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Retrieved Text: The cell. 6. Cholorplasts. Atlas of plant and animal histology.
Chloroplasts are organelles found in plant cells.
Chloroplasts are composed of outer membrane, inner membrane, intermembrane space between them, inner space, referred as stroma, and membrane sacs, known as thylakoids, which are organized in stacks and localized in the stroma.
Chloroplasts carry out photosynthesis: transformation of the electromagnetic energy of the light into chemical bonds of organic molecules.
Photosynthesis is accomplished in two stages: a light-dependent part where light energy is used to synthesize ATP and NADPH, which happens in the thylakoidal membranes, and a light-independent part where carbon from CO2 is covalently linked to ribulose-1,5-bisphosphate, which happens in the stroma.
Chloroplasts are usually large organelles (1 to 10 µm) present in plant cells. A cell from a leaf may contain from 20 to 100 chloroplasts. The shape of chloroplasts is variable, from round to ellipsoid, or much more complex. Chloroplasts are members of the plastids family and contain DNA, around 250 genes derived from the prokaryotic ancestor (see endosymbiosis). These genes code for ribosomal RNA, transference RNA and messenger RNA. In the interior of the chloroplast, proteins needed for the growth and division, and for photosynthesis, are synthetized.
Chloroplasts of a photosynthetic parenchyma (A), and in cells of a stoma (B).
Chloroplasts are composed of outer membrane, inner membrane, intermembrane space between them, the inner space is known as stroma and contains many membrane sacs known as thylakoids, arranged in stacks.
Chloroplasts are made up of several compartments. In the periphery, there are an outer membrane, an inner membrane and an intermembrane space

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Retrieved Text: Living Science Solutions for Class 8 Science Chapter 8 Cell Structure And Functions are provided here with simple step-by-step explanations. These solutions for Cell Structure And Functions are extremely popular among class 8 students for Science Cell Structure And Functions Solutions come handy for quickly completing your homework and preparing for exams. All questions and answers from the Living Science Book of class 8 Science Chapter 8 are provided here for you for free. You will also love the ad-free experience on Meritnation’s Living Science Solutions. All Living Science Solutions for class 8 Science are prepared by experts and are 100% accurate.
Which of these is multicellular?
Multicellular means made of more than one cells. Mushroom is a multicellular organism. All the other organisms mentioned here, are unicellular.
The egg of a hen is a cell. It divides repeatedly and differentiates into various tissues to develop into a chicken.
Which of these is not present in an animal cell?
In an animal cell, chloroplasts are not present. Chloroplasts are present in green plants and serve as the sites of photosynthesis in plants.
Which of these is the control centre of the cell?
The control centre of the cell is nucleus. The nucleus contains chromosomes, which divide during cell division.
Which organelles are responsible for energy production in a cell?
Mitochondria is responsible for energy production in a cell.
Which of these is not stated by the cell theory?
(a) Cells are the basic structural units of living organisms.
(b) All cells are identical.
(c) New cells are formed due to division in old cells.
(d) The way an organism functions

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Retrieved Text: when the cork cells reach maturity and are dead they are only being used for structure, not any activity. The onion epidermal cells must be alive to perform their function.
Why are the epidermal onion cells and Elodia leaves appear different from each other?
How does the shape of the potato tuber cells differ from that of the onion epidermal cells? How are the shape and spacing advantageous to the plant organs where they are found?
Which cells are more similar in appearance to the tomato epidermal cells, the onion or the potato?
How are raphides different from plastids?
Rhapides are elongated, crystals that function in storage and protection.
Plastids create and store food and pigments and are membrane bound organelles.
What is the primary role of the cell wall? How can you use this information to explain the differences in the thickness of the cell walls seen in the various specimens?
Describe the role of plasmodesmatea? How do plasmodesmata impact the individuality of the cells?
Plasmodesmatas are holes in the cell wall between cells that allow cells to be interconneted. Plasmodesmatas cause cells to lose some of their individuality in turn for being able to function in a coordinated way with the other cells.

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Retrieved Text: Our natural world also utilizes the principle of form following function, especially in cell biology, and this will become clear as we explore eukaryotic cells ( [link]). Unlike prokaryotic cells, eukaryotic cells have: 1) a membrane-bound nucleus; 2) numerous membrane-bound organelles such as the endoplasmic reticulum, Golgi apparatus, chloroplasts, mitochondria, and others; and 3) several, rod-shaped chromosomes. Because a eukaryotic cell’s nucleus is surrounded by a membrane, it is often said to have a “true nucleus.” The word “organelle” means “little organ,” and, as already mentioned, organelles have specialized cellular functions, just as the organs of your body have specialized functions.
Like prokaryotes, eukaryotic cells have a plasma membrane ( [link]), a phospholipid bilayer with embedded proteins that separates the internal contents of the cell from its surrounding environment. A phospholipid is a lipid molecule with two fatty acid chains and a phosphate-containing group. The plasma membrane controls the passage of organic molecules, ions, water, and oxygen into and out of the cell. Wastes (such as carbon dioxide and ammonia) also leave the cell by passing through the plasma membrane.
The plasma membranes of cells that specialize in absorption are folded into fingerlike projections called microvilli (singular = microvillus); ( [link]). Such cells are typically found lining the small intestine, the organ that absorbs nutrients from digested food. This is an excellent example of form following function.
The cytoplasm is the entire region of a cell between the plasma membrane and the nuclear envelope (a structure to be discussed shortly). It is made up of organelles suspended in the

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Retrieved Text: Karl August Möbius was the German zoologist who took the credit for the usage of a diminutive or organ. Organula was the tern used by this zoologist for the cellular structure.
The term organelle is considered similar with the cell compartment based on the opinion of most cell biologists.
The cell biologists who choose the specific definition of cell organelles state that a term can only be applied on those which contain DNA.
The organelles which contain DNA include plastids which can be found on some protists, algae and plants. Almost all eukaryotes contain mitochondria.
There are several organisms which have the organelles without DNA. It can be found on the flagellum.
The structure of Eukaryotic cells is very complex. The lipid membranes enclose the interior compartments of the cells.
You can use the light microscope to scrutinize the large organelles on the eukaryotic cells. You will be able to observe the vacuoles and nucleus. Mitochondria are considered as the common organelle that can be found in most eukaryotic cells.
If you compare the Eukaryotic cells and prokaryotic cells, the latter ones are less complex. In the past, people believe that the internal organization of the prokaryotic cells was little. Find facts about cell wall here.
It is stated that some prokaryotes have the micro compartments based on the current research about this cell. The diameter of the compartment is around 100–200 nm. The shell of protein is seen as the enclosure of this sub cellular compartment. Get facts about cell membrane here.
Based on the report in 2006, bacteria have the membrane-bound magnetosomes. In

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Retrieved Text: Prepare to receive your Biology The Essentials 1st Test Bank in the next moment.
1. What does a pine tree, an octopus, and a bacterium have in common at the microscopic level?
A. Mathias Schleiden and Theodore Schwann.
3. Why are cells called “the fundamental unit of life”?
A. All known organisms have one or more cells.
B. Earliest life on Earth is hypothesized to have been single-celled.
C. Some cells are separate living entities that can survive individually.
D. Cells are the smallest unit of life that can function independently.
D. Mathias Schleiden and Theodore Schwann.
5. Which component of the cell theory argues against life on Earth evolving from inorganic molecules?
A. All organisms are made of one or more cells.
B. The cell is the fundamental unit of all life.
C. All cells come from preexisting cells.
D. Cells are small in size.
E. All cells are either prokaryotic or eukaryotic.
B. Mathias Schleiden and Theodore Schwann.
C. all organisms have DNA, all organisms are made of cells, and all cells produce proteins.
8. How do cells avoid surface area limitations?
E. a sugar molecule attached to a protein.
A. has a hydrophilic head that is repelled by water.
B. has hydrophilic tails that are repelled by water.
C. has a hydrophilic head that is attracted to water.
D. has a hydrophobic head that is repelled by water.
E. has hydrophobic tails that are attracted to water.
E. composed of phospholipid molecules.
D. hydrophilic and selectively permeable.
E. hydrophobic and selectively permeable.
A. has a cell wall with peptidoglycan.
B. is usually smaller than a prokaryotic cell.
C. does not have membrane-bound organelles.
A. Bacteria, Animalia, and Plantae.
B. Fungi, Protista, and Animalia.
C. Archaea,

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Retrieved Text: They are found in leaves and carry out photosynthesis and cellular respiration, along with other metabolic processes. With specialized organelles doing specific jobs, the accomplishments of a cell are really quite impressive. Label the axon, dendrites, cell body, nucleus, Schwann's cells, and nodes of Ranvier. It contains the genetic material i. The water rushes into the cell through osmosis. Cells communicate with one another and are responsible for transmitting information from one generation of cells to another.
It produces the membranes that surround the lysosomes. Vesicles; are much smaller than vacuoles and function in transport within and to the outside of the cell. This page has worksheets, articles, and activities to use when teaching students about the human body. More complex tracheids with valve-like perforations called characterise the gymnosperms. Ribosomes are the producers of our factory-like cell.
Individual cell parts can be colored, if desired, as part of the labeling process. The cytoskeleton is a network of filaments and tubules found throughout the cytoplasm of the cell. The composition of the plant cell wall differentiates it from the cell walls of other organisms. Chloroplasts of Green Algae Protista and Plants descendants of some Green Algae are thought to have originated by endosymbiosis of a prokaryotic alga similar to living Prochloron Prochlorobacteria. Like a suitcase is tagged for a destination, the vesicles are now marked for their future location within the cell before they are dispatched. Centrioles form the tail, which moves the sperm toward the ovum. The centrosomes is where microtubules are made.
Sugars produced by photosynthesis in chloroplasts

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Retrieved Text: | „.led to the evolution of modern eukaryotic cells with mitochondria and chloroplasts.
^ The aerobic endosymbiont evolved into mitochondria.
A 20.7 The endosymbiotic theory proposes that mitochondria and chloroplasts in eukaryotic cells arose from eubacteria. An original ancestral cell gave rise to prokaryotic and eukaryotic cells.
Chloroplasts and mitochondria are in many ways similar to bacteria. This resemblance is not superficial; indeed there is compelling evidence that these organelles evolved from eubacteria (see p. 000 in Chapter 2). The endosymbiotic theory (IFigure 20.7) proposes that mitochondria and chloroplasts were once free-living bacteria that became internal inhabitants (endosymbionts) of early eukaryotic cells. According to this theory, between 1 billion and 1.5 billion years ago, a large, anaerobic eukaryotic cell engulfed an aerobic eubacterium, one that possessed the enzymes necessary for oxidative phosphorylation. The eubacterium provided the formerly anaerobic cell with the capacity for oxidative phosphorylation and allowed it to produce more ATP for each organic molecule digested. With time, the endosymbiont became an integral part of the eukaryotic host cell, and its descendants evolved into present-day mitochondria. Sometime later, a similar relation arose between photosynthesizing eubacteria and eukaryotic cells, leading to the evolution of chloroplasts.
A great deal of evidence supports the idea that mitochondria and chloroplasts originated as eubacterial cells. Many modern, single-celled eukaryotes (protists) are hosts to endosymbiotic bacteria. Mitochondria and chloroplasts are similar in size to present-day eubacteria and possess their own DNA, which has many characteristics in common with eubacterial DNA. Mitochondria and chloroplasts possess ribosomes, some of which are similar in size and structure to

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Retrieved Text: Cutaway drawing of a eukaryotic cell. Encyclopædia Britannica, Inc.
Bacterial cells differ from animal cells and plant cells in several ways. One fundamental difference is that bacterial cells lack intracellular organelles, such as mitochondria, chloroplasts, and a nucleus, which are present in both animal cells and plant cells. Encyclopædia Britannica, Inc.
Eukaryotic cells contain membrane-bound organelles, including a clearly defined nucleus, mitochondria, chloroplasts (unique to plant cells), a Golgi apparatus, an endoplasmic reticulum, lysosomes, and peroxisomes. Encyclopædia Britannica, Inc.
The cell cycle is an ordered sequence of events that prepares a cell for the process of cell division. Encyclopædia Britannica, Inc.
meiosis; gameteGametes are formed through meiosis (reduction division). Encyclopædia Britannica, Inc.
…spindle, which is formed by centrioles (cylindrical cell structures). This climax in the events of fertilization creates a joint product known as the zygote, which contains all the factors essential for the development of a new individual.

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Retrieved Text: 2) All cells carry out life activities (require energy, grow, have a limited size). Function - Organelles are found here and substances like salts may be dissolved in the cytoplasm. 3. There are two types of ER: rough ER and smooth ER. BIO Lab: Cell Organelles Computer Lab. All cells, whether they are prokaryotic or eukaryotic, have some common features. which may be used to pull two cells in close contact, and perhaps to facilitate the transfer of genetic material. Every cell in your body contains organelles (structures that have specific functions). The nucleus, mitochondria and chloroplasts are all organelles. Within cells, organelles tend to cluster close to where they do their job. For instance, the TEM showed that mitochondria contained two membranes and.
All cells, whether they are prokaryotic or eukaryotic, have some common features that consists of a fluid portion called the cytosol and the organelles and other. Like our cells, bacteria cells have DNA and a plasma membrane. But bacteria There are two basic types of cells, prokaryotic cells and eukaryotic cells. They do not have a nucleus or other membrane-bound organelles. Most organelles are common to both animal and plant cells. However, plant cells also have features that animal cells do not have: a cell wall, a large central vacuole, Between these two layers is the intermembrane space.
You can do all this because you are made of cells — tiny units of life that are like There are two main types of cells, prokaryotic and eukaryotic. All cells have membranes (the building), DNA

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Retrieved Text: Plant cells like animal cells are eukaryotic, i.e. they contain membrane bound nuclei and cell organelles. A plant cell differs from an animal cell in having certain distinctive structures - cell wall, vacuoles, plasmodesmata and plastids. On the contrary, plant cells lack centrioles and intermediate filaments, which are present in animal cells. Despite these, plant and animal cells share several similarities in structure, parts and their roles.
Plant cells are classified into three types, based on the structure and function, viz. parenchyma, collenchyma and sclerenchyma. The parenchyma cells are living, thin-walled and undergo repeated cell division for growth of the plant. They are mostly present in the leaf epidermis, stem pith, root and fruit pulp. Mature collenchyma cells are living, and provide stretchable support to the plant. Lastly, sclerenchyma cells (e.g. fiber cells) are hard, non-living and give mechanical support to plants. Now, let us see the different parts of a plant cell with their significant roles.
Cell wall is the outermost tough and rigid layer, which comprises cellulose, hemicellulose, pectin and at other times, lignin. As expected, it remains connected with the cell walls of other cells. The prime functions of cell wall are protection, giving structural support and helping in the filter mechanism.
Cell membrane, also called plasma membrane, is present inside the cell wall and surrounds the cytoplasm. It connects the intracellular components (organelles and cytoplasm) with the extracellular environment, and helps in protection and transportation. The cell membrane is permeable to specific substances only.
Plasmodesma (plural plasmodesmata) is a small opening, which connects plant cells with

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Retrieved Text: The makeup and absorption of both pectin and protein elements of the cell wall of C. acer amount were, learned by Babylon et al. (2001). Just about all inhabitants of those species complex are, discovered to have breeding kinds assessed upon germination at a 1:1 ratio. One receptor (MT) decides breeding sort, and the MT allele is leading to MT (both Kasai and Chimera 1990; 2003). MIKC type MADS box genes very similar to all those crucial in property plant advancement were found from the C. strigose even littoral intricate; gene analysis improved when candida cells started out to build up to tangier and diminished after childbirth (Tanabe et al. 2005). Approximately one hundred forty species of happen to be clarified.
Samarium (Gr. Contrast little decoration) does occur because only cells which are profoundly separated in the bio region to shape a brief isthmus and 2 semi cells which can be curved before perspective however flattened, oblong, or elliptical in negative perspective. Walls could be eloquent or ornamented; spines usually maybe not found on cells. Rectal or occasionally more adrenal chloroplasts or some happen in each individual semi cell. Mating type are, involved by reproduction in Samarium termini, together with pairs of cells. Mating cells available in the isthmus, and the protoplasts that are appearing be the gametes. Their combination ends within the thick walled zygote’s creation, which can be, discovered along using all the cell partitions that were empty, included at the enveloping mucilage.
Significantly, more than 1,000 species are, clarified, yet this genus does not produce

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Retrieved Text: This site provides a portal to access resources being developed through funding by the NSF Plant Genome Program (grant IOS-1339130; June 2014-June 2018). The broad goal of the project is to elucidate the biogenesis, differentiation, and environmental adaptation of chloroplasts. Chloroplasts are sub-cellular organelles in plants and algae that house the machinery for photosynthesis and numerous other essential metabolic processes. Chloroplasts are dynamic organelles that acquire different forms and functions in different cell types, and that adapt rapidly to changes in the environment.
We use maize as the experimental organism because it is a C4 plant with dimorphic chloroplasts, it offers a rich collection of chloroplast biogenesis mutants, and the maize leaf blade is an excellent experimental system for describing the developmental progression through which meristematic cells differentiate into photosynthetically-competent leaf cells.
a gene identification service for putative Mu-tagged alleles from other groups; click here to request this service.
The POGs2 Database, which facilitates cross-species functional inferences by displaying key functional attributes of orthologous proteins in maize, Arabidopsis, rice, and poplar.
A laboratory course for University of Oregon undergraduates that will be integrated with the large-scale identification of mutations underlying defects in chloroplast biogenesis.
An outreach program in St. Louis that will engage secondary school students in hands-on analysis of photosynthetic mutants in foxtail millet.

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Retrieved Text: Find Deals on Chloroplast Boards in Office Supplies on Amazon.
What is the importance of chloroplast to the cell?
Chloroplasts are important because if there were no chloroplasts, plants would not produce oxygen, sugars and starches which other animals use and eat.
An important feature of these chloroplasts is that their chloroplast DNA is highly reduced and fragmented into many small circles. Most of the genome has migrated to the nucleus, and only critical photosynthesis-related genes remain in the chloroplast.
Chloroplast. Chloroplasts are organelles — specialized parts of a cell that function in an organ-like fashion. They are found in vascular plants, mosses, liverworts, and algae. Chloroplast organelles are responsible for photosynthesis, the process by which sunlight is absorbed and converted into fixed chemical energy in the form of simple sugars synthesized from carbon dioxide and water.
it is important to achuchu.

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Retrieved Text: Which organelles have their own DNA and protein. What organelle contains its own DNA and ribosomes. Mitochondria because it's a separate bateria that somehow merged with the cell's in a mutualistic form. Their membrane proteins are made not by the ER, but by free ribosomes in the cytosol and by ribosomes contained within the mitochondria and chloroplasts themselves.
SummaryQuia Cell Organelles and Functions Copy this to my account E-mail to a friend Find other activities Match the cell organelle with the correct function.
Organelles are membrane-bound subunits within a cell -- analogous to organs in the body -- that perform specific functions. Match the cell organelle with the correct function. Which are the organelles in a cell that contain DNA. The plant would gain energy in the form of ATP, while the bacteria it's thought that chloroplasts were once cyanobacteria gains a safe environment with ample light for it to live. In plant cells, mitochondria and chloroplast have their own DNA and ribosomes. To do this on most router models you have to press the reset button of the router for appr.
It is this DNA that programs the synthesis of the proteins made on the. All lifeform have it's own DNA in order to reproduce. Follow the instructions on the screen to install E-DiagTools. The nucleus is the control center of the cell, and houses genetic information. A molecule of deoxyribonucleic acid DNA consists of a long series of sugar nucleotide. HDR captures the scene and subject as we see it.

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Retrieved Text: Abstract: Chlororespiration is a respiratory process located in chloroplast thylakoids which consists in an electron transport chain from NAD(P)H to oxygen. This respiratory chain involves the NAD(P)H dehydrogenase complex, the plastoquinone pool and the plastid terminal oxidase (PTOX), and it probably acts as a safety valve to prevent the over-reduction of the photosynthetic machinery in stress conditions. The existence of a similar respiratory activity in non-photosynthetic plastids has been less studied. Recently, it has been reported that tomato fruit chromoplasts present an oxygen consumption activity linked to ATP synthesis. Etioplasts and amyloplasts contain several electron carriers and some subunits of the ATP synthase, so they could harbor a similar respiratory process. This review provides an update on the study about respiratory processes in chromoplasts, identifying the major gaps that need to be addressed in future research. It also reviews the proteomic data of etioplasts and amyloplasts, which suggest the presence of a respiratory electron transport chain in these plastids.

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Retrieved Text: Organisms are composed of cells, and these cells have specific structures within in them that allow them to carry out their functions. These structures are called Organelles. The fine detail of the cell (which may be revealed by an electron microscope) is called the cell's ultrastructure. Organelles perform different functions within a cell, and this is called the Division of Labour.
The Nucleus is the largest organelle in a cell. It contains a dense structure called the Nucleolus and is surrounded by the Nuclear Envelope, a structure composed of two membranes, seperated by fluid, which contain a number of nuclear pores that can allow relatively large molecules through. The nucleus contains nearly all of the cell's genetic material. The Nucleolus creates Ribonucleic Acid and Ribosomes, which then travel out of the nucleus, through the nuclear pores, to the cytoplasm where they are involced in Protein Synthesis.
The Endoplasmic Reticulum (ER) is found near the Nucleas and is made up of a number of flattened sacs called Cisternae, which are continuous with the Nuclear Envelope. The Rough Endoplasmic Reticulum is called so because it has a lot of Ribosomes on its outer surface. The Smooth Endoplasmic Reticulum however, does not have Ribosomes. The Rough transports proteins that are synthesised in the Ribosomes, and the Smooth synthesises Lipids.
The Golgi Apparatus is a stack of membrane bound flattened sacs, and are responsible for the modification of proteins received from the ER. These proteins are then transported in vesicles around the cell.
Lysosomes are membrane bound spherical sacs which contain digestive enzymes used

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Retrieved Text: Learn vocabulary games, terms, , more mitochondria with coloring flashcards, other study tools. Chloroplasts Mitochondria Plant cells some Algae contain an organelle called the chloroplast. Put a check in the appropriate column( s) to indicate whether the following organelles are found in plant cells animal cells both. Use the organelles listed in the word bank. Coloring the Animal Cell Directions: Choose a color for each of the parts below and fill in the square with the color coloring of your choice. Acidophilus milk - Milk to which Lactobacillus acidophilus bacteria sheet have been added to aid in the digestion of lactose ( milk sugar). A chemical formula is a way of expressing information about the proportions of mitochondria atoms that constitute a particular chemical compound using a single line of chemical element symbols numbers. Organelle Color Organelle mitochondria Color Cell Membrane Ribosome Cytoplasm Smooth ER Rough ER Golgi Apparatus ( Body) Mitochondria Nucleolus Lysosome. Link Dwonload Chloroplast mitochondria Mitochondria mitochondria Coloring Worksheet Answer Key Pdf, Where I can Download Chloroplast , Read File Chloroplast , MOBI file of Chloroplast , Mitochondria Coloring Worksheet Answer Key, Mitochondria Coloring Worksheet Answer Key pdf live, Mitochondria Coloring Worksheet Answer Key Free Download File Chloroplast.
The chloroplast allows plants to harvest. Full page fax print Author: Owner. Specialized pigments in the chloroplast ( including the common green. sheet Mitochondria Zooxanthellae Plant Animal Cells Summary Students will begin the unit by finding out what the mitochondria differences are between coloring plant animal cells. Stewart' s Biology Class. Color Coded Cells Read the

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Retrieved Text: Re: How can anthocyanins be seperated from the solution of pigment extracted ?
Anthocyanins are in plant vacuoles not in plastids such as chromoplasts.
using paper chromatography and thin-layer chromatography.
science literature as in the two websites cited.

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======= Instance Index 5865 =========
Input Text: Answer the following question given this paragraph: 

A mitotic spindle forms from the centrioles and passes through the nuclear membrane, which remains intact. Chromosomes attach to the mitotic spindle, which separates the chromosomes and elongates the cell.


Q: A mitotic spindle forms from the centrioles and passes through the nuclear membrane, which remains intact. chromosomes attach to the mitotic spindle, which separates the chromosomes and does what?

 Choices:

- manipulates the cell

- elongates the cell

- destroys the cell

- migrates the cell

A:

Target Text: elongates the cell

#### Retrieved Documents ####

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Retrieved Text: Prokaryotes such as bacteria propagate by binary fission. For unicellular organisms, cell division is the only method to produce new individuals. In both prokaryotic and eukaryotic cells, the outcome of cell reproduction is a pair of daughter cells that are genetically identical to the parent cell. In unicellular organisms, daughter cells are individuals.
To achieve the outcome of identical daughter cells, some steps are essential. The genomic DNA must be replicated and then allocated into the daughter cells; the cytoplasmic contents must also be divided to give both new cells the machinery to sustain life. In bacterial cells, the genome consists of a single, circular DNA chromosome; therefore, the process of cell division is simplified. Mitosis is unnecessary because there is no nucleus or multiple chromosomes. This type of cell division is called binary fission.
The cell division process of prokaryotes, called binary fission, is a less complicated and much quicker process than cell division in eukaryotes. Because of the speed of bacterial cell division, populations of bacteria can grow very rapidly. The single, circular DNA chromosome of bacteria is not enclosed in a nucleus, but instead occupies a specific location, the nucleoid, within the cell. As in eukaryotes, the DNA of the nucleoid is associated with proteins that aid in packaging the molecule into a compact size. The packing proteins of bacteria are, however, related to some of the proteins involved in the chromosome compaction of eukaryotes.
The starting point of replication, the origin, is close to the binding site of the chromosome to the plasma membrane (Figure

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Retrieved Text: A cell moves through a series of phases in an orderly manner. During interphase, G 1 involves cell growth and protein synthesis, the S phase involves DNA replication and the replication of the centrosome, and G 2 involves further growth and protein synthesis. The mitotic phase follows interphase. Mitosis is nuclear division during which duplicated chromosomes are segregated and distributed into daughter nuclei. Usually the cell will divide after mitosis in a process called cytokinesis in which the cytoplasm is divided and two daughter cells are formed.
During interphase, the cell undergoes normal processes while also preparing for cell division. For a cell to move from interphase to the mitotic phase, many internal and external conditions must be met. The three stages of interphase are called G 1 , S, and G 2 .
The first stage of interphase is called the G 1 phase , or first gap, because little change is visible. However, during the G 1 stage, the cell is quite active at the biochemical level. The cell is accumulating the building blocks of chromosomal DNA and the associated proteins, as well as accumulating enough energy reserves to complete the task of replicating each chromosome in the nucleus.
Throughout interphase, nuclear DNA remains in a semi-condensed chromatin configuration. In the S phase (synthesis phase), DNA replication results in the formation of two identical copies of each chromosome—sister chromatids—that are firmly attached at the centromere region. At this stage, each chromosome is made of two sister chromatids and is a duplicated chromosome. The centrosome is duplicated during

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Retrieved Text: 1. a pin tapered at one end or both ends, or something with this shape.
2. the thin, tapering figure occurring during metaphase of cell division, composed of microtubules radiating from the centrioles and connecting to the chromosomes at their centromeres. Called also mitotic spindle.
mitotic spindle spindle (def. 2).
muscle spindle a mechanoreceptor found between the skeletal muscle fibers; the muscle spindles are arranged in parallel with muscle fibers, and respond to passive stretch of the muscle but cease to discharge if the muscle contracts isotonically, thus signaling muscle length. The muscle spindle is the receptor responsible for the stretch or myotatic reflex.
sleep s's bursts of activity of a particular waveform in the electroencephalogram in light or early sleep.
A sensory receptor in a muscle that responds to the stretching of tissue. Also called stretch receptor.
a specialized proprioceptive sensory organ composed of a bundle of fine striated intrafusal muscle fibers innervated by gamma nerve fibers. Their nuclei are gathered together near the center of each fiber to form a nuclear sac, which is surrounded in turn by sensory, annulospiral nerve endings, all enclosed in a fibrous sheath.
a PROPRIOCEPTOR found in skeletal muscle in the form of a capsule containing specialized muscle cells and nerve endings. Change in length or tension of muscle cells stimulates the spindle.
1. mitotic spindle; the fusiform figure occurring during metaphase of cell division, composed of microtubules radiating from the centrioles and connecting to the chromosomes at their centromeres.
a mechanoreceptor found within a skeletal muscle; the muscle spindles are arranged in parallel with muscle fibers. They

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Retrieved Text: Mitotic cyclin-dependent kinase with their cyclin partners (cyclin:Cdks) are the master regulators of cell cycle progression responsible for regulating a host of activities during mitosis. Nuclear mitotic events, including chromosome condensation and segregation have been directly linked to Cdk activity. However, the regulation and timing of cytoplasmic mitotic events by cyclin:Cdks is poorly understood. In order to examine these mitotic cytoplasmic events, we looked at the dramatic changes in the endoplasmic reticulum (ER) during mitosis in the early Drosophila embryo. The dynamic changes of the ER can be arrested in an interphase state by inhibition of either DNA or protein synthesis. Here we show that this block can be alleviated by micro-injection of Cyclin A (CycA) in which defined mitotic ER clusters gathered at the spindle poles. Conversely, micro-injection of Cyclin B (CycB) did not affect spatial reorganization of the ER, suggesting CycA possesses the ability to initiate mitotic ER events in the cytoplasm. Additionally, RNAi-mediated simultaneous inhibition of all 3 mitotic cyclins (A, B and B3) blocked spatial reorganization of the ER. Our results suggest that mitotic ER reorganization events rely on CycA and that control and timing of nuclear and cytoplasmic events during mitosis may be defined by release of CycA from the nucleus as a consequence of breakdown of the nuclear envelope.
Funding: Funding provided by National Institute of Health, Minority Biomedical Research Support (MBRS) R25-GM059298Z, BMJ, ASE, Genentech Foundation MS Dissertation Scholarship, grant #3179555, JDM, National Institute of Health, Support of Competitive Research (SCORE) Program, 5SC2 GM098229-02, BR, ZJB, AQS. The funders had

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Retrieved Text: The cell. 7. Microtubules. Atlas of plant and animal histology.
Microtubules are a component of the cytoskeleton, made up of many dimers of α- and β- tubulin proteins.
Microtubules are polarized filaments where polymerization and depolymerization of the microtubule alternatively occur, process known as dynamic instability.
Microtubules are mainly nucleated by protein complexes known as γ-tubulin rings.
In the animal cells, γ-tubulin rings are located in the pericentriolar material of the centrosome. In plant, they can be found at different locations of the cell.
Microtubules are involved in a number of cellular functions such as intracellular organization of the cytoplasm and the cell division. These jobs are done with the help of motor proteins: dyneins and kinesins.
Cilia and flagella have microtubules for structural support and movement (helped by motor proteins).
Microtubules are a component of the cytoskeleton involved in the organization of the eukaryotic cell cytoplasm. They carry out many functions, such as the spatial organization of organelles, work as tracks for vesicular trafficking, are needed for cell division since they form the mitotic spindle, help with the cell movement, and are the skeleton of cilia and flagella.
Organization of microtubules in an animal cell in culture.
Microtubules are long and relatively stiff tubules. Their wall is made up of many dimers of globular proteins: α- and β-tubulin, which are lined up in long rows known as protofilaments. Within a protofilament, there is no chemical bonds between adjoining tubulin dimers. A microtubule is usually composed of 13 protofilaments. α- and β-tubulin pairs are oriented in the same way, so that there is always α-tubulin

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Retrieved Text: The ability of all life to replicate itself for future generations originates in the reproduction of cells.
All cells arise from other cells.
Cells have a limited life span.
During cell division, one cell becomes split into 2 cells. The original cell is called the PARENT CELL. The 2 cells resulting from the division are called DAUGHTER CELLS.
– The cell cycle is the entire lifespan of a cell, starting with its production from a previous parent cell and ending with its division into 2 new daughter cells.
– Compared to the rest of the cells’ life, cell division is a brief and distinct stage in the cells’ life.
– The cell cycle is composed of an orderly sequence of phases that are controlled by the DNA of the cells’ nucleus.
– It is composed of an INTERPHASE where the cell is growing larger and replicating its DNA. Then there is nuclear division, called MITOSIS, that has 4 stages; prophase, metaphase, anaphase and telophase. Mitosis ends with the division of the cell into 2 separate daughter cells.
– Interphase is not part of cell division. It is a stage when the cell is growing, metabolizing and replicating its DNA.
– All cells spend most of their lives (about 90%) in Interphase. Some cells never leave the stage of interphase.
– Interphase provides enough time for the cell to grow large enough to eventually divide into 2 daughter cells.
– Interphase is divided into 3 stages; G1 phase, S phase and G2 phase.
– The cell experiences growth in volume and carries on its normal processes.
– If centrioles (small

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Retrieved Text: – Cell structure is correlated to cellular function.
How do we study cells?
1) Scanning electron microscopes focus a beam of electrons outs the surface of a specimen, providing images that look there dimensional.
Focus a beam of electrons through a specimen (TEMS), there kind of electron microscope is used to study the internal structure of cells.
– Ultra centrifuges fractional cells into their component parts.
– Biochemistry and cytology help correlate cell function with structure.
– Protests fungi, animals and plants all consist t of eukaryotic cells.
In the center of nucleus there is a concentrated region called the nucleolus and this is where ribosomal RNA is made and processed it’s also the site where there’s a lot of organization of other RNA protein complexes that have to be assembled in the nucleus.
And we see the endoplasm reticulum and outside of that is the Golgi and mitochondria and centrosome.
Centrosome is the region where doing cell division the chromosomal DNA comes together and we have also lysosomes, peroxisomes and in the outside of the cell we see microvilli protruding from the cell.
– The nucleus contains most of the cell’s genes and is usually the most consequence…. organelle.
– The nuclear membrane is a double membrane each membrane consists of a lipid bilayer.
– Pores regulate the entry and exit of molecules from the nucleus.
– The shape of the nucleus is maintained by the nuclear lamina which is composed of protein.
– Ribosome are particles made of ribosomal RNA and proteins.
The endomembrane system regulates protein traffic and performs metabolic functions in the cell.
The endomembrane system regulates protein

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Retrieved Text: most prominent structure inside of a cell.
DNA condensely wrapped around histone proteins. Humans have 46 chromosomes. Each one is made of two sister chromatids when they get replicated. There is a centromere connecting them.
All proteins involved in the cell cycle are encoded by two types of genes called the _____ genes and _____ genes.
coils upon itself into "super-coils"
small, circular auxiliary DNA supercoils that contain genes but are physically independent of the main coil.
are not part of the cells normal function, but are rather used to aid the cell adapt to abnormal conditions.
observed in all PK cells and are found within the cell. consist of RNA molecules and proteins in a Ribosomal complex. responsible for manufacturing proteins.
membrane bound compartment of a cell that contain enzymes or structures specialized for a particular fnc.
What separates life from non-life?
helps protect cell from changing osmotic pressures.
tough, fibrous layers taht surrounds the plasma membrance to protect and provide rigidity.
qualify as intermediate filaments which forms a dense mesh under the nuclear envelope to give shape and anchor chromosomes.
How do chromosomes take space in the nucleus?
Does the nucleus contain specific sites where gene products are processed?
What is the nuclear Envelope continuous with?
What are ribosomes of the ER associated with?
the synthesis of proteins that will be inserted into the plasma membrane.
What happens to most of the rER products?
What does the smooth ER also function for?
What does the Golgi Apparatus consist of?
What is the Golgi's polarity?
What is the function of the cis and trans portion of the Golgi?
normally products include H2O2 (hydrogen peroxide).
the plasma membrane of

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Retrieved Text: This article is about the cellular structure. For other uses, see Spindle (disambiguation).
In cell biology, the spindle apparatus (or mitotic spindle) refers to the cytoskeletal structure of eukaryotic cells that forms during cell division to separate sister chromatids between daughter cells. It is referred to as the mitotic spindle during mitosis, a process that produces genetically identical daughter cells, or the meiotic spindle during meiosis, a process that produces gametes with half the number of chromosomes of the parent cell.
Besides chromosomes, the spindle apparatus is composed of hundreds of proteins. Microtubules comprise the most abundant components of the machinery.
This diagram depicts the organization of a typical mitotic spindle found in animal cells. Chromosomes are attached to kinetochore microtubules via a multiprotein complex called the kinetochore. Polar microtubules interdigitate at the spindle midzone and push the spindle poles apart via motor proteins. Astral microtubules anchor the spindle poles to the cell membrane. Microtubule polymerization is nucleated at the microtubule organizing center.
Attachment of microtubules to chromosomes is mediated by kinetochores, which actively monitor spindle formation and prevent premature anaphase onset. Microtubule polymerization and depolymerization dynamic drive chromosome congression. Depolymerization of microtubules generates tension at kinetochores; bipolar attachment of sister kinetochores to microtubules emanating from opposite cell poles couples opposing tension forces, aligning chromosomes at the cell equator and poising them for segregation to daughter cells. Once every chromosome is bi-oriented, anaphase commences and cohesin, which couples sister chromatids, is severed, permitting the transit of the sister chromatids to opposite poles.
The cellular spindle apparatus includes the spindle microtubules, associated

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Retrieved Text: In cell division, the mitotic spindle self-assembles from nucleated microtubules and dynamic instability is used to find and capture chromosomes.
The basic mechanisms of spindle formation can be studied from first principles using simulations and in vitro work.
Cells typically have several degenerate mechanisms, including microtubule tension and spindle elongation, for achieving anaphase, where chromosomes are pulled apart into two identical sets.
This final lecture of the molecular machines topic is about the machinery of mitosis, the division of one cell into two identical daughter cells (Slide 1). The lecture builds on material presented in the previous lecture (‘Cellular machinery’) and describes how the mechanisms of mitosis are studied using simulations and in vitro.
The process of mitosis is divided into several descriptive stages, which are in general the same across different species and different cells. These are summarised in Slide 2.
Mitosis begins with prophase, where the nuclear DNA condenses from an essentially random polymer into distinct chromosomes. The DNA has been duplicated prior to cell division so there are two copies – so-called sister chromatids which are held together at a point known as the centromere. Microtubules nucleate at two centrosomes located on the outside of the nucleus. The polymerisation of overlapping microtubules between the centrosomes pushes them apart to form the mitotic spindle.
In prometaphase, the nuclear membrane disintegrates and microtubules emanating from the spindle poles attach to the centromere of each chromosome. For correct division, each chromosome requires one sister chromatid to be attached to each spindle pole. The resultant of the pulling forces from each pole causes

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Retrieved Text: Epstein-Barr Virus Nuclear Antigen 1 interacts with Regulator of Chromosome Condensation 1 dynamically throughout the cell cycle.
(Anglais) The Epstein-Barr virus (EBV) nuclear antigen 1 (EBNA1) is a sequence-specific DNA binding protein which plays an essential role in viral episome replication and segregation, by recruiting the cellular complex of DNA replication onto the origin (oriP) and by tethering the viral DNA onto the mitotic chromosomes. Whereas the mechanisms of viral DNA replication are well documented, those involved in tethering EBNA1 to the cellular chromatin are far from being understood. Here, we have identified Regulator of Chromosome Condensation 1 (RCC1) as a novel cellular partner for EBNA1. RCC1 is the major nuclear guanine nucleotide exchange factor (RanGEF) for the small GTPase Ran enzyme. RCC1, associated with chromatin, is involved in the formation of RanGTP gradients critical for nucleo-cytoplasmic transport, mitotic spindle formation, and nuclear envelope reassembly following mitosis. Using several approaches, we have demonstrated a direct interaction between these two proteins and found that the EBNA1 domains responsible for EBNA1 tethering to the mitotic chromosomes are also involved in the interaction with RCC1. The use of an EBNA1 peptide array confirmed the interaction of RCC1 with these regions and also the importance of the N-terminal region of RCC1 in this interaction. Finally, using confocal microscopy and FRET analysis to follow the dynamics of interaction between the two proteins throughout the cell cycle, we have demonstrated that EBNA1 and RCC1 closely associate on the chromosomes during metaphase, suggesting an essential role for the interaction during this phase, perhaps in

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Retrieved Text: Apicomplexans are unicellular protozoa that belong to kingdom Chromalveolata and the infrakingdom alveolata. Chromalveolates descended from a heterotrophic bikont (a bi-flagellated eukaryote), in which a secondary endosymbiotic event gave rise to a plastid-like organelle . Members of the alveolata are characterized by cortical alveoli (flattened vesicles located between the plasma membrane and a network of subpellicular microtubules), and micropore . They are further divided into phyla including ciliates, dinoflagellates, and apicomplexans, which differ mainly in their motile machinery [3, 4]. While ciliates and dinoflagellates move by means of cilia or flagella, invasive stage apicomplexans typically move by gliding motility. Additionally, many ciliates and dinoflagellates are free-living, while all apicomplexans are obligate parasites.
The phylum Apicomplexa encompasses numerous important disease-causing pathogens including the agents of malaria, toxoplasmosis, cryptosporidiosis, Texas and East Coast fever, and coccidiosis. The most widely studied of these are Plasmodium species, agents of malaria  and Toxoplasma gondii, which causes toxoplasmosis . Apicomplexans undergo asexual (vegetative) replication in order to cause acute infection (Fig. 1a, b). During asexual replication, Apicomplexa use distinct cell division schemes of fascinating complexity and variability to adapt to different hosts and suit specific intracellular niches . Both Plasmodium and Toxoplasma can also differentiate into gametes and undergo sexual recombination (Fig. 1d, e). In Toxoplasma, this occurs in the intestinal epithelium of cats and the resulting oocyst is shed in cat feces and sporulates in the environment. New infections are initiated by accidental ingestion of oocysts in contaminated food or water. Toxoplasma may also be transmitted by ingestion of infected animals

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Retrieved Text: A spindle poison, also known as a spindle toxin, is a poison that disrupts cell division by affecting the protein threads that connect the centromere regions of chromosomes, known as spindles. Spindle poisons effectively cease the production of new cells by interrupting the mitosis phase of cell division at the spindle assembly checkpoint (SAC). Unfortunately, spindle poisons, as numerous and varied as they are, still are yet to be 100% effective at ending the formation of tumors (neoplasms). Although not 100% effective, substantive therapeutic efficacy has been found in these types of chemotherapeutic treatments. The mitotic spindle is composed of microtubules (polymerized tubulin) that aid, along with regulatory proteins; each other in the activity of appropriately segregating replicated chromosomes. Certain compounds affecting the mitotic spindle have proven highly effective against solid tumors and hematological malignancies. Two specific families of antimitotic agents, vinca alkaloids and taxanes, interrupt the cell’s division by the agitation of microtubule dynamics. The vinca alkaloids work by causing the inhibition of the polymerization of tubulin into microtubules, resulting in the G2/M arrest within the cell cycle and eventually cell death. In contrast, the taxanes arrest the mitotic cell cycle by stabilizing microtubules against depolymerization. Even though numerous other spindle proteins exist that could be the target of novel chemotherapeutics, tubulin-binding agents are the only types in clinical use. Agents that affect the motor proteinkinesin are beginning to enter clinical trials. Another type, Paclitaxel, acts by attaching to tubulin within existing microtubules. Next, it stabilizes the polymer.
Normally, cells duplicate their genetic material and then

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Retrieved Text: Accurate chromosome segregation depends upon the precise coordination of mitotic events and on safeguard mechanisms, such as the spindle assembly and position checkpoints. We are interested in understanding the coordination of mitotic events; more specifically, how spindle orientation and cytokinesis are coordinated with chromosome segregation. We are also interested in substructures of the centrosome, named centrioles, which organize the formation of cilia in specialized cells.

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Retrieved Text: be passed on for the offspring to harness in their lifetime.
getting closer or further away.
what makes us unique. Nucleotides are situated in adjacent pairs in the double helix nature mentioned.
connected by three hydrogen bonds.
able to replicate the DNA to be passed on to offspring.
uncoil, the nucleotides are exposed so that the freely available nucleotides can pair up with them.
strands of DNA involved in replication, the first double helix produces 2 copies of itself via each strand.
used to make a protein.
A base called uracil replaces all thymine bases in mRNA.
The deoxyribose sugar in DNA in is replaced by ribose sugar in mRNA.
G-G-C-A-T-T, then the mRNA would be C-C-G-U-A-A (remember uracil replaces thymine).
mRNA moves out of the nucleus and away from the DNA towards the ribosomes.
assembled. The amino acids are assembled according to three nucleotide base sequences called CODONs.
Each codon codes for a specific amino acid.
amino acids to the site of protein synthesis on the ribosome.
originally proteins that were assembled from amino acids.
Chromosomes are DNA wrapped around proteins to form an Xshaped structure.
chromosomes (46 in humans) and are called DIPLOID (or 2n).
Chromosomes come in pairs, called Homologous Pairs (or homologs).
female. If a sperm cell containing a Y chromosome fertilizes an egg, the offspring will be male.
resulting egg or sperm has 24 instead of the normal 23.
composed of ribosomal RNA and is the site of protein synthesis within the cell.
centrioles are present in the cytoplasm at one end of the cell. Centrioles are not typically present in plant cells.
chromosome is doubled and consists of two chromatids, joined by a

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Retrieved Text: NCERT Solutions for Class 11 Biology Chapter 10 Cell Cycle and Cell Division free download in PDF for or to Study online without downloading files. Download Solutions of other subjects and study notes related to all chapters.
Specialised kind of cell division that reduces the chromosomes number by half, hence it is called reductional division.
Occurs during gametogenesis in plants and animals.
Involves two sequential cycles of nuclear and cell division called Meiosis I and Meiosis II.
It results in 4 haploid daughter cells.
Interphase occurs prior to meiosis which is similar to interphase of mitosis except the S phase is prolonged.
Format ion of gametes: In sexually reproducing organisms.
Genetic variability: Variations are very important for evolution.
Maintenance of chromosomal number: By reducing the chromosome number in gametes. Chromosomal number is restored by fertilisation of gametes.
Since the number of chromosomes in the parent and progeny cells is the same, it is called as equational division. Mitosis is divided into four sub stages.
Replicated chromosomes, each consisting of 2 chromatids, condense and become visible.
Microtubules are assembled into mitotic spindle.
Nucleolus and nuclear envelope disappear.
Centriole moves to opposite poles.
Spindle fibres attached to kinetochores (small disc-shaped structures at the surface of centromere) of chromosomes.
Chromosomes line up at the equator of the spindle to form metaphase plate.
Centromeres split and chromatids separate.
Chromatids move to opposite poles due to shortening of spindal fibres.
Chromosomes cluster at opposite poles.
Nuclear envelope assembles around chromosomes clusters’.
Nucleolus, Golgi Complex, E.R. reforms.
Maintenance of surface/volume ratio. Maintain Nucleo-cytoplasmic ratio.
Reproduction in unicellular organisms, lower plants and some insects.
Vegetative reproduction in plants takes place by mitosis.

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Retrieved Text: Spatial regulation of the spindle assembly checkpoint and anaphase-promoting complex in Aspergillus nidulans.
The spindle assembly checkpoint (SAC) plays a critical role in preventing mitotic errors by inhibiting anaphase until all kinetochores are correctly attached to spindle microtubules. In spite of the economic and medical importance of filamentous fungi, relatively little is known about the behavior of SAC proteins in these organisms. In our efforts to understand the role of gamma-tubulin in cell cycle regulation, we have created functional fluorescent protein fusions of four SAC proteins in Aspergillus nidulans, the homologs of Mad2, Mps1, Bub1/BubR1 and Bub3. Time-lapse imaging reveals that SAC proteins are in distinct compartments of the cell until early mitosis when they co-localize at the spindle pole body. SAC activity is, thus, spatially regulated in A. nidulans. Likewise, Cdc20, an activator of the anaphase-promoting complex/cyclosome, is excluded from interphase nuclei, but enters nuclei at mitotic onset and accumulates to a higher level in mitotic nuclei than in the surrounding nucleoplasm before leaving in anaphase/telophase. The activity of this critical cell cycle regulatory complex is likely regulated by the location of Cdc20. Finally, the gamma-tubulin mutation mipAD159 causes a nuclear-specific failure of nuclear localization of Mps1 and Bub1/R1 but not of Cdc20, Bub3 or Mad2.
Chromosome segregation in budding yeast: sister chromatid cohesion and related mechanisms.
Studies on budding yeast have exposed the highly conserved mechanisms by which duplicated chromosomes are evenly distributed to daughter cells at the metaphase-anaphase transition. The establishment of proteinaceous bridges between sister chromatids, a function provided by a ring-shaped complex known as

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Retrieved Text: How Do Cells Keep From Growing Too Large?
Cells keep from growing too large by undergoing cell division, also known as mitosis. The mitosis process involves a cell splitting off into two daughter cells that contain the same DNA as the original cell.
Mitosis occurs because the outside part of a cell cannot grow as fast as the inside part of the cell. The cell exterior is necessary for transporting oxygen and food to the cell interior. When a cell grows, the interior develops at a quicker rate than the exterior of the cell. As such, the interior develops to the point where the exterior of the cell can no longer transport food and oxygen at a sustainable rate. To remedy this, the cell undergoes mitosis to make the transport of nutrients more efficient through two smaller cells.
The beginning stage of mitosis is called prophase. In prophase, a cell's chromosomes condense and structures called centrioles begin to move in opposite directions within the cell. The next stage is metaphase, which results in the chromosomes forming a line within the middle of the cell.
After metaphase, the chromosomes are pulled apart by spindle fibers and pulled in opposite directions of the cell. The separated chromosomes are genetically identical and are referred to as chromatids. The final stage is telophase, which involves the formation of a nuclear envelope and the completion of two new cells containing the same DNA.

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Retrieved Text: A prokaryotic cell does not contain any true nucleus. This is why it is called a cell with a primitive type of nucleus. The term nucleotide fits nice in this case. Nuclear materials in a prokaryotic cell are not surrounded by any nuclear membrane. They are dispersed in its cytoplasm. Though the cell organelles such as mitochondria, plastids, endoplasmic reticule etc. are not found in a prokaryotic cell, ribosomes are present in it. Only the unwrapped DNA constitutes the chromosomal structure of a prokaryotic cell. For example, blue, green algae and bacteria are constituted of this type of cell.
In this type of cell, the nucleus is well structured that means nuclear materials are well organised and surrounded by a nuclear membrane. Chromosomes are organised with DNA, histone protein, and other components. From algae to higher flowering plants and from Amoeba to advanced animals, the basic structural and functional component is eukaryotic type of cell. Along with ribosome, other cell organelles are present in the cell.
On the basis of function, there are two other types of cells: somatic cell and gametic cell.
This type of cell takes part in the organization of the body of an organism. The cell divides through the process of binary fission and mitotic division. Organisms grow in this way. Moreover, cells take part in the organization of different organs and organ systems.
Gametal cells are produced in the organisms in which sexual reproduction and alternation of generations occur. Primordial germ cells divide through meiotic division and produce gametic cells. In a gametic cell, a

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Retrieved Text: Abstract : [en] Background Production of the GTP-bound form of the Ran GTPase (RanGTP) around chromosomes induces spindle assembly by activating nuclear localization signal (NLS)-containing proteins. Several NLS proteins have been identified as spindle assembly factors, but the complexity of the process led us to search for additional proteins with distinct roles in spindle assembly. Results We identify a chromatin-remodeling ATPase, CHD4, as a RanGTP-dependent microtubule (MT)-associated protein (MAP). MT binding occurs via the region containing an NLS and chromatin-binding domains. In Xenopus egg extracts and cultured cells, CHD4 largely dissociates from mitotic chromosomes and partially localizes to the spindle. Immunodepletion of CHD4 from egg extracts significantly reduces the quantity of MTs produced around chromatin and prevents spindle assembly. CHD4 RNAi in both HeLa and Drosophila S2 cells induces defects in spindle assembly and chromosome alignment in early mitosis, leading to chromosome missegregation. Further analysis in egg extracts and in HeLa cells reveals that CHD4 is a RanGTP-dependent MT stabilizer. Moreover, the CHD4-containing NuRD complex promotes organization of MTs into bipolar spindles in egg extracts. Importantly, this function of CHD4 is independent of chromatin remodeling. Conclusions Our results uncover a new role for CHD4 as a MAP required for MT stabilization and involved in generating spindle bipolarity. © 2013 Elsevier Ltd.

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Retrieved Text: Within 24 hours, a human cell can divide into two daughter cells that are identical to the original. This cell cycle includes growth of the cell, duplication of the DNA and division of the chromosomes and cell contents. The stages of the cycle -- which occur in both plants and animals -- are called interphase, mitosis and cytokinesis. Kinetochore and nonkinetochore -- also known as interpolar -- microtubules play an important role in the separation of chromosomes and the formation of daughter cells. These microscopic structures are both made from subunits called tubulin, but they have different functions during cell division.
When a cell enters mitosis, a microtubule-based structure called a spindle forms with two poles at either end of the enlarged cell. The chromosomes align along the center of the spindle prior to separation of the chromatids -- half of the duplicated chromosomes. Kinetochore microtubules extend from the spindle poles toward the center of the cell and attach to the chromatids at a structure called the kinetochore. The nonkinetochore microtubules also extend from the spindle toward the center of the cell, but they do not attach to the chromatids. Instead they overlap at the center of the spindle.
During late prophase -- one of the phases of mitosis -- the plate-like kinetochore forms on the duplicated chromosomes. Each chromosome has two kinetochores -- one for each identical sister chromatid -- attached to kinetochore microtubules from opposite poles. Kinetochore microtubules attached to the kinetochore cause the chromosomes to line up along the middle of the spindle. Nonkinetochore microtubules

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Retrieved Text: Cancer is uncontrolled cell growth in a certain area in the body that can spread. The way we treat cancer as of now is chemotherapy, or injecting radiation into the body to kill the extra cells. Chemotherapy is very dangerous and kills people all the time, but it is the only way we know of at the moment to treat cancer. When the cancer cell isn’t checked by polymerase and gets sent through and replicates, it makes more and more of the bad cells and is unable to be stopped. Cancer keeps going through the replication process making more cells than needed and unless treated soon, will kill you.
The G1 phase also known as the growth phase, is the first phase of the cell cycle. This phase is where cells and the contents of cells excluding chromosomes. Helicase is used here to unzip the double helix.
The next phase in the cell cycle is the S phase, this is where the chromosomes replicate and consist of two sister chromatids.Genes are located in chromosomes and DNA is found in the nucleus of a cell.
G2 phase is up next and this is where error check occurs for mutations and preparation of the cell for mitosis using DNA polymerase.Cancer skips this step and just keeps replicating without being checked.
Cell division begins with prophase where the chromosomes become visible as paired chromatids and the nuclear envelope disappears. The chromatin is at its least dense state.
The next phase of cell division is metaphase or the middle phase, this is where chromosomes become

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Retrieved Text: FEBS Lett. 2002 Apr 24;517(1-3):167-71.
Identification of casein kinase Ialpha interacting protein partners.
Dubois T1, Howell S, Zemlickova E, Aitken A.
Casein kinase Ialpha (CKIalpha) belongs to a family of serine/threonine protein kinases involved in membrane trafficking, RNA processing, mitotic spindle formation and cell cycle progression. In this report, we identified several CKIalpha interacting proteins including RCC1, high mobility group proteins 1 and 2 (HMG1, HMG2), Erf, centaurin-alpha1, synaptotagmin IX and CPI-17 that were isolated from brain as CKIalpha co-purifying proteins. Actin, importin-alpha(1), importin-beta, PP2Ac, centaurin-alpha1, and HMG1 were identified by affinity chromatography using a peptide column comprising residues 214-233 of CKIalpha. We have previously shown that centaurin-alpha1 represents a CKIalpha partner both in vitro and in vivo. The nuclear protein regulator of chromosome condensation 1 (RCC1) is a guanosine nucleotide exchange factor for Ran which is involved in nuclear transport and mitotic spindle formation. Here we show that CKIalpha and RCC1 interact in brain and in cultured cells. However, the interaction does not involve residues 217-233 of CKIalpha which are proposed from X-ray structures to represent an anchoring site for CKI partners. Formation of the RCC1/CKIalpha complex is consistent with the association of the kinase with mitotic spindles. In conclusion, we have identified a number of novel CKIalpha protein partners and their relations to CKI are discussed.

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Retrieved Text: Our natural world also utilizes the principle of form following function, especially in cell biology, and this will become clear as we explore eukaryotic cells ( [link]). Unlike prokaryotic cells, eukaryotic cells have: 1) a membrane-bound nucleus; 2) numerous membrane-bound organelles such as the endoplasmic reticulum, Golgi apparatus, chloroplasts, mitochondria, and others; and 3) several, rod-shaped chromosomes. Because a eukaryotic cell’s nucleus is surrounded by a membrane, it is often said to have a “true nucleus.” The word “organelle” means “little organ,” and, as already mentioned, organelles have specialized cellular functions, just as the organs of your body have specialized functions.
Like prokaryotes, eukaryotic cells have a plasma membrane ( [link]), a phospholipid bilayer with embedded proteins that separates the internal contents of the cell from its surrounding environment. A phospholipid is a lipid molecule with two fatty acid chains and a phosphate-containing group. The plasma membrane controls the passage of organic molecules, ions, water, and oxygen into and out of the cell. Wastes (such as carbon dioxide and ammonia) also leave the cell by passing through the plasma membrane.
The plasma membranes of cells that specialize in absorption are folded into fingerlike projections called microvilli (singular = microvillus); ( [link]). Such cells are typically found lining the small intestine, the organ that absorbs nutrients from digested food. This is an excellent example of form following function.
The cytoplasm is the entire region of a cell between the plasma membrane and the nuclear envelope (a structure to be discussed shortly). It is made up of organelles suspended in the

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Retrieved Text: In Eukaryotic Cells, Chromosomes Are Composed Of _____.
How is plant cell cytokinesis different from animal cell cytokinesis Plant cells deposit vesicles containing cell-wall building blocks on the metaphase plate; animal cells form a cleavage furrow.
The beginning of anaphase is indicated by which of the following? Cohesin is cleaved enzymatically.
What happens if MPF (mitosis-promoting factor) is introduced into immature frog oocytes that are arrested in G2? The cells enter mitosis.
Once a cell completes mitosis, molecular division triggers must be turned off. What happens to MPF during mitosis? The cyclin component of MPF is degraded.
Density-dependent inhibition is explained by which of the following? As cells become more numerous, the cell surface proteins of one cell contact the adjoining cells and they stop dividing.
A research team began a study of a cultured cell line. Their preliminary observations showed them that the cell line did not exhibit either density-dependent inhibition or anchorage dependence. What could they conclude right away? The cells show characteristics of tumors.
For a chemotherapeutic drug to be useful for treating cancer cells, which of the following is most desirable? It interferes with rapidly dividing cells.
Cells from advanced malignant tumors often have very abnormal chromosomes and an abnormal number of chromosomes. What might explain the association between malignant tumors and chromosomal abnormalities? Cell cycle checkpoints are not in place to stop cells with chromosome abnormalities.
Exposure of zebrafish nuclei to meiotic cytosol resulted in phosphorylation of NEP55 and L68 proteins by cyclin-dependent kinase 2. NEP55 is a protein of the inner nuclear membrane, and L68 is a protein of

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Retrieved Text: We have identified a maize homologue of yeast MAD2, an essential component in the spindle checkpoint pathway that ensures metaphase is complete before anaphase begins. Combined immunolocalization of MAD2 and a recently cloned maize CENPC homologue indicates that MAD2 localizes to an outer domain of the prometaphase kinetochore. MAD2 staining was primarily observed on mitotic kinetochores that lacked attached microtubules; i.e., at prometaphase or when the microtubules were depolymerized with oryzalin. In contrast, the loss of MAD2 staining in meiosis was not correlated with initial microtubule attachment but was correlated with a measure of tension: the distance between homologous or sister kinetochores (in meiosis I and II, respectively). Further, the tension-sensitive 3F3/2 phosphoepitope colocalized, and was lost concomitantly, with MAD2 staining at the meiotic kinetochore. The mechanism of spindle assembly (discussed here with respect to maize mitosis and meiosis) is likely to affect the relative contributions of attachment and tension. We support the idea that MAD2 is attachment-sensitive and that tension stabilizes microtubule attachments.
The spindle checkpoint is a surveillance pathway that ensures metaphase is complete before anaphase begins (Elledge, 1996; Rudner and Murray, 1996; Wells, 1996; Hardwick, 1998). The components of the spindle checkpoint were originally identified in budding yeast as nonessential genes that allowed cells to divide even in the absence of fully formed spindles. At least seven yeast genes have been identified in the pathway, including Bub1, 2, and 3, Mad1, 2, and 3, and Mps1 (Hardwick, 1998). One of the most thoroughly studied spindle checkpoint genes is Mad2, which encodes a highly conserved

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Retrieved Text: Delay in G2 – a rescue compartment?
Can giant cells repair DNA?
Mitotic death is a delayed response of p53 mutant tumours that are resistant to genotoxic damage. Questions surround why this response is so delayed and how its mechanisms serve a survival function. After uncoupling apoptosis from G1 and S phase arrests and adapting these checkpoints, p53 mutated tumour cells arrive at the G2 compartment where decisions regarding survival and death are made. Missed or insufficient DNA repair in G1 and S phases after severe genotoxic damage results in cells arriving in G2 with an accumulation of point mutations and chromosome breaks. Double strand breaks can be repaired by homologous recombination during G2 arrest. However, cells with excessive chromosome lesions either directly bypass the G2/M checkpoint, starting endocycles from G2 arrest, or are subsequently detected by the spindle checkpoint and present with the features of mitotic death. These complex features include apoptosis from metaphase and mitosis restitution, the latter of which can also facilitate transient endocycles, producing endopolyploid cells. The ability of cells to initiate endocycles during G2 arrest and mitosis restitution most likely reflects their similar molecular environments, with down-regulated mitosis promoting factor activity. Resulting endocycling cells have the ability to repair damaged DNA, and although mostly reproductively dead, in some cases give rise to mitotic progeny. We conclude that the features of mitotic death do not simply represent aberrations of dying cells but are indicative of a switch to amitotic modes of cell survival that may provide additional mechanisms of genotoxic resistance.
Following severe genotoxic damage,

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Retrieved Text: Spindle assembly during meiosis I in primary Drosophila spermatocytes.
Recording of GFP-alphaTubulin84B in primary Drosophila spermatocytes reveals the location of two diametrically opposed asters around the nuclear envelope before meiosis I. Upon nuclear envelope breakdown, indicated by the sudden entry of GFP signal into the nuclear area, spindle assembly takes place. Intranuclear microtubules form a bipolar structure that connect the asters at the two poles. Extranuclear microtubules derived from both asters expand toward the cortex and converge in the equatorial plane of the cell.
Recording of GFP-alphaTubulin84B in primary Drosophila spermatocytes reveals the behaviour of intra- and extranuclear microtubules during the first stages of spindle assembly. Later, at anaphase I, intranuclear microtubules contacting the chromosomes shorten, whereas extranuclear microtubules expand towards the cortex and converge at the position where the cytokinesis furrow will form.
Spindle assembly and chromosome behaviour during meiosis I in primary Drosophila spermatocytes.
Recording of GFP-alphaTubulin84B (in yellow) and Histone2-YFP (in red) reveal microtubule and chromosome behaviour during spindle assembly in meiosis I. During prometaphase I bivalent chromosomes interact with astral microtubules and congress to the metaphase I plate.
Recording of GFP-alphaTubulin84B (in yellow) and Histone2-YFP (in red) reveal microtubule and chromosome behaviour during spindle assembly and division in meiosis I. During anaphase I homolog chromosomes separate and migrate to opposite poles as kinetochore microtubules shorten.
Spindle assembly and central spindle formation during meiosis I in primary Drosophila spermatocytes.
Recording of GFP-alphaTubulin84B in a primary Drosophila spermatocyte from the onset of meiosis I to telophase I. The different sets of microtubules can be tracked all throughout the cell cycle. Note

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Retrieved Text: Mitosis is accompanied by dramatic changes in chromatin organization and nuclear architecture. Transcription halts globally and most sequence-specific transcription factors and co-factors are ejected from mitotic chromatin. How then does the cell maintain its transcriptional identity throughout the cell division cycle? It has become clear that not all traces of active transcription and gene repression are erased within mitotic chromatin. Many histone modifications are stable or only partially diminished throughout mitosis. In addition, some sequence-specific DNA binding factors have emerged that remain bound to select sites within mitotic chromatin, raising the possibility that they function to transmit regulatory information through the transcriptionally silent mitotic phase, a concept that has been termed “mitotic bookmarking.” Here we review recent approaches to studying potential bookmarking factors with regards to their mitotic partitioning, and summarize emerging ideas concerning the in vivo functions of mitotically bound nuclear factors.
Mitosis imposes dramatic and dynamic changes on nuclear organization and gene expression in eukaryotic cells. In metazoans, the nuclear envelope temporarily disintegrates, most nuclear structures are transiently dissolved or rearranged, and nuclear transcription by all three polymerases is globally arrested. Silencing of gene expression is accompanied by the separation of most transcriptional regulators from mitotic chromatin. Following chromosome segregation and re-formation of the nuclear envelope, bulk transcription resumes in the daughter cells that ultimately re-acquire gene expression patterns that are often similar to or indistinguishable from those of the mother cell. It has been widely assumed that these transitions present a problem for the cell’s maintenance of transcriptional identity, prompting investigations into mechanisms that

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Retrieved Text: In cell biology, the centrosome is an organelle that is the main place where cell microtubules are organized. Also, it regulates the cell division cycle, the stages which lead up to one cell dividing in two.
The centrosome was discovered by Edouard Van Beneden in 1883, and was described and named in 1888 by Theodor Boveri.
The centrosome has apparently only evolved in animal cells. Fungi and plants use other structures to organize their microtubules. Although the centrosome has a key role in efficient mitosis in animal cells, it is not necessary.
A centrosome is composed of two centrioles at right angles to each another. They are surrounded by a shapeless mass of protein.
The centrosome is copied only once per cell cycle. Each daughter cell inherits one centrosome, containing two centrioles. The centrosome replicates during the interphase of the cell cycle. During the prophase of mitosis, the centrosomes migrate to opposite poles of the cell. The mitotic spindle then forms between the two centrosomes. Upon division, each daughter cell receives one centrosome.
Centrosomes are not needed for the mitosis to happen. When the centrosomes are irradiated by a laser, mitosis proceeds with a normal spindle. In the absence of the centrosome, the microtubules of the spindle are focused to form a bipolar spindle. Many cells can completely undergo interphase without centrosomes.
Although centrosomes are not needed for mitosis or the survival of the cell, they are needed for survival of the organism. Cells without centrosomes lack certain microtubules. With centrosomes the cell division is much more accurate and efficient. Some cell

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Input Text: Answer the following question given this paragraph: 

Aldehydes, ketones, carboxylic acids, esters, and ethers h ave oxygencontaining functional groups.


Q: Aldehydes, ketones, carboxylic acids, esters, and ethers all have functional groups containing what element?

 Choices:

- oxygen

- silicon

- carbon

- methane

A:

Target Text: oxygen

#### Retrieved Documents ####

Rank: 0
Score: 104.74158
Retrieved Text: P. J. Kocienski, Protecting Groups, Georg Thieme Verlag, 1994 1. Hydroxyl groups 2 Ketones and aldehydes 3. Amines 4. Carboxylic Acids - Protect functional groups which may be incompatible with a set of reaction conditions - 2 step process- must be efficient - Selectivity a. selective protection b. selective deprotection Hydroxyl Protecting Groups Ethers Methyl ethers R-OH > R-OMe difficult... � Learn to recognize the carboxylic acid, ester, and related functional groups. � Learn the IUPAC system for naming carboxylic acids and esters. � Learn the important physical properties of the carboxylic acids and esters.
Amino acids have both an amine functional group and a carboxylic acid functional group in the same molecule and proteins are formed by linking the amine group from one molecule with the carboxylic acid group of another to form an amide bond.
� Learn to recognize the carboxylic acid, ester, and related functional groups. � Learn the IUPAC system for naming carboxylic acids and esters. � Learn the important physical properties of the carboxylic acids and esters.

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Rank: 1
Score: 78.376144
Retrieved Text: A variety of functional groups contain what is known as a carbonyl, which is a carbon atom double bonded to an oxygen atom. This video lesson focuses on ketones, aldehydes, and amides. Duration: 5:47.
This video lesson focuses on carboxylic acids and esters. Included is the synthesis of methyl salicylate, which is the chemical responsible for the smell of wintergreen. Duration: 7:56.

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Retrieved Text: This book leads the reader on a spirited journey of discovery through the structures, pathways, and reactions of organic compounds. While other books on organic chemistry cater mostly to premed students, this volume ties in the discussion to the entire discipline of chemistry. Throughout, it promotes critical thinking and encourages readers to question existing assumptions instead of focusing solely on applications.
Prologue and Introduction to Part I Background.
Chapter 1. An Introduction to Structure and Bonding.
A. The Sources of Carbon Compounds.
C. On the Nature of the Chemical Bond.
Chapter 2. An Introduction to Spectroscopy and Selected Spectroscopic Methods in Organic Chemistry.
Chapter 3. Structure: The Nomenclature of Hydrocarbons and the Shape of Things to Come.
C. Physical and Chemical Properties; Oxidation and Reduction of Hydrocarbons.
Chapter 4. An Introduction to Dynamics.
B. Review of Some Energy Considerations.
C. The Barrier Between Reactants and Products.
D. More About the Transition State.
E. Rotation About Sigma (s) Bonds in Acyclic Alkanes, Alkenes, Alkynes and Alkyl Substituted Arenes.
F. Conformational Analysis of Medium–Ring Cyclic Alkanes .
G. The Conservation of Symmetry During Reactions.
H. The Measurement of Chirality.
Chapter 5. Classes of Organic Compounds – A Survey. An Introduction to Solvents, Acids and Bases; Computational Chemistry.
B. General Characteristics of Functional Group Placement.
C. The Functional Groups and Their Names.
D. An Introduction to Solvents.
Introduction to Part II Middleground.
Chapter 6. Reactions of Hydrocarbons: Oxidation, Reduciton, Substitution, Addition, Elimination and Rearrangement.
E. Arenes and Aromaticity: Special Introduction.
Chapter 7. The Reactions of Alkl, Alkenyl and Aryl Halides: Oxidation Reduction, Substitution, Addition Elimination, and Rearrangement.
D. Reduction of Alkyl, Aldenyl and Aryl Halides.
G. Elimination Reactions of Alkyl and Alkenyl Halides.
H. Rearrangement

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Retrieved Text: Catalytic reductions are among the most used synthetic transformations, and the past 15 years or so have seen great progress in this field. This work covers the latest developments in catalytic hydrogenation/transfer hydrogenation methodology, as well as selective coverage of more well-established processes.
The two volumes include discussion of both heterogeneous and homogeneous catalytic systems, and enantioselective methodology is well represented. There is a focus on the use of metal nanoparticles, both in suspension as well as on solid supports. Furthermore, the advent of research on the conversion of renewable resources into fuels and chemicals has given a great impetus to the field, as deoxygenations are often the first step in the conversion of biomass and this can often be achieved using hydrogenation or hydrogenolysis reactions. The volumes are organized based on the type of functionality that is being reduced.
Volume 1 covers the hydrogenation of alkenes, arenes, hetarenes, alkynes, and allenes. In addition, there are chapters on the catalytic reduction of alcohols, hydrogenolysis of ethers, the reduction of carbonates and carbon dioxide, the reduction of peroxo compounds, reduction of sulfur compounds, and catalytic hydrodehalogenation reactions.
Volume 2 covers carbonyl group reductions, with contributions on the reduction of aldehydes, ketones, and carboxylic acids and derivatives. Volume 2 also includes a series of chapters on the catalytic reduction of nitrogen-containing functional groups such as imines (including the reductive amination of aldehydes and ketones), nitro and nitroso compounds, N-oxides, azides, and nitriles.

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Score: 73.679276
Retrieved Text: Interchange among carboxylic acid derivatives, such as amides, esters, acyl phosphates, and thioesters, is a major theme in biochemistry. This makes reactions of carboxylic acid derivatives a major theme for MCAT review.
Carboxylic acid derivatives include the carboxylates, amides, and esters. Also anhydrides, acyl halides, thioesters and acyl phosphates. Of the latter group, anhydrides and acyl halides don't appear in biochemistry, so while they are important for general organic chemistry, the new MCAT in not be so interested in them. However, thioesters and acyl phosphates do figure prominently in biochemistry. In fact, having a high free energy, the status of thioesters and acyl phosphates as the prototypical activated acyl compounds in biochemistry makes them among the most important types of organic molecules to understand.
Understand how resonance stabilization of the carboxylate anion promotes the acidity of carboxylic acids.
Understand the order of stability among carboxylic acid derivatives.
See nucleophilic acyl substitution mechanisms as recapitulations of a general mechanism involving formation and resolution of a tetrahedral intermediate: Acid Halide Formation, Fischer Esterification, Use of Carboxylate Anion Nucleophile to form Esters, Hydrolysis of Acid Halides, Reaction of Acyl Halide with Ammonia or Amine, Esterification of Acid Halides, Esterification of Acid Anhydrides, Saponification of Esters. Acyl substitution appears on many MCATs.
Understand the role acid catalysis plays in facilitating some acyl substitution mechanisms.
Be able to recognize and follow Claisen Condensation, Nitrile Hydrolysis, Nitrile Reduction or Hofmann Rearrangement if you were presented with the mechanism.
Review the basic terms for reactions of aldehydes & ketones using the question server. Complete the fundamental terms crossword puzzle. Here

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Score: 70.04978
Retrieved Text: Concepts: Hybridisation of carbon; Sigma and pi-bonds; Shapes of molecules; Structural and geometrical isomerism; Optical isomerism of compounds containing up to two asymmetric centers, (R,S and E,Z nomenclature excluded); IUPAC nomenclature of simple organic compounds (only hydrocarbons, mono-functional and bi-functional compounds); Conformations of ethane and butane (Newman projections); Resonance and hyperconjugation; Keto-enol tautomerism; Determination of empirical and molecular formula of simple compounds (only combustion method); Hydrogen bonds: definition and their effects on physical properties of alcohols and carboxylic acids; Inductive and resonance effects on acidity and basicity of organic acids and bases; Polarity and inductive effects in alkyl halides; Reactive intermediates produced during homolytic and heterolytic bond cleavage; Formation, structure and stability of carbocations, carbanions and free radicals.
Preparation, properties and reactions of alkanes: Homologous series, physical properties of alkanes (melting points, boiling points and density); Combustion and halogenation of alkanes; Preparation of alkanes by Wurtz reaction and decarboxylation reactions.
Preparation, properties and reactions of alkenes and alkynes: Physical properties of alkenes and alkynes (boiling points, density and dipole moments); Acidity of alkynes; Acid catalysed hydration of alkenes and alkynes (excluding the stereochemistry of addition and elimination); Reactions of alkenes with KMnO4 and ozone; Reduction of alkenes and alkynes; Preparation of alkenes and alkynes by elimination reactions; Electrophilic addition reactions of alkenes with X2, HX, HOX and H2O (X=halogen); Addition reactions of alkynes; Metal acetylides.
Reactions of benzene: Structure and aromaticity; Electrophilic substitution reactions: halogenation, nitration, sulphonation, Friedel-Crafts alkylation and acylation; Effect of o-, m- and p-directing groups in monosubstituted benzenes.
Phenols: Acidity, electrophilic substitution reactions (halogenation, nitration and sulphonation);

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Rank: 6
Score: 68.56614
Retrieved Text: The course is aimed at introducing the students into the vast realm of organic chemistry, with a particular emphasis on the structure-activity relationship of the main organic compounds.
The examinations of “General and Inorganic Chemistry” and "Propaedeutic Organic Chemistry' must be passed before that of “Organic Chemistry'.
Functional groups of the main organic compounds. Thermodynamic and kinetic control of organic reactions. Reaction kinetics, activation energy, catalysis. Reaction mechanisms. Radical and ionic reactions. Nucleophilic and electrophilic species. Monomolecular and bimolecular nucleophilic substitutions at saturated carbons. Monomolecular and bimolecular elimination reactions. Organometallic reagents, Grignard reagents. Electrophilic additions to alkenes. Regioselective, stereospecific, and stereoselective organic reactions. Nucleophilic addition to carbon-oxygen double bond. Acyl nucleophilic substitution. Carbon-carbon bond-forming reactions. Reactions of enolizable compounds.
Reactivity, and synthesis of the following compound classes: alkanes, cycloalkanes, alkyl halides, alkenes, alkynes, alcohols, diols, ethers, epoxides, aldehydes, ketones, carboxylic acids, acyl halides, anhydrides, esters, lactones, amides, lactams., imides, nitriles, 1,3-dicarbonyl compounds, alpha,beta-unsaturated compounds, amines.
Structure, reactivity, and synthesis of the following compound classes: benzene, substituted benzenes and, in particular, phenols, aryl halides, and aromatic amines. Structure and reactivity of the main heteroaromatic systems.
1. J. GORZYNSKI SMITH, "Chimica Organica", McGraw-Hill.
2. W.H. BROWN, C.S. FOOTE, B.L. IVERSON, "Chimica Organica", EdiSES, III Edizione.
3. J. McMURRY, "Chimica Organica", Piccin Ed., VI Edizione.
4. S. EGE, "Chimica Organica – Struttura e Reattività", Idelson-Gnocchi Ed., II Edizione Italiana.
5. G. H. SCHMID, "Chimica Organica", Casa Editrice Ambrosiana, Milano.
The final examination consists of one written test, dealing with the resolution of simple problems on organic synthesis, and an oral colloquium.

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Rank: 7
Score: 66.5105
Retrieved Text: It covers all the practical aspects of the subject Pharmaceutical Chemistry II in detail as per the syllabus prescribed by PCI under Education Regulation 1991 for Final Year Diploma in Pharmacy students. It also covers some additional experiments relevant to develop desirable practical skills in them.The text is divided topic-wise into five parts. Part I covers the elemental detection for nitrogen sulphur and halides. Part II covers functional group detection for carboxylic acids alcohols phenols aldehydes ketones esters amides amines nitro group and hydrocarbons. Some experiments for determining the extra elements and functional groups in unknown samples are also added. Part III covers the identification of compounds/drugs/dosage form. Part IV covers synthesis separation and purification of drugs and organic compounds. Part V covers the experiments concerning the determination of the melting point and boiling point. This Manual is expected to clear the theoretical concepts behind each experiment of Pharmaceutical Chemistry II. This would save a valuable time for the students in writing the records which in turn could be ideally utilised by the students in learning and understanding the subject better.

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Rank: 8
Score: 65.50072
Retrieved Text: This Molecular Model Kit has a total of 178 pieces including a link remover. With this set, it is easy to build models for Organic and Inorganic Chemistry!
Build models such as: alkanes, alkenes, alkynes, alky halides, alcohols, ethers, aldehydes, ketones, carboxylic acids, nitriles, amines, esters, aromatic compounds, heterocyclic compounds, and more.
All parts are made of durable and sturdy plastic which are color coded to national standards. This is a great set for both students and teachers to aid in course studies!
Atomic - valence(angle) Color - Qty.
Links - color - length(mm) - Qty.
★ FALL IN LOVE WITH CHEMISTRY --- These are so much fun to play with and they help you understand the relationship between molecules. Let you learn the shapes and chemical makeup of all the functions groups you'v so far learned in O-Chem and Inorganic chemistry.
★ BASIC TO ADVANCED LEARNING --- Perfect for kids and other student, whoever you are senior student or college student. Fantastic learning aid for your. If you have had one at home you can practice with your kids. Meanwhile if you are student to playing with it by yourself to brush up on defunct chemistry skills. The pieces all to be sturdy and well made, and can use it for years to come.
★ MOLECULE SCIENCE IN 3D --- We have prepared 178 Pcs molecular model set for you, This model contains C, H, O, N, P, S, CI, and other metals and a variety of single and double bonds, long bonds, long keys. Can be put high school, university chemistry

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Rank: 9
Score: 65.11767
Retrieved Text: Many of the most useful alpha-substitution reactions of ketones proceeded by way of enolate anion conjugate bases. Since simple ketones are weaker acids than water, their enolate anions are necessarily prepared by reaction with exceptionally strong bases in non-hydroxylic solvents. Esters and nitriles are even weaker alpha-carbon acids than ketones (by over ten thousand times), nevertheless their enolate anions may be prepared and used in a similar fashion. The presence of additional activating carbonyl functions increases the acidity of the alpha-hydrogens substantially, so that less stringent conditions may be used for enolate anion formation. The influence of various carbonyl and related functional groups on the equilibrium acidity of alpha-hydrogen atoms (colored red) is summarized in the following table. For common reference, these acidity values have all been extrapolated to water solution, even though the conjugate bases of those compounds having pKas greater than 18 will not have a significant concentration in water solution.
To illustrate the general nucleophilic reactivity of di-activated enolate anions, two examples of SN2 alkylation reactions are shown below. Malonic acid esters and acetoacetic acid esters are commonly used starting materials, and their usefulness in synthesis will be demonstrated later in this chapter. Note that each of these compounds has two acidic alpha-hydrogen atoms (colored red). In the equations written here only one of these hydrogens is substituted; however, the second is also acidic and a second alkyl substitution may be carried out in a similar fashion.
1. The carbon atom framework or skeleton that is found in the desired compound (the target) must be

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Rank: 10
Score: 62.747486
Retrieved Text: NCERT Textbook Solutions are considered extremely helpful when preparing for your CBSE Class 12 Chemistry board exams. TopperLearning study resources infuse profound knowledge, and our Textbook Solutions compiled by our subject experts are no different. Here you will find all the answers to the NCERT textbook questions of Chapter 12 - Aldehydes, Ketones and Carboxylic Acids.
All our solutions for Chapter 12 - Aldehydes, Ketones and Carboxylic Acids are prepared considering the latest CBSE syllabus, and they are amended from time to time. Our free NCERT Textbook Solutions for CBSE Class 12 Chemistry will strengthen your fundamentals in this chapter and can help you to score more marks in the examination. Refer to our Textbook Solutions any time, while doing your homework or while preparing for the exam.
TopperLearning provides step-by-step solutions for each question in each chapter in the NCERT textbook. Access Chapter 12 - Aldehydes, Ketones and Carboxylic Acids here for free.

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Rank: 11
Score: 60.928684
Retrieved Text: 5-TAMRA cadaverine can used to modify carboxylic acid group in the presence of activators (e.g. EDC, or DCC) or activated esters (e.g. NHS esters) through a stable amide bond. It also can be reversibly coupled to aldehydes and ketones to form a Schiff base – which can be reduced to a generate stable amine derivative by sodium borohydride (NaBH4) or sodium cyanoborohydride (NaCNH3).
Although the mixed isomers of 5(6)-TAMRA cadaverine is a preferred, routinely used orange-fluorescent dye for staining proteins, it is rearly used for labeling peptides and nucleotides. Purification of 5(6)-TAMRA labeled peptide and nucleotides might be troublesome due to significant signal broadening in HPLC purification. Peptides and nucleotides labeled with a single isomer TAMRA usually give better resolution in HPLC purification that is often required in the conjugation processes.
An orange-fluorescent building block used to modify carboxylic acid containing molecules.

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Rank: 12
Score: 60.596928
Retrieved Text: Addition of lithium aluminum hydride to esters leads to the formation of primary alcohols (after addition of acid).
When treated with lithium aluminum hydride abbreviated LAH, esters are reduced to yield primary alcohols. As well as most mechanisms of reduction with LAH (reduction of aldehydes, ketones, carboxylic acids, amines), this process is somewhat complex, so that a simpler version will be shown.
This reaction involves two equivalents of LAH. The first equivalent of LAH reduces the ester to an aldehyde and the second equivalent of LAH reduces the aldehyde to an alcohol. But with only one equivalent is not possible to produce aldehyde because aldehydes are more reactive than esters and will react with LAH immediately after being formed. For this purpose, DiBAl-H is used.
Hydride ion of LAH attacks the carbonyl group and makes methoxide ion a good leaving group that is expelled in the next step. This re-forming a carbonyl group gives the aldehyde as an intermediate. Then this whole procedure is repeated. The second molecule of LAH is used to function as a nucleophile (its hydride ion) and attacks the carbonyl group. After the reaction is complete, the alkoxide ion is protonated with an acid (water in this case).

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Rank: 13
Score: 60.296757
Retrieved Text: We specialize in high efficiency filtration products designed to protect you and the workplace from environmental hazards.
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Rank: 14
Score: 60.156803
Retrieved Text: A bondingness term is further developed to aid in heat of formation (ΔfHº) calculations for C, N, O and S containing molecules. Bondingness originated from qualitative investigations into the antibonding effect in the occupied MOs of ethane. Previous work used a single parameter for bondingness to calculate ΔfHº in an alkane homologous series using an additivity scheme. This work modifies the bondingness algorithm and uses the term to parameterise a test group of 345 molecules consisting of 17 subgroups that include alkanes, alkenes, alkynes, alcohols, ethers, aldehydes, ketones, carboxylic acids, esters, amines, amides, diazenes, nitriles, nitroalkanes, nitrates, thiols and benzenoids. Comparing experimental with calculated ΔfHº values, a standard deviation for the residuals of 6.3 kJ mol 1 can be achieved using bondingness with a simple steric repulsion term (SSR) in a bond additivity scheme, and a standard deviation of 5.2 kJ mol 1 can be achieved using a Lennard-Jones potential. The method is compared with the group method of Pedley, which for a slightly smaller set of 338 molecules, a subset of the test set of 345 molecules, gives a standard deviation of 7.0 kJ mol 1.
Bondingness, along with SSR or a Lennard-Jones potential, is parameterised in the lowest level of ab initio (HF-SCF) or semiempirical quantum chemical calculations. It therefore may be useful in determining the ΔfHº values for the largest molecules that are amenable to quantum chemical calculation.
As part of our analysis we calculated the difference between the lowest energy conformer and the average energy of a mixture populated with higher energy conformers. This

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Rank: 15
Score: 60.00497
Retrieved Text: Quizzes are keyed to chapters in Ouellette (Organic Chemistry - A Brief Introduction, 2/e, 1998). Although the quizzes are indicated for a particular chapter, they often cover material from more than one chapter.
For each quiz, a partial answer key is available online. There is a link to it at the top and bottom of the quiz page. You are also welcome to turn in the quiz, for feedback. Site visitors are welcome to ask me questions about the quiz by email.
My contact information is at the bottom of every page at this site.
Alkanes and cycloalkanes. Includes basic organic nomenclature and isomers. Ouellette Ch 3.
Alkenes, alkynes. Ouellette Ch 4.
Ouellette Ch 3, 4, 8, 10, 12. For a quiz that deals with the general nature of oxidation and reduction, which is part of all these chapters, see the quiz listed below for Ouellette Ch 12. You may work on this quiz at any time along here, from Ouellette Ch 4 to 12.
Aromatic nomenclature: Use of ortho, meta, para. Ouellette Ch 5.
Alcohols, ethers. Ouellette Ch 8-9.
Review quiz, through ethers. This quiz reviews a range of material up though "ethers" (Ouellette Ch 9), including nomenclature, properties, and reactions. Most of this quiz is at "basic" or "core" level. It may be good practice just before Test 2, which typically covers up through Ch 9.
Distinguishing isomers. This quiz deals with many functional groups discussed so far, including C=C double bonds, alcohols, ethers, aldehydes, ketones. It is quite challenging because it brings together so much material -- but that is precisely why

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Rank: 16
Score: 58.187103
Retrieved Text: Odorants are detected by a vast collection of receptors in the nose. Individual sensory neurons probably express a single receptor, and all the neurons that express a particular receptor converge on a few topographically fixed glomeruli in the brain's olfactory bulb (OB). Researchers are keen to see whether there is any functional sorting of olfactory information during this projection process, and now in the October Nature Neuroscience Uchida et al. find that, indeed, odorants with different functional groups are detected by different areas of the brain's olfactory bulb (Nat. Neuro. 2000, 3:1035-1043). Carboxylic acids and aldehydes are detected in an anteromedial domain, whereas alcohols and ketones are detected in a lateral domain. Especially within the anteromedial domain, odorants of increasing carbon chain length are detected by clusters of glomeruli that are nested in more anterior and lateral positions. This is in agreement with data demonstrating that olfactory neurons expressing related receptors project to neighboring glomeruli. The only question now is how this sorting takes place.

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Rank: 17
Score: 57.6841
Retrieved Text: In general, Dr. Zhang's research program utilizes the tools of organic synthesis and physical chemistry, through rational molecular design, to develop novel functional materials (organic or hybrid nanocomposites) with potential applications in carbon capture, molecular separation, controlled nanoparticle synthesis, catalysis, energy storage, light harvesting, and nanomedicine.
Lab. Instruction in experimental techniques of modern organic chemistry emphasizing chemical separations and reactions of alkanes, alkenes, and aromatic compounds. Stereochemical modeling and the identification of organic unknowns by spectroscopic and chemical methods are also introduced. Department enforced corequsite: CHEM 3311 or CHEM 3451. Degree credit not granted for this course and CHEM 3361.
Lect. and rec. Intended primarily for nonmajors. Topics include structure and reactions of alkyl halides, alcohols, ethers, carboxylic acids, aldehydes, ketones, and amines; introduction to the chemistry of heterocycles, carbohydrates, and amino acids; nomenclature of organic compounds; synthesis; and reaction mechanisms. Department enforced corequsite: CHEM 3341 or CHEM 3381. Credit not granted for this course and CHEM 3471 or BCHM 3491.
Lab. Required course for chemistry majors. Instruction in experimental techniques of modern organic chemistry emphasizing chemical separations and reactions of alkanes, alkenes, alcohols, ketones, and alkyl halides. Explores stereochemical modeling and the chemical identification of organic unknowns. Department enforced corequsite: CHEM 3351 or CHEM 3311 or CHEM 3451. Degree credit not granted for this course and CHEM 3321.
Overview of the preparation and functioning mechanism of novel organic materials that have recently been developed, including conductive polymers, 2-D macrocyclic structures, 3-D molecular cages, molecular machines/muscles/switches, fullerene derivatives and carbon nanotube composites. Emphasizes the use of organic and physical chemistry

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Rank: 18
Score: 57.315216
Retrieved Text: Physical Data: mp 500 °C (dec); d 11.14 g cm-3.
Solubility: sol dilute HCl, HNO3; insol water, ethanol.
Form Supplied in: commercially available in both yellow and red crystalline forms.
Handling, Storage, and Precautions: highly toxic; oxidizer; protect from light.
Conversion of Ketones into Unsaturated Aldehydes.
Mercury(II) oxide promotes the Wittig-thio-Claisen rearrangement sequence which converts ketones into unsaturated aldehydes (eq 1).2 The reaction proceeds via formation of an allyl vinyl sulfide followed by rearrangement to form the a-allyl aldehyde.
Preparation of Aldehydes and Ketones by Hydrolysis of Sulfur-Containing Compounds.
A mixture of mercury(II) oxide/35% aqueous Tetrafluoroboric Acid/THF can be used for the hydrolysis of 1,3-benzodithioles (eq 2), 1,3-benzoxathioles (eq 3), 1,3-oxathiolanes (eq 4), 1,3-dithiolanes (eq 5), and 1,3-dithianes (eq 6).3 These reaction conditions offer an alternative to those reported by Vedejs and Fuchs19 which use a mixture of mercury(II) oxide/Boron Trifluoride Etherate/THF.
Synthesis of Esters by Solvolysis of a-Hydroxy Thioorthoesters.
Cyclization of Primary and Secondary Alcohols to Yield Tetrahydrofurans.
Synthesis of b-Substituted Polynitroalkyl Vinyl Ethers.
The inherent instability of b-substituted polynitroaliphatic alcohols in acidic and basic media precludes the use of traditional vinyl ether synthesis. The use of mercury(II) oxide/Trifluoroacetic Acid in refluxing dichloromethane permits a one-step, high-yielding synthesis of b-substituted polynitroalkyl ethers (eq 10).6 The use of mercury(II) oxide alone produces the product in 20-30% yield, whereas the addition of TFA as cocatalyst substantially increases the yield of the desired product.
The mercuration of alkenes using mercury(II) oxide and tetrafluoroboric acid in the presence of excess amine leads to the formation of 1,2-diamines (eq 12).8 Presumably, the reaction takes place via formation of a b-aminomercury(II) tetrafluoroborate which

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Rank: 19
Score: 57.30924
Retrieved Text: Thiocarbonyl derivatives of secondary alcohols are readily reduced by diphenylsilane in a radical chain process at room temperature using triethylborane-air as an initiator. An improved radical chain procedure for the deoxygenation of secondary and primary alcohols using diphenylsilane as hydrogen atom donor and triethylborane-air as initiator. Diphenylsilane is a reagent in the invention of radical reactions for deoxygenation of alcohols via their thiocarbonyl derivatives, deamination via isonitriles, and dehalogenation of bromo- and iodo- compounds by radical chain chemistry. Fluorescent film sensor for vapor-phase nitroaromatic explosives via monolayer assembly of oligo(diphenylsilane) on glass plate surfaces. Reductions of carboxylic acid derivatives by silanes in the presence of rhodium complexes were studied. Carboxylic esters were reduced to alcohols by diphenylsilane catalyzed by [RhCl (cod)] 2/4PPh 3 or [RhCl (PPh 3) 3] at room temperature in up to 99% yields. Sequential C- Si bond formations from diphenylsilane and its application to silanediol peptide isostere precursors.
Store in cool place. Keep container tightly closed in a dry and well-ventilated place. Store away from strong oxidizing agents, bases, haevy metal powders.
John L. Speier,; Ruth Zimmerman,; James Webster. The Addition of Silicon Hydrides to Olefinic Double Bonds. Part I. The Use of Phenylsilane, Diphenylsilane, Phenylmethylsilane, Amylsilane and Tribromosilane. J. Am. Chem. Soc., 1956, 78 (10), 2278-2281.
Lone Nielsen and Troels Skrydstrup. Lone Nielsen and Troels Skrydstrup. J. Am. Chem. Soc., 2008, 130 (39), 13145-13151.
Protection of diols as diphenylsilylenes can be effected in the presence of CsF: J. Organomet. Chem., 282, 155 (1985). See Diphenyl­dichlorosilane, A12051, and Appendix 4.
Reducing agent used in combination with F- or

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Rank: 20
Score: 55.370174
Retrieved Text: This is a comprehensive course for those fields requiring knowledge of general chemical concepts. Emphasis is on applied areas of interest where aspects of atomic and molecular structure and function are particularly important. Topics covered include stoichiometry of chemical reactions, energy interrelationships between reactants, atomic structure and chemical bonding.
Prerequisite(s): MATH1020 or math placement, Corequisite: CHM1005.
This is a laboratory companion course coordinated with CHM1000. Emphasis is on inquiry-based exercises that illustrate and demonstrate important skills and principles of theoretical chemistry and applied chemistry. Topics covered include stoichiometry of chemical reactions, energy interrelationships between reactants, atomic and molecular structure, and chemical bonding.
Prerequisite(s): MATH1020 or math placement, Corequisite: CHM1000.
This is the first course in general chemistry. Students take an active-learning approach to the discovery of scientific measurements, atomic structure, stoichiometry, thermochemistry, electron configurations, bonding models for chemical compounds, VSEPR (Valence Shell Electron Pair Repulsion) and gases.
Prerequisite(s): MATH1020 or math placement, Corequisite: CHM1015.
This is a laboratory companion course coordinated with CHM1011 that introduces students to techniques and equipment used in experimental chemistry. Students take an inquiry-based, self-guided learning approach to the discovery of the structure of the atoms, scientific measurements, proper calculations of chemical reactions, thermochemistry, spectroscopy, and the states of matter. Students also identify, when appropriate, the application of Green Chemistry procedures. Additionally, this laboratory course provides students with the opportunity to practice laboratory safety, design experimental procedures, collect data, analyze results and discuss conclusions.
Prerequisite(s): MATH1020 or math placement, Co-requisite: CHM1011.
This course examines the chemistry of carbon-containing molecules relevant to biological systems such as the human body, beginning with

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Rank: 21
Score: 54.33649
Retrieved Text: What Is Oxidation of a Tertiary Alcohol?
Tertiary alcohols do not undergo oxidation in the presence of an oxidizing agent. This is because the carbon atom that contains the alcohol functional group is devoid of any hydrogen atoms, which are necessary in the oxidation mechanism of alcohols.
There are three types of alcohols, which are classified based on the number of hydrogen atoms bonded to the carbon atom that is bonded to the oxygen atom in the functional group of an alcohol. Primary alcohols have two hydrogen atoms, secondary alcohols have one hydrogen atom and tertiary alcohols have no hydrogen atoms bonded to the carbon that is bonded to the oxygen atom.
Oxidation of alcohols can only take place in the presence of an oxidizing agent, such as acidified potassium dichromate, which in turn is reduced during the process. The dichromate (IV) ions are reduced to chromium (III) ions through the addition of electrons. This process involves the removal of the hydrogen atoms bonded to the oxygen itself in the alcohol?s functional group, as well as from the carbon containing the alcohol group (known as the carbinol carbon).
Since primary alcohols contain two hydrogen atoms on the carbinol carbon, they can be oxidized to aldehydes and then to carboxylic acids. Secondary alcohols can be oxidized only once to ketones, since they contain only one hydrogen atom on the carbinol carbon. Tertiary alcohols are resistant to oxidation, since their carbinol carbons have no hydrogen atoms that can take part in the transfer of electrons to the dichromate ions.
What Is the Hottest

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Rank: 22
Score: 53.68998
Retrieved Text: STABILITY The stability depends upon dissolved oxygen and MEHQ inhibitor. The presence of oxygen is necessary for inhibitor to prevent polymerization.
Acrylic acid is the simplest unsaturated carboxylic acid which has double bond and carboxyl group in C3 one molecule with the formula CH2=CHCOOH. The vinyl group is attached to the carbonyl carbon directly. The systemic name is 2-propenoic acid. Acrylic acid has two reaction points or functional groups required for polymerization process. Purified (glacial) acrylic acid is a clear, colorless liquid with a characteristic acrid odor. It is miscible with water, alcohols and ethers. Acrylic acid is produced from C 3 refinery. Acrylic acid undergoes the typical reactions of a carboxylic acid and forms acrylic esters - basic alkyl esters are methyl, butyl, ethyl acrylate, and 2-ethylhexyl acrylate. Acrylic acid and its esters undergo the reactions of the double bond which readily combine with themselves or other monomers (e.g amides, methacrylates, acrylonitrile, vinyl, styrene and butadiene) to form homopolymers or co-polymers which are used in the production of coatings, adhesives, elastomers, super absorbent polymers, flocculants, as well as fibres and plastics. Acrylate polymers show a wide range of properties dependent on the type of the monomers and reaction conditions.
Alkyl acrylates are clear, volatile liquid; slightly soluble in water and complete soluble in alcohols, ethers and almost organic solvents; Acrylate esters containing a double bond and functional carboxyl group are used chiefly as a monomer or co-monomer in making acrylic and modacrylic fibres. It is used in formulating paints and dispersions for paints, inks, and adhesives. It

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Rank: 23
Score: 53.43784
Retrieved Text: Identify the aldehyde, ketone, acid, ester, and ether functional groups.
The other two bonds on the C atom are attached to other atoms. It is the identities of these other atoms that define what specific type of compound an organic molecule is.
There is another way to name ketones: name the alkyl groups that are attached to the carbonyl group and add the word ketone to the name. So propanone can also be called dimethyl ketone, while 2-butanone is called methyl ethyl ketone.
Draw the structure of 2-pentanone.
The combination of a carbonyl functional group and an OH group makes the carboxyl group.
How acidic are carboxylic acids? It turns out that they are not very acidic. No carboxylic acid is on the list of strong acids (Table 12.4.1). This means that all carboxylic acids are weak acids. A 1 M solution of formic acid is only about 1.3% dissociated into H+ ions and formate ions, while a similar solution of acetic acid is ionized by about only 0.4%. Some carboxylic acids are stronger—for example, trichloroacetic acid is about 45% dissociated in aqueous solution. But no carboxylic acid approaches the 100% dissociation amount required by the definition of a strong acid.
Carboxylate ions are named from the acid name: the -oic acid is replaced with -oate to name the ion.
The anion is the methanoate ion, which is commonly called the formate ion.
Give an alternate but acceptable name to the molecule in Exercise 3b.
Give an alternate but acceptable name to the molecule in Exercise 4b.
The drug known as aspirin has this molecular structure:

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Rank: 24
Score: 53.289196
Retrieved Text: Amines are molecules that contain a basic nitrogen atom. They are derived from ammonia, where one or its hydrogen atoms has been replaced with a carbon group, most commonly an aryl (ring-structured hydrocarbons) or alkyl group.
Amines are used widely in bioactive molecules, drugs, and various organic materials, and preparing them is one of the most important tasks for synthetic chemists in both academia and industry. While many methods are now available for synthesizing amines containing aryl groups, the synthesis of amines containing alkyl groups still pose a challenge.
Now, the lab of Xile Hu at EPFL has developed a new method that can efficiently produce alkyl amines by using photocatalysis alongside copper catalysis. The photocatalysis allowed the chemists to start with alkyl redox-active esters instead of the usual alkyl halides, which are limited in terms of availability, stability, and are sometimes toxic.
The esters can be easily prepared from alkyl carboxylic acids, which are readily available, stable, and non-toxic. The copper catalysis was then used to link the alkyl unit generated in photocatalysis with a nitrogen-containing coupling partner to generate alkyl amines.
"Although metal-catalyzed cross coupling reaction has completely revolutionized the synthesis of aryl amines, it can hardly be used to synthesize alkyl amines," says Xile Hu. "The reason is that the necessary metal alkyl intermediates tend to decompose, and the alkyl-nitrogen ligation becomes difficult."
The work provides a new and efficient approach for the synthesis of alkyl amines, which has potential applications in the pharmaceutical and fine chemical industries. It offers high selectivity, compatibility with a large number of

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Rank: 25
Score: 53.064754
Retrieved Text: Rationalize living systems based on general principles of chemistry. Presenting the organic chemistry as a subset of Chemistry.
1 - Introduction to Organic Chemistry.
2 - Structural Chemistry. Study of the three-dimensional structure of the major classes of compounds of carbon. Models of chemical bonding.
3 - Stereoisomerism and molecular conformation.
4 - Structure and Reactivity of carbon compounds. Effects inductive and resonance or mesomeric. Relocation of the chemical bond (resonance structures and the resonance hybrid). Nucleophiles and electrophiles. Reactive Intermediates: free radicals, carbocations and carbanions.
5 - Saturated hydrocarbons: alkanes and cyclo-alkanes. Physical and chemical properties; Some reactions characteristics. Mechanism halogenation reactions (free radicals). CFC (s) and its importance in the chemistry of the atmosphere.
6 - Unsaturated Hydrocarbons: Alkenes. Physical and chemical properties; Addition reactions.
7 - aromatic compounds. Resonance energy. Reactions characteristics. Its importance in the environment.
8 - Compounds containing functional groups (containing alcohols, phenols, amines, aldehydes, ketones, carboxylic acids and derivatives); Physical and chemical properties;Representative examples and their biological importance and in the environment.
Will be performed 4 laboratory works .
P1- Introduction to glassware: your specifications and handling.
P2- Extraction and solubility of benzoic acid.
Lectures taught using PowerPoint presentations. Theoretical and practical problem solving and discussion of theoretical aspects concerning the practical classes. Practical classes to perform laboratory work in groups of two or three students, following a written protocol.
Admission to the examination is made by the attendance of at least 3/4 of the classes, theoretical and practical.
- Respond to questions from the teacher in practical classes and theoretical-practical classes .
At the end of the curricular unit, these works will be

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Rank: 26
Score: 52.8334
Retrieved Text: Pro-fragrance copolymeric compounds are described, which provide improved substantivity to surfaces, especially fabrics and which can be easily incorporated in a variety of formulations, particularly in aqueous formulations like detergents and cleaning agents as well as cosmetic preparations without being subject to excessive hydrolysis in the formulation. The pro-fragrance copolymeric compounds enable a long-lasting release of fragrance aldehydes and/or ketones.
The invention relates to pro-fragrance copolymeric compounds obtainable by the copolymerization of specific monomers, their use and detergents and cleaning agents containing same, fabric softeners and cosmetics as well as a method for prolonging the scent perception of such agents.
An alternative to direct addition of scent substances to detergents and cleaning agents, fabric softeners and cosmetics is the use of so-called pro-fragrances. By analogy with prodrugs, pro- fragrances are chemical derivatives of a scent, which reduce the volatility of the scent, for example, and allow delayed release of the scent over time under ambient conditions. By derivatization of scents, such as scent aldehydes or scent ketones, the vapor pressure of these compounds can be lowered. Since the derivatization reaction is reversible, the chemically bound perfume aldehyde or perfume ketone may under certain conditions, e.g., ambient conditions, be cleaved at the bonding site. This releases the perfume or scent substance, which was stored before in the pro-fragrance molecule or compound. This makes a prolonged scent impression possible.
The object of the present invention is to provide pro-fragrances which allow a prolonged scent impression with scent aldehydes and/or scent ketones.
R9 represents a hydrophilic moiety, which contains a polar functional group

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Rank: 27
Score: 52.74322
Retrieved Text: Ketene, any of a class of organic compounds containing the functional grouping C=C=O; the most important member of the class being ketene itself, CH2=C=O, which is used in the manufacture of acetic anhydride and other industrial organic chemicals. The name suggests that ketenes are unsaturated ketones, but their chemistry resembles that of carboxylic acid anhydrides.
Ketene is prepared by heating acetic acid or acetone to about 700 °C (1,300 °F).
Ketene is remarkably reactive; it combines with compounds containing an easily replaced hydrogen atom to yield derivatives of acetic acid. The only important industrial use of ketene itself is its reaction with acetic acid to form acetic anhydride.
Ketene reacts with aldehydes and ketones to form enol acetates or β-lactones.
In the absence of a reactive substrate, ketene combines with itself to form diketene, a β-lactone used industrially to prepare derivatives of acetoacetic acid, such as ethyl acetoacetate and acetoacetamides.
The higher ketenes are generally synthesized by elimination of hydrogen chloride from acyl chlorides. The substituted ketenes react like ketene, but less vigorously. The lactone dimers of long-chain monoalkylketenes have been used as sizing agents for paper.
Ketene, a colourless, irritant gas, is toxic, producing delayed respiratory damage. The high reactivity of all ketenes makes them somewhat dangerous.

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Rank: 28
Score: 52.713802
Retrieved Text: How will you prepare benzyl alcohol from benzaldehyde with out using a reducing agent ?
Explain Half Life of a reaction.
r atomic mass of gold 197u , atomic radius=0.144nm crystallizes in a face centred cubix unit cell . Determine the density of gold?
Why Carboxylic acids have higher boiling point than aldehyde ketone and alcohols?
Explain any two methods of Preparation of aldehydes.
Give the uses of Ethers.
Phenol is more acidic than Alcohols. Why?
Why Alcohols and Phenols are soluble in water.
How are Alcohols and Phenols are formed.
What are Proteins . Give the structures of Proteins.
List the Several materials obtained from cellulose.
What are Natural Rubber and Synthtic Rubber.

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Rank: 29
Score: 52.69319
Retrieved Text: 1). State and explain faraday’s laws of Electolysis.
2). What are electrochemical cells? Describe briefly fuel cell.
3). How is Nitric acid prepared from Ostwald’s process? Give its reaction with Zinc and Iron.
4). What are interhalogen compounds? Why are these named so? Give structure of CIF3 and CIF5.
5). Describe briefly the oxidation state of 3d-transition series elements along with the paramagnetic behaviour of the ions/metals of this series.
6). KMnO4 acts as a strong oxidizing agent in acidic, basic and neutral medium. Give two examples in each case.
7). How can aromatic aldehydes and ketones be prepared by the following reactions?
8) What are carboxylic acids? Describe the general methods of preparation of carboxylic acids.
Explain with suitable examples the Dielctric properties of solids.
What is Arrhenius equation? Discuss its importance.
40 gm of NaOH are prepared in one deciliter of solution. Calculate mole fraction of NaOH.
What are phenols? How do they differ structurally from aromatic alcohols?
Describe the main postulates of Vernier’s theory of Co-ordination compounds.
Name the oxy-acids of Phosphorous. Write their structures.
What are Antihistamines? Give examples.
Why is the time saved when cooking is clone in a pressure cooker?
Distinguish between Physical and Chemical absorption.
Will elevation in boiling point be same for 0.1 M NaCI and 0.1 M Sucrose Solution?
Briefly explain the term Electrophoresis.
What are Haloalkanes? How can haloalkanes be prepared from Alcohols?
KMnO4 acts as a strong oxidising agent in acidic, basic and neutral medium. Give two example in each case.
Describe briefly the oxidation, State of 3d-transition series elements along with the paramagnetic behaviour of the ions/metals of this series.
How can aromatic aldehydes and ketones

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Input Text: Answer the following question given this paragraph: 

39.2 Gas Exchange across Respiratory Surfaces The lungs can hold a large volume of air, but they are not usually filled to maximal capacity. Lung volume measurements include tidal volume, expiratory reserve volume, inspiratory reserve volume, and residual volume. The sum of these equals the total lung capacity. Gas movement into or out of the lungs is dependent on the pressure of the gas. Air is a mixture of gases; therefore, the partial pressure of each gas can be calculated to determine how the gas will flow in the lung. The difference between the partial pressure of the gas in the air drives oxygen into the tissues and carbon dioxide out of the body.


Q: Tidal volume, expiratory reserve volume, inspiratory reserve volume, and residual volume are all types of what kind of measurement?

 Choices:

- respiratory volume

- breathing volume

- emitted volume

- lung volume

A:

Target Text: lung volume

#### Retrieved Documents ####

Rank: 0
Score: 104.399284
Retrieved Text: Distinguish, differentiate, compare and explain what is the main difference between Inspiratory and Expiratory Capacity. Comparison and Differences.
1. Inspiratory capacity is the total volume of air that can be inhaled after a normal expiration. Expiratory capacity is the total volume of air a person can expire after a normal inspiration.
2. Inspiratory capacity includes tidal volume and the inspiratory reserve volume (IC = TV + IRV). Expiratory capacity includes tidal volume and expiratory reserve volume (EC = TV + ERV).
3. Inspiratory capacity is about 3000 to 3500 mL of air. Expiratory capacity is about 1500 to 1600 mL of air.

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Rank: 1
Score: 95.20262
Retrieved Text: Portable Dry Spirometer is rated 4.0 out of 5 by 2.
Measurements of lung functions can vary dramatically from person to person. You can easily demonstrate and measure these differences in your classroom with this accurate, easy-to-use, handheld, dry gas meter. It measures vital capacity, tidal volume, and expiratory reserve volume. Students can then calculate inspiratory reserve volume and inspiratory capacity from these values.
Measurements of lung functions can vary dramatically from person to person. You can easily demonstrate and measure these differences in your classroom with this accurate, easy-to-use, handheld, dry gas meter. It measures vital capacity, tidal volume, and expiratory reserve volume. Students can then calculate inspiratory reserve volume and inspiratory capacity from these values. No calibration needed. The gauge is calibrated to 7 L in 100-cc increments. Just reset the needle after each reading by rotating the dial. Includes 50 reusable mouthpieces, 7/16" ID. Pack of 100 disposable mouthpieces (item #692671) sold separately.
Rated 3 out of 5 by Biogeek from Barely a yes These spirometers are easy to use, however they stop working after regular lab use and are not repairable.
Rated 5 out of 5 by Suursnautseri from Cardboard Mouthpiece Its a cardboard tube, can't get more basic than that. Easily attached to spirometers and gets the job done. Recyclable!

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Rank: 2
Score: 92.60586
Retrieved Text: Inspiratory Reserve Volume (IRV) + Expiratory Reserve Volume (ERV) + Tidal Volume (TV) Normal adult: 3 to 5 Liters; . Vital Capacity decreases 200 to 250 cc per 10 .
Hi does anyone know how much volume is given per squeeze from an adult ambu bag? Just curious and I could not seem to find this info on the manufacturer's site.
Values for normal respiratory rate at depend on age and activity: . The normal respiratory rate in all adults is about 12 breaths/min. . Normal tidal volume .

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Rank: 3
Score: 91.36249
Retrieved Text: Estimates the pulmonary VC based on tidal, inspiratory and expiratory reserve volumes.
In the text below the form there is more information about the calculation method used.
Vital capacity is defined as the maximum amount of air possible to be expelled after a maximum inhalation.
It is being calculated based on three respiratory volumes: tidal, inspiratory and expiratory reserve volumes.
Vital capacity is an indicator of respiratory function that is based on three pulmonary volumes, which are measured via lung function tests (spirometry).
Inspiratory reserve volume (IRV) 3.1 1.9 The additional air possible to be inhaled forcefully after the normal tidal volume inspired.
Tidal volume (TV) 0.5 0.5 The amount of air which can be inhaled and exhaled during relaxed breathing at a rate of 12 to 20 breaths per minute.
Expiratory reserve volume (ERV) 1.2 0.7 The additional air that can be extracted during forced exhalation, after the expiration of the normal tidal volume.
In the light of the above, vital capacity can be defined as the maximum amount of air possible to be expelled after a maximum inhalation.
Normal values in adults are between 3 and 5 litres and depend on gender, age, weight, height and ethnicity.
Taller individuals tend to have higher vital capacities (differences of 0.8L for every 6 in of height).
Also, there is a functional difference between VC levels during 20s and 30s and those at 50s.
Lower than normal values are suggestive of a restrictive lung disease (e.g. pulmonary fibrosis, pneumothorax).
Normal values don’t necessarily guarantee the absence of respiratory condition, for example in obstructive lung diseases (e.g. asthma, emphysema or chronic

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Rank: 4
Score: 85.65951
Retrieved Text: Lung hyperinflation commonly accompanies expiratory flow limitation in patients with chronic obstructive pulmonary disease (COPD) and contributes importantly to morbidity and an impoverished quality of life. It is not surprising, therefore, that lung hyperinflation has become an important therapeutic target in symptomatic COPD patients. Acute dynamic increases in lung hyperinflation under conditions of worsening expiratory flow limitation and increased ventilatory demand (or both) can seriously stress cardiopulmonary reserves in patients with more advanced disease. The present understanding of the physiological mechanisms of dynamic hyperinflation during exacerbations of COPD and during physical activity continues to grow, together with an appreciation of its negative mechanical and sensory consequences. In this brief overview, definitions and measurement of lung hyperinflation during rest and exercise will be discussed and its potential clinical importance will be considered. The focus will mainly be on current concepts of the mechanisms of air trapping and its role in inducing respiratory discomfort and activity limitation in COPD.
Expiratory flow limitation (EFL) is the pathophysiological hallmark of chronic obstructive pulmonary disease (COPD) and arises because of the dual effects of permanent parenchymal destruction (emphysema) and airway dysfunction, which in turn reflect the effects of small airway inflammation (mucosal oedema, airway remodelling and mucous impaction) and possibly increased cholinergic airway smooth muscle tone (fig. 1⇓). Emphysema results in reduced lung elastic recoil pressure, which leads to a reduced driving pressure for expiratory flow through narrowed and poorly supported airways in which airflow resistance is significantly increased. EFL is said to be present “when the expiratory flows generated during spontaneous tidal

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Rank: 5
Score: 84.21984
Retrieved Text: (vol'yŭm), Avoid the misspelling volumn.
Space occupied by matter, expressed usually in cubic millimeters, cubic centimeters, liters, etc. See: water.
/vol·ume/ (vol´ūm) the measure of the quantity or capacity of a substance. Symbol V or V.
end-diastolic volume (EDV) the volume of blood in each ventricle at the end of diastole, usually about 120–130 mL but sometimes reaching 200–250 mL in the normal heart.
end-systolic volume (ESV) the volume of blood remaining in each ventricle at the end of systole, usually about 50–60 mL but sometimes as little as10–30 mL in the normal heart.
expiratory reserve volume the maximal amount of gas that can be exhaled from the resting end-expiratory level. Abbreviated ERV.
forced expiratory volume the fraction of the forced vital capacity that is exhaled in a specific number of seconds. Abbreviated FEV with a subscript indicating how many seconds the measurement lasted.
mean corpuscular volume the average volume of erythrocytes, conventionally expressed in cubic micrometers or femtoliters per red cell.
minute volume (MV) the quantity of gas exhaled from the lungs per minute; tidal volume multiplied by respiratory rate.
packed-cell volume (PCV), volume of packed red cells (VPRC) hematocrit.
residual volume the amount of gas remaining in the lung at the end of a maximal exhalation.
stroke volume the volume of blood ejected from a ventricle at each beat of the heart, equal to the difference between the end-diastolic volume and the end-systolic volume.
tidal volume the volume of gas inhaled and exhaled during one respiratory cycle.
the amount of space occupied by a body, expressed in units of cubic distance.
Vox populi A measure of the capacity

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Rank: 6
Score: 76.166626
Retrieved Text: Since lung function is the most important factor regarding survival in ALS, and since I have not been given a pulmonary test for a year, I purchased a spirometer and started logging my main lung parameters daily, starting on Jan 3, 2014. The logging is done through a php script directly to a database, and the results are visible in real time in the chart below.
The starting values are around 60 % of nominal, so I did not start a minute too early.
FVC - forced expiratory vital capacity: The volume change of the lung between a full inspiration to total lung capacity and a maximal expiration to residual volume.
FEV1 - forced expiratory volume in 1 second: The FEV1 is the volume exhaled during the first second of a forced expiratory maneuver started from the level of total lung capacity.
PEF - peak expiratory flow: Peak expiratory flow (PEF) is the maximum flow generated during expiration performed with maximal force and started after a full inspiration.
FEF2575 - maximum midespiratory flow: The MMEF (maximum midexpiratory flow) is the average expiratory flow over the middle half of the FVC.
FIVC - forced inspiratory vital capacity: The volume change of the lung between a maximal expiration to residual volume and a full inspiration to total lung capacity.

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Rank: 7
Score: 72.85782
Retrieved Text: the graph produced by plotting the instantaneous flow of respiratory gas against the simultaneous lung volume, usually during maximal forced expiration.
a graphic of the instantaneous rate of airflow during a forced expiration. It is plotted as a function of the volume. It may be a maximum expiratory flow-volume curve or a partial expiratory flow-volume curve.
Graphic produced by plotting the instantaneous flow of respiratory gas against the simultaneous lung volume, usually during maximal forced expiration.
Inspiratory flow-volume curve evaluation for detecting upper airway disease.
The PEF is obtained from flow-volume curve data, and should be reported.
1) are graphic displays produced by spirometers, and include volume-time curves (from both types of spirometers) and flow-volume curves (from newer flow-type spirometers).
It has been shown that maximum expiratory flow-volume curve (MEFVC) values measured by plethysmograph remain higher than values measured at the mouth.
Effect of thoracic gas compression on the flow-volume curve of the forced vital capacity.
Calculated as a percentage and graphed as a time-volume curve or a flow-volume curve.
Expiratory flow-volume curves were recorded by a spirometer with a pneumotachograph sensor (Model ST90, Fukuda Sangyo Co.
Abnormal inspiratory flow-volume curves in patients with sleep-disordered breathing.
However, Mallory did not have a direct, automated way to monitor flow-volume curves remotely.
1] <85% and good flow-volume curves also were considered technically acceptable.
6) The authors provided no description of criteria for inadequate flow-volume curves, except to state that "the QA officer used the review software to inspect all flow-volume tracings from subjects with questionable performance, overriding the selection of the spirometer software algorithm of the `best' maneuver on rare occasions.

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Rank: 8
Score: 72.79081
Retrieved Text: Flow Waveforms and Inspiratory: Expiratory Relationship. In: Hess DR, Kacmarek RM. Hess D.R., Kacmarek R.M. Eds. Dean R. Hess, and Robert M. Kacmarek.eds. Essentials of Mechanical Ventilation, 4e New York, NY: McGraw-Hill; . http://accessanesthesiology.mhmedical.com/content.aspx?bookid=2493&sectionid=199646410. Accessed April 24, 2019.
. "Flow Waveforms and Inspiratory: Expiratory Relationship." Essentials of Mechanical Ventilation, 4e Hess DR, Kacmarek RM. Hess D.R., Kacmarek R.M. Eds. Dean R. Hess, and Robert M. Kacmarek. New York, NY: McGraw-Hill, , http://accessanesthesiology.mhmedical.com/content.aspx?bookid=2493&sectionid=199646410.
Apply the concept of time constant to the physiology of mechanical ventilation.
Compare constant flow and descending ramp flow patterns during volume-controlled ventilation (VCV).
Describe the effect of respiratory mechanics on the airway pressure waveform during VCV.
Describe the effect of resistance and compliance on flow during pressure-controlled ventilation (PCV).
Describe the effect of rise time adjustment during PCV and pressure support ventilation (PSV).
Describe the effect of termination flow during PSV.
Discuss the role of sigh breaths during mechanical ventilation.
Discuss the physiologic effects of I:E manipulations.
Microprocessor-controlled ventilators allow the clinician to choose among various inspiratory flow waveforms. This chapter describes the technical and physiologic aspects of various inspiratory waveforms during mechanical ventilation.
where Vt is the volume of a lung unit at time t, Vi is the initial volume of the lung unit, e is the base of the natural logarithm, and τ is the time constant. The relationship between Vt and τ is illustrated in Figure 9-1. Note that the volume change is nearly complete in five time constants.
The time constant function for lung emptying. After one time constant, 37% of the volume remains in the lungs, 13% remains after two

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Rank: 9
Score: 72.40453
Retrieved Text: Airway pressures, tidal volumes, and mortality in patients with acute respiratory distress syndrome.
OBJECTIVE: To determine the usual practice for setting tidal volume and other ventilatory parameters in patients with acute respiratory distress syndrome (ARDS) in the late 1990s and to determine the independent effects of these practices on intensive care unit mortality. DESIGN: Subanalysis of a prospective observational study. Multivariable logistic regression was used to analyze the effects of ventilatory management on mortality. SETTING: A total of 361 intensive care units in 20 countries in March 1998. PATIENTS: A total of 467 mechanically ventilated patients with ARDS. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The mean tidal volume used in the first week of ARDS was 8.8 mL/kg measured body weight, and there was great variability in these tidal volumes (sd = 2.0). Tidal volumes were significantly lower in patients with (n = 265) than without (n = 202) a recorded plateau pressure (8.6 vs. 9.1 mL/kg, p = .01). The overall intensive care unit mortality rate was 60.2%. In addition to the strong influence of organ failures and higher levels of inspired oxygen, late-onset ARDS (onset after >48 hrs of mechanical ventilation; odds ratio, 2.09) was independently associated with mortality. In addition, lower levels of positive end-expiratory pressure were independently associated with higher mortality (odds ratio, 0.91; 1 cm of H2O increments). Neither inspiratory pressures nor tidal volumes were independently associated with mortality, and there was no evidence of increased mortality with the use of lower inspiratory pressures. CONCLUSIONS: This descriptive study demonstrated considerable interpatient variability

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Rank: 10
Score: 70.11497
Retrieved Text: Mechanical ventilation is also called positive pressure ventilation. Following an inspiratory trigger, a predetermined mixture of oxygen is forced into the central airways and then flows into the alveoli. As the intra alveolar pressure increases, termination signal eventually causes the ventilator to stop pumping air into the central airways and the central airway pressure decreases. Expiration follows passively, with air flowing from the higher pressure alveoli to the lower pressure central airways.
Mechanical ventilators are set to deliver a constant volume (volume cycled), a constant pressure (pressure cycled), or a combination of both with each breath. Modes of ventilation that maintain a minimum respiratory rate regardless of whether or not the patient initiates a spontaneous breath are referred to as assist-control (A/C). Because pressures and volumes are directly linked by the pressure-volume curve, any given volume will correspond to a specific pressure, and vice versa, regardless of whether the ventilator is pressure or volume cycled.
Adjustable ventilator settings differ with mode but include respiratory rate, tidal volume, trigger sensitivity, flow rate, waveform, and inspiratory/expiratory (I/E) ratio.
International Journal of Physical Medicine & Rehabilitation, Journal of Physiotherapy & Physical Rehabilitation, International Journal of Ventilation, Journal of Aerosol Medicine and Pulmonary Drug Delivery, Clinical Medicine: Circulatory, Respiratory and Pulmonary Medicine, Journal of Cardiopulmonary Rehabilitation, Pulmonary Pharmacology and Therapeutics.

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Rank: 11
Score: 69.30021
Retrieved Text: Yandong Jiang, M.D., Ph.D.; Robert M. Kacmarek, Ph.D., R.R.T.
*Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts.
We thank Dr. Haghshenas for his interest in our recent paper.1 We appreciate his comments and suggestions and will address his concerns in this letter.
First, it is important to define the primary purpose of this study; to determine if nasal ventilation was more effective than oral-nasal ventilation in the patient with difficult mask ventilation. We created difficult mask ventilation by maintaining the patients’ head in the neutral position since patients under anesthesia in head neutral position more likely have airway obstruction than in head extension position.2 Our goal was not to identify the level of airway obstruction. We assumed that the level of obstruction would be constant if the head was kept in the neutral position regardless of the approach to mask ventilation. Thus our primary end point was the effectiveness of ventilation. We chose to determine effectiveness by the amount (volume) of carbon dioxide removed per breath using either ventilation approach. Other variables also contribute to the assessment of effective ventilation and indeed we also assessed tidal volume, peak inspiratory pressure and volume of carbon dioxide removed per breath/cm H2O pressure applied during the two approaches.
Dr. Haghshenas suggests that we should have used the pressure control mode instead of volume control mode. We believe that either approach to ventilatory assistance could have been used to assess the effectiveness of ventilation. However, each has its limitations. In pressure mode ventilation, pressure is limited and in volume mode ventilation, volume is

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Rank: 12
Score: 68.44049
Retrieved Text: Antoine Vieillard-Baron, M.D.; Roch Augarde, M.D.; Sebastien Prin, M.D.; Bernard Page, M.D.; Alain Beauchet, M.D.; et al François Jardin, M.D.
* Associate Professor, † Resident Head, ‡ Assistant Senior, ∥ Professor, Medical Intensive Care Unit, § Medical Engineer, Department of Biostatistics.
Received from the Medical Intensive Care Unit and the Department of Biostatistics, University Hospital Ambroise Paré, Assistance Publique Hôpitaux de Paris, Boulogne, France.
ADVERSE hemodynamic consequences of mechanical ventilation are essentially mediated by changes in left ventricular preload produced by positive airway pressure. 1 Because pulmonary circulation, including pulmonary arteries, capillaries, veins, and the left atrium, represents the filling reserve for the left ventricle and because this reserve is supplied with blood by the right ventricle, diastolic and systolic right ventricular (RV) changes produced by positive airway pressure are important to consider in an individual patient with an inadequate circulatory adaptation to mechanical ventilation. In particular, positive airway pressure impairs venous return, 2 thus limiting RV diastolic filling, and increases RV outflow impedance, 3 thus impairing RV systolic function. The final result is a reduced RV stroke output, resulting in an incomplete filling reserve for the left ventricle.
Bedside transesophageal echocardiography is used daily in our unit as a routine hemodynamic evaluation in critically ill patients undergoing ventilation. Recently, systematic use of a multiplane transducer has given us the opportunity to record superior vena caval (SVC) dimensional changes during mechanical ventilation. We observed in several patients a partial vena caval collapse during tidal ventilation. Occurrence of this partial collapse suggested that, at this time, external pressure exerted by the

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Rank: 13
Score: 66.4764
Retrieved Text: The 50-1049 double channel tubing valve has two settings. The first setting allows exhaust air from the test subject to be routed to the atmosphere. The second setting connects the subject’s inspiratory tube to the gas supply bag and the expiratory tube to the gas collection bag. Residual volume, functional residual capacity and total lung capacity can also be tested by adding an additional 50-1049 tubing valve at the mouth of one of the bags.

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Rank: 14
Score: 66.09988
Retrieved Text: To describe the recommendations of the Pediatric Acute Lung Injury Consensus Conference for mechanical ventilation management of pediatric patients with acute respiratory distress syndrome.Consensus Conference of experts in pediatric acute lung injury.The Pediatric Acute Lung Injury Consensus Conference experts developed and voted on a total of 27 recommendations focused on the optimal mechanical ventilation approach of the patient with pediatric acute respiratory distress syndrome. Topics included ventilator mode, tidal volume delivery, inspiratory plateau pressure, high-frequency ventilation, cuffed endotracheal tubes, and gas exchange goals. When experimental data were lacking, a modified Delphi approach emphasizing the strong professional agreement was used.There were 17 recommendations with strong agreement and 10 recommendations with weak agreement. There were no recommendations with equipoise or disagreement. There was weak agreement on recommendations concerning approach to tidal volume and inspiratory pressure limitation (88% to 72% agreement, respectively), whereas strong agreement could be achieved for accepting permissive hypercapnia. Using positive end-expiratory pressure levels greater than 15 cm H2O in severe pediatric acute respiratory distress syndrome, under the condition that the markers of oxygen delivery, respiratory system compliance, and hemodynamics are closely monitored as positive end-expiratory pressure is increased, is strongly recommended. The concept of exploring the effects of careful recruitment maneuvers during conventional ventilation met an agreement level of 88%, whereas the use of recruitment maneuvers during rescue high-frequency oscillatory ventilation is highly recommended (strong agreement).The Consensus Conference developed pediatric-specific recommendations regarding mechanical ventilation of the patient with pediatric acute respiratory distress syndrome as well as future research priorities. These recommendations are intended to initiate

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Rank: 15
Score: 65.605446
Retrieved Text: From the Department of Pediatrics, G.S.V.M. Medical College, Kanpur 208 002, India.
Correspondence to: Dr. V.N. Tripathi, Professor, Department of Pediatrics, G.S.V.M. Medical College, Kanpur 208 002, India.
Mechanical ventilation is the cornerstone of present day pediatric intensive care. In recent years, this modality has evolved into a highly specialized discipline(1). From the "iron lungs" used in the past primarily to treat respiratory paralysis in poliomyelitis, modern day ventilators have evolved into micro-processor based sophisticated devices capable of a large number of functions with many alarms to make them as safe as possible for the patient. This article attempts to briefly outline the salient features of mechanical ventilation in pediatric practice.
The term mechanical ventilation refers to various artificial means used to support ventilation and oxygenation(2). They encom-pass all forms of positive pressure ventilation as well as ventilators capable of taking over the entire function of breathing. In order to decide the need for mechanical ventilation, as well as monitor a patient it is worthwhile to familiarize oneself with some common terms and abbreviations shown in Tables I and II.
Tidal Volume: This is the volume of air inspired or expired in each breath.
Functional residual capacity: It is a measure of the volume of the lungs at end expiration.
Inspiratory time (Ti) and Expiratory time (Te): Time allowed for inflow and outflow of the air-gas mixture.
I:E ratio: Ratio between inspiratory time and expiratory time.
Peak inspiratory pressure (PIP): Highest pressure reached during the inspiratory phase. It is guided by good chest excursions and air entry.
Mean airway pressure (MAP): It is the average

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Rank: 16
Score: 65.08343
Retrieved Text: Breathing Retraining in Asthma Management–I told you so!
In asthma management, complementary and alternative medicine is enjoying a growing popularity worldwide. This review synthesizes the literature on complementary and alternative medicine techniques that utilize breathing retraining as their primary component and compares evidence from controlled trials with before-and-after trials. Medline, PubMed, Cumulative Index to Nursing and Allied Health Literature and the Cochrane Library electronic databases were searched. Breathing retraining, a popular form of complementary and alternative medicine (CAM), is the subject of this review. You can read the entire article if you would like–don’t count on staying awake for the entire article!
It is reasonable for clinicians to offer qualified support to patients with asthma undertaking these breathing retraining techniques.
There was some evidence that beneficial effects declined with time if breathing techniques were not maintained.
Weiner et al., in three separate controlled trials, found that specific inspiratory muscle training using either an externally weighted device or a purpose-designed threshold inspiratory muscle trainer (HealthScan; NJ, USA) compared with ‘sham’ muscle training significantly increased inspiratory muscle strength as measured by maximal inspiratory mouth pressure at residual volume (PImax at residual volume). Whew what a mouthful!
The most recent of these studies that compared female to male asthmatics found that using the same training method to allow females to attain a PImax equal to that of males resulted in a significant and highly correlated decrease in both dyspnea score and medication use in the active intervention group only.
I am now beginning to use “The Breather” for both inspiratory/expiratory muscle training in patients with

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Rank: 17
Score: 64.946915
Retrieved Text: What are the 5 components of the respiratory unit?
What are the three factors of respiration that are measured with PFTs?
What is the normal Tidal Volume?
What is the functional residual capacity?
What is the vital capacity?
What is the expiratory reserve volume?
Which lung volume cannot be measured with an inspirometer?
What is the first thing to check with a PFT result?
What does spirometry measure? Is this a static or dynamic measure?
What is used to determine gas exchange?
What is DLCO? What is it used to assess?
Can spirometry be used to definitively diagnose restrictive lung disease?
What are the three major factors that may affect the accuracy of spirometry?
What position must the patient be in to properly evaluate PFTs?
What happens to the lungs as we age?
Where is the FEV1 on a normal time-volume curve?
What part of a PFT is used to assess whether or not there is an obstruction to airflow? What value of this is characteristic of an obstruction to airflow?
What value of a PFT determines the severity of an obstruction to airflow? What values indicate mild, moderate, and severe?
What happens to the flow volume loop with an obstructive disease?
What happens to the FVC plateau on the time-volume exhaled curve with an obstructive disease? What about the FEV1?
What happens to the FVC plateau on the time-volume exhaled curve with an restrictive disease? What about the FEV1?
Sequential FVC measurements should be within what value of each other to be considered good quality?
How can you determine that quality of the breath in a PFT (time vs volume exhaled curve)?
What are the characteristics of the

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Rank: 18
Score: 63.898285
Retrieved Text: Zimmerman D, Junker C. Zimmerman D, Junker C Zimmerman, Darin, and Christopher Junker.Mechanical Ventilation: Principles of Action. In: Freeman BS, Berger JS. Freeman B.S., Berger J.S. Eds. Brian S. Freeman, and Jeffrey S. Berger.eds. Anesthesiology Core Review: Part One Basic Exam New York, NY: McGraw-Hill; 2014. http://accessanesthesiology.mhmedical.com/content.aspx?bookid=974&sectionid=61587243. Accessed April 23, 2019.
Zimmerman D, Junker C. Zimmerman D, Junker C Zimmerman, Darin, and Christopher Junker.. "Mechanical Ventilation: Principles of Action." Anesthesiology Core Review: Part One Basic Exam Freeman BS, Berger JS. Freeman B.S., Berger J.S. Eds. Brian S. Freeman, and Jeffrey S. Berger. New York, NY: McGraw-Hill, 2014, http://accessanesthesiology.mhmedical.com/content.aspx?bookid=974&sectionid=61587243.
Mechanical ventilation utilizes positive-pressure devices to improve oxygen (O2) and carbon dioxide (CO2) exchange. There are two main goals of mechanical ventilation: (1) maintain appropriate levels of arterial O2 and CO2; and (2) reduce the patient’s work of breathing. Mechanical ventilation is a supportive intervention that does not treat the underlying disease process.
Positive-pressure ventilation can be administered with an endotracheal tube (ETT) or noninvasively with a mask. Noninvasive management can be used for patients who have a nonobstructed airway, a preserved respiratory drive, and protective airway mechanisms intact. Invasive airway management is required if there is acute airway obstruction, inability to handle secretions, loss of protective airway reflexes, or respiratory failure that is refractory to noninvasive positive- pressure ventilation with persistent hypoxemia and hypercapnia.
Mechanical ventilation can be used to ensure a controlled airway for patients who require sedation, such as during surgical procedures, or to tolerate resuscitation and life support. Other goals include oxygenation, minute ventilation (MV) and pH control,

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Rank: 19
Score: 63.5941
Retrieved Text: The EMMS head-out plethysmography system can be used in a variety of applications involving chronic studies. The animal is conscious and placed inside a head-out plethysmograph (eg. PLY 231). A latex rubber neck seal ensures that the thoracic chamber is airtight. Movement of the animal's chest as it breathes inside the plethysmograph is directly related to respiratory flow, and this is measured using a TPF 100 transducer across a pneumotachograph in the wall of the thoracic chamber. A number of parameters (such as tidal volume, breathing rate, inspiratory time and expiratory time) can be derived from the flow signal.

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Rank: 20
Score: 63.364605
Retrieved Text: Image: The Philips V60 Plus enhances patient outcomes with less invasive respiratory care therapies (Photo courtesy of Philips Healthcare).
A comprehensive patient ventilation solution integrates noninvasive ventilation (NIV) and high flow therapy (HFT) in a single device.
The Royal Philips (Philips, Amsterdam, The Netherlands) V60 Plus ventilator offers both NIV and HFT on the same ventilator, limiting disruption and saving time. Designed specifically for noninvasive modalities, the V60 Plus delivers NIV performance with advanced delivery technologies and alarms. Philips proprietary Auto-Trak technology automatically adapts to changing breathing patterns and dynamic leaks, and includes auto-adaptive leak compensation, inspiratory triggering, and expiratory cycling for patients with a range of respiratory support needs.
The V60 Plus includes HFT for patients in need of consistent and humidified oxygen when weaning from NIV; average volume assured pressure support (AVAPS), which targets tidal volume in a pressure-limited mode to provide extra reassurance, similar to volume-limited mode; pressure control ventilation (PCV), which can be used when full control of the patient’s breathing pattern is required; and continuous positive airway pressure (CPAP) with a C-Flex option that offers three levels of flow-based expiratory pressure relief.
HFT delivers respiratory gases at a high flow rate to assist patients’ own spontaneous breathing. It does this by creating positive pressure in the airways, keeping them open. The high flow rate improves the effective exchange of gases by delivering oxygen and removing carbon dioxide (CO2), making breathing easier and relieving the patients’ respiratory muscles. The respiratory gases can also be warmed and humidified to help clear secretions.

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Rank: 21
Score: 63.02026
Retrieved Text: 1) Fifty-three patients of good risk, aged between 24 and 64 years were utilized for this study. An analysis was made on respiratory-rate, -volume, tidal volume, expiratory CO(2)-content and blood CO(2)-content at F-O anaesthesia which was carried out in various mathodes; with 2% F-O for 25 minutes, or with 2% F-O for 5, 10 and 15 minutes followed by 1% F-O. One-half mg. of atropine was tried in some cases as preoperative medication. 2) In both cases of 2% F-O alone and 2% F-O followed by 1% F-O inhalation, an increased respiratory rate and, in contrast, a decrement of respiratory volume and markedly of tidal volume were observed. 3) Preoperative medication of atropine decreased such tendencies in grade compared with non-atropine group. It seems to be apparent that atropine preoperative medication acts against respiratory inhibition of Fluothane. 4) The changes of respiratory rate, -volume and tidal volume under 2% F-O anaesthesia can be slightly recovered at the switch over to 1% F-O anaesthesia. which is more noticed when atropine was used. The tidal volume, however, can not be recovered above the physiologically minimum level in any case. 5) The CO(2) content in expiratory air was observed to be increased as the anaesthesia was deepened, which was, to some extent, inhibited by atropine. The content in the end tidal air, however, always increased above the physiological level in all cases. 6) Although the blood CO(2) content was also increased by F-O anaesthesia, it was a little over the physiological limite of the variation. 7) Bennett assistor markedly

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Rank: 22
Score: 62.08443
Retrieved Text: Optimal resuscitation is the application of positive pressure to inflate the lungs and achieve maximum alveolar recruitment – without causing further damage.
Optimal resuscitation is the application of positive pressure to inflate the lungs and achieve maximum alveolar recruitment – without causing further damage (and while establishing Functional Residual Capacity (FRC)).
Infant T-Piece Resuscitation has the benefit of providing controlled and precise pressures to help prevent lung over-distension. These controlled pressures, Peak Inspiratory Pressure (PIP) and Positive End Expiratory Pressure (PEEP), are delivered more accurately when compared with a self-inflating bag.
All major resuscitation guidelines from around the world recommend the use of Infant T-Piece Resuscitation.
For more information on T-Piece Resuscitation, watch the videos of Professor Colin Morley talking about Key Elements of Resuscitation.
Roehr CC, Kelm M, Fischer HS, et al. Manual ventilation devices in neonatal resuscitation: Tidal volume and positive pressure-provision. Resuscitation. 2010 Feb;81(2):202-5. Epub 2009 Nov 17.
Roehr CC, Kelm M, Proquitte H, et al. Equipment and Operator Training Denote Manual Ventilation Performance in Neonatal Resuscitation. Am J Perinatol. 2010 Oct;27(9):753-8. Epub 2010 May 10.
Dawson JA, Davis PG, Kamlin CO, et al. Free-flow oxygen delivery using a T-piece resuscitator. Arch Dis Child Fetal Neonatal Ed. Sep 2007;92(5):F421.
Williams R, Rankin N, Smith T, et al. Relationship between the humidity and temperature of inspired gas and the function of the airway mucosa. Crit Care Med. 1996;24(11):1920-1929.
Te Pas AB, Walther FJ. Ventilation of very preterm infants in the delivery room. Current Pediatric Reviews. 2006;2(3):187-197.
Te Pas AB, Siew M, Wallace MJ, et al. Establishing functional residual capacity at birth: the effect of

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Rank: 23
Score: 61.748142
Retrieved Text: Ontogeny of respiratory control and pulmonary mechanics in newborn rabbits.
Maturation of the respiratory pattern and the active and passive mechanical properties of the respiratory system were assessed in 19 tracheotomized rabbits (postnatal age range: 1-26 days) placed in a body plethysmograph. With maturation both minute ventilation and tidal volume significantly increased, whereas respiratory frequency decreased. When normalized for body weight (kg) both the passive (Rrs X kg) and active (R'rs X kg) resistances of the respiratory system significantly increased with age, whereas the corresponding passive (Crs X kg-1) and active (C'rs X kg-1) compliances significantly decreased. At any given age R'rs X kg only slightly exceeded Rrs X kg, whereas C'rs X kg-1 was significantly lower than Crs X kg-1. Moreover, the maturational increases in Rrs X kg and R'rs X kg exceeded the corresponding decreases in Crs X kg-1 and C'rs X kg-1, resulting in significant age-related increases in both the passive (tau rs) and active (tau'rs) time constants of the respiratory system. Due to the age-related increases in tau'rs, producing a delayed volume response to any given inspiratory driving pressure, the relative volume loss obtained at any time during inspiration was greater in the maturing rabbit. On the other hand, because of concomitant compensatory changes in respiratory pattern, evidenced by increases in inspiratory duration with age, the end-inspiratory tidal volume loss in the maturing animal was maintained generally less than 10% at all postnatal ages. Thus maturational changes in respiratory pattern appear coupled to changes in the active mechanical properties of the respiratory system.

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Rank: 24
Score: 61.63617
Retrieved Text: Figure 1. Flow-volume curve demonstrating flattening of both the inspiratory and expiratory limbs consistent with extra-thoracic obstruction.
Figure 2. Video demonstrated the vocal cords essentially fixed in the adducted position during the inspiratory and expiratory cycle.
A 59-year-old morbidly obese woman with acute hypoxemic respiratory failure secondary to pulmonary emboli required emergency intubation. She was described by the anesthesiologist as having a difficult airway. The patient was liberated from the ventilator after two days. Following extubation she complained of hoarse voice and dyspnea. Physical exam revealed audible stridor. The upper airway was normal by CAT imaging. Flow-volume curve demonstrated marked flattening of both the inspiratory and expiratory limbs, consistent with a fixed extra-thoracic obstruction (Figure 1). Endoscopy revealed the vocal cords to be in the adducted position, with minimal movement throughout the respiratory cycle, consistent with bilateral vocal cord paralysis (Figure 2).
Traumatic intubation follows thyroid surgery as the most common cause of bilateral vocal cord paralysis (1). In a minority of patients spontaneous recovery may occur. Surgical treatment options include cordotomy or tracheostomy. Nocturnal BIPAP has been used in patients who decline surgery (2).
Charles J. Van Hook MD, Britt Warner PA-C, Angela Taylor MD, and Jacquelynn Gould MD.

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Rank: 25
Score: 61.393723
Retrieved Text: Inspiratory & Expiratory Filters, Stand, and O2 Hose.
The flexible Esprit Ventilator combines sophisticated design with easy-to-use features. This microprocessor-driven unit is easily upgradeable and offers a range of modes and breath types including volume control, pressure control, and fully integrated noninvasive ventilation.
The flexible Esprit Ventilator combines sophisticated design with easy-to-use features. This microprocessor-driven unit is easily upgradeable and offers a range of modes and breath types including volume control, pressure control, and fully integrated noninvasive ventilation. Because it has no need for wall air or compressors, and can be run on either a power, AC battery pack or an external battery, the Esprit's mobility and versatility make it ideal for use in any setting, from hospital to sub-acute care facilities.

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Rank: 26
Score: 61.286182
Retrieved Text: Figure 2. A machine in adaptive pressure control mode (top) adjusts the inspiratory pressure to maintain a set tidal volume. Adaptive support ventilation (bottom) automatically selects the appropriate tidal volume and frequency for mandatory breaths and the appropriate tidal volume for spontaneous breaths on the basis of the respiratory system mechanics and the target minute ventilation.
A mistake appeared in Figure 2 on page 418 in the July issue of the Cleveland Clinic Journal of Medicine (Mireles-Cabodevila E, Diaz-Guzman E, Heresi GA, Chatburn RL. Alternative modes of mechanical ventilation: A review for the hospitalist. Cleve Clin J Med 2009; 76:417–430). The graph of the parameters in adaptive support ventilation incorrectly states, “Target tidal volume set by operator.” It should say, “Target tidal volume set by the ventilator.” The corrected figure is shown.

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Rank: 27
Score: 60.96246
Retrieved Text: A method of ventilating a patient comprises initially determining the class of the lungs of a given patient, selecting a pressure or flowrate inspiratory waveform and other ventilatory parameters like inspiratory pause and inspiratory time, among others, appropriate for that lung class, and then ventilating the patient with the selected inspiratory waveform and other ventilatory parameters. New ventilation inspiratory waveforms are provided which have been found to be advantageous for certain lung classes.
This invention relates to systems for the artificial ventilation of patients, and, more particularly, to a classification scheme for different types of patients' lungs, a method of identifying lung classes, and, a method and apparatus for the delivery of ventilatory parameters including waveform, inspiratory time, inspiratory pause and tidal volume, among others, dependent upon the identified lung class.
The lungs can be characterized as a mass exchanger in which oxygen, anesthetics and/or medication are delivered through the alveoli to blood pumped from the heart, and carbon dioxide, and anesthetics during emergence, are removed from the blood for exhalation. The mass transfer rate and efficiency in either direction, i.e. removal or inflow of gaseous materials at the blood/gas interface, is dependent at least in part on the distribution of ventilation to each lung. In turn, mechanical factors such as compliance and flow resistance within the bronchi and the different regions of the lungs affect the distribution of pulmonary ventilation. The term "compliance" refers to the elasticity of the lungs, or their ability to expand and contract during an inspiration and exhalation cycle, and is the inverse

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Rank: 28
Score: 60.502224
Retrieved Text: Anaesthesia: Churchill's prepared Reference offers a realistic compilation of investigations to help within the daily scientific administration of the peri-operative and severely unwell sufferer, and the parturient.
In this quantity, the authors have integrated an abundance of diagrams, figures, and tables that they locate priceless in realizing a few of demanding situations and prerequisites often encountered during this sector of medication and it truly is to be was hoping that the amount will advisor clinicians within the analysis and administration of universal stipulations encountered each day during this quarter of perform. This publication isn't intended to exchange greater, extra whole textbooks, yet to enrich them and should be worthwhile on the bedside, within the place of work and for teaching.
Anaesthetists are confronted with an ever-growing physique of investigative and healing techniques and it truly is more and more tricky to take care of with the extensive spectrum of knowledge required for them to accomplish optimally in daily perform.
Respiration failure is a fancy disorder approach wherein the underlying affliction and healing measures engage. This e-book includes an intensive bibliographic assessment, concentrating on preventive and healing experiences, that was once methodologically standardized, with authors assessing and classifying reviews in line with statutes of evidence-based drugs.
This re-creation of the Care of the severely ailing Surgical sufferer (CCrISP) path handbook has been absolutely up-to-date and revised by way of a multidisciplinary workforce of surgeons and anaesthetists. It is still real to the unique goals of the direction: to motivate trainees to take accountability for seriously sick sufferers, to foretell and stop

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Retrieved Text: Positive Expiratory Pressure (PEP) is breathing against resistance, which can be performed either through a device or against pursed lips .
Some literature has described PEP as two types varying in pressure range low and high pressure PEP. Low pressure PEP ranges from 5-20cm H2O at mid-expiration, whereas high-pressure PEP ranges from 26-102cm H2O which is achieved by maximal inspiration followed by performing forced expiratory maneuver into PEP mask. Other sources have described PEP as a three airways techniques that has been developed based on expiratory resistance:- PEP, High Positive Expiratory Pressure (HiPEP), and Oscillatory Positive Expiratory Pressure (OscPEP).
Involves breathing against expiratory resistance to temporarily increase Functional Residual Capacity (FRC)and Tidal Volume (VT)accompanied by clearance techniques such as Forced Expiratory Technique (FET), huffing, and or coughing.
Involves breathing against resistance by augmenting expiratory flow using FVC.
Oscillating PEP is an airway clearance technique, where the person blows all the way out many times through a device. Commonly known by their brand names (Flutter®, Acapella®, AerobikA®, and RC-Cornet®), these types of oscillating PEP devices work in two ways. Firstly, they use resistance to make it more difficult during the breath out, like non-oscillating PEP devices. Oscillating PEP devices also create vibrations when a patient breathes out. The vibrations move mucus from the surface of the airways. After blowing through the device several times, the person will huff and cough to clear the mucus from the lungs.
An increase in FRC is attained by alteration of breathing pattern that is a product of a decrease in expiratory flow and an increase in

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Input Text: Answer the following question given this paragraph: 

38.3 Joints and Skeletal Movement The structural classification of joints divides them into bony, fibrous, cartilaginous, and synovial joints. The bones of fibrous joints are held together by fibrous connective tissue; the three types of fibrous joints are sutures, syndesomes, and gomphoses. Cartilaginous joints are joints in which the bones are connected by cartilage; the two types of cartilaginous joints are synchondroses and symphyses. Synovial joints are joints that have a space between the adjoining bones. The functional classification divides joints into three categories: synarthroses, amphiarthroses, and diarthroses. The movement of synovial joints can be classified as one of four different types: gliding, angular, rotational, or special movement. Gliding movements occur as relatively flat bone surfaces move past each other. Angular movements are produced when the angle between the bones of a joint changes. Rotational movement is the movement of a bone as it rotates around its own longitudinal axis. Special movements include inversion, eversion, protraction, retraction, elevation, depression, dorsiflexion, plantar flexion, supination, pronation, and opposition. Synovial joints are also classified into six different categories on the basis of the shape and structure of the joint: planar, hinge, pivot, condyloid, saddle, and ball-and-socket.


Q: The structural classification of joints divides them into bony, fibrous, cartilaginous, and synovial joints. the bones of fibrous joints are held together by fibrous connective tissue; the three types of fibrous joints are sutures, syndesomes, and what?

 Choices:

- gomphoses

- synchondrosis

- articular

- cartilaginous

A:

Target Text: gomphoses

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Retrieved Text: A joint is simply the joining of two or more bones. Normally a joint allows movement of the body to occur. Joints also provide support to the body. Muscles attaching to the bones via tendons provide the force or leverage to move one bone relative to another. Wrapping around the joint itself are ligaments that support and protect the joint. Inside the joints may be found synovial fluids or cartilage, or both, depending upon the type of joint and its function.
Fibrous joints, where the bones are held together by connective tissues. An example of this kind of joint is the joining of the plates of our skull. No movement is desired here so the joints are fibrous, held tightly together.
Cartilaginous joints, where the bones are held together by cartilage and allow slight movement. Examples of these kinds of joints are the pubic symphysis (where the two ends of the pubic bones are connected by cartilage), between the ribs and their connection to the sternum, and in the spine in the region between adjoining vertebrae. Slight movement is allowed in all these areas but large ranges of movement are not desirable.
Yoga does not try to increase the range of movement in all three kinds of joints; however, for a cartilaginous joint that has grown too tight, Yin Yoga can help to restore the normal range of movement. For the synovial joints, Yin Yoga definitely helps rebuild and even extend the current range of movement, depending upon the type of synovial joint we are targeting.

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Retrieved Text: Definition : Articular anomalies are the anomalies of joints.
Definition: A synovial joint, also known as diarthrosis , joins bones with a fibrous joint capsule that is continuous with the periosteum of the joined bones.
It constitutes the outer boundary of a synovial cavity , and surrounds the bones’ articulating surfaces.
The synovial cavity or joint is filled with synovial fluid.
Fibrous joints are connected by dense connective tissue, consisting mainly of collagen.
These joints are also called "fixed" or "immoveable" joints, because they do not move. These joints have no joint cavity and are connected via fibrous connective tissue. The skull bones are connected by fibrous joints.
UI:859 - Interphalangeal joint of toe - Gout tophus.
Tophi in Sesamoid Bone of Foot in gout by Ed Euthman.

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Retrieved Text: We, humans, are equipped with bones that help us to structure our body without wasting energy. Because when we are standing still or walking, the bones are structuring and providing rigidity to our body. If we don’t have bones in our body, then the body has to structure itself with muscles – wasting a lot of energy. Let’s learn how these bones are connected together ether to form the skeletal system.
Bones in the body of humans are connected together to form a system of bones called the skeletal system. The main job of the skeletal system is to provide a rigid structure on which whole of our body holds. There are various functions to the bones other than providing rigidity. Some of these functions are providing protection to the soft and delicate organs, such as the heart, lungs, and brain. The brain is protected in the cranium of the skull, whereas the heart and lungs are protected in the rib cage.
There are around 206 bones in the skeleton of the human body. These bones are connected together and with muscles of the body to perform movements. Bones are connected with other bones with tissues called ligaments. The muscles are connected with bones with another tissue called tendon.
Bones of the human body are mostly composed of minerals of calcium and water. On average, the bones contains 31% water and are mostly made of non-living tissue materials. There are various layers of a bone, which are outer layers, inner layer, and center. The outer layer of the bone,

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Retrieved Text: A joint is where two bones meet together, and some joints allow a large movement factor where as others are slightly movable, and some allow no movement. Immovable joints also known as fibrous are all joined together by very strong fibrous connective tissue, and that is why they are not there for movement, a good example of this would be the cranium. Slightly movable joints also known as cartilaginous joints have cartilage between the bones, which allow a small amount of movement and a good example of this would be the sternum and the clavical.
Movable joints are mostly known as synovial joints, and these allow great range of movement because they have synovial fluid which acts as a lubricant. b) Synovial joints will almost mainly be found in the appendicular skeleton as they are needed for greater range of movements in the arms and legs etc, and the cartilaginous joints will be mainly found in the axial skeleton as they are not needed as much for movement prepuces, and act more as protection and support.
There are six types of synovial joints, and they all have different (Figure 5 Synovial) ranges of movement as some have large amounts of movement and others only allow small amounts. Continued Ball and Socket: A ball and socket joint allows a huge range of movement, and can use such movements as flexion, extension, adduction, abduction, circumduction and rotation, and some examples of these would be found in the hip and shoulder.
This joint is very similar to a ball and socket joint

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Retrieved Text: Synovial joints have a synovial cavity between the articulating bones. This cavity is filled with synovial fluid that reduces friction at the joint, enabling the articulating bones to move freely.
Synovial joints are freely movable joints.
A formal medical term is 'diarthroses' but synovial joints are commonly described as simply 'movable' or 'freely movable'.
Most of the main joints of the appendicular skeleton (including the arms and hands, and the legs and feet) are synovial joints. This type of joint is important in many health sciences, not just medicine and nursing but also physiotherapy, sports sciences, occupational therapy, massage therapies and so on.
The basic structure of a synovial joint is shown in the diagram on the right. The main parts of synovial joints are labelled on the synovial joint diagram and described in the table below.
Some synovial joints are more complicated than others. An example of a simple synovial joint, e.g. a metacarpophalangeal (finger) joint, is shown above-right. More complicated synovial joints can involve more than two bones, might include sesamoid bones e.g. the patella in the knee joint, might include bursae, and possibly accessory ligaments. An example of a general (more complex) synovial joint follows after the table.
There are at least 2 bones forming each joint. An example of a simple synovial joint is the 3rd metacarpophalangeal (MCP) joint, which is formed by two articulating bones, the 3rd metacarpal and the 3rd proximal phalanx.
Periosteum is a tough white fibrous membrane that covers the outer surface of bones wherever their surface is not covered by articular cartilage - see

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Retrieved Text: The solid framework that supports the body is called the skeleton. The bones of the skeleton work as anchor plates and levels to allow a person to move. Bones also play an important role in other body systems. For example, blood cells develop in the fatty inner tissue (red marrow) of bones.
Bones are a type of connective tissue which is as strong as steel but extremely light. This tissue is made up of specialized cells and protein fibers. Bone constantly breaks down and rebuilds itself.
The adult human body has 206 bones. The bones in the arms are the most commonly broken bones, accounting for almost half of all adult broken bones. In children, the collarbone is the most common broken bone.
Bones are made up of calcium, sodium, phosphorous and other minerals, as well as a protein called collagen. Bones stop growing in length during puberty; however, bone strength and density change over the course of one's lifetime.
Not only do bones allow body parts to move and function as the human skeleton, they also serve to protect organs from the damage of impacts.
The human foot contains 26 bones.
The hand contains 54 bones.
The longest and strongest bone of the body is the thighbone, called a femur.
The smallest and lightest bone is called the stapes and is located in the middle ear.
The only bone not connected to another bone is the hyoid, which is a V-shaped bone located at the base of the tongue.
The central shaft of long bones contain a medullary canal or marrow cavity. This cavity contains

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Retrieved Text: Orthopedists specialize in the diagnosis, treatment, rehabilitation and prevention of injuries to and diseases of the musculoskeletal system - the network of bones, joints, ligaments, tendons, muscles and nerves that gives the body its shape and allows us to move.
Many of the problems orthopedists treat involve the joints, places in the body where two or more bones meet. Humans have three different kinds of joints: fibrous (in the skull), cartilaginous (in the spine) and synovial (the neck, shoulders, elbows, wrists, hands, hips, knees, ankles and feet). This last type is what we usually refer to when we say "joint." Ligaments connect bones to each other, and tendons connect muscles and bones.
These parts of our bodies can be damaged from a traumatic injury, disease, congenital disorder or the natural aging process. Commonly treated conditions include arthritis, back pain, carpal tunnel syndrome, bone fractures, sprains and strains, knee and shoulder problems, tendon and ligament tears, osteoporosis, sports injuries, and pediatric conditions such as club foot. Patients may be infants, adolescents, middle-aged or elderly.
The introduction of minimally invasive techniques has meant that many patients can be examined and treated through tiny incisions, minimizing the trauma of "open" surgery and allowing them to enjoy a faster recovery and return to regular activities.
Children with orthopedic conditions require special care that takes into consideration their bones, joints and muscles for effective treatment that does not affect the growth and development process. Our doctors are specially trained in the diagnosis, treatment and prevention of pediatric orthopedic conditions, and work together with parents and

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Retrieved Text: Natural Joint Pain Relief: Relieve Joint Pain Naturally with NO SIDE EFFECTS!
Oh to be young again with pain-free joints! However, if you are like many of us – your joints can be painful and that pain can affect your everyday life. So, what causes this pain and how can you get natural joint pain relief?
Do You Understand Your Joints?
There are many joints in our body. Everywhere our bones meet is a joint. We have 3 different types of joints in our bodies but 2 of them – fibrous and cartilaginous joints – don’t move much, if at all. The most common joint is the synovial joint. This joint moves and can cause serious pain for people. There are 6 different types of synovial joints that give the body the ability to move the way we do. Our elbows and knees are hinge joints. The pivot joint on the top of the neck allows one bone to rotate over another, ball and socket joints make up our hips and shoulders. The last 3 joints called saddle, condyloid and gliding make up the joints in our fingers and toes. What is common to each of these joints is they contain ligaments to anchor bones together, the end of the bones contains a smooth surface of cartilage and a capsule covers the entire joint. This capsule, surrounded by a synovial membrane, creates a cavity filled with fluid. This fluid contains water and nutrients to lubricate the joints and keep things moving smoothly. Joints also contain sacs of fluid called

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Retrieved Text: Human anatomy is the branch of science concerned with the structure and function of the body.
The human body is the dancer's instrument of expression. Understanding how the body works can help a dancer stay in shape, improve performance, increase confidence and add longevity to his or her performing career. It can also help a dancer avoid injury. If an injury does occur, knowledge of human anatomy can contribute to a safe process of healing and recovery.
The thoracic cavity is the space above the diaphragm. It encloses the heart and lungs within the ribcage, sternum (breastbone) and twelve thoracic vertebrae.
The abdominal cavity, which houses the abdominal viscera, begins below the diaphragm and ends at the top of the pelvis, at about waist level.
The pelvic cavity extends from the end of the abdominal cavity to the pelvic floor.
Organ: A group of tissues that perform a particular function. For example, the heart, lungs, liver and kidney are all organs.
Pelvic floor: A group of muscles that reach from the pubic bone back to the sacrum. One function of the pelvic floor is to support the internal organs.
Tissue: A group or collection of similar cells and their intercellular substance that act together to perform a particular function. The primary tissues are epithelial, connective, skeletal, muscular, glandular and nervous.
The muscular and skeletal systems are often grouped together and called the musculoskeletal system. This system's primary function is movement.
The central nervous system involves the brain and the spinal cord. It is the control centre of the nervous system.
The peripheral nervous system consists of

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Retrieved Text: The Biomechanics of Human Skeletal Articulations. In: Hall SJ. Hall S.J. Ed. Susan J. Hall.eds. Basic Biomechanics, 8e New York, NY: McGraw-Hill; . http://accessphysiotherapy.mhmedical.com/content.aspx?bookid=2433&sectionid=191509739. Accessed April 21, 2019.
. "The Biomechanics of Human Skeletal Articulations." Basic Biomechanics, 8e Hall SJ. Hall S.J. Ed. Susan J. Hall. New York, NY: McGraw-Hill, , http://accessphysiotherapy.mhmedical.com/content.aspx?bookid=2433&sectionid=191509739.
Categorize joints based on structure and movement capabilities.
Explain the functions of articular cartilage and fibrocartilage.
Describe the material properties of articular connective tissues.
Explain advantages and disadvantages of different approaches to increasing or maintaining joint flexibility.
Describe the biomechanical contributions to common joint injuries and pathologies.
The joints of the human body largely govern the directional motion capabilities of body segments. The anatomical structure of a given joint, such as the uninjured knee, varies little from person to person; as do the directions in which the attached body segments, such as the thigh and lower leg, are permitted to move at the joint. However, differences in the relative tightness or laxity of the surrounding soft tissues result in differences in joint ranges of movement. This chapter discusses the biomechanical aspects of joint function, including the concepts of joint stability and joint flexibility, and related implications for injury potential.
Anatomists have categorized joints in several ways, based on joint complexity, the number of axes present, joint geometry, or movement capabilities. Because this book focuses on human movement, a joint classification system based on motion capabilities is presented.
1. Synarthroses (immovable) (syn = together; arthron = joint): These fibrous joints can attenuate force (absorb shock) but permit little or no movement of the articulating

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Retrieved Text: Located in the lower torso, the pelvis is a sturdy ring of bones that protects the delicate organs of the abdominopelvic cavity while anchoring the powerful muscles of the hip, thigh, and abdomen. Several bones unite to form the pelvis, including the sacrum, coccyx (tail bone), and the left and right coxal (hip) bones.
Continued From Above... The ilium is the largest, widest, and most superior of the hip bones. When you place your hands on your hips, you can feel the curved ridge of the ilium known as the iliac crest. The narrow ischium is inferior to the ilium and is the bone, along with the coccyx, that you rest your body weight on while sitting. Anterior to the ischium is the pubis, the smallest of the hip bones. The ilium, ischium, and pubis meet in the center of the hip bone to form the deep, cup-like socket of the hip joint called the acetabulum.
The sacrum and coccyx also begin life as multiple bones before fusing. Five short, wide vertebrae fuse to form the wedge-shaped sacrum, while four tiny vertebrae fuse to form the coccyx.
The bones of the adult pelvis join together to form four joints: the left and right sacroiliac joints, the sacrococcygeal joint, and the pubic symphysis.
The sacroiliac joints form between the sacrum and the left and right ilium to form a tight junction capable of supporting the body’s weight and resisting the force of strong muscles. Although the sacroiliac joints are synovial joints, many strong ligaments and bony ridges on the sacrum and

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Retrieved Text: Shoulder pain occurs in and around the shoulder joints. In some cases, pain in the shoulders can be difficult to distinguish from neck pain. The shoulders, which connect the arms to the trunk (torso), are the most moveable joints in the body. This high level of mobility can cause the joints to be relatively unstable. Shoulder pain often occurs as a result of disease or injury that affects structures in the shoulder joint (e.g., tendons, ligaments, muscles, bones).
The shoulders are made up of bones, cartilage, muscles, tendons, and ligaments. The upper arm bone (humerus), collar bone (clavicle), and shoulder blade (scapula), which are held together by bands of connective tissue called ligaments, make up the shoulder joints. The bones in the shoulders do not provide much stability to the joint and are held in place by muscles, tendons, and ligaments.
There are two joints in the shoulder. The glenohumeral joint is a flexible ball-and-socket joint formed by the scapula and the head of the humerus bone. This joint, which allows the shoulder to move forward and backward and the arm to move in a circular motion, is also called the shoulder joint.
The acromioclavicular joint is a gliding joint located on the top of the shoulder. This joint is formed by a part of the scapula called the acromion and the clavicle.
Articular cartilage cushions the shoulder joint and fibrous cartilage (called the labrum) helps to stabilize it. Sac-like structures called bursae (singular is bursa) are located within the shoulder joints. Bursae contain synovial fluid, which lubricates the joints

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Retrieved Text: Some synovial joints also have a fat pad, which can serve as a cushion between the bones. Some synovial joints also have an articular disc meniscus , which can provide padding between the bones, smooth their movements, or strongly join the bones together to strengthen the joint. This decreases the probability of the head slipping out of the acetabulum dislocation. Most of the joints within the wrist and ankle, as well as those between the articular processes of adjacent vertebrae, belong to this group. This membrane is a thick osseofascial structure extending from the tibial periosteum to the fibula, nearly the entire length between the 2 bones. Myositis ossificans can result from an unresolved hematoma in cases with large hematoma formation, repetitive insult, or continued use following the initial contusion.
When the knee is locked, it is completely rigid and all ligament of the joint are taut. It is worth considering using mobilisations in your assessment process and reading the Initial Assessment section in Maitlands book Peripheral Manipulation. All you need to do is pass the quiz relating to this page in the Physiopedia member area. Rotation of the neck or body is the twisting movement produced by the summation of the small rotational movements available between adjacent vertebrae. This diagram can also be formulated as a by representing the links of the mechanism as vertices and the joints as edges of the graph. Physiotherapists are sometimes considered specialists in manual therapy but other professions such as Osteopaths, Chiropractors and Nurses employ manual therapy in treatment.
In this

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Retrieved Text: The pelvis is made up of a ring of three bones, the two iliac bones and the central sacrum, sandwiched in-between. In the front of the pelvis, the pubic symphysis attaches the ilium bones to each other. This pubic symphysis joint is very immovable due to heavy fibrous tissue joining these bones in a configuration called a syndesmosis.
In the back of the pelvis, the area where each ilium bone joins the sacrum is called the sacroiliac joint (SI joint). The sacroiliac joints are mirror images of each other. These joints are unusually complex in that they are made of two different types of joints combined into one.
The rear and inferior portions of the SI joint contains a tough fibrous section similar to the pubic symphysis. This portion of the SI complex binds the pelvis together. These tough fibrous bands prevent most motion.
The front and superior portion of this joint has some aspects of a regular joint like the hip and knee and is called the diarthrodial portion of the joint. Normally diarthrodial joints are designed to slide against each other without friction. The major difference in the diarthrodial sacroiliac joint is that this joint is made of two opposing bony surfaces that are irregular and interdigitate together-preventing motion.
The surfaces of this joint are covered by hyaline cartilage (the same substance that lines hips and knees) and have a thin capsule that encloses this cavity. The capsule is lined with synovial tissue-the tissue that makes the lubrication for this joint.
The SI joint does not act as a

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Retrieved Text: Together, the bones and muscles make up the musculoskeletal system.
A bone is classified by its shape. A bone is enclosed by a tough, fibrous, connective tissue covering called the periosteum. A joint is where a long bone contacts another bone and it is covered by a layer of cartilage.
The primary connective tissues of the skeleton are bone, cartilage, and dense fibrous connective tissue. All connective tissues contain cells separated by a matrix that contains fibers.
Bone tissue is strong because the matrix contains mineral salts, notably calcium phosphate. Compact bone is highly organized and composed of tubular units, by comparison spongy bone has an unorganized appearance. Bones contain yellow bone marrow, which contains a large amount of fat. The spaces of spongy bone are often filled with red bone marrow, a specialized tissue that produces all types of blood cells.
Cartilage is not as strong as bone, but it is more flexible because the matrix is gel-like and contains many collagenous and elastic fibers. There are three types of cartilage, all of which are associated with bones: hyaline cartilage, fibrocartilage, and elastic cartilage.
Ligaments bind bone to bone while tendons connect muscle to bone at joints, both of which are dense fibrous connective tissue.
Bones are composed of living tissues.
The bones of the human skeleton, except those of the skull, first appear during embryonic development as hyaline cartilage. The cartilaginous structures are then gradually replaced by bone, a process called endochondral ossification.
In the adult, bone is continually being broken down and built up again, a process called remodeling.
The functions of

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Retrieved Text: Overview of the Lower Limb. In: Morton DA, Foreman K, Albertine KH. Morton D.A., Foreman K, Albertine K.H. Eds. David A. Morton, et al.eds. The Big Picture: Gross Anatomy, 2e New York, NY: McGraw-Hill; . http://accessphysiotherapy.mhmedical.com/content.aspx?bookid=2478&sectionid=202021720. Accessed April 21, 2019.
. "Overview of the Lower Limb." The Big Picture: Gross Anatomy, 2e Morton DA, Foreman K, Albertine KH. Morton D.A., Foreman K, Albertine K.H. Eds. David A. Morton, et al. New York, NY: McGraw-Hill, , http://accessphysiotherapy.mhmedical.com/content.aspx?bookid=2478&sectionid=202021720.
The bones of the skeleton provide a framework that serves as an attachment for soft tissues (e.g., muscles). The bony structure of the gluteal region and thigh, from proximal to distal, consists of the pelvis, femur, patella, tibia, and fibula (Figure 34-1A). Synovial joints and fibrous ligaments serve to connect bones together.
A. Skeleton of the lower limb. B. Osteology of the os coxa (pelvic bone). C. Femur.
Articulations. The pelvic bones articulate posteriorly with the sacrum via the sacroiliac joints, and anteriorly with each other at the pubic symphysis.
Constituents. Each pelvic bone consists of three bones: ilium, ischium, and pubis.
Acetabulum. A large cup-shaped structure at the junction where the ilium, ischium, and pubis fuse. The acetabulum protrudes laterally for articulation with the head of the femur bone.
Obturator foramen. An opening formed by the ilium, ischium, and pubis.
The ilium is the most superior and the largest bone of the three components of the pelvis.
Iliac fossa. Attachment site for the iliacus muscle.
Iliac crest. A prominent, palpable crest between the ASIS and PSIS where numerous body wall and limb muscles attach; possesses a large amount of

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Retrieved Text: Flashcards For Bones, Joints, and Actions of the Human Body is an excellent study tool for students who want to learn the bones, joints, and joint actions of the body, and concepts of kinesiology.
This set includes 256 full-color cards that provide a fun, quick, and portable way to study. Also included is a booklet containing helpful study hints for learning this material.
The drawings, terminology, and page references match with those in Joe Muscolino’s popular text, Kinesiology, The Skeletal System and Muscle Function.
112 bone cards show all the bones, bony landmarks, and joints of the human body in real photographs instead of drawings! The front of each card contains the photograph of the bone; the back of each card has the names of all the bony landmarks to allow for self quizzing.
The joints are then covered again, this time with 48 cards containing drawings that clearly depict the bones and joint capsules and ligaments of the joints. The front of each card contains the illustration with lead lines and blanks. The back of each card has the names of all the structures depicted on the front, allowing for self quizzing; along with the structural and functional classifications of the joint and an interesting fact about the featured joint.
58 joint action cards contain photographs with the bones drawn into the photograph that show the joint actions of the body. shown on the front of the card, the plane in which the joint actions occur and their ranges of motion, and the reverse actions of the depicted joint actions.
As

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Retrieved Text: As a BJJ practitioner, taking care of your joints is essential for career longevity . Your joints are the area where two or more bones meet together. With its structure, it allows you to move your knees, ankles, hips, elbows, shoulders, and wrist in different directions. It bears your weight and gives stability to your body. Each joint has specialised functions to control the range of your motion where it is located.
There are three main types of joints in your body: fibrous or immovable, cartilaginous or partially movable, and the synovial or freely movable joint. In Jiu-Jitsu, you should be more concerned with your highly mobile synovial joint which is made up of bones, muscles, cartilage, ligaments, and the synovial fluid filling your joint cavity.
Pivot joint - the joint in your neck which allows for the rotational movement of your head to move side to side.
Hinge joint - enables you to bend your limbs which can be found in your elbows and knees. It allows for a swinging motion either to flex the bones closer to one another or farther apart.
Ball and socket joint - provides rotation such as the hip and shoulder joints.
Condyloid joint - gives you the range to twist and bend which can be found in the wrist and ankle.
Saddle joint - moves just like the hinge joint but with more range of motion. An example of a saddle joint is the thumb.
Gliding joint - or plane joint is associated with your wrists and ankles where the bones slide along beside one another

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Retrieved Text: Rheumatism meaning, information about rheumatism causes, symptoms, diagnosis, treatment with homeopathy medicine, or homeopathic treatment for rheumatism.
The word rheumatism is derived from the Greek word ‘rheuma’, which means a swelling. It refers to an acute or chronic illness which is characterized by pain and swelling of the muscles, ligaments and tendons, or the joints. The medical terminology for rheumatism arthritis is rheumatoid arthritis. Rheumatism arthritis is a chronic and painful disorder which can attack the joints on your arms and legs leaving them inflamed and swollen. Although rheumatism symptoms may often resemble those of another condition called osteoarthritis, one can spot a few differences between them. In rheumatism arthritis, the lining in the joints is inflamed while in osteoarthritis the painful condition is due to wear and tear of joints and ligaments. Left untreated, rheumatism arthritis would ultimately result in denuded bones and permanently distorted joints. Osteoarthritis, on the other hand, is a painful condition but may not cause any permanent damage.
Negatively affect outcomes of primary Rheumatic fever and contribute to emergence of valvular disease. The initial attack of activity I or III degree, pronounced carditis, active rheumatic process at discharge, recurrences, absence of year-round prophylaxis allow prognostication of valvular heart disease.
Early rheumatism symptoms may include persistent pain in the joints along with swelling.
• Apart from pain and swelling, if your joints are tender to the touch, you may suffer from rheumatism arthritis.
• Individuals suffering from rheumatism arthritis may also experience persistent fevers and chills.
• Fever may be accompanied by a feeling of fatigue.
• Swollen hands

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Retrieved Text: Hydrostatic skeletons: Found in creatures such as worms and jellies, hydrostatic skeletons are basically chambers filled with water. Animals with this skeleton type move and change their shape by squeezing their water-filled chambers — just like what happens when you squeeze a water balloon.
Exoskeletons: These are exactly what they sound like — skeletons on the outside of the body. You’re probably quite familiar with these hard exterior coverings because they’re found on crabs, lobsters, and many insects. Exoskeletons are rigid and can’t expand as animals grow, so animals must molt, or shed, their exoskeletons periodically. After an animal molts, its new exoskeleton is soft — as in a soft-shelled crab.
Endoskeletons: The most familiar of all skeleton types is the endoskeleton. After all, it’s the kind of skeleton you have. An endoskeleton exists within an animal’s body. The human endoskeleton is hard because it’s partially constructed of the mineral calcium. The endoskeletons of other animals may be more flexible — for example, the endoskeleton of a shark is made of cartilage, the same material that makes up the soft parts of your nose.
Animals with hydrostatic skeletons and exoskeletons are considered invertebrates, meaning they don’t have a backbone. Animals with endoskeletons, like you, are considered vertebrates because they have a backbone.
All vertebrate skeletons— whether they belong to humans, snakes, bats, or whales — developed from the same ancestral skeleton (which explains why you may notice similarities between your skeleton and that of your pet dog or cat). Today, these animals show their relationship to each other in part

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Retrieved Text: Radio-Carpal Joint is the wrist joint that lies in the middle of the lower end of radius and carpus. It is a synovial joint of ellipsoid variety.
The inferior surface of the lower end of radius and inferior surface of the triangular articular disc of inferior radio-ulnar joint together forms Proximal articular surface. This proximal articular surface is concave from side to side and almost elliptical in shape.
Distal articular surface is formed by the proximal surfaces of scaphoid, triquetral, and lunate bones. It is smooth and convex.
Although wrist joint is an articulation between forearm and hand, the medial bone of forearm — the ulna is excluded from this articulation by an articular disc.
In the neutral position of the wrist, only the scaphoid and lunate are in contact with the radius and articular disc; the triquetral comes into contact with the articular disc only in the full adduction of the wrist.
The pisiform bone also does not participate in this articulation because it acts primarily as a sesamoid bone to increase the leverage of the flexor carpi ulnaris and lies in a plane anterior to the other carpal bones.
Capsular ligament (joint capsule): It is the fibrous covering of the joint and is attached above to the distal ends of radius and ulna, and below to the proximal row of carpal bones.The synovial membrane lines the inner surface of the fibrous capsule and extends up to the margins of the articular surfaces.
Radial collateral ligament: It extends from the tip of styloid process of radius to lateral aspects of the scaphoid

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Retrieved Text: Tarsal coalition describes the complete or partial union of two or more bones in the foot.
This developmental fusion is commonly symptomatic when partially fused, leading to the pseudo-joint (cartilaginous or fibrous union) undergoing increased mechanical stress. This in turn leads to stress responses within the bones and ‘joint’ which may lead to the development of early osteoarthritis.
The following case demonstrates the utility of ultrasound to identify a fibrous midfoot coalition between the calcaneus and navicular.
A previous MRI of the patient clearly demonstrates the coalition and associated bone stress response, which was missed by the reporting radiologist at an alternative imaging practice.
Ultrasound is a reliable tool in identifying bony coalitions, with the mantra of ‘scan where the patient is sore’ often yielding excellent results.

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Retrieved Text: Many people believe they know how to lift properly and safely. They are then in disbelief when they injure their back during a "simple" lift. After getting a back injury from lifting, many people will comment, "but I even bent my knees!" Therefore, there must be more to safe lifting than just bending the knees.
There's more to safe lifting than bending at the knees.
Getting out of position during lifting can put a great deal of stress on the lower back muscles, and when the demand is too high on a muscle it can be injured. Too much stress can form tiny tears in a muscle, known as a muscle strain, which is a very common form of back injury.
This type of back injury can be quite painful, making it difficult to move the affected and surrounding area. When a back muscle is strained, it can even be painful to breathe normally. A back strain will typically heal, although it often takes a long time (a few weeks or months).
The intervertebral discs act like ball bearings and cushions between the vertebrae (bones) in the spine. The discs are comprised of fibrous rings, which can bulge and even break open, or rupture, when injured. A disc injury in the lower back can cause pain that may radiate down into the buttocks and/or leg.
There are many joints where bones meet bones in the back. Normally theses joints are quite capable of handling the stresses of lifting. However, improper lifting techniques, even with lightweight objects, can irritate these joints and

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Retrieved Text: These types of joints lack a joint cavity and involve bones that are joined together by either hyaline cartilage or fibrocartilage (). There are two types of cartilaginous joints. A synchondrosis is a cartilaginous joint where the bones are joined by hyaline cartilage. Also classified as a synchondrosis are places where bone is united to a cartilage structure, such as between the anterior end... The types of joints in the human body can be classified according to either the structure of the joint ( how the bones are attached together ) or the function of the joint (described in terms of the extent of possible movement of the bones forming the joint ).
Study aids. Related quizzes: Anatomical planes and directions, quiz 1 - Test your knowledge of the terms used to describe locations on the body; Body movements, quiz 1 - The anatomical terms used to describe the different types of movement of the body.

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Retrieved Text: Osteo Bi-Flex is the #1 Doctor recommended brand of Glucosamine Chondroitin for natural arthritis relief. Millions of Americans take this supplement daily to help rebuild, repair and renew joint cartilage that has naturally worn down.
Osteo Bi-Flex is the best Glucosamine Chondroitin supplement in the country for joint care. It is the #1 Doctor recommended brand*, working to rebuild and repair joint cartilage, helping you live pain free.
So how does Osteo Bi-Flex work to help synovial joints?
Osteo Bi-Flex works by providing the nourishment your joints needs to help rebuild cartilage, while lubricating and strengthening your joints.
Arthritis pain is because our joints suffer natural wear and tear, they are less able to maintain the supportive cartilage matrix surrounding the joints and bones.
Osteo Bi-Flex works repairing the cartilage on joint surfaces, allowing comfortable movement.
This formula is manufactured under the strictest standards for product purity and potency using naturally-sourced Glucosamine and Chondroitin.
Glucosamine is a major building block of joint cartilage, which helps to maintain structural integrity of joints and connective tissue.
Directions for Adult Use: Take four (4) Caplets Per Day with Food. As a reminder, discuss the supplements and medications you take with your health care providers.

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Retrieved Text: Collagen is an important protein source, providing the nutrients required for the many processes that take place in muscles and cells. Collagen comprises 30% of the body’s protein content and is the ‘glue’ that holds your body together – it’s the fibrous protein found in organs, eyes, muscles, skin, hair, nails, teeth, bones, blood vessels, joints, tendons, cartilage and throughout your entire digestive system.
‘Glow Mama’ is beneficial for moms post-pregnancy to rescue thinning hair, dull skin and brittle nails which is a problem experienced by many moms today as a result of change in hormones after child-birth.
While the main benefit of collagen peptide post-birth is to Enhance Hair, Skin & Nails there really is so much more to MOTHERKIND. Glow Mama collagen peptide powder than thicker hair, stronger nails, smoother skin and strong bones.
Repairs & replenishes to give you a healthy glowing mama body!
Supplements bones, joints & muscles to work at their best to support your growing preggy belly!

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Retrieved Text: A healthy joint is made up of various pieces and moving parts. Let’s break it down.
What? It’s hard, but smooth and strong, but springy. A solid layer of the stuff covers the ends of bones within the joint space.
Why? It’s one of the most important features of a well-functioning joint. Without it, the bones start to rub each other the wrong way. Which is a real pain. Literally.
What? Scientific types will want to know that it’s made mostly of sodium hyaluronate or hyaluronic acid. Less scientific types can just call it “lube”.
Why? Because that’s what it does – it lubricates synovial joints like knees, elbows and hips by oiling up the bones and cartilage linings.
So what? Too little fluid, and the joint becomes dry, stiff and inflamed (read: sore). This can lead to increased friction, reduced shock absorption and even erosion of cartilage, exposing bone to bone (read: extremely sore).
What? This protein is the reason you’re standing – or at least sitting up at your computer and reading this sentence.
Why? Because collagen is the principal structural protein in connective tissues like cartilage, tendons and ligaments, as well as in bones, skin, hair and nails. So it’s a part of almost every part of you.
So what? As you age and collagen production slows, your skin starts to wrinkle and your bones and joints start taking strain. Incidentally, Type II collagen specifically is the kind found in joint cartilage. Remember that for later.
What? It’s a natural glucose-based compound (glucosamine – no surprises there) that’s also found in all

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Retrieved Text: Living with back arthritis is a daily challenge, and obtaining successful treatment for back arthritis can be life-changing. If you are suffering from arthritis that affects your back, an experienced spinal surgeon can help you choose a treatment plan so that arthritis symptoms will not control your life.
There are two main types of arthritis that cause back pain – osteoarthritis, where joint cartilage breaks down slowly overtime due to aging and wear-and-tear, and rheumatoid arthritis, which is an autoimmune disease that impacts a patient’s joints and can progress rapidly. Osteoarthritis is much more common back pain culprit than rheumatoid arthritis, but both can occur.
Anyone can be afflicted with arthritis of the back, though adults over age 50 are most at risk. Those who have previously suffered a spinal injury or were born with a spinal defect are also more likely to develop back arthritis, as are overweight people.
Back arthritis can lead to other conditions, which in turn can themselves cause increased back pain. One such condition is ankylosing spondylitis, which is a type of inflammation that causes bone fusion of the joints in the back, resulting from fibrous ligaments transforming into bones that then grow together.
Another example of an arthritic back condition is spinal stenosis, which occurs when the spinal cord is narrowed due to bony vertebrae overgrowth and ligament thickening.
Most back pain associated with arthritis occurs in the lower back, since this portion bears the most weight. This type of arthritic back pain can also radiate to the neck, hip and pelvic joints.
Spinal surgeons can

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Retrieved Text: The elbow joint is made up of bone, cartilage, and ligaments. Muscles and tendons help the elbow joint move. Dr. Patel, can you tell us more about the anatomy of the elbow?
Sure, Major Spencer. The elbow is where the bone of the upper arm, called the humerus, meets the two bones of the forearm, called the radius and the ulna. There are actually two joints in the elbow. The ulnohumeral joint is the hinge between the humerus and the ulna that enables the arm to bend and straighten. The olecranon is the upper part of the ulna that cups the lower end of the humerus, called the distal humerus.
The radiocapitellar joint is where the humerus and the radius meet, allowing for rotation of the forearm so that the hand can be turned palm up or palm down. The radial head is the knobby end of the radius that rotates around the ulna. Fluid-filled sacs called bursal sacs provide cushioning and reduce friction in these joints.
Ligaments, which are tough, fibrous tissues that connect bone to bone, surround the elbow joint. The thicker ligaments on the inner and outer sides of the elbow, called collateral ligaments, hold the elbow joint together and prevent dislocation. On the inside of the elbow is the ulnar collateral ligament, or UCL. The radial collateral ligament and the lateral collateral ligament are on the outside of the elbow.
Several muscles and tendons cross at the elbow. The flexor/pronator muscles of the forearm and wrist begin at the elbow. The forearm tendons, often called extensors,

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Retrieved Text: Stiffness is a common complaint in some of the older patients we see at the clinic.
It is a symptom felt due to a natural aging process that brings about changes predominately affecting the joints and muscles.
The fluid that keeps our joints well lubricated may decrease, the cartilage in these joints therefore is closer together and may rub and start to erode (osteoarthritis) and minerals (like calcium) may deposit in and around some joints (calcification).
In muscles, lipofuscin (a ‘wear and tear’ pigment) and fat is deposited, muscles start to shrink and their fibres are replaced more slowly or are replaced by more fibrous tissue.
Rest assured this is a completely normal process of aging but there are many things you can do to help yourself feel less stiff as you age. Make sure you maintain a good level of appropriate exercise (aimed at strength, balance and flexibility), look after your posture, don’t spend too long in static positions, stretch, stay well hydrated and eat a balanced diet. Some people consider taking supplements.
Physical therapy, such as osteopathy, can be very useful in helping to maintain good range of motion in joints, stretch out tight muscles and break down fibrous tissue deposits. Many patients report feeling more mobile and able after a course of treatments.

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Input Text: Answer the following question given this paragraph: 

Mineral crystals that form when magma cools are usually larger than crystals that form when lava cools.


Q: Mineral crystals that form when magma cools are usually _______ than crystals that form when lava cools.

 Choices:

- larger

- smaller

- denser

- older

A:

Target Text: larger

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Retrieved Text: 1) How are igneous rocks formed?
Igneous rocks are formed from the crystallization of magma as it cools.
Lava is magma that flows out onto Earth’s surface.
3) What are extrusive igneous rocks?
Extrusive rocks are fine-grained igneous rocks that cool quickly on the Earth’s surface.
4) What are intrusive igneous rocks?
Intrusive rocks are coarse-grained igneous rocks that cool slowly beneath the Earth’s surface.
Magma is a slushy mixture of molten rock, gases, and mineral crystals.
6) Why is silica an important magma compound?
Because silica is the most abundant compound in magma, it has the greatest effect on magma characteristics.
The 3 classes of magma are basaltic, andesitic, and rhyolitic.
They are classified according to their silica content.
Rocks melt at temperatures between 800°C and 1200°C.
These temperatures are found in the upper mantle and lower crust.
Because different minerals have different melting points, not all parts of a rock melt at the same time. Thus, this partial melting is why magma is slushy.
When magma cools, it crystallizes in the reverse order of partial melting. Fractional crystallization is the process by which the first minerals to crystallize from magma are the last to melt during partial melting.
12) Name 4 properties by which geologists classify igneous rocks.
13) Describe the mineral composition of the 3 major groups..
When magma cools slowly beneath Earth’s surface, large mineral crystals may form. These are intrusive rocks.
Extrusive rocks have no visible grains because they are made from lava that cooled too quickly for crystals to form.
Porphyritic texture forms when slowly cooling magma suddenly cools rapidly.
This forms a rock with large, well-formed crystals surrounded by finer-grained

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Retrieved Text: How Do Extrusive and Intrusive Environments Differ?
With a background on how melts form and freeze, we can now introduce key features of the two settings intrusive and extrusive in which igneous rocks form.
Different volcanoes extrude molten rock in different ways. Some volcanoes erupt streams of low-viscosity lava that ﬂood down the ﬂanks of the volcano and then cover broad swaths of the countryside. When this lava freezes, it forms a relatively thin lava ﬂow. Such ﬂows may cool in days to months. In contrast, some volcanoes erupt viscous masses of lava that pile into rubbly domes. And still others erupt explosively, sending clouds of volcanic ash and debris skyward, and/or avalanches of ash tumbling down the sides of the volcano.
If magma stayed put once it formed, new igneous rocks would not develop in or on the crust. But it doesn't stay put; magma tends to move upward, away from where it formed. In some cases, it reaches the Earth’s surface and erupts at a volcano. This movement is a key component of the Earth System, because it transfers material from deeper parts of the Earth upward and provides the raw material from which new rocks and the atmosphere and ocean form. Eventually, magma freezes and transforms into a new solid rock.
Magma rises for two reasons. First, buoyancy drives magma upward just as it drives a wooden block up through water, because magma is less dense than the surrounding rock. Second, magma rises because the weight of overlying rock creates pressure at depth that literally squeezes magma

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Retrieved Text: Igneous rocks are formed when molten rock (magma) cools and solidifies, with or without crystallization, either below the surface as intrusive (plutonic) rocks or on the surface as extrusive (volcanic) rocks. This magma can be derived from either the Earth's mantle or pre-existing rocks made molten by extreme temperature and pressure changes. Over 700 types of igneous rocks have been described, most of them formed beneath the surface of the Earth's crust. The word "igneous" is derived from the Latin ignis, meaning "fire".
The Earth's crust is about 35 kilometers (22 miles) thick under the continents, but averages only some 7 kilometers (4.3 miles) beneath the oceans. It is made up of rocks which have a relatively low density, and beneath the crust there is the denser rock of the mantle, which extends to a depth of nearly 3,000 kilometers (1,860 miles). Most of the magma which forms igneous rocks is generated within the upper parts of the mantle at temperatures estimated between 600 to 1600 °C.
As magma cools, minerals crystallize from the melt at different temperatures (fractional crystallization). There are relatively few minerals which are important in the formation of igneous rocks. This is because the magma from which the minerals crystallize is rich in only certain elements: silicon, oxygen, aluminium, sodium, potassium, calcium, iron, and magnesium. These are the elements which combine to form the silicate minerals, which account for over ninety percent of all igneous rocks.
in some special circumstances they host important mineral deposits (ores): for example, tungsten, tin, and uranium, are commonly associated

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Retrieved Text: Earth is made up of rocks and minerals.
A rock consists of two or more minerals.
Minerals are made of one or more chemicals.
There are three types of rocks: igneous, sedimentary and matamorphic.
Igneous rocks are formed when volcanoes erupt and liquid rock, called magma, is forced to the surface. When magma cools slowly and hardens inside the Earth’s crust, it forms granite, a very hard rock. Most mountains are made of granite. Other igneous rocks include periodite, obsidian and pumice. Pumice is the only rock that floats.
Sedimentary rocks are formed over millions of years. Mountains are worn down by erosion, and rivers and streams wash bits of rock away. This sediment settles in layers at the bottom. Gradually the weight of the layers and mud in lakes and oceans turns into sedimentary rock.
Fossils are often found in sedimentary rocks. Fossils are animals or plants that have died and been quickly covered by sediments (rock and mud) usually on the bottom of a river or other water body. Sedimentary rocks include sandstone, limestone and shale. Over time lots of plants and animals are caught in the layers of sediment and become part of the rock, forming carbon which eventually turns into coal, natural gas or petroleum. These are called fossil fuels.
Metamorphic rocks are igneous or sedimentary rocks that have been changed by great heat or pressure due to the movement of the Earth’s crust. Marble is one example of sedimentary rock that has been changed into metamorphic rock.
Over time, the Earth changes a rock from one type to another.

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Retrieved Text: Describes how one type of rock can change into another type.
Earth has a dynamic system. Lithosphere floats on a molten mantle. Rocks are created and the re-melted in an ongoing process. There's no sample of rock unchanged since the Earth was formed. Molten magma cools and forms igneous rocks. Tectonic processes uplift the rocks exposing them to weathering process. Igneous rocks are broken down into granular material, that are transported and deposited to form sedimentary rocks (tectonic basins). Sediments buried and subjected to heat and pressure create metamorphic rocks. Heated sufficiently to melt forming magma.
WHAT MAGMA IS CALLED ONCE IT REACHES THE EARTH'S SURFACE.
A type of igneous rock that generally contains large crystals and forms when magma cools slowly beneath Earth's surface, Igneous bodies that have crystallized within the crust.
Eruption of magma and ash onto the Earth's surface where they cool to form lava flows and ash deposits., Extrusive Igneous rocks are formed on the surface of earth form lava. They have small or no crystals because they form quickly.
Describes metamorphic rocks that lack distinct layers or bands., Marble & quartzite are what type of metamorphic rock?
Force per surface area where the force is normal to the surface: measured in pascals.
Based on mineral composition and texture. Meta rocks are either foliated or non foliated. Foliated is when the crystals are arranged in bands, and non foliated has grains in random orientations.
sedimentary rock in which older rocks, unless disrupted, are on the bottom, this forms in layers with the oldest layer at the bottom.
Calcite(most common) precipitates out

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Retrieved Text: Explain how igneous rock is formed. Describe the difference between exclusive igneous rock and inclusive igneous rock.
Minerals grains, that grow and rearrange, but don't form layers are what type of rock?
Which set of rocks would most likely be formed from the eruption of material from a fissure vent?
rock is formed from the cooling of lava on Earth's surface.
lower in density than granitic rock.
high in iron and magnesium.
When a volcano erupts, liquid rock called lava flow from the surface. What type of rock is formed from cooled lava?
Melted rock cools and hardens to form .
What type of rock are most fossils found in?
the shells of small sea creatures.
pebbles and other rocks cemented together.
the remains of living things.
crystals left behind when water evaporated.
meteorites that fell to Earth.
melted rock material that cooled and hardened.
layers of sediment that were squeezed together.
This rock is most likely because it is .
Lava that cools quickly forms rocks.
Granite is formed as an igneous rock.
They are formed from sediments that collected in ocean beds.
They are formed from cooled magma or lava.
They are formed over many years of pressure and heat within Earth.
They are the hot lava the moment it is expelled from a volcano.
Igneous rock transforms to sediment by .
Plutons are bodies of rocks that form the ground.

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Retrieved Text: ROCKS AND MINERALS What is in a Rock? Rocks are made up of many tiny pieces of minerals. Even if you smash a rock into a hundred pieces, ALL those would still be all the same mineral. Breaking it into pieces would not change the rock’s makeup. What are Minerals? Minerals are natural, nonliving crystals. They come in many sizes, shapes, and colors which is how scientists tell them apart. Minerals can be identified by their physical properties such as: color, luster, hardness, and streak color. Color is obvious, but what are luster, hardness, and streak color? • Luster refers to the way surface of mineral reflects light. • The hardness of a mineral refers to how easily it can be scratched. • Streak color is a physical property of minerals, which refers to the color streak a mineral leaves when scratched against a surface. Scientists use all these characteristics of minerals to identify them in nature. Lesson Checkpoint: What are rocks made of? Types of Rocks There are several types of rocks, and each is formed in a different way. Sedimentary Rocks How do sedimentary rocks form? Erosion is the process of bits of rocks, sand, soil, and dead matter being moved by the wind, water, and gravity. All the eroded materials that eventually settle on land or at the bottom of a body of water are known as sediment. As layers of sediment pile up, the top layers of sediment press the bottom layers together. The weight and pressure from the top layers cause

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Retrieved Text: Crystals are a special kind of solid material where the molecules fit together in a repeating pattern. This pattern causes the material to form all sorts of unique shapes.
The process of crystal forming is called crystallization. Crystals often form in nature when liquids cool and start to harden. Certain molecules in the liquid gather together as they attempt to become stable. They do this in a uniform and repeating pattern that forms the crystal.
In nature, crystals can form when liquid rock, called magma, cools. If it cools slowly, then crystals may form. Many valuable crystals such as diamonds, rubies, and emeralds form this way.
Another way crystals form is when water evaporates from a mixture. Salt crystals often form as salt water evaporates.
What unique properties do crystals have?
Crystals can have very flat surfaces called facets. They can form geometric shapes such as triangles, rectangles, and squares. The shapes are a direct result of the type of molecules and atoms that make up the crystal. Smaller crystals and larger crystals that were formed of the same molecules and in the same method should have similar shapes.
There are seven basic crystal shapes, also called lattices. They are Cubic, Trigonal, Triclinic, Orthorhombic, Hexagonal, Tetragonal, and Monoclinic.
Snowflakes - Snowflakes are ice crystals that are formed high in the clouds when water freezes. They always have six sides or arms, but every one of them is unique.
Timing crystals - When an electric current is sent through some crystals they vibrate at a very precise frequency. Quartz crystals are used in watches and

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Retrieved Text: Granite is an igneous rock that injects, or intrudes, as magma into Earth’s crust and then cools. It consists of four main mineral compounds. Two of these are types of feldspar, a group of silica compounds that constitute the most abundant mineral group on Earth. Plagioclase feldspar is a compound of sodium and silica; potassic feldspar is a compound of potassium and silica. Granite also contains quartz, the second most abundant rock-forming mineral after feldspar. The fourth main mineral compound is mica, which in granite is a silica compound with a crystalline appearance resembling sheets of paper. Muscovite is mica with a high concentration of potassium. Biotite is mica with iron and magnesium. Each of these mineral groups weathers according to its own chemical properties.
Granite cools slowly within the Earth’s crust. Feldspar, quartz and mica crystals form during the cooling. Vertical and horizontal fissures form within the rock mass as it contracts. The fissures expand to larger fractures as the rock cools further.
Wind, water and ice denude the soil and Earth’s crust overlying the granite mass, exposing it to the atmosphere. The rock expands and contracts in reaction to changes in temperature. It shatters on the surface and the fractures widen to form crevices.
Hydrolysis is the chemical weathering of minerals by a mildly acidic water that forms when rains dissolves trace gases in the atmosphere. The reaction of feldspar minerals in granite with rainwater produces kaolinite, white clay known as “China clay” used in the production of porcelain, paper and glass. Kaolinite is most abundant over

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Retrieved Text: Recalling igneous rocks, the specific rock that forms from a given magma depends on the components of the magma, the temperature at which the magma cools, how quickly the magma cools and also the pressure at which the rock forms. As materials crystallize, the atoms form a structure that is most stable at the temperature and pressure of the environment.
The type of metamorphic rock that can form depends on the rock that is being metamorphosed as well as the amount of pressure and heat to which the rock is exposed. Since varied temperature and pressures will produce different minerals, the exact type of metamorphic rock produced depends on the grade (intensity) of metamorphism. The grade of metamorphism can most often be determined by the minerals present within the metamorphic rock and the type of rock formed.
Some of the more common metamorphic minerals include quartz, feldspar, biotite, muscovite, chlorite, garnet, tourmaline, calcite, and amphibole. The rock that has undergone change is called the parent rock. Parent rocks can be any of the three types of rocks: igneous, sedimentary, or even metamorphic rocks which can be metamorphosed again.
Metamorphism often occurs on two scales: contact and regional. Contact metamorphism occurs relatively locally, in areas adjacent to igneous intrusions or in areas that are in contact with hot water known as hydrothermal fluids.
Typically this kind of metamorphism is caused by moderate pressure and extreme heat that may last for a period of days to thousands of years. In cases of contact metamorphism, the most extreme metamorphism occurs at the contact

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Retrieved Text: Igneous Rock - Middle School Science Rocks!
Scientists tell us that the Earth began as a huge ball of molten material. As it cooled it solidified. The first that formed was Igneous Rock -- meaning formed from fire. It took a long time for the molten material to cool. As it was cooling, it was still hot enough for atoms to move around. These atoms combined with other atoms forming compounds. These compounds formed minerals.
A rock is an Aggregate (mixture) of minerals.
The Sedimentary rock is baked and forms Metamorphic rock. If there is too much heat the rock melts into magma. It will cool and form Igneous rock again.
Crystallization-- cooling; sometimes under pressure.
We end up with what we started with. We have gone around in a circle. This called the Rock Cycle.
In this lesson we will only talk about Igneous Rock.
Igneous rock comes from two sources --- Magma and Lava. Both are liquid rocks.
Magma: liquid rock containing many dissolved gases (found inside the earth).
The magma rises up from the mantle region of the earth; the temperature there is 1400ºC.
Radioactive rocks are present at the crust-mantle boundary. The radioactivity gives enough heat to melt the rock.
Magma moves upward along cracks in the crust. If it overflows onto the earths surface, it is called lava.
The magma cools slowly. The atoms come together to form compounds and minerals. A combination of minerals gives rise to different Igneous rocks.
When the magma reaches the Earth's surface as Lava, it cools fast. The atoms don't have the time to move around forming various

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Retrieved Text: On this page you will find background information about rocks and minerals.
What is meant by inclusions ?
What is meant by Hydro-Thermal Veins ?
What is double terminated Quartz ?
What is the difference between minerals and rocks ?
What are the different types of rock ?
Can one identify a mineral by its colour and what elements influence that ?
What is a crystal ? OR What are crystals ?
Q: What is meant by "inclusions" ?
This literally means that the piece has acquired an additional feature in its formation, for example some quartz will clearly show such inclusions of minerals, Black inclusions tend to be Tourmaline rods, Green Azurite and Gold/Rust shades Iron trying to infuse. They make for very interesting specimens.
Q: What is meant by Hydro-Thermal Veins ?
Many good specimens are obtained from mineral veins. High temperature fluids deposit minerals in cracks and fissures in rocks these are often called hydrothermal veins and are frequently worked as sources of ore, they often contain colourful specimens and good crystals. Sometimes weathered- out cavity linings called Geodes are lined with well-shaped crystals and many fine specimens of Amethyst occur in these. Many crystal formations occur in Hydro- thermal veins. The largest are not always the most spectacular and some of the smallest crystals are the most perfectly formed ones.
Q: What is double terminated Quartz ?
Most crystals have a single pointed end but in the case of Double terminated this simply means they have a point at both ends. See stock pictures "Double terminated Quartz" one of my exhibition pieces is exceptional as

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Retrieved Text: 2. Minerals – an Introduction 14 2.1 Definition of a mineral 14 2.1.1 Polymorphs 15 2.2 Properties of minerals 15 2.2.1 Crystal form, growth habit and twinning 16 2.2.2 Cleavage and fracture 18 2.2.3 Lustre 18 2.2.4 Colour 18 2.2.5 Streak 19 2.2.6 Hardness 19 2.2.7 Tenacity 20 2.2.8 Density 20 2.2.9 Other properties 20 what‘s missing in this equation?
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Turning a challenge

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Retrieved Text: Rhyolite is a usually light-colored, fine-grained extrusive igneous rock that is compositionally similar to granite. It often includes flow lines formed during the extrusion. Due to the high silica content, rhyolite lava is very viscous. It may have any texture from glassy to aphanitic to porphyritic. The mineral assemblage is usually quartz, sanidine and plagioclase. Biotite and hornblende are common accessory minerals.
Many rhyolites form from granitic magma that has partially cooled in the subsurface. When these magmas erupt, a rock with two grain sizes can form. The large crystals that formed beneath the surface are called phenocrysts, and the small crystals formed at the surface are called groundmass. It contains less than 5% phenocrysts, or mineral grains visible without magnification. The rest of the more than 95% of the rock consists of a ground mass too fine to discern without magnification. This texture is the result of the rapid cooling of extruded lava, which does not allow sufficient time for larger crystals to grow.
The mineralogical composition of rhyolite is defined as containing mostly quartz and feldspar with a total silica content of more than 68%. Quartz in rhyolite may be as low as 10% but is usually present in amounts of 25% to 30%. Feldspars often comprise 50% to 70% of rhyolite, with potassium feldspar present in at least twice the amount of plagioclase feldspar. Ferromagnesian, or dark, minerals are rare as phenocrysts, being mostly biotite when present. Trace accessory minerals may also include muscovite, pyroxenes, amphiboles, and oxides.
Eruptions of granitic magma are rare. Since 1900

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Retrieved Text: "Magmatic" redirects here. For other uses, see Magma (disambiguation).
Lava flow on Hawaii. Lava is the extrusive equivalent of magma.
Magma (from Ancient Greek μάγμα (mágma) meaning "thick unguent") is the molten or semi-molten natural material from which all igneous rocks are formed. Magma is found beneath the surface of the Earth, and evidence of magmatism has also been discovered on other terrestrial planets and some natural satellites. Besides molten rock, magma may also contain suspended crystals and gas bubbles. Magma is produced by melting of the mantle and/or the crust at various tectonic settings, including subduction zones, continental rift zones, mid-ocean ridges and hotspots. Mantle and crustal melts migrate upwards through the crust where they are thought to be stored in magma chambers or trans-crustal crystal-rich mush zones. During their storage in the crust, magma compositions may be modified by fractional crystallization, contamination with crustal melts, magma mixing, and degassing. Following their ascent through the crust, magmas may feed a volcano or solidify underground to form an intrusion (e.g., an igneous dike or a sill). While the study of magma has historically relied on observing magma in the form of lava flows, magma has been encountered in situ three times during geothermal drilling projects—twice in Iceland (see Magma usage for energy production), and once in Hawaii.
Most magmatic liquids are rich in silica. Silicate melts are composed mainly of silicon, oxygen, aluminium, iron, magnesium, calcium, sodium, and potassium. The physical behaviours of melts depend upon their atomic structures as well as upon temperature and pressure and composition.
Viscosity is

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Retrieved Text: The Island of Hawaii is the only island to have white, black and green sand beaches. The green sand beach is south of Volcano Village on Route 11. Turn left at the South Point Road (between mile markers #69 and #70). About 11 miles from the turnoff you will pass some abandoned buildings and come to a fork in the road. Continue straight ahead to South Point. This area is the recommended location in which to park your vehicle and there is no charge for parking. From the Kaulana Boat Launch, and keeping within sight of the shore, it is approximately 2 & 1/4 miles to the Green Sand Beach (1-hour hike, one-way). Plan to walk unless you are prepared with a 4WD vehicle. Once at this littoral cone, carefully choose the path to the beach. The green sand owes its color and name to a large deposit of a semi-precious gem called olivine, sometimes referred to as the “Hawaiian Diamond.” Papakolea Beach (Green Sands Beach) is located in a bay circled by Pu`u Mahana, a cinder cone formed over 49,000 years ago and associated with the southwest rift of Mauna Loa. Since its last eruption, the cinder cone has partially collapsed and been partially eroded by the ocean.
The cinder cone is rich in olivine, a silicate mineral containing iron and magnesium, also known as peridot when of gem quality. Olivine is a common mineral component of Hawaiian lavas and one of the first crystals to form as magma cools. Olivine is locally known as “Hawaiian

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Retrieved Text: Diatomite: (Diatomaceous Earth) is composed essentially of the siliceous cases or "frustules" of minute plants known as diatoms which inhabit fresh and salt water. It is a very light, porous substance, somewhat friable.
Dyke: A dyke is an intrusion of magma into a fissure, shouldering aside other pre- existing bodies of rock; a dyke is always younger than the rocks that contain it.
Limonite: A secondary mineral which would have filled the microscopic voids in tree tissues as they decayed replacing wood with mineral.
Pillow lava: This rock shape is most often the result of undersea volcano eruptions. When lava from these eruptions was cooled quickly by the ocean it formed pillow shapes: as the outside hardened and then filled and burst, the fresh molten lava within then spilled over to form another pillow.
Porphyritic: A rock that has a distinct difference in the size of the crystals, with at least one group of crystals obviously larger than another group.
Protolith: The original rock from which a given metamorphic rock is formed. For example, the protolith of marble is limestone.
Ring dyke: A ring dyke typically forms when an underground pool of hot molten rock drains away. The pool's roof then collapses, forming cracks. Molten volcanic rock is then squeezed through the cracks to form dykes, which are roughly circular. As the softer rock eroded the hard volcanic dyke rock on the sides remained.

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Retrieved Text: Basalt and related rock types (like andesite, dacite, etc.) are rocks that form when volcanoes erupt magma (lava) onto the surface of the earth and the magma cools.
Lava rocks are permeable and are great for absorbing the oil(s) of your choice.

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Retrieved Text: Igneous rocks, born from molten rock called magma, dominate the western portions of the Eno River. All igneous rocks originate deep in the Earth as magma that rises toward the Earth’s surface at temperatures ranging from 1,800 to 2,200 degrees Fahrenheit (°F) (1,000 to 1,200 degrees Celsius (°C)). Igneous rocks are separated into two main categories: intrusive and volcanic rocks. Intrusive rocks form when magma solidifies within the Earth’s crust. Volcanic rocks form when magma solidifies on top of the Earth’s crust on land or in water.
Magma that cools and solidifies before reaching the surface of the Earth forms intrusive igneous rocks. Intrusive rocks are also commonly known as plutonic rocks. The word plutonic comes from Pluto, the Roman god of the underworld. Plutonic rocks form bodies known as plutons. Intrusive rocks cool slowly since they are insulated by the surrounding earth. This slow cooling allows the chemical elements within the magma to organize themselves into individual crystals that are visible with the naked eye. Figure 5 shows an example of a circa 630 million-year-old intrusive rock from the Eno River area. East of Roxboro Road, in the Triassic basin, a relatively young intrusive rock called diabase is present. The diabase is around 200 million years old and is present as tabular-shaped bodies that either intruded the surrounding sedimentary rocks parallel to the existing layering as sills or cut across the existing layering as dikes (fig. 6).
Figure 5 - Example of a 630 million year old igneous intrusive rock of the Carolina terrane.	The rock is a

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Retrieved Text: This semi precious gemstone material is called Mahogany Obsidian because the red color is similar to the wood-mahogany.
This deep black Obsidian with blood red streaks is found in central Oregon.
These beautiful designer cabochons also have a chatoyant gold sheen effect. When rotated in bright light there is a golden flash of color!
This material is translucent and some of it actually looks banded or striped when lit with a back light.
Black Obsidian is a natural volcanic glass. This glassy, lustrous gemstone is found in lava flows. Obsidian is produced when lava cools very quickly. The lava cools so quickly that no crystals can form. The red coloration in Mahogany Obsidian is likely the result of trapped hematite.
Obsidian was named after a Roman- Obsius, who is said to have discovered it.
Obsidian cabochons have a hardness of 5 to 5.5.
Metaphysical Properties of Obsidian: Obsidian is said to be a very grounding stone, and very healing. It is said to dispel feelings of unworthiness, that can hold one back from achieving their full potential. It sharpens and focuses internal and external vision, and helps one get in touch with buried issues before they can explode.

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Retrieved Text: Shield Volcano: Mt Hood, OR.
Of the three classes of rock, igneous rock is the most plentiful. Igneous rock forms after a volcano explosion. Mt. Hood in OR has the classic shape of a shield volcano. The Latin word, ignis, means fire and igneous rock forms through the cooling and solidification of magma or lava, a hot molten or partially molten rock material.
Magma is a silicate liquid generated by partial melting of the upper mantle or the lower crust. Different environments of formation, and the cooling rates associated with these, create very different textures and define the two major groupings within igneous rocks: Volcanic or Plutonic.
Half Dome, Yosemite, CA a granite monolith.
Volcanic or extrusive rocks result from magma reaching the surface forming minerals such as pumice or basalt. Plutonic or intrusive rocks result when magma cools and crystalizes slowly within the Earth’s crust. A common example of this type is granite. An example of a granite monolith is Half Dome in Yosemite, CA.
Mt Mazama (of Crater Lake) erupted.
Volcanic rocks form when magma rises to the surface and erupt, either as lava or pyroclastic material forming minerals such as pumice or basalt. The rate of cooling of the magma is rapid, and crystal growth is inhibited. Such rocks are termed extrusive rocks. An example is “Pumice Castle” made of pumice that hardened in the vent of Mt. Mazama at Crater Lake in OR. Volcanic rocks are characteristically fine-grained. Their texture is classified as “aphanitic” rock. Volcanic rocks often exhibit structures caused by their eruption, e.g. flow banding (formed

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Retrieved Text: The worksheets found on this page help students learn how to identify rocks and minerals. We also look at the rock cycle.
We often forget the importance of rocks and minerals in our daily lives. Rocks form in nature and they are created three different ways. Igneous rock is formed when the Earth’s molten layers (magma) cools and forms a hard rock. Sedimentary rock takes time to form. As the layers of the Earth settle and form sediment, the rock layer forms. Metamorphic rock starts out as one of the other two and undergoes a great deal of heat and pressure. Whenever tectonic plates collide, you will find a bunch of metamorphic rock in its path.
You will find worksheets that teach you how to create crystals, classify rocks, label soil layers, and identify the rock cycle.
Crystals are beautiful and people have long been fascinated by their wide variety of shapes. In this exercise, you will make your own crystal shapes.
One of the most important properties used to identify and classify a mineral is its hardness. The Mohs hardness scale measures a mineral's hardness using a simple scratch test to see what the mineral can scratch and be scratched by.
Minerals can be identified by carefully observing their physical characteristics.
There are three main types of rocks; igneous rock, metamorphic rock, and sedimentary rock. Use these three terms to answer the questions on this page.
Describes brightness of the light reflected from a mineral's surface.
Rocks can change from one type of rock into another due to heat, pressure, and weathering.
Soil and

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Retrieved Text: Question 1. Answer the following questions briefly.
(i) What are the three layers of the earth?
(ii) What is a rock?
(iii) Name three types of rocks.
(iv) How are extrusive and intrusive rocks formed?
(v) What do you mean by a rock cycle?
(vi) What are the uses of rocks?
(vii) What are metamorphic rocks?
(ii) A rock is a natural mass of mineral matter that makes up the earth’s crust.
Rocks can be of different colour, size and texture.
Igneous rocks also known as primary rocks.
(iv) When the molten lava comes on the earth’s surface, it rapidly cools down and becomes solid. Rocks formed in this way on the crust are extrusive igneous rocks.
Sometimes the molten magma cools down deep inside the earth’s crust. Solid rocks so formed are actually intrusive igneous rocks.
(v) One type of rock changes to another type under certain conditions in a cyclic manner. This process of transformation of the rock from one to another is known as the rock cycle. Let’s understand it through example—Igneous rocks change into sedimentary rocks. When the igneous and sedimentary rocks are subjected to heat and pressure, they change into metamorphic rocks. The metamorphic rocks which are still under great heat and pressure meet down to form molten magma. This molten magma again can cool down and solidify into igneous rocks.
(vi) Hard rocks are used for making roads, houses and buildings. Stones are used in many games, such as seven stones (pitthoo), hopscotch (stapu/kitkit), Five stones (gitti).
(vii) When the igneous and sedimentary rocks are subjected to heat and pressure they change into metamorphic rocks.

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Retrieved Text: This image from the Grand Canyon comes to you from Schurs Astrophotography.
I like that they refer to the growing dark after sunset as the Earth’s shadow.
raised the money from private donors to have 12,000 specimens from Roosevelt’s African expedition preserved and shipped back to the U.S.
On recent travels, I’ve seen a lot of rocks and soils that are dark grey, purple, red, and ochre. All of these colors come from iron. This monograph explains how one element can cause so many colors, at least in sandstone: Rainbow of Rocks.
Here’s a quick link to a good explanation of igneous (“formed by fire”) rocks: Igneous Rocks: Formation and Classification, by by amelianavarro.
Briefly, igneous rocks are formed from melted rock. Higher water content makes it easier for rocks to melt.
Intrusive rocks harden inside the earth and tend to cool slowly, forming larger crystals.
Extrusive rocks harden on the surface or in air. Usually, it is volcanoes that extrude them as lava, ash, or flying rocks. Extrusive rocks may expand explosively and cool rapidly. They may even be cooled by sea-water.
Phaneritic rocks have large crystals that are easy to see without magnification, e.g. granite.
Aphaneritic rocks have small, sand-like crystals. They may feel smooth. An example is basalt. Their crystals are so small that the human eye cannot see them [easily?] without a lens.
Porphryitic rocks have both small and large crystals. One may impulsively assume that large crystals make them phaneritic, so looks can be deceiving. An example is andesite.
Glassy rocks always look shiny. They may feel smooth or greasy. An example

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Retrieved Text: LAB: HOW CAN MINERALS FORM FROM WATER? Name: Many minerals form from the cooling of magma, but minerals can also form from other processes. Hydrothermal minerals are formed by concentration of hot, aqueous solutions flowing through cracks and pore spaces in crustal rocks.
2002-08-16· The solutions involve rain water and/or water derived from cooling magma bodies< Gems crystallize from solution when it encounters open spaces such as cracks. As a result, 'veins' of minerals fill preexisting cracks.
How are minerals formed from magma?
Mineral Formation Lesson Objectives. Describe how melted rock produces minerals. Describe how hot rock produces different minerals. Explain how minerals form from solutions. Introduction Minerals form under an enormous range of geologic conditions.
Minerals such as emeralds or tourmaline need unusual elements, like beryllium (for emeralds) or boron (for tourmaline) Metamorphic gems. Metamorphic rocks are rocks changed by heat, pressure, and interaction with solutions.
2013-03-07· This list details the ten most toxic and potentially deadly minerals that crystalize in the Earth’s rocks, presenting a dangerously deceptive array of stony beauty. These rocks don’t have to be thrown to hurt you.
2015-01-22· 1 Mineral Formation & Classification Mineral Formation & Classification High School Duration 2 –3 classes and Museum visit Location Module Purpose Classroom and Gem & Mineral Hall Supplies See individual lessons Standards Science 3.c; 9.a.
2018-07-04· The 'IMA database of mineral properties' (rrufffo/ima) has 173 species with 'not an IMA approved mineral' tag, some are an intermediate member of a solid solution series, others are "recently" discredited minerals.
Minerals present in the magma crystallize at different temperatures when cooling. And

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Retrieved Text: “That is not granite.” I said firmly, brimming with 24-year old certitude. The salesperson gave me a look over his glasses, annoyed. In his hands was a sample of Black Pearl.
The salesperson softened and we had a lively conversation about stones from Norway, upstate New York, and other localities. While our approaches to stone came from different directions, we shared an absolute love for them.
Scenes like this probably unfold every time a geologist walks into a stone showroom.
To a geologist, granite is one specific type of stone. It’s a light colored, coarse-grained igneous rock. Thus, “black granite,” to a geologist, is an oxymoron akin to a “vegetarian steak.” There simply is no such thing.
But neither side needs to be right or wrong on this. Naming conventions for stones vary across different industries. Those who work in mining, gemstones, commercial stones, and geology all have their own language. And that’s okay. Everyone should use the names that make the most sense for their purposes. The stone industry needn’t start labeling slabs as granodiorite or monzonite just to make geologists happy.
In the natural stone industry, “granite” often means any hard stone that is not marble. Different dealers use the term granite slightly differently. For example, quartzite and sandstone are sometimes classified as granite. Ideally, the names of stone reflect what they actually are. The more precise the definition, the clearer it is for everyone: consumers, salespeople, architects, designers, and fabricators. That said, stones with the same traits can be lumped together for simplicity’s sake.
Perhaps the most useful definition

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Retrieved Text: One of the primary effects of plate motion is to put new material from deep in the earth’s mantle onto the surface of the earth, and at the same time, destroy old crust. This creation, modification, and destruction of the surface materials of the earth is called the rock cycle. However, before we begin our discussion of the rock cycle, let’s clarify a very important point: rocks and minerals are not the same thing! A mineral is a naturally occurring, inorganic, solid element or compound, with a definite composition or compositional range and a regular internal crystal structure. A rock is a solid, cohesive aggregate of one or more minerals or mineral materials.
The key difference between a rock and a mineral is the ‘regular internal crystal structure’ of a mineral. For example, Quartz is a mineral (SiO2), while Granite is a rock. If you were to look at a quartz crystal at the molecular level, the entire crystal would be made up of identical building blocks (SiO2 molecules). Granite, on the other hand is not homogenous. Therefore, one chunk of a piece of granite, when viewed at the molecular level would appear very different from another chunk viewed at the molecular level because the first chunk might be a quartz crystal, while the second chunk might be another type of crystal.
Rocks are categorized by how they are formed. Rocks that are formed directly from liquid rock, or magma that wells up from deep in the earth are called igneous rocks. Rocks that form at, or just

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Retrieved Text: Explosive eruptions produce a mixture of volcanic ash and other fragments called tephra, rather than lava flows. The word lava comes from Italian, and is probably derived from the Latin word labes which means a fall or slide. The first use in connection with extruded magma (molten rock below the Earth's surface) was apparently in a short account written by Francesco Serao on the eruption of Vesuvius between May 14 and June 4, 1737. Serao described "a flow of fiery lava" as an analogy to the flow of water and mud down the flanks of the volcano following heavy rain.
The composition of almost all lava of the Earth's crust is dominated by silicate minerals, mostly feldspars, olivine, pyroxenes, amphiboles, micas and quartz.
Igneous rocks, which form lava flows when erupted, can be classified into three chemical types; felsic, intermediate, and mafic (four if one includes the super-heated ultramafic). These classes are primarily chemical; however, the chemistry of lava also tends to correlate with the magma temperature, its viscosity and its mode of eruption.
Felsic or silicic lavas such as rhyolite and dacite typically form lava spines, lava domes or "coulees" (which are thick, short lava flows) and are associated with pyroclastic (fragmental) deposits. Most silicic lava flows are extremely viscous, and typically fragment as they extrude, producing blocky autobreccias. The high viscosity and strength are the result of their chemistry, which is high in silica, aluminium, potassium, sodium, and calcium, forming a polymerized liquid rich in feldspar and quartz, and thus has a higher viscosity than other magma

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Retrieved Text: Andesite: The specimen shown is about two inches (five centimeters) across and has a porphyritic texture.
Igneous rock composition chart: This chart shows that andesite is typically composed of plagioclase, amphiboles, and micas; sometimes with minor amounts of pyroxenes, quartz, or orthoclase.
Andesite is the name used for a family of fine-grained, extrusive igneous rocks that are usually light to dark gray in color. They often weather to various shades of brown, and these specimens must be broken for proper examination. Andesite is rich in plagioclase feldspar minerals and may contain biotite, pyroxene, or amphibole. Andesite usually does not contain quartz or olivine.
Andesite is typically found in lava flows produced by stratovolcanoes. Because these lavas cooled rapidly at the surface, they are generally composed of small crystals. The mineral grains are usually so small that they cannot be seen without the use of a magnifying device. Some specimens that cooled rapidly contain a significant amount of glass, while others that formed from gas-charged lavas have a vesicular or amygdaloidal texture.
Stratovolcanoes: Pavlof Volcano (right) and Pavlof Sister Volcano (left) are a pair of symmetrical stratovolcanoes built of andesite flows and tephra on the Alaska Peninsula. Pavlof Volcano is one of the most active volcanoes in Alaska. Photo by T. Miller, United States Geological Survey.
Andesite and diorite are common rocks of the continental crust above subduction zones. They generally form after an oceanic plate melts during its descent into the subduction zone to produce a source of magma. Diorite is a coarse-grained igneous rock that forms when the magma did

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Retrieved Text: If you want to get powder of silica, silica grinding machines are needed in silica sand . ball mill for silica grinding silica quartz separation and grinding machine. Ghana, Uae, Iran, Korea, Japan, Turkey, Kuwait, Saudi arabia, Australia, Thailand,.
Jiangxi Hengchang Mining Machinery Manufacturing Co., Ltd., Experts in Manufacturing and Exporting Ball Mill, Shaking Table and 1776 more Products. A Verified CN Gold Supplier on Alibaba.com.
Minerals and precious stones Earth's jewels Most minerals on Earth are formed when magma rises from the depths of the planet to the surface and then cools. Crystals form from chemical elements present in the liquid rock, somewhat like the way rain turns into snow crystals in the cold.
The 2019 Building Envelope Contractors (BEC) Conference is the must-attend event for more than 500 contract glaziers, industry suppliers and technical experts to connect and discuss trends that impact the glass and glazing industry.
Background. A straightforward and efficient method for the synthesis of pyranopyrimidine diones derivatives from the reaction of barbituric acid, malononitrile and various aromatic aldehydes using SBA-Pr-SO 3 H as a nanocatalyst is reported.
May 30, 2013Download Silica Interactive SoundBoard for free. I made this very simple soundboard to help me do my radio work a bit more smoother. Most of the open source soundboards I found were buggy and annoyed the crap out of me, so I decided to make my own.

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Input Text: Answer the following question given this paragraph: 

Each silicon atom has four valence electrons it shares with other silicon atoms in a crystal. A semiconductor is formed by replacing a few silicon atoms with other atoms that have more or less valence electrons than silicon.


Q: Each silicon atom shares how many valence electrons with other silicon atoms in a crystal?

 Choices:

- five

- ten

- four

- three

A:

Target Text: four

#### Retrieved Documents ####

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Retrieved Text: Semiconductors are utilized widely in electric circuits. As its name signifies, a semiconductor is a component which carries out electric power, but only partially. The conductivity of a semiconductor is someplace in between that of an insulator, that has basically no conductivity, and a conductor, that has basically complete conductivity. Many semiconductors are crystals made from specific components, many generally silicon.
To comprehend how semiconductors function, you should initially comprehend a little about how electrons are arranged in an atom. The electrons in an atom are arranged in layers. These layers are known as shells. The outer shell is known as the valence shell.
The electrons within this shell are the ones which form bonds with surrounding atoms. This type of bonds are known covalent bonds. Many conductors have only one electron in the valence shell. Semiconductors, however, generally have 4 electrons in their valence shell.
it is feasible for all the valence electrons to connect with valence electrons coming from other atoms if all the surrounding atoms are of the exact same type. The atoms organize on their own into structures known crystals while that occurs. Semiconductors are produced of such crystals, generally silicon crystals.
Right here, each circle stands for a silicon atom, and the lines in between the atoms stand for the shared electrons. Each of the 4 valence electrons in each silicon atom is provided one surrounding silicon atom. Hence, every silicon atom is bound with 4 other silicon atoms.
Pure silicon crystals aren’t all that effective digitally. If you present little quantities of other elements into

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Retrieved Text: Conversion of light energy in electrical energy is based on a phenomenon called photovoltaic effect. When semiconductor materials are exposed to light, the some of the photons of light ray are absorbed by the semiconductor crystal which causes a significant number of free electrons in the crystal. This is the basic reason for producing electricity due to photovoltaic effect. Photovoltaic cell is the basic unit of the system where the photovoltaic effect is utilised to produce electricity from light energy. Silicon is the most widely used semiconductor material for constructing the photovoltaic cell. The silicon atom has four valence electrons. In a solid crystal, each silicon atom shares each of its four valence electrons with another nearest silicon atom hence creating covalent bonds between them. In this way, silicon crystal gets a tetrahedral lattice structure. While light ray strikes on any materials some portion of the light is reflected, some portion is transmitted through the materials and rest is absorbed by the materials.
The same thing happens when light falls on a silicon crystal. If the intensity of incident light is high enough, sufficient numbers of photons are absorbed by the crystal and these photons, in turn, excite some of the electrons of covalent bonds. These excited electrons then get sufficient energy to migrate from valence band to conduction band. As the energy level of these electrons is in the conduction band, they leave from the covalent bond leaving a hole in the bond behind each removed electron. These are called free electrons move randomly inside the

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Retrieved Text: Pure semiconductors are relatively good insulators as compared with metals, though not nearly as good as a true insulator like glass. To be useful in semiconductor applications, the intrinsic semiconductor, pure undoped semiconductor must have no more than one impurity atom in 10 billion semiconductor atoms. This is analogous to a grain of salt impurity in a railroad boxcar of sugar. Impure, or dirty semiconductors are considerably more conductive, though not as good as metals. Why might this be? To answer that question, we must look at the electron structure of such materials in Figure below.
The crystal lattice in Figure below (a) contains atoms having four electrons in the outer shell, forming four covalent bonds to adjacent atoms. This is the anticipated crystal lattice. The addition of a phosphorus atom with five electrons in the outer shell introduces an extra electron into the lattice as compared with the silicon atom. The pentavalent impurity forms four covalent bonds to four silicon atoms with four of the five electrons, fitting into the lattice with one electron left over. Note that this spare electron is not strongly bonded to the lattice as the electrons of normal Si atoms are. It is free to move about the crystal lattice, not being bound to the Phosphorus lattice site. Since we have doped at one part phosphorus in 10 million silicon atoms, few free electrons were created compared with the numerous silicon atoms. However, many electrons were created compared with the fewer electron-hole pairs in intrinsic silicon. Application of an external electric

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Retrieved Text: semiconductor is like that of an insulator. The main difference is that the semiconductor has a much smaller energy gap EI/ between the top of the highest filled band (called the valence band) and the bottom of the vacant band just above it (called the conduction band). Thus, there is no doubt that silicon (Ell = 1.1 eV) is a semiconductor and diamond (Ell = 5.5 eV) is an insulator. In silicon-but not in diamond-there is a real possibility that thermal agitation at room temperature will cause electrons to jump the gap from the valence band to the conduction band. In we compared three basic electrical properties of copper, our prototype metallic conductor, and silicon, our prototype semiconductor. Let us look again at that table, one row at a time, to see how a semiconductor differs from metal.
silicon in which the portion has J.ee projecte4 ont8 a ,Jane; compare the figure with which represents the unit cell of the lattice in three lIimensions. Each SiliCORatom c contributes its pair of 3s electrons and its pair of 3p electrons to form a rigid two-electron covalent “nd with each ef its four nearest neighbors. (A covalent bond is a link between two atoms in which the atoms share a pair of electrons.) The four atoms that lie within the unit cell in show these four bonds. The electrons that form the silicon-silicon bonds constitute the 1’llle1¥’eHnjof the silicon s.mplt. U an e\ectrot\ is tom ftOm one of these ~ends so that it some free to wander throughout the

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Retrieved Text: According to Bohr’s atomic model, the electrons revolving around the nucleus are governed by a definite path and hence have a definite energy level so the electrons in an atom have well-defined energy levels.
When the atoms are brought close to each other, they begin to influence each other due to mutual interaction between them. This mutual interaction is more in case of outer shell than the inner shells.
If we take silicon as an element which is a semi-conduct with electronic configuration of 152 252 2P6 352 3P2. Since the crystal contains at least 1023 atoms per unit volume so there may be at least 1023 sub-levels which are created. These sublevels lie very close to each other and hence they are known as the energy band.
When separation is d1, the electrons in the outer-most shell of one atom do not interact with the electrons in the atoms the other due to large separation so, at this stage, each atom has its own specified energy level.
When separation is d2, the inter-atomic separation is less, so the electrons in the outermost shell start interacting with another due to which the modification of levels start (3s and 3p) levels, but still at this stage, energy gap occurs.
When separation is d3, inter-atomic separation reduces further and the independent 3s and 3p levels disappear. They are now distributed in a continuous manner, hence forming an energy band.
When separation is r, the atoms are at there actual inter-atomic separation due to which the energy band splits up into two levels with a

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Retrieved Text: Bonding models for methane, CH4. Models are NOT reality. Each has its own strengths and limitations.
Students know chemical bonds between atoms in molecules such as H2, CH4, NH3, H2CCH2, N2, Cl2, and many large biological molecules are covalent.
Students know how to draw Lewis dot structures.
Covalent compounds tend to form so that each atom, by sharing electrons, has an octet of electrons in its highest occupied energy level.
Covalent compounds involve atoms of nonmetals only.
Lewis structures show how valence electrons are arranged among atoms in a molecule.
Lewis structures Reflect the central idea that stability of a compound relates to noble gas electron configuration.
Carbon (and silicon) form four covalent bonds.

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Retrieved Text: A detector can be a mechanical, chemical, or electrical device that measures the change of a variable in its environment. In Atomic Absorption Spectroscopy, the amount of radiation that passes through a sample is measured and quantitatively described by transmittance. As light passes through a sample, power is attenuated as it is absorbed by the analyte in the sample. Transmittance, T, is the ratio of the source radiation’s power exiting the sample, P, to the source radiation’s power entering the sample, P0.
Transmittance can also be described as a percent, %T, when T is multiplied by 100. A large percent transmittance (approaching 100%) is characterized as a low analyte absorbance, whereas, a low percent transmittance (approaching 0%) characterizes a high analyte absorbance.
Absorbance, A, can also be used to describe the attenuation of electromagnetic radiation as it passes through a sample. Absorbance is a more common unit of measurement for AAS because of its linearity to analyte concentration with respect to Beer’s Law.
A photodiode is a photoelectric transducer that produces an electric signal, or current, I, which results from absorption of photons. Photodiodes consist of a reverse-biased pn junction in order to convert radiant power reaching the transducer, to a proportional current.
The pn junction consists of two types of semi-conductor material, p-type and n-type. Both p-type and n-type materials contain silicon crystal, which is a well-known, commonly used semiconductor. In a silicon crystal, each silicon atom is bonded to its neighboring atom by four electrons, forming covalent bonds.
To differentiate the p-type material from the n-type material, the silicon

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Retrieved Text: The inert or noble gases have a stable full outer shell of electrons which is why they are so unreactive. Which group of elements has a stable number electrons in the outer energy level. Periodic table of the elements. How many valence electrons are in an atom of chlorine.
R Another exception -- the transition metals. The elements are arranged by increasing order of atomic number. Elements whose atoms have the same number of electrons in outer energy levels are in the same family. Their arrangement is characterized by different energy levels and orbitals within these levels. How to Find the Maximum Number of Electrons That Can Occupy a Shell.
How does the number of electrons in outer energy levels to the position of an element in the periodic table. An exception to this rule is He Helium. How do valence electrons determine chemical properties. How many valence electrons are in a silicon atom. You can check these answers with the simple method if you like, but it does work out in any case.

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Retrieved Text: referred to as inert or inactive atoms. However, if the valence shell of an atom lacks the required number of electrons to complete the shell, then the activity of the atom increases.
Figure 1-7 - A typical crystal structure.
Figure 1-8 - A two-dimensional view of a silicon cubic lattice.
Silicon and germanium, for example, are the most frequently used semiconductors. Both are quite similar in their structure and chemical behavior. Each has four electrons in the valence shell. Consider just silicon. Since it has fewer than the required number of eight electrons needed in the outer shell, its atoms will unite with other atoms until eight electrons are shared. This gives each atom a total of eight electrons in its valence shell; four of its own and four that it borrowed from the surrounding atoms. The sharing of valence electrons between two or more atoms produces a COVALENT BOND between the atoms. It is this bond that holds the atoms together in an orderly structure called a CRYSTAL. A crystal is just another name for a solid whose atoms or molecules are arranged in a three-dimensional geometrical pattern commonly referred to as a lattice. Figure 1-7 shows a typical crystal structure. Each sphere in the figure represents the nucleus of an atom, and the arms that join the atoms and support the structure are the covalent bonds.
As a result of this sharing process, the valence electrons are held tightly together. This can best be illustrated by the two-dimensional view of the silicon lattice in figure 1-8. The circles

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Retrieved Text: John Robert Woodyard (1904 - 1981) a U.S. physicist invented "doping" to improve the performance of semiconductors. Doping means to insert impurities of foreign atoms (e.g. boron (p-type) and phosphor (n-type)) into the existing silicon crystal structure.
Semiconductors doped with donor impurities are called n-type, while those doped with acceptor impurities are known as p-type.
By adding an impurity of a valence-five elements - phosphorus - to a valence-four semiconductor in order to increase the number of free charge carriers. The purpose of p-type doping is to create an abundance of holes. In the case of silicon, a trivalent atom - is substituted into the crystal lattice.
Generally, the n-type layer is only some tenth µm thick (approx. 0.2 µm). The layer underneath with approximately 300µm thickness is p-doped positively with boron (i.e. 3 instead of 4 electrons in the outer shell).
It applies for all manufacturing processes, that doping with boron is already conducted during the production of blocks or ingots or poles respectively. The n-doping with phosphor is carried out in a later process step.

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Retrieved Text: Sol. 1 At room temperature for silicon crystal, we have Concentration of Silicon 5 x 1022 atoms/cm3 intrinsic carrier concentration (holes or electrons) = 1.5 1010 cm i.e. only 1 atom in about 1012 contributes a free electron (and also a hole) to the silicon crystal because of broken covalent bonds. When silicon is doped with donor atoms, n-type silicon is formed.

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Retrieved Text: HCP and CCP have equal ef ciency i.e., 74% of space is occupied and coordination number is 12. CCP arrangement has FCC lattice.
Coordination number is the number of nearest neighbouring points surrounding a particular lattice point (point may be atom, ions or molecules).
Packing ef ciency in simple cubic unit cell is 52.4%, in bcc arrangement is 68% and in fcc is 74%.
Unoccupied spaces in solids are called interstitial voids or interstitial sites.
* No. of octahedral voids = N.
Valency defect lowers the density of a crystal.
Interstitial defect increases the density of a crystal.
(i) Stoichiometric defect also known as intrinsic or thermodynamic defect. Ratio of cations and anions is the same in defective crystal as in ideal crystal.
defective crystal from the ideal crystal.
(iii) Impurity defect (due to presence of some other ions at the lattice sites).
Schottky defect arises due to missing of equal number of cations and anions from lattice sites in the crystalline solid of the type A+B- and it lowers and density of alkali metal halides, e.g., NaCl, KCl etc.
Frenkel defect is the combination of vacancy and interstitial defects. Cations leave their actual lattice sites and occupy the interstitial space in the solid. Density remains the same in Frenkel defect.
(i) Metal excess defect due to anion vacancies.
(ii) Metal excess defect due to presence of extra cations.
(iii) Metal deciency due to absence of cations.
F-Center : In metal excess defect, electrons are trapped in the anion vacancies which act as colour centres, e.g., NaCl gives yellow colour when heated in sodium vapour.
Doping is the process of increasing the

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Retrieved Text: As solar panels continue to increase in popularity, have you ever wondered how they actually work? Here is a detailed breakdown of what solar cells are and how they work to provide everyone's favorite green energy alternative.
Electrons inside of solar cells absorb energy from sunlight, travel along an external circuit where they expend excess energy to perform work, and return to an open slot in the cell at their original energy level. The solar cell repeats this cycle as long as light is available.
The large busbar and smaller fingers that make up the front contact are designed for a balance of optimal charge collection (extracting generated current) but minimal shading over the cell.
An anti-reflective layer gives light more opportunities to be absorbed inside of the cell instead of simply reflecting away. It’s also what gives the cell a distinctive dark blue color.
The thin top layer of phosphorous doped silicon is called the “emitter”.
The thicker boron doped layer of silicon is called the “base”.
The rear contact is a thin, solid layer of conductive metal (e.g. aluminum).
The refinement process for silicon produces large ingots called crystals . These crystals are cut into many wafers . A common source wafer diameter for solar applications is about 6 inches (150mm). To maximize the amount of cells that can fit in a solar panel but minimize valuable silicon waste, certain types of cells  are cut into a rounded square shape.
A unit of light is a packet of energy called a photon . Photons enter the solar cell and are absorbed

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Retrieved Text: – An element is defined as a substance which cannot be decomposed into other substances. The smallest particle of an element which takes part in chemical reaction is known as atom.
– All matter is composed of atoms which are infinitesimally small.
from the stand point of electrical conductivity, as conductors, semiconductors or Insulators .To be conductor, the substance must contain some mobile electrons that can move freely between atoms. These free electrons come only from the valence (outer) orbit of the atom Conductivity depends on the number of electrons in the valence orbit.
“The energy level of an electron increases as its distance from the nucleus increases. Thus an electron in the second orbit possesses more energy than electron in the first orbit, electrons in the third orbit have higher energy than in the second orbit and so on. It follows, therefore, that electrons in the last orbit will possess very high energy. These high energy electrons are less bound to the nucleus and hence they are more mobile. It is the mobility of last orbit electrons that they acquire the property of combining with other atoms. Further due to this combining power of last orbit electrons of an atom they are called valence electrons”.
Atoms with fewer than four valence electrons are good conductors.
Atoms with more than four valence electrons are poor conductors.
Atoms with four valence electrons are semiconductors.
Normally, the atoms are electrically neutral, that is, the number of electrons and protons are the same, cancelling each other’s electrical force. Atoms “stay together’ because unlike charges attract each

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Retrieved Text: · Instead of gaining and loosing electrons, carbon shares its 4-electrons with another element or carbon to form molecule.
· Covalent bonds are formed as a result of sharing of electrons. Example- H2, O2, N2. Covalent compounds have low melting point and boiling point due to small intermolecular forces.
· H2forms by sharing valence electrons (1 per atom of H) and produce single bond between two hydrogen atoms.
· O2 forms by sharing valence electrons (2 per atom of O) and produce double bond between two oxygen atoms.
· N2forms by sharing valence electrons (3 per atom of N) and produce triple bond between two nitrogen atoms.
· Methane, CH4is simple carbon compounds and used as a fuel on large scale and also a major component of CNG (Compressed Natural Gas). Methane formed due to sharing of 4 valence electrons of carbon with 4 hydrogen atoms.
Carbon have three allotropes i.e. Diamond, Graphite and fullerene.
Diamond formed due to rigid three dimensional structures of carbon atoms because each carbon atom bonded to another 4 carbon atoms. It is hardest substance.
Graphite formed due to presence of hexagonal array layers above one another, and layers of hexagonal arrays formed because each carbon atom bonded to another 3 carbon atoms with 2 single and 1 double bond. It is smooth, slippery and very good conductor of electricity.
Fullerenes (C-60) are also an allotrope of carbon in which carbon atoms are arranged in football like shape.
Carbon shows versatile nature because it has two characteristics features which are catenation and tetravalency. These both feature gives large numbers of compounds.
Catenation

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Retrieved Text: When an electron is free to assume higher energy states around an atom's nucleus (due to its placement in a particular "shell"), it may be free to break away from the atom and comprise part of an electric current through the substance. If the quantum limitations imposed on an electron deny it this freedom, however, the electron is considered to be "bound" and cannot break away (at least not easily) to constitute a current. The former scenario is typical of conducting materials, while the latter is typical of insulating materials.
Some textbooks will tell you that an element's conductivity or nonconductivity is exclusively determined by the number of electrons residing in the atoms' outer "shell" (called the valence shell), but this is an oversimplification, as any examination of conductivity versus valence electrons in a table of elements will confirm. The true complexity of the situation is further revealed when the conductivity of molecules (collections of atoms bound to one another by electron activity) is considered.
A good example of this is the element carbon, which comprises materials of vastly differing conductivity: graphite and diamond. Graphite is a fair conductor of electricity, while diamond is practically an insulator (stranger yet, it is technically classified as a semiconductor, which in its pure form acts as an insulator, but can conduct under high temperatures and/or the influence of impurities). Both graphite and diamond are composed of the exact same types of atoms: carbon, with 6 protons, 6 neutrons and 6 electrons each. The fundamental difference between graphite and diamond being that

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Retrieved Text: The key feature of conventional Photovoltaic PV (solar) cells is the PN junction. In the PN junction solar cell, sunlight provides sufficient energy to the free electrons in the n region to allow them to cross the depletion region and combine with holes in the p region. This energy creates a potential difference (voltage) across the cell.
When an external load is connected, the electrons flow through the semiconductor material and provide current to the external load.
Although there are other types of solar cells and continuing research promises new developments in the future, the crystalline silicon PV cell is by far the most widely used.
A silicon photovoltaic (PV) cell converts the energy of sunlight directly into electricity—a process called the photovoltaic effect—by using a thin layer or wafer of silicon that has been doped to create a PN junction.
The depth and distribution of impurity atoms can be controlled very precisely during the doping process. As shown in Figure 1, the thin silicon circular wafers are first sliced from an ingot of ultra-pure silicon and then the surface of the wafer is textured for better light absorption.
The circular wafer may be trimmed to an octagonal, hexagonal, or rectangular shape for maximum coverage when fitted in a module.
One commonly used process for creating an ingot is called the Czochralski method. In this process, a seed crystal of silicon is dipped into melted silicon. As the seed crystal is withdrawn and rotated, a cylindrical ingot of silicon is formed.
The silicon wafer is doped to create the PN junction structure. The

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Retrieved Text: We know from the periodic table Carbon atoms have 4 valence electrons on the outer shells.
According to the Octet Rule of Electron Configuration, this means the four are free to wonder and find opportunity to PAIR UP with other atoms.
That’s because The Octet Rule requires the valence shell or outermost shell of the atoms to have 8 electrons to become stable.
When two carbon atoms come together, they can each share 1 electron and form a single bond. That will leave three valence electrons from each atom to pair up with other electrons from other atoms they come in contact with.
The skeletal structure shows the type of bonding between elements.
Here’s a trick – if you draw a line through the middle of the carbon bonds, you should be able to work out exactly 4 bonds on each side, because each carbon atom has 4 bonding electrons which are the valence electrons.

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Retrieved Text: In chemistry, a compound is formed when atoms from two or more different elements form a chemical bond.
An ionic bond, for instance, involves the transfer of an electron from one atom to another. Essentially, one atom is gaining an electron while another atom is losing an electron.
Another type of bond- covalent- occurs when atoms share electrons.
In our daily lives, chemical bonds occur around us constantly. The rain (H2O) falling outside your window, the sugar (C12H22O11)in your coffee, and the carbon dioxide (CO2) you exhale are all examples of chemical bonds.
Hunter Hickox, a May 2018 PhD graduate in the Department of Chemistry, works at the fundamental chemical level to discover both unidentified compounds and unknown ways these compounds can form bonds.
Part of the Robinson research group led by Dr. Gregory Robinson, Hickox investigates the chemistry of main group elements. The most abundant elements on Earth, the group includes: Sodium (Na), Potassium (K), Calcium (Ca), Aluminum (Al), Carbon (C), Nitrogen (N), Oxygen (O), Sulfur (S), and Silicon (Si).
Most elements have a favored oxidation state that is primarily what exists in nature.
Generally, elements from the main group are in a positive formal oxidation state, which means they lack electrons. For example, in silicon tetrachloride, SiCl4, the silicon atom is in the plus four oxidation state, and each chlorine atom is in the negative one oxidation state.
The research group primarily focuses on synthesizing new compounds with low-oxidation state main group elements.
To create these low-oxidation state main group elements, Hickox works to perform reductions, or a lowering of the oxidation state.
In

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Retrieved Text: Electron dot structures, also called Lewis structures, are a graphical representation of the way electrons are distributed throughout a compound. Each element's chemical symbol is surrounded by lines, representing bonds, and dots, representing non-bonded electrons. When drawing an electron structure, your goal is to make each element's valence, or outer electron shell, as full as possible, without going over the maximum number of electrons for that shell.
Determine each element in the structure by looking at its chemical formula. For example, carbon dioxide's formula is CO2. Therefore it has one carbon atom and two oxygen atoms.
Look up each element on the Periodic Table. Note each group, or column number. This reflects how many valence electrons the element has. For instance, carbon is in group 4A and oxygen is in group 6A; therefore carbon has four valence electrons and oxygen has six.
Add the valence electrons of all the elements. This is the total number of electrons available for the dot structure. Since 4 + 6 + 6 = 16, there will be 16 electrons in carbon dioxide's Lewis structure.
Determine which element is the least electronegative, or has the weakest pull on the electrons, by looking on an electronegativity chart or by examining the element's position relative to the other elements on the Periodic Table. Elements generally increase in electronegativity from left to right and from bottom to top. Carbon is the least electronegative element in the compound, with a value of 2.5.
Place the least electronegative element in the center of the structure, then surround it with the other

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Retrieved Text: I would like to know the difference between Inorganic and Organic Chemistry from the atomic point of view. Thank you.
In the most simple terms organic chemistry is the study of carbon based compounds while inorganic chemistry is the study of everything else. The reason we treat carbon based chemistry separately is because the carbon atom provides the backbone for almost all compounds found in living things. There are very specific rules for the way carbon bonds with other atoms and we can understand most of the chemistry based on these few rules. Inorganic chemistry mostly deals with metals which have somewhat different rules regarding bonding. The reason for these differences on the atomic level has to do with the arrangement of the electrons. Carbon has four valence electrons (electrons in its outermost shell) which means it typically forms four bonds. Inorganic atoms have different numbers of valence electrons (depending on its position in the periodic table/atomic number) and the electrons are found in different shells. These electrons bond differently than they do in carbon.
Organic chemistry is the study of compounds made of carbon,particularly hydrocarbons (molecules made up of carbon and hydrogen atoms). Compounds studied in organic chemistry can also have nitrogen,oxygen, sulfur, phosphorus, silicon, chlorine, fluorine, and other halogens.Inorganic chemistry deals with basically all of the other elements.Sometimes when a compound has both organic and inorganic parts, it is classified as organometallic. A common example of this is a transition metal with organic ligands.Although most biological molecules are purely organic, organometallic compounds play an important part

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Retrieved Text: Silicon Detectors in Particle Physics.
(An introduction to semiconductor detectors).
How do we see the collisions?
•Look for B vertex and measure decay length – dist. between primary and secondary vert.
Ionization medium: gas, liquid or solid.
What makes silicon detectors so popular and powerful?
there is no long range order.
• Important parameter of a detector : signal to noise ratio (SNR).
• Large signal  low ionisation energy  small band gap!
• Low noise  very few intrinsic charge carriers  large band gap!
• Optimal material: Eg ≈ 6 eV. !
• Band gap small enough to create a large number of e-h+ pairs.
• Such a material exist, it is Diamond.  too expensive for large detectors!.
 Number of thermal created e+ h- pairs four orders of magnitude higher than signal!
How to detect a drop of water in the ocean ?
Remove the charge carrier  Depletion zone in reverse biased p-n junctions (DIODE)!
What are Si-diodes made of?
• Each atom shares 4 valence electrons with its four neighbors.
• As T increases some electrons jump the gap from VB to CB.
⇒ Fermi Level moves close to CB.
Holes are the majority carriers.
=> Fermi Level moves close to VB.
carries and is called the depletion region.
h+ are refilled to the depletion zone. The depletion zone becomes narrower.
• The current across the junction increases significantly.
h+ are pulled out of the depletion zone. The depletion zone becomes larger.
• Diffusion across the junction is suppressed.
• Dominated by thermally generated e-h+ pairs.
b) atoms of the detector  permanent changes (defects) in the detector bulk.
in an inter lattice space (Interstitial, I).
Charged particles create

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Retrieved Text: As a homeschooling mom, I think hands on activities make learning science so much more interesting and fun. I also think they help children to understand science in a more concrete way. Things like atoms and molecules are pretty hard for a young child to comprehend without something tangible to relate to. In this post, and in a series of posts that will follow, I want to share with you some ideas for teaching elementary and middle school aged children about chemistry.
Let’s start with atoms and molecules.
Atoms are tiny tiny particles that make up all matter. You can’t see them - in fact, they are so tiny that millions and millions of them can fit in the point of the very sharpest pencil. But eveything around us is made of millions and millions of atoms - our bodies, our homes, our pets, the trees, even the air we breathe! To help make this concept more concrete, take a look through a magnifying glass at an image in a book or a picture printed from your computer. This will work best with a magnifying glass that magnifies at 4X or higher.
What do you see? Can you see that the picture is made from many many tiny dots? When you look at the picture with just your eyes, you don’t see the dots, but the picture is really just a whole lot of tiny dots of color put together. Atoms are like this - only even smaller!
This is a fun activity for a group of children. You build

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Retrieved Text: Not all atoms within a neutral molecule need be neutral. An atom can have the following charges: positive, negative, or neutral, depending on the electron distribution. This is often useful for understanding or predicting reactivity. Identifying formal charges helps you keep track of the electrons.
Determining the appropriate number of valence electrons for an atom – This can be accomplished by inspecting the periodic table. The group number indicates the appropriate number of valence electrons for each atom.
Determining whether the atom exhibits the appropriate number of electrons – In the Lewis structure, determine whether some of the atoms show an unexpected number of electrons.
The formal charge on an atom can be calculated using the following mathematical equation.
Lewis structures also show how atoms in the molecule are bonded. They can be drawn as lines (bonds) or dots (electrons). One line corresponds to two electrons. The nonbonding electrons, on the other hand, are the unshared electrons and these are shown as dots. One dot is equal to one nonbonding electron. The valence electrons are the electrons in the outermost shell of the atom.
[Formal charge]H = 1 – (1/2) × 2 – 0 = 0 ⇒ This applies to each hydrogen. These hydrogens are all zero.
⇒ This molecule is neutral.
[Formal charge]c = 4 – (1/2) × 6 – 0 = 4 – 3 – 0 = +1 ⇒ This is a cation.
[Formal charge]c = 4 – (1/2) × 6 – 2 = 4 – 3 – 2 = -1 ⇒ This is a anion.

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Retrieved Text: A single grain of sand contains about 2.3 x 10^19 silicon dioxide molecules. That may seem like a lot, but that sand grain contains even more atoms than molecules, since each silicon dioxide molecule is made up of three atoms. Relationships exist between atoms, ions, molecules and compounds, but these entities also have significant differences.
Atoms are incredibly tiny particles that make up everything. If you could peek inside one, you'd see one or more tiny electrons orbiting a nucleus, the central location where larger protons and neutrons reside. Protons have positive charges, electrons have negative charges and neutrons are electrically neutral. Atoms themselves are electrically neutral when they contain the same number of electrons and protons. Each proton and neutron in an atom consists of three smaller particles called quarks.
An ion differs from a regular atom because it contains an unequal number of electrons and protons. If an atom loses electrons, it acquires a positive charge. Gaining electrons creates a negatively charged atom. An ion has reactivity and chemical properties that differ from a neutral atom. A spectacular display of ionic activity occurs when the sun's ultraviolet light hits gas molecules in a comet's coma creating an ion tail.
Larger than an atom, a molecule is a group of bonded atoms. Atoms can combine in various ways to form molecules and compounds. An element, such as gold, is composed of molecules of only one type of atom, while compounds have different types of atoms. You can tell how many atoms of each kind exist in a molecule

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Retrieved Text: what is a 'dangling bond'?
In chemistry, a dangling bond is an unsatisfied valence on an immobilized atom.
In order to gain enough electrons to fill their valence shells many atoms will form covalent bonds with other atoms. In the simplest case, that of a single bond, two atoms each contribute one unpaired electron, and the resulting pair of electrons is shared between both atoms. Atoms which possess too few bonding partners to satisfy their valences and which possess unpaired electrons are termed free radicals; so, often, are molecules containing such atoms. When a free radical exists in an immobilized environment, for example, a solid, it is referred to as an &quot;immobilized free radical&quot; or a &quot;dangling bond&quot;.
1. Specify the number of protons, neutrons, and electrons in the neutral atom copper-64.
2. what is the mass, in grams, of 150mL of liquid with a density of 1.4g/mL ?

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Retrieved Text: Science has come along way since Aristotle’s theory of Air, Water, Fire, and Earth. Scientists have identified 90 naturally occurring elements, and created about 28 others.
the entire universe. make up our bodies. and in fact. our world. alone or in combinations.Elements  The elements. our sun. .
.The most abundant element in the earth’s crust is oxygen.
Periodic Table    The periodic table organizes the elements in a particular way. Understanding the organization and plan of the periodic table will help you obtain basic information about each of the 118 known elements. you can predict with reasonably good accuracy the physical and chemical properties of the element. . For example. You can also predict what other elements a particular element will react with chemically. A great deal of information about an element can be gathered from its position in the period table.
Key to the Periodic Table  Elements are organized on the table according to their atomic number. usually found near the top of the square.  The atomic number refers to how many protons an atom of that element has. No two elements have the same atomic number.  The atomic number is unique to that element. .  For instance. hydrogen has 1 proton. so it’s atomic number is 1.
. but usually:      atomic number symbol atomic mass number of valence electrons state of matter at room temperature.What’s in a square?  Different periodic tables can include various bits of information.
Atomic Number   This refers to how many protons

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Retrieved Text: A covalent bond is formed between two non-metals that have similar electronegativities. Neither atom is "strong" enough to attract electrons from the other. For stabilization, they share their electrons from outer molecular orbit with others. An ionic bond is formed between a metal and a non-metal. Non-metals(-ve ion) are "stronger" than the metal(+ve ion) and can get electrons very easily from the metal. These two opposite ions attract each other and form the ionic bond.
Covalent bonding is a form of chemical bonding between two non metallic atoms which is characterized by the sharing of pairs of electrons between atoms and other covalent bonds. Ionic bond, also known as electrovalent bond is a type of bond formed from the electrostatic attraction between oppositely charged ions in a chemical compound. These kinds of bonds occur mainly between a metallic and a non metallic atom.
The covalent bond is formed when two atoms are able to share electrons whereas the ionic bond is formed when the "sharing" is so unequal that an electron from atom A is completely lost to atom B, resulting in a pair of ions.
Each atom consists of protons, neutrons and electrons. At the centre of the atom, neutrons and protons stay together. But electrons revolve in orbit around the center. Each of these molecular orbits can have a certain number of electrons to form a stable atom. But apart from Inert gas, this configuration is not present with most of the atoms. So to stabilize the atom, each atom shares half of its electrons.
Covalent bonding is

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Retrieved Text: Thinking in terms of overlapping atomic orbitals is one way for us to explain how chemical bonds form in diatomic molecules. However, to understand how molecules with more than two atoms form stable bonds, we require a more detailed model. As an example, let us consider the water molecule, in which we have one oxygen atom bonding to two hydrogen atoms. Oxygen has the electron configuration 1s22s22p4, with two unpaired electrons (one in each of the two 2p orbitals). Valence bond theory would predict that the two O–H bonds form from the overlap of these two 2p orbitals with the 1s orbitals of the hydrogen atoms. If this were the case, the bond angle would be 90°, as shown in [link], because p orbitals are perpendicular to each other. Experimental evidence shows that the bond angle is 104.5°, not 90°. The prediction of the valence bond theory model does not match the real-world observations of a water molecule; a different model is needed.
Quantum-mechanical calculations suggest why the observed bond angles in H2O differ from those predicted by the overlap of the 1s orbital of the hydrogen atoms with the 2p orbitals of the oxygen atom. The mathematical expression known as the wave function, ψ, contains information about each orbital and the wavelike properties of electrons in an isolated atom. When atoms are bound together in a molecule, the wave functions combine to produce new mathematical descriptions that have different shapes. This process of combining the wave functions for atomic orbitals is called hybridization and is mathematically

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Retrieved Text: Amora Gem and Diamond are related crystals.
Since most people are familiar with diamond, we can explain Amora Gem by starting with a pure diamond. By taking a pure diamond, which is 100% pure carbon, and then removing every other carbon atom and putting a Silicon atom in instead, we end up with an Amora Gem's atomic composition (50% Carbon, 50% Silicon).
Because Silicon is a larger atom, the 50% carbon atoms have to shift to make room, but after the carbon atoms make room, you now have an Amora Gem.
(Note that to do this and grow an Amora Gem requires very extreme heat. These temperatures are found only around large stars or in extreme growth chambers that create the star-like environment. Diamond itself would vaporize in these star-like conditions which is why Amora Gem was only made available on Earth recently).
The 50% Silicon atom composition is what gives Amora Gem superior fire, brilliance and lustre versus diamond. Silicon is larger than carbon, so it is better able to bend light, and light bending and dispersion (measured as refractive index and dispersion index) is what provides a gem's brilliance and fire.
This is similar to why lead crystal is more sparkly than regular crystal - the addition of the larger lead atoms provide more light bending versus pure crystal, and thus greater beauty.
Similarly, the shifting of the carbon atoms eliminates the 'seams' that are inherent in diamond. These seams, known as 'cleavage planes' are effectively atomic zippers - hit there and your resistance is only one carbon atom bond

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Input Text: Answer the following question given this paragraph: 

During sexual reproduction, two haploid gametes join in the process of fertilization to produce a diploid zygote.


Q: During what type of reproduction do two haploid gametes join in the process of fertilization to produce a diploid zygote?

 Choices:

- essential reproduction

- asexual reproduction

- sexual reproduction

- internal reproduction

A:

Target Text: sexual reproduction

#### Retrieved Documents ####

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Retrieved Text: Young to old. A life cycle?
Not in the biological sense. Life cycles describe the amount of DNA present at a specific stage or time in the life of an organism. Is there a haploid or diploid amount of DNA? That is the key question.
Sexual reproduction occurs in a cycle. Diploid parents produce haploid gametes that unite and develop into diploid adults, which repeat the cycle. This series of life stages and events that a sexually reproducing organism goes through is called its life cycle. Sexually reproducing organisms can have different types of life cycles. Three are represented in Figure below and described following sections.
Life cycles can vary in sexually reproducing organisms. Three types of sexual life cycles are shown here. Do you see how they differ? The letter n indicates haploid stages of the life cycles, and 2n indicates diploid stages.
The haploid life cycle is the simplest life cycle. It is found in many single-celled eukaryotic organisms. Organisms with a haploid life cycle spend the majority of their lives as haploid gametes. When the haploid gametes fuse, they form a diploid zygote. It quickly undergoes meiosis to produce more haploid gametes that repeat the life cycle.
Plants, algae, and some protists have a life cycle that alternates between diploid and haploid phases, known as alternation of generations. In plants, the life cycle alternates between the diploid sporophyte and haploid gametophyte. Spore forming cells in the diploid sporophyte undergo meiosis to produce spores, a haploid reproductive cell. Spores can develop into an adult without fusing with another cell.

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Retrieved Text: Individual organisms come and go, but, to a certain extent, organisms transcend time through producing offspring. Reproduction in animals occurs in two primary ways: through sexual reproduction and through asexual reproduction.
Now let's take a look at sexual reproduction.
In sexual reproduction, two individuals produce offspring that have genetic characteristics from both parents. Sexual reproduction introduces new gene combinations in a population.
In animals, sexual reproduction encompasses the fusion of two distinct gametes to form a zygote. Gametes are produced by a type of cell division called meiosis.
The gametes are haploid (containing only one set of chromosomes) while the zygote is diploid (containing two sets of chromosomes).
In most cases, the male gamete, called the spermatozoan, is relatively motile and usually has a flagellum. On the other hand, the female gamete, called the ovum, is nonmotile and relatively large in comparison to the male gamete.
There are two mechanisms by which fertilization can take place.
The first is external (the eggs are fertilized outside of the body); the second is internal (the eggs are fertilized within the female reproductive tract).
For example, many animals have estrous cycles that occur during certain parts of the year so that offspring can typically be born under favorable conditions. Humans however, do not undergo estrous cycles but menstrual cycles.

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Retrieved Text: Download "Rhizarians. Forams. Radiolarians. Cercozoans"
14 Figure 29.3 Exploring Derived Traits of Plants Charophyte algae lack the key traits of plants described in this figure: alternation of generations; multicellular, dependent embryos; walled spores produced in sporangia; multicellular gametangia; and apical meristems. This suggests that these traits were absent in the ancestor common to plants and charophytes but instead evolved as derived traits of plants. Not every plant exhibits all of these traits; certain lineages of plants have lost some traits over time. Alternation of Generations The life cycles of all plants alternate between two generations of distinct multicellular organisms: gametophytes and sporophytes. As shown in the diagram below (using a fern as an example), each generation gives rise to the other, a process that is called alternation of generations. This type of reproductive cycle evolved in various groups of algae but does not occur in the charophytes, the algae most closely related to plants. Take care not to confuse the alternation of generations in plants with the haploid and diploid stages in the life cycles of other sexually reproducing organisms (see Figure 13.6). Alternation of generations is distinguished by the fact that the life cycle Mitosis n Alternation of generations: five generalized steps 5 The spores develop into multicellular haploid gametophytes. n MEIOSIS 1 The gametophyte produces haploid gametes by mitosis. Gametophyte (n) Spore includes both multicellular haploid organisms and multicellular diploid organisms. The multicellular haploid gametophyte ( gamete-producing plant ) is named for its production by mitosis of haploid gametes eggs and sperm that fuse during

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Retrieved Text: Asexually reproducing organism can cope with a changing environment only through relatively rare spontaneous mutations that prove to be beneficial.
This process does not allow any variation in their population, though it is opposite in the case of sexual reproduction, which accepts variations in their population.
These offsprings are parents again give rise to new one.
No fertilization occurs during asexual reproduction. And due to which sexual reproduction is considered as the most fundamental aspect of evolution. These offspring are usually referred to as clones . Time is taken to complete Multiplication is very rapid and in lesser time. Starfish Regenerating its Legs Agamogenesis Any form of reproduction which does not involve male gametes is known as agamogenesis.
What is asexual reproduction? Types of asexual reproduction There are several different types of asexual reproduction but the most common ones include binary fission, budding, fragmentation and spores.
The number of offspring may vary from two to many and are genetically similar in asexual reproduction whereas the number of offspring produced are less in number comparatively which are genetically different from their parents.
There are specialized organs present in male and female gametes for sexual reproduction in plant and animals. If it continues to grow normally it can eventually become a baby. This combination of gametes is named treatment.
Both of these forms of reproduction occur in plants, fungi and animals however the specific form of reproduction will depend on the species . Puffballs Emitting Spores Sexual Reproduction of Plants Bryophytes like liverworts, mosses, and hornworts consist of motile sperms with flagella.
Fertilization takes place in

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Retrieved Text: Plants are multicellular organisms in the kingdom Plantae that use photosynthesis to make their own food. There are over 300,000 species of plants; common examples of plants include grasses, trees, and shrubs. Plants have an important role in the world’s ecosystems. They produce most of the world’s oxygen, and are important in the food chain, as many organisms eat plants or eat organisms which eat plants. The study of plants is called botany.
Plants are autotrophs; they produce their own food. They do so via photosynthesis, which is the process of making nutrients such as sugars from light energy and carbon dioxide. Photosynthesis occurs in cell organelles called chloroplasts, which contain chlorophyll and carotenoids, molecules that absorb light energy and change it into a usable form. Heterotrophs, on the other hand, are organisms that cannot make their own food and must eat other organisms to survive. Many heterotrophs eat plants. Other heterotrophs eat animals that have eaten plants. Plants are primary producers in many ecosystems, giving them a vital role in the survival of many other organisms. In addition, oxygen is a byproduct of photosynthesis, and many organisms depend on oxygen to survive. We couldn’t live without plants.
Plants are multicellular organisms with eukaryotic cells. A eukaryotic cell is a relatively large cell with a true nucleus and other organelles that perform specific functions. Plants, protists, fungi, and animals all have eukaryotic cells. Plant cells are distinguished by their cell walls containing cellulose, chloroplasts that perform photosynthesis, and a large central vacuole that holds water and keeps the

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Retrieved Text: A cell or nucleus that may participate in sexual fusion to form a *zygote. It is normally haploid and thus on fusion of two gametes a diploid zygote is formed. In virtually all plants (exceptions are those with a *diplontic life cycle ) meiosis is separated from *gametogenesis by the development of a somatic gametophyte generation (see alternation of generations ). In the primitive algae and fungi the gametes are often naked and *isogamous. In more advanced forms there is a trend through *anisogamy to *oogamy and specialization of the gametes, so that they become better protected and less dependent on water for survival and dispersal. See also sexual reproduction.

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Retrieved Text: Algaes are difficult to define. Some classify the group as all eukaryotic photosynthesizing microorganisms. This definition includes the Euglenoid and Dinoflagellates groups, both of which are known to be more closely related to other groups of non-photosynthesizing protozoa than to other algae. For this reason, those two groups are sometimes classified as protozoa rather than algae. In this discussion, we will group euglenoids and dinoflagellates with the algae so that we may compare their photosynthetic characteristics. Keep in mind that this inclusion does not imply close relation to other algae.
Another difficulty in classifying algae is determining whether they are protists, plants, or whether they merit their own kingdom. Different classification systems answer this question in different ways, with some even splitting the group between the kingdoms Protista and Plantae. Here we have grouped algae with protozoa and slime molds in Protista because mthe majority of algae are unicellular, and even the multicellular algae are structurally simple compared to true plants.
Within the classification of algae, individual species are divided into five groups, based on characteristics such as type of chlorophyll molecule used in photosynthesis and type of reproductive cycle. The structure of the chloroplast is also used, for a very important reason. According to the endosymbiotic theory of chloroplast evolution, proposed by Lynn Margulis of the University of Massachusetts, Amherst, chloroplasts may have evolved when small photosynthesizing cells were engulfed, but not digested, by larger cells. Instead, the two types of cells developed a symbiotic relationship, with the photoautotroph living inside the larger cell. The number of

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Retrieved Text: This biphasic life cycle that plants demonstrate is referred to as an?
The life cycle of a plant from?
The leafy green gametophyte is the haploid generation that produces sperm and eggs. The sperm must swim through a film of water to the egg. The zygote develops into a stalked, diploid sporophyte that emerges from the gametophyte plant. The sporophyte is topped by a brown capsule in which haploid spores are produced by meiosis. These are dispersed and germinate, producing another green gametophyte generation.
What is the function and structure of the flower?
Flowers are the part of the sporophyte generation in flowering plants that is dedicated to sexual reproduction.
Insect and vertebrate pollination is ____ efficient than wind pollination.
that put more efforts into mechanisms to attract the animals (i.e. nectar, odoriferous compounds, appearance and etc.) ensured the success of those flowering plant lineages.
Stamens and carpels are composed of two to three distinctly different parts.
1.) To recap pollination is when a pollen grain lands on the stigma of a flower's carpel.
2.) The pollen generates a tube to transfer the sperm from the male gametophyte to the female gametophyte.
3.) In flowering plants we see a double fertilization from the fusion of the sperm to specific cells of female gametophyte.
4.) This double fertilization gives rise to a zygote and endosperm.
5.) When the female gametophyte develops in the manner previously illustrated (polygonum type), which is the most common, the double fertilization gives rise to a (2n) zygote and a (3n) endosperm.
How do seeds germinate and grow?
Seeds need moisture and warmth to germinate. If conditions

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Retrieved Text: Gametes are specialised haploid cells that are used to combine and when they do they combine to form a new diploid cell. That process of combination is called fertilization.
Now, you are hopefully familiar with sperm and egg, the two most common kinds of gametes that you've heard of. Where sperm they're small specialized for quick delivery of the DNA to the other cell, the other kind of gamete which is called the egg. Eggs are large. Why are they so large? It allows them to accumulate or store up large amounts of resources to provide for their newly developed diploid cell which will eventually become some new offspring like you and I became came from a single fertalized egg.
We take a look over here we can see in this scale, this thing that looks almost like a planet, that's the egg and you can see how much larger the egg is in size comparison to the sperm. Now if they were both the same size, they would be called isogametes.
We take a look at an isogamete. Every isogamete looks like the other. Now how are iso- how are sperm and egg made different? That happens during the process of either spermatogenesis or oogenesis.
Here we see a generic description of meiosis. The process of making gametes where here we have a cell that has let's suppose four chromosomes. Ultimately it can create four haploid cells. So this is a diploid cell. See it has pairs of homologous chromosomes. These are individual haploid cells, no more do they

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Retrieved Text: Why don’t cyanobacteria and bacteria reproduce by mitosis?
Damaged cells of an organism are usually ___ by mitosis.
All the chromosomes in a diploid cell are paired.
How many chromosomes are produced by the first division during meiosis?
Which statement(s) correspond(s) correctly to a mutation?
The kind of cell division associated with an increase in size and weight of an organism is called ___.
Gametes have ___ the chromosome number of the parent cell.
Chromosomes are attached to the ___ during the metaphase of mitosis.
The spindle apparatus disintegrates during the ___ of mitosis.
-Plant cells divide by means of a cell plate.
How does mitosis in animal cells differ from mitosis in higher plant cells?
Occasionally asexual reproduction can cause undesirable proliferation of an organism.
Nearly all plants can be reproduced asexually.
The new plant produced by the technique of layering must remain attached to the stem of the original plant.
A successful scion will produce the product of the rootstock with greater quality.
The technique of asexual reproduction most commonly used in the production of fruit trees is ___.
The vigor of a rootstock is usually ___ than that of the root system produced by the scion.
Asexual reproduction is most common in plants growing in ___ climates.
An elongated, horizontal stem that grows at the surface of the ground or just below it is called a rhizome.
Animals have more mechanisms for asexual reproduction than plants.
The stock is inserted into the scion during grafting.
The most commonly used method of asexual reproduction used in gardening is the cutting.
Root cuttings are more commonly used than stem cuttings.
A ___ is a plant structure with enlarged

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Retrieved Text: die „Reduktionsteilung“ beginnt im Diplonten mit einer eigenartigen Zelle [...], deren Nachkommen, die „Haploten“ [...] auf die ursprüngliche Chromosomenzahl herabgesetzt sind, und wiederum ein einfaches Lebewesen, den „Haplonten“ [...] durch neue Zellenteilungen erzeugen.
From this organism [the haplont] arise the gametes by ordinary mitosis; and by their union is produced the zygote from which arises a diploid, asexual spore-producing diplont (in plants the sporophyte), thus completing the life-cycle.
1: The diploid stage of a life cycle; diplophase, 2: An organism having a life cycle in which the direct products of meiosis act as gametes; only the gametes of diplonts are haploid; cf. haplont.

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Retrieved Text: Distinguish, differentiate, compare and explain what is the main difference between Gametogenesis from Embryogenesis. Comparison and Differences.
1. Gametogenesis is the formation of male and female gametes. Embryogenesis is the formation of an embryo from the zygote.
2. In Gametogenesis, gametes are the haploid cells. In Embryogenesis, an embryo is a diploid cell.
3. Both mitotic & meiotic cell division take place in Gametogenesis. Only mitotic division occur in Embryogenesis.

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Retrieved Text: Human development begins at fertilization when a sperm fuses with an oocyte to form a single cell, the zygote. This highly specialized, totipotent cell marks the beginning of each of us as a unique individual... The zygote divides many times and becomes progressively transformed into a multi-cellular human being.
Last week I watched CNN reporter Chris Cuomo and Marco Rubio have this discussion over the matter of abortion and the meaning of "human life."
RUBIO: No, science has decided when it is human life.
CUOMO: Science has not decided it’s at conception.
RUBIO: No, let me correct you. Science has—absolutely it has.
At this point Cuomo made me want to jump through the flat screen of my TV and slap some scientific sense into him!
The conceptus (fertilized egg) is alive. It is a living thing.
It is not a daisy life or a fish life or a mosquito life or a rhinocerous life. It is a human conceptus, AKA human life.
Just as frog life begins in the frog egg, so does human life begin in the fertilized egg in a mother's womb.
Cuomo accused Rubio of "oversimplifying," and that he was answering the question based on his faith, not science."
Cuomo: "We'll have scientists on the show all morning who will say we cannot say it is definitely human life at conception. It's more faith than science."
Rubio: "They can't say it's human life? What would it become then? A cat? I can tell you that every single one of us started at that same stage, that it can't become anything other than a human

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Retrieved Text: Mitosis is the process of cell division that enables organisms to maintain cell populations and grow. All chromosomes duplicate themselves prior to cell division, followed by partitioning of these exact copies into daughter cells. In the image to the right, two sets of chromosomes are going through mitosis.
In contrast, meiosis is a two-part cell division process which results in reproductive cells (eggs and sperm) with one-half the number of chromosomes of the parent cell.
In males, the process results in four equal gametes with one chromosome each (sperm cells—not shown). In females, each ovum is produced by two chromosome divisions, called the first and second meitic divisions, and the parent cell's cytoplasm and organelles end up in one gamete.
When a haploid sperm cell fertilizes a haploid ovum, a diploid zygote is formed, with one set of chromosomes donated from each parent.

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Retrieved Text: Life is made up of many special events, one of them is fertilization. It ‘a phenomenon of sexual reproduction, in which two gametes from different species bind to bring the formation of a new cell, which later take the name of the zygote.
There are several cases of fertilization: there is the inner one, in which the male gametes are released directly into the female apparatus, and the external one which is that fertilization which mostly takes place in water, in which the individual releases the gametes so that the another individual may collect them in opportune moments. Finally there is the assisted reproduction in which the union of gametes occur via artificial. But what are the stages of fertilization? Firstly million sperm reach the fallopian Faloppio, which are later attracted the oocyte, but only one of them manages to penetrate the egg, and then finally to fertilize the zygote. As a result of this process is followed by others, such as the development of the embryo, placenta and fetus.
The placenta begins to develop at conception.
It is therefore a vital organ to the fetus, with which it is in close relation. The main task of the placenta to the fetus is to ensure the necessary nutrients for proper development.
The fetus is nothing but the product of “mutations” that the embryo undergoes from the third month. Life is made up of many events, processes unknown to us, we begin to know them without dwelling on what’s appearance.
Previous articleWHAT TIME IS IT?

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Retrieved Text: Spirogyra is one of the commonest and large genus with about 300 species growing as free-floating masses in stagnant or slowly moving waters (streams). Some species, e. g., Spirogyra adnata are attached to the substratum through a basal rhizoidal cell. The masses of plants are slimy to touch because the filaments are surrounded by pectic sheaths which when come in contact water forms mucilage, therefore it is known as water-silk or pond-scum. The spirogyra grows abundantly in spring.
Spirogyra is unbranched with cylindrical cells connected end to end in long green Filaments. The individual cell is cylindrical, much longer than broad. In free-floating species, there is no distinction between the basal and distal ends, whereas in attached forms the lowermost cell develops a rhizoidal outgrowth called holdfast which helps in attachment.
Each has a well-developed cell wall. The cell wall has two layers the outer wall is composed of cellulose while the inner wall is of pectin.
The cytoplasm forms a thin lining between the cell wall and the large vacuole. Electron microscope studies show that mitochondria, endoplasmic reticulum, dictyosomes and other cytoplasmic inclusions are also present in the cell. The chromosomes vary from species to species from 5-24.
Each cell has a prominent nucleus in the center, suspended by the thin strands of cytoplasm from the inner part of the cell wall.
Chloroplasts are embedded in the peripheral Cytoplasm and their numbers are variable (as few as one). The chloroplasts are ribbon shaped and spirally resulting in the prominent and characteristic green spiral on each filament chloroplast contains several pyrenoids,

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Retrieved Text: In humans is it possible to fertilize a ovum with another ovum from the same female subject?
I already found some works in which the ovum is fertilized by a somatic cell (see e.g. this ), but I am looking for fertilization specifically by another ovum.
Around a year ago I found in the internet a Japanese (ongoing) study on this, but cannot locate it any more.
Consider that somatic cells are properly diploid. Whereas an ovum itself just contains a haploid number of chromosomes. In typical sexual reproduction the sperm fertilizes the ovum which would than bring the chromosome number to to correct tally. So combining the genetic material in two ovum should bring the chromosome count to the correct tally as well, but scientists would need to somehow motivate the activities that happen when typical sexual reproduction occurs. It's likely very challenging to do that if not highly improbable. Should it work, this process could only produce female children.
Not the answer you're looking for? Browse other questions tagged molecular-genetics reproduction human-genetics cytogenetics or ask your own question.
The probability of indirect human fertilization?
Why does the ovum prefers to be arrested at metaphase 2 of meosis before fertilization? What is the possible advantage of this process?
Why are so many spermatozoa produced when only one of them fertilises the ovum?
What is the need for lobules in (human) testicles?

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Retrieved Text: This set contains 67 questions on plant reproduction, anatomy and physiology as well as plant evolution.
A) formation of motile male gametes.
B) alternation of sporophyte and gametophyte generations.
C) presence of both haploid and diploid stages.
Which of the following is NOT a characteristic of plants?
A) Glucose is made from photosynthesis.
B) Cell walls contain cellulose.
D) Diploid and haploid generations alternate in their life cycle.
E) Diploid and haploid phases of their life cycle produce spores.
Cactus plants are adapted to the hot and dry deserts of North and South America. Which of the following characteristics would NOT help cacti to survive the extreme heat and low rainfall?
A) A thick, waxy cuticle.
B) A stem with a small surface area.
C) Stomata that are closed during the day.
D) Thin leaves with a large surface area.
Transport of the products of photosynthesis is understood to occur by pressure flow through the phloem from a source (such as the leaves where the products are produced) to a sink (such as a developing fruit where they are used or stored). Which of the following statements about this transport is FALSE?
A) Water enters the phloem by osmosis.
B) Phloem tubes in a source have a low water pressure.
C) Water and sugar move through the phloem tubes because of pressure.
D) Sugar is removed from phloem by active transport in the sink area.
E) Solutes are pushed along by the flow of water in the phloem.

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Retrieved Text: Which cartoon shows the correct way for the chromosomes to line up at the metaphase plate during mitosis?
What would happen if one chromosome failed to have microtubules from both poles attach?
One daughter cell would not have a copy of that chromosome.
Diatoms are protists that have rigid glass walls. Based on this you can conclude that they carry out cytokinesis similarly to ______________.
What would happen if a cell were unable to properly condense its chromosomes during prophase?
The chromosomal DNA would be subjected to shearing forces, fragmenting the chromosome.
What would happen if cytokinesis occurred before telophase was completed?
A cell that has just exited the G1 phase of the cell cycle (and will eventually go on to divide) will next enter ___________________.
Chromosomes condense and begin to be visible during _____________.
A number of chemical treatments cause microtubules to fall apart. Colchicine (mitonic inhibitor) is one such drug. What would happen if a dividing cell was treated with colchicine?
What would happen to a cell if it went directly from prophase to anaphase (i.e., it failed to undergo metaphase)?
The daughter cells would probably not get equal numbers of chromosomes.
A chimpanzee bone marrow cell, in prophase of mitosis, contains 48 chromosomes. How many chromatids does it contain?
When do homologous chromosomes pair?
Starting with one cell, how many daughter cells will be formed when meiosis is complete?
Sperm cells and ova can be classified as ______________ cells.
How many pairs of homologous chromosomes are found in human males?
The cellular process by which gametes are formed from specialized nonreproductive cells is ________ .
Crossing over occurs during which stage

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Retrieved Text: 1. the process of reproduction.
2. a class composed of all individuals removed by the same number of successive ancestors from a common predecessor, or occupying positions on the same level in a genealogical (pedigree) chart.
alternate generation reproduction by alternate asexual and sexual means in an animal or plant species.
asexual generation (direct generation) production of a new organism not originating from union of gametes.
first filial generation the first-generation offspring of two parents; symbol F1.
parental generation the generation with which a particular genetic study is begun; symbol P1.
second filial generation all of the offspring produced by two individuals of the first filial generation; symbol F2.
sexual generation production of a new organism from the cell formed by the union of a male gamete (spermatozoon) and a female gamete (oocyte).
spontaneous generation the discredited concept of continuous generation of living organisms from nonliving matter.
reproduction by fission, gemmation, or in any other way without union of the male and female cell, or conjugation.
Reproduction by fission, gemmation, or in any other way without union of the male and female cells, or conjugation.
Synonym(s): heterogenesis (2) , nonsexual generation.
2. a class composed of all individuals removed by the same number of successive ancestors from a common predecessor, or occupying positions on the same level in a genealogical (pedigree) chart. Said also of antibiotics or other chemicals derived from parent compounds.
reproduction by alternate asexual and sexual means in an animal or plant species.
production of a new organism not originating from union of gametes. Called also direct generation.
the first generation offspring of two parents; symbol F1.
all of

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Retrieved Text: (Solved) The union of gametes produces a zygote.
The union of gametes produces a zygote.
Solved If gametes were diploid like somatic cells, how many chromosomes would the zygote contain?

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Retrieved Text: Signaling events during male germ cell differentiation: bases and perspectives.
Berruti G. Signaling events during male germ cell differentiation: bases and perspectives. Front Biosci. 1998;3D1097-108.
In all species, reproductive function depends on the ability of the individual to produce functional differentiated gametes. Spermatogenesis is a cyclic process in which diploid spermatogonia differentiate into mature haploid spermatozoa. Thus from a genetic point of view, spermatogenesis can be divided into two phases, namely the diploid and haploid phase. Indeed, this complex differentiation process is still more intriguing since primary spermatocytes, if genetically diploid, are functionally tetraploid, while elongating spermatids, the germ cells undergoing the most dramatic morphological changes, if genetically haploid, become functionally anucleate due to ongoing condensation of chromatin resulting in an inactive nuclear DNA. This multi-step differentiative pathway is dependent on a specific environment provided by the anatomical and cellular relationships that take place in the testis and more specifically within the seminiferous tubules. Already, early anatomists (mind comes to Enrico Sertoli and Gustaf Retzius) were fascinated by the mixed cellular composition of the testis correctly deciphered as a whole of interacting and interdependent cell types despite the fact these belong to two well-established and different cell lineages, i.e, the somatic and germinal line. Since their time (the XIX century) up to-day a conspicuous bulk of experimental work and a relative massive bibliographic documentation have been provided. From this it stands out : a) a sophisticated role played by the cyclic hormonal control elicited by the hypothalamic-pituitary axis; b) the structural membrane specializations of Sertoli-germ cell communications; c)

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Retrieved Text: The process of meiosis creates 4 haploid gamete cells from a diploid cell. In animals these gametes are called eggs and sperm and in plants they are called eggs and pollen. For meiosis to occur it must go through two divisions, Meiosis I and Meiosis II. During Meiosis, the cell goes through the same stages as Mitosis (Interphase, Prophase, Metaphase, Anaphase, and Telophase/Cytokinesis), but it goes through these phases twice, but with some minor differences.
Creates 4 haploid gamete cells from a diploid cell.
At this point the DNA is in its chromatin form and the DNA replicates.
Homologous Chromosomes (matching chromosomes from mom and dad) join up together and exchange share genetic information. Happens during Prophase I of meiosis.
Matching chromosomes from mother and father. They are the same size, shape and carry genes for the same traits.
The chromosomes line up down the middle along with their homologous pair.
The homologous chromosomes pull apart from one another and move toward opposite poles.
Chromosomes are now at separate poles, nuclear membranes start to form around the 2 sets of chromosomes, and the chromosomes start to unwind back into chromatin. Cytokinesis occurs and the two cells split. These two cells are haploid at this point since each cell contains only 1 of each homologous pair. The next 4 phases occur to each of these cells.
Notice that we skip interphase this time around because there is no replication of DNA between Meiosis I and Meiosis II.
At this point the chromosomes reorganize and the nuclear membranes start to dissolve again. Sister chromatids are joined by

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Retrieved Text: Haploid is the term used when a cell has half the usual number of chromosomes. A normal eukaryote organism is composed of diploid cells, one set of chromosomes from each parent. However, after meiosis, the number of chromosomes in gametes is halved. That is the haploid condition.
In humans, the diploid number of chromosomes is 46 (2x23). The number in haploid cells (sperm and eggs) is 23. Some types of animals are haploid, such as male Hymenoptera (ants, bees and wasps). This is a special genetic system called haplodiploidy.
Some plants and animals are polyploid, with more than two sets of chromosomes. For example, one species of wheat is hexaploid, with six sets of chromosomes, although other species of wheat have only two sets. Because so many organisms are diploid, it can become confusing whether haploid refers to one set of chromosomes or more than one. The special term monoploid can be used; it means one set of chromosomes.
Haploid Facts for Kids. Kiddle Encyclopedia.

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Retrieved Text: When one walks through a contemporary forest, all of the surrounding trees are vascular plants. Wood, which is made up primarily of xylem , and bark, which contains phloem , are the major structural elements of the trunks and stems. These trees produce seeds, whether they be formed within the cones of the pines or within fruits, such as the winged samaras of maples or the fleshy cherries of the cherry tree. In the Carboniferous period a similar hike would also place one in a forest of woody trees, many as large as 98 feet (30 meters) tall, but there would be no seeds produced. These plants were seedless vascular plants, which were propogated by spores. Ultimately they became extinct, leaving behind expansive fossil fuel deposits.
The differences between spores and seeds are extensive. Seeds are multicellular structures that provide a protected place where the egg (n) was to be fertilized by male gamete nuclei (n) in pollen. The resulting cell, called a zygote , is diploid (2n), the same as the original plant that produced it. It repeatedly divides mitotically, while still within the protection of the seed coat, to form an embryo. The embryo may remain dormant for a significant time period but ultimately emerges from the seed when it germinates.
The seedless vascular plants do not have this protection. Their gametes are produced mitotically by a gametophyte (n) that lives independently. There are often many vase-shaped archegonia on these small plants, and the unfertilized egg is inside the base of this structure. The embryo formed

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Retrieved Text: Internal fertilization is the process when the syngamy (union of male and female gamete) occurs inside the female body after insemination using copulation. In contrast, External fertilization is the syngamy outside the female body, that is in the outer environment especially in water bodies.
Internal fertilization is followed by mammals, birds, while external fertilization is supported by mostly aquatic animals and few amphibians.
We all are aware of the word fertilization, which defines the union of sperm (male gamete) and egg nucleus (female gamete) to produce diploid cell or zygote, which further develops or grow into the young ones of their generation. Internal and External fertilization are the two types of fertilization, which takes place among various groups of animals, and with this content, we will be discussing the diverse features of them.
Meaning The process of fusion of male and female gamete (sperm and egg) taking place inside the body of the female, is called as internal fertilization. The process of fusion of male and female gamete (sperm and egg) taking place in the external environment (in water bodies) and so-called as external fertilization.
Gametes released Less number of gametes (sperms) are released, which gets deposited inside the female body. Numerous gametes (sperms and egg) are released into the environment. These gametes are of male as well as of female.
Process involves Only male gametes are released or discharged into the female genital tract. Both male and female release or discharge their gametes in their external surrounding.
Further process of development (syngamy) occurs inside the body only. Further process of development

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Retrieved Text: Check new design of our homepage! Reproduction is one of the distinguishing features of living organisms, and is essential for the survival of any species. Such perpetuation of species is achieved through two fundamental Reproduce asexually - sexual and asexual. Sexual reproduction involves the formation of a zygote, through the fusion of gametes from two parents.
The zygote develops into an embryo, and grows into an offspring. On the other hand, asexual reproduction involves Reproduce asexually formation of a genetically identical offspring from a single individual. The primitive life forms predominantly exhibit asexual reproduction. The ability to exist in two genders evolved with the changing environment. With the increase in complexity of the newly evolved life forms, the dominance of asexual reproduction decreased.
Nevertheless, each kingdom encompasses a set of strictly asexual organisms, as well as a set of organisms characterized by the presence of both sexual and asexual phases. What is Asexual Reproduction? Asexual reproduction is a reproductive process devoid of gamete formation and fertilization, and mostly proceeds via mitosis. The resultant offspring is a clone of the parent organism due to Reproduce asexually absence Reproduce asexually genetic exchange.
Budding, fission, fragmentation, vegetative propagation, etc. Such reproductive cycles complete in less time, as compared to sexual reproduction, which serves as an evolutionary advantage. However, owing to the lack of genetic variation, the ability to adapt to changing environment is limited.
In asexual organisms, genetic Reproduce asexually can Reproduce asexually only through random mutations. Being so, they are dependent on favorable mutations to cope with environmental changes. List of Organisms

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Retrieved Text: Rescan, Lenormand and Roze (2016) recently published new models on the evolution of life cycles in The American Naturalist.
Most animals and protists have diploid life cycles in which the haploid stage is reduced to a single-celled gamete.
Other organisms, such as charophytes and dinoflagellates, have a haploid life cycle in which the diploid phase is reduced to the zygote and meiosis occurs before any mitotic development.
There’s a third type of life cycle, that regular TME readers may have stumbled across with my posts: haploid-diploidy in which somatic development occurs in both haploid and diploid stages. In seed plants, the haploid stage is rather limited, but in fungi, mosses and macroalgae, the haploid stage is much more important.
[Due to the difference in duration of one phase and the corresponding limits to selection], the problem of the evolution of life cycles (i.e., the relative degrees of development of the haploid and diploid phases) is often recast in terms of the opportunity of selection within each phase.
One model suggests diploids may benefit from the masking of deleterious mutations. But, this assumes deleterious mutations have the same effect in both haploids and homozygous diploids. Recent transcriptomic studies in haploid-diploid species, such as Coelho et al. (2007), have demonstrated some genes are only expressed in one policy and mutations in these genes would have no effect in the other stage as they are not expressed.
Moreover, these genetic models cannot explain the evolutionary stability of haploid-diploid life cycles without considering additional mechanisms, such as ecological niche differentiation (Hughes and Otto 1999).
the interplay between

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Retrieved Text: Bryophytes are the group of plants that are the closest extant relative of early terrestrial plants. The first bryophytes (liverworts) most likely appeared in the Ordovician period, about 450 million years ago. Because of the lack of lignin and other resistant structures, the likelihood of bryophytes forming fossils is rather small. Some spores protected by sporopollenin have survived and are attributed to early bryophytes. By the Silurian period, however, vascular plants had spread through the continents. This compelling fact is used as evidence that non-vascular plants must have preceded the Silurian period.
More than 25,000 species of bryophytes thrive in mostly damp habitats, although some live in deserts. They constitute the major flora of inhospitable environments like the tundra, where their small size and tolerance to desiccation offer distinct advantages. They generally lack lignin and do not have actual tracheids (xylem cells specialized for water conduction). Rather, water and nutrients circulate inside specialized conducting cells. Although the term non-tracheophyte is more accurate, bryophytes are commonly called nonvascular plants.
In a bryophyte, all the conspicuous vegetative organs—including the photosynthetic leaf-like structures, the thallus, stem, and the rhizoid that anchors the plant to its substrate—belong to the haploid organism or gametophyte. The sporophyte is barely noticeable. The gametes formed by bryophytes swim with a flagellum, as do gametes in a few of the tracheophytes. The sporangium—the multicellular sexual reproductive structure—is present in bryophytes and absent in the majority of algae. The bryophyte embryo also remains attached to the parent plant, which protects and nourishes it. This is a characteristic of

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Retrieved Text: Like all plants Toxicodendron diversilobum exhibits an alternation of generations. This means that during the life cycle of the plant it alternates between a multicellular diploid sporophyte generation and a multicellular haploid gametophyte generation. Since the Pacific poison oak is in the phylum Angiosperm it has a dominant sporophyte generation which means that the gametophyte generation will be more dependent on the sporophyte generation.
The first part of the angiosperm life cycle takes place in the flower of the plant. Here in the anther the microsporocytes develop and undergo meiosis which produces haploid microspores. Each microspore undergoes one division of mitosis to form a generative cell and a tube cell. Together they form an immature pollen grain. The generative cells then go through a second mitotic division which produces two sperm nuclei. Inside the ovule one megaspore undergoes meiosis to form four haploid megaspore. Three die off and one remains. The remaining megaspore undergoes three mitotic divisions and generates an 8 nucleate embryo sac also known as a megagametophyte.
Next pollination occurs. The pollen grain germinates on the stigma where a pollen tube grows down into the style. Eventually it grows down into the ovary through the micropyle. One sperm nucleus then fuses with the egg which creates a diploid zygote, and the other sperm fuses with the central cell of the egg to form the endospore.
Now that the embryo has formed it grows inside the embryo sac. The ovule creates a protective seed coat around the embryo and embryo sac. Then the seed is dropped from fruit

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Input Text: Answer the following question given this paragraph: 

An aldehyde is a carbonyl in which the carbon atom is bonded to one carbon atom and one hydrogen atom (or two hydrogen atoms, see below). Because the hydrogen atom is so small, the partial positive charge on the carbonyl carbon is very easy for other molecules to approach, making aldehydes a particularly reactive type of carbonyl. Aldehydes are versatile reactants for a wide variety of organic syntheses. Many aldehydes also have distinctive flavors and aromas. For example, the flavor of cinnamon is primarily due to the molecule cinnamaldehyde, and vanillin is the aldehyde most responsible for the smell and taste of vanilla extract.


Q: Name a carbonyl in which the carbon atom is bonded to one carbon atom and one hydrogen atom (or two hydrogen atoms).

 Choices:

- ester

- acetylcholine

- ketone

- ester

A:

Target Text: aldehyde

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Retrieved Text: When carboxylic acids containing a carbonyl group two bonds away (on the β carbon) are heated, carbon dioxide is lost.
β-Keto (or 3-keto) acids have another carbonyl group in the β position (or on the third carbon atom), from where their names are derived. Other carboxylic acids which do not have a carbonyl function in this place do not decarboxylate, regardless of the presence of carbonyl groups elsewhere in the molecule. β-Keto acids are very unstable and readily undergo the elimination of carbon dioxide or simply decarboxylation under mild conditions. Ketones are obtained in this reactions.
Decarboxylation occurs readily whenever a carboxyl group is bonded to the α carbon of another carbonyl group for two reasons. First, the oxygen of the β-keto function is ideally positioned to bond with the carboxy hydrogen forming a cyclic six-atom transition state. And this transition state has aromatic character because three electron pairs shift around the cyclic six-atom array which is a second good reason. Thus enol is formed which tautomerizes rapidly to the final ketone product.

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Retrieved Text: The first four carboxylic acids mix with water in all proportions. This high solubility of water can be explained by hydrogen bonding (the same reason as for alcohols).
Hydrogen bonding is caused by the ability of particular atoms to strongly attract the electrons in a bond. A measure of how strongly an atom in a compound attracts electrons in a bond is called electronegativity. Hydrogen bonds are formed when a hydrogen atom is covalently bonded to one of the electronegative atoms, fluorine, chlorine, oxygen or nitrogen.
Carboxylic acids contain the carboxyl group (COOH or CO2H). The carboxyl group is made up of a carbonyl group (C=O) and a hydroxyl group (O—H). Like alcohols, in carboxylic acids the hydrogen bonds are formed due to the covalent bonds between one oxygen atom and one hydrogen atom in the hydroxyl group (O—H). Oxygen is a highly electronegative atom and attracts the electrons in the O—H bonds towards itself. Since the proton in the nucleus of the hydrogen atom is only slightly screened the action of the oxygen pulling the electrons away from the hydrogen results in a net positive charge on the hydrogen atom. Consequently there is also a net negative charge on the oxygen atom resulting in an imbalance of charge across the hydroxyl group. The overall hydroxyl group is said to be polar because like a magnet it has two opposite charges on either ends (its poles). The net positive hydrogen atom is readily available to attract the negative electron clouds from the oxygen atom in an adjacent carbonyl

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Retrieved Text: What Is Oxidation of a Tertiary Alcohol?
Tertiary alcohols do not undergo oxidation in the presence of an oxidizing agent. This is because the carbon atom that contains the alcohol functional group is devoid of any hydrogen atoms, which are necessary in the oxidation mechanism of alcohols.
There are three types of alcohols, which are classified based on the number of hydrogen atoms bonded to the carbon atom that is bonded to the oxygen atom in the functional group of an alcohol. Primary alcohols have two hydrogen atoms, secondary alcohols have one hydrogen atom and tertiary alcohols have no hydrogen atoms bonded to the carbon that is bonded to the oxygen atom.
Oxidation of alcohols can only take place in the presence of an oxidizing agent, such as acidified potassium dichromate, which in turn is reduced during the process. The dichromate (IV) ions are reduced to chromium (III) ions through the addition of electrons. This process involves the removal of the hydrogen atoms bonded to the oxygen itself in the alcohol?s functional group, as well as from the carbon containing the alcohol group (known as the carbinol carbon).
Since primary alcohols contain two hydrogen atoms on the carbinol carbon, they can be oxidized to aldehydes and then to carboxylic acids. Secondary alcohols can be oxidized only once to ketones, since they contain only one hydrogen atom on the carbinol carbon. Tertiary alcohols are resistant to oxidation, since their carbinol carbons have no hydrogen atoms that can take part in the transfer of electrons to the dichromate ions.
What Is the Hottest

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Retrieved Text: · Instead of gaining and loosing electrons, carbon shares its 4-electrons with another element or carbon to form molecule.
· Covalent bonds are formed as a result of sharing of electrons. Example- H2, O2, N2. Covalent compounds have low melting point and boiling point due to small intermolecular forces.
· H2forms by sharing valence electrons (1 per atom of H) and produce single bond between two hydrogen atoms.
· O2 forms by sharing valence electrons (2 per atom of O) and produce double bond between two oxygen atoms.
· N2forms by sharing valence electrons (3 per atom of N) and produce triple bond between two nitrogen atoms.
· Methane, CH4is simple carbon compounds and used as a fuel on large scale and also a major component of CNG (Compressed Natural Gas). Methane formed due to sharing of 4 valence electrons of carbon with 4 hydrogen atoms.
Carbon have three allotropes i.e. Diamond, Graphite and fullerene.
Diamond formed due to rigid three dimensional structures of carbon atoms because each carbon atom bonded to another 4 carbon atoms. It is hardest substance.
Graphite formed due to presence of hexagonal array layers above one another, and layers of hexagonal arrays formed because each carbon atom bonded to another 3 carbon atoms with 2 single and 1 double bond. It is smooth, slippery and very good conductor of electricity.
Fullerenes (C-60) are also an allotrope of carbon in which carbon atoms are arranged in football like shape.
Carbon shows versatile nature because it has two characteristics features which are catenation and tetravalency. These both feature gives large numbers of compounds.
Catenation

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Retrieved Text: show the direction of electron flow in a reaction mechanism.
never show the movement of atoms. Atoms are assumed to follow the flow of the electrons.
The reaction of hydrogen chloride with water provides a simple example of how to use curved arrow notation. Here we invoke the first of many “A Mechanism for the Reaction” boxes, in which we show every key step in a mechanism using color-coded formulas accompanied by explanatory captions.
The curved arrow begins with a covalent bond or unshared electron pair (a site of higher electron density) and points toward a site of electron deficiency. We see here that as the water molecule collides with a hydrogen chloride molecule, it uses one of its unshared electron pairs (shown in blue) to form a bond to the proton of HCl. This bond forms because the negatively charged electrons of the oxygen atom are attracted to the positively charged proton. As the bond between the oxygen and the proton forms, the hydrogen–chlorine bond of HCl breaks, and the chlorine of HCl departs with the electron pair that formerly bonded it to the proton. (If this did not happen, the proton would end up forming two covalent bonds, which, of course, a proton cannot do.) We, therefore, use a curved arrow to show the bond cleavage as well. By pointing from the bond to the chlorine, the arrow indicates that the bond breaks and the electron pair leaves with the chloride ion.
Add curved arrows to the following reactions to indicate the flow of electrons for all of

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Retrieved Text: What is the Difference Between Cis and Trans Fats?
The goal of this lesson will be to learn how to identify an asymmetric carbon by discussing their definition and carefully studying some specific examples of compounds that contain asymmetric carbons.
When you hear the word symmetry, what's the first thing that comes to mind? The idea of symmetry is that if we cut the object of interest in half, we end up with two equal halves. Did you know that the human body has an element of symmetry to it? If you were to imagine cutting yourself in half length-wise, you would end up with two equal halves of yourself. Another way of stating this would be that your body contains a mirror plane running longitudinally.
Did you know that sometimes organic molecules can have elements of symmetry, too? A molecule is symmetrical if you can divide it in half some way and end up with two halves that are the same. In this lesson, we're actually going to be focusing on the opposite of symmetry, a concept called asymmetry. Specifically, we're going to be learning about what's called an asymmetric carbon atom within an organic compound.
An asymmetric carbon atom is defined as a carbon within an organic compound that contains four different atoms or groups of atoms (substituents) bonded to it. As an example, consider a carbon atom that's bonded to an -OH group, a hydrogen, a fluorine, and a bromine. Notice how the carbon is bonded to four different substituents, making it an asymmetric carbon.
So how we

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Retrieved Text: Migratory insertion is a term to describe the transfer of a ligand from a metal to a carbon monoxide that is also bound to the metal. It is a special case of a 1,1-insertion. In a 1,1-insertion, a group is transferred from a metal to an atom attached to the same metal. A general 1,1-insertion is shown in figure MI2.1.
Figure MI2.1. A general 1,1-insertion. Formal charges would vary according to the specific groups X, Y and Z.
At the end of the 1,1-insertion, the ligand Z has attached to the 1st atom in the next ligand attached to the metal.
Carbonyl groups in organic compounds are electrophilic. The polar carbon-oxygen double bond places positive charge on the carbon, so the carbon atom attracts nucleophiles. One of the nucleophiles that can react with a carbonyl is a complex hydride, such as a borohydride ion or an aluminum hydride ion. Sometimes, these complex hydrides are anionic, making them more nucleophilic. An example is sodium borohydride, NaBH4. Sometimes, the hydride compound is neutral, as in BH3. However, the hydride is still nucleophilic even if the compound is not negatively charged, because of the electronegativity difference between the hydrogen and the boron (or the aluminum). A hydride ion is donated as a nucleophile to the electrophilic carbonyl. Transition metal hydrides, like boron and aluminum hydrides, are frequently nucleophilic. They can donate hydrides to electrophiles.
A hydrogen attached to a metal atom frequently acts like a hydride.
A nucleophilic hydride can donate to a carbonyl carbon.
Figure MI2.2. CO binding to a metal ion.
"Inorganic carbonyls", or

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Retrieved Text: Electron dot structures, also called Lewis structures, are a graphical representation of the way electrons are distributed throughout a compound. Each element's chemical symbol is surrounded by lines, representing bonds, and dots, representing non-bonded electrons. When drawing an electron structure, your goal is to make each element's valence, or outer electron shell, as full as possible, without going over the maximum number of electrons for that shell.
Determine each element in the structure by looking at its chemical formula. For example, carbon dioxide's formula is CO2. Therefore it has one carbon atom and two oxygen atoms.
Look up each element on the Periodic Table. Note each group, or column number. This reflects how many valence electrons the element has. For instance, carbon is in group 4A and oxygen is in group 6A; therefore carbon has four valence electrons and oxygen has six.
Add the valence electrons of all the elements. This is the total number of electrons available for the dot structure. Since 4 + 6 + 6 = 16, there will be 16 electrons in carbon dioxide's Lewis structure.
Determine which element is the least electronegative, or has the weakest pull on the electrons, by looking on an electronegativity chart or by examining the element's position relative to the other elements on the Periodic Table. Elements generally increase in electronegativity from left to right and from bottom to top. Carbon is the least electronegative element in the compound, with a value of 2.5.
Place the least electronegative element in the center of the structure, then surround it with the other

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Retrieved Text: each m independently is an integer from 1 to 3; and each n independently is an integer from 0 to 3.
3. The compound according to claim 1, where R2 and R4are the same.
4. The compound according to claim 1, where each R35independently selected from the group consisting of hydrogen, -NRcRc, -(CH2)m-NRcRc, -C(O)ORd, -(CH2)m-C(O)ORdand -(CH2)m-ORd.
5. The compound according to claim 1, where R2represents phenyl, optionally substituted one, two or three R8groups.
6. The compound according to claim 1, where R2represents phenyl, optionally substituted with one or two R8groups.
7. The compound according to claims 1, 2 or 3, where R2represents tizamidine phenyl.
8. The compound according to claim 1, where R2represents phenyl, substituted with one R8group selected from the group consisting of (C1-C6)alkyl, -ORd, -O-(CH2)m-NRcRc, -O-C(O)ORa, -O-(CH2)m-C(O)ORa, -O-C(NH)NRcRc, -O-(CH2)m-C(NH)NRcRc, -NH-(CH2)m-NRcRcand-NH-C(O)NRcRc.
9. The compound according to claim 1, where R2represents phenyl, substituted with two R8substituents selected from the group consisting of (C1-C6)alkyl, -ORd, -O-(CH2)m-NRcRc, -O-C(O)ORa, -O-(CH2)m-C(O)ORa, -O-C(NH)NRcRc, -O-(CH2)m-C(NH)NRcRc, -NH-(CH2)m-NRcRcand-NH-C(O)NR Rc.
10. The compound according to claim 1, where R2represents phenyl, substituted three R8substituents selected from the group consisting of (C1-C6)alkyl, -ORd, -O-(CH2)m-NRcRc, -O-C(O)ORa, -O-(CH2)m-C(O)ORa, -O-C(NH)NRcRc, -O-(CH2)m-C(NH)NRcRc, -NH-(CH2)m-NRcRcand-NH-C(O)NRcRc.
11. The compound according to claim 1, where R is substituted at the 3-, 4 - and 5-positions.
12. The compound according to claim 1, where R4represents phenyl, optionally substituted one, two or three R8groups.
13. The connection section 12, where R4represents phenyl, substituted at the 3-position, 4-position, 5-position, or combinations thereof.
14. The connection indicated in paragraph 13, where R4represents phenyl, substituted with one R8Deputy selected from the group consisting of (C1-C6)alkyl, -ORd, -O-(CH2)m-NRcRc, -O-C(O)ORa, -O-(CH2)m-C(O)ORa, -O-C(NH)NRcRc, -O-(CH2)m-C(NH)NRcRc, -NH-(CH2)m-NRcRcand-NH-C(O)NRcRc.
15.

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Retrieved Text: The largest database1 of organic compounds lists about 10 million substances, which include compounds originating from living organisms and those synthesized by chemists. The number of potential organic compounds has been estimated2 at 1060—an astronomically high number. The existence of so many organic molecules is a consequence of the ability of carbon atoms to form up to four strong bonds to other carbon atoms, resulting in chains and rings of many different sizes, shapes, and complexities.
The simplest organic compounds contain only the elements carbon and hydrogen, and are called hydrocarbons. Even though they are composed of only two types of atoms, there is a wide variety of hydrocarbons because they may consist of varying lengths of chains, branched chains, and rings of carbon atoms, or combinations of these structures. In addition, hydrocarbons may differ in the types of carbon-carbon bonds present in their molecules. Many hydrocarbons are found in plants, animals, and their fossils; other hydrocarbons have been prepared in the laboratory. We use hydrocarbons every day, mainly as fuels, such as natural gas, acetylene, propane, butane, and the principal components of gasoline, diesel fuel, and heating oil. The familiar plastics polyethylene, polypropylene, and polystyrene are also hydrocarbons. We can distinguish several types of hydrocarbons by differences in the bonding between carbon atoms. This leads to differences in geometries and in the hybridization of the carbon orbitals.
Alkanes, or saturated hydrocarbons, contain only single covalent bonds between carbon atoms. Each of the carbon atoms in an alkane has sp3 hybrid orbitals and is bonded to four other

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Retrieved Text: Aldehydes and ketones are the reactive organic compounds which characteristically undergo nucleophilic addition or condensation reactions. This is because of the difference in electronegative between carbon and oxygen atom. The carbonyl carbon atom is the nucleophilic site as it is electron deficient due to the difference in electronegativity between carbon and oxygen.
The susceptibility of carbonyl carbon to nucleophilic attack is decreased by its attachment to the electron liberating alkyl or aryl groups that reduces the degree of positive charge on the carbon. As well, the increase in steric hindrance regarding the carbon through the bulky hydrocarbon groups obstructs the approach of the attacking nucleophile and contributes to the reduction in this reactivity. Therefore, aldehydes are more reactive than ketones as they have only one hydrocarbon group. The carbonyl carbon in the aldehydes is more positive and less sterically hindered than that in ketones, therefore more susceptible to the nucleophilic attack.
Alkyl groups donate electrons through inductive effects whereas aryl (Ar) groups do so through the resonance.
A Grignard reagent consists of a formula RMgX, here 'X' is a halogen and 'R' is an alkyl or aryl group. For illustration: CH3CH2MgBr.
In the preparation of tertiary alcohols, aqueous ammonium chloride is employed for the hydrolysis as dilute acid brings about dehydration of the alcohol to yield the alkene that is a removal product.
The Aldehydes and ketones undergo addition by hydrogen cyanide to outcome a class of compounds known as 2-hydroxyalkanonitriles (that is, cyanohydrins).
Aldehydes and ketones react reversibly by means of surplus 40 percent hydrogensuphite in excess at room temperature to

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Retrieved Text: Thinking in terms of overlapping atomic orbitals is one way for us to explain how chemical bonds form in diatomic molecules. However, to understand how molecules with more than two atoms form stable bonds, we require a more detailed model. As an example, let us consider the water molecule, in which we have one oxygen atom bonding to two hydrogen atoms. Oxygen has the electron configuration 1s22s22p4, with two unpaired electrons (one in each of the two 2p orbitals). Valence bond theory would predict that the two O–H bonds form from the overlap of these two 2p orbitals with the 1s orbitals of the hydrogen atoms. If this were the case, the bond angle would be 90°, as shown in [link], because p orbitals are perpendicular to each other. Experimental evidence shows that the bond angle is 104.5°, not 90°. The prediction of the valence bond theory model does not match the real-world observations of a water molecule; a different model is needed.
Quantum-mechanical calculations suggest why the observed bond angles in H2O differ from those predicted by the overlap of the 1s orbital of the hydrogen atoms with the 2p orbitals of the oxygen atom. The mathematical expression known as the wave function, ψ, contains information about each orbital and the wavelike properties of electrons in an isolated atom. When atoms are bound together in a molecule, the wave functions combine to produce new mathematical descriptions that have different shapes. This process of combining the wave functions for atomic orbitals is called hybridization and is mathematically

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Retrieved Text: After completing this section, you should be able to write a general mechanism for an alpha‑substitution reaction of a carbonyl compound.
An “alpha‑substitution reaction” of a carbonyl compound is a reaction in which one of the hydrogen atoms on the carbon adjacent to the carbonyl group is substituted by some other atom or group. Attack by the electrophile (E+) can occur on the enol or enolate intermediate.

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Retrieved Text: 1. What is the character of the bond in carbon monoxide?
2. Which of the following molecules contains the oxygen atom with the most negative formal charge?
3. Which of the following structure(s) contribute most to NO2’s resonance hybrid?
4. Which of the following correctly ranks the compounds below by ascending boiling point?
5. Both CO32– and ClF3 have three atoms bonded to a central atom. What is the best explanation for why CO32– has trigonal planar electronic geometry, while ClF3 has trigonal bipyramidal electronic geometry?
1. CO32– has multiple resonance structures, while ClF3 does not.
2. CO32– has a charge of −2, while ClF3 has no charge.
3. ClF3 has lone pairs on its central atom, while CO32– has none.
4. CO32– has lone pairs on its central atom, while ClF3 has none.
6. Which of the following has the largest dipole moment?
7. Despite the fact that both C2H2 and HCN contain triple bonds, the lengths of these triple bonds are not equal. Which of the following is the best explanation for this finding?
1. In C2H2, the bond is shorter because it is between atoms of the same element.
2. The two molecules have different resonance structures.
3. Carbon is more electronegative than hydrogen.
4. Nitrogen is more electronegative than carbon.
8. Which of the following is the best explanation of the phenomenon of hydrogen bonding?
1. Hydrogen has a strong affinity for holding onto valence electrons.
2. Hydrogen can only hold two valence electrons.
3. Electronegative atoms disproportionately carry shared electron pairs when bonded to hydrogen.
4. Hydrogen bonds have ionic character.
9. Which of the following best describes the number and

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Retrieved Text: The Cahn-Ingold-Prelog priority rules, CIP system or CIP conventions are a set of rules used in organic chemistry to name the stereoisomers of a molecule. A molecule may contain any number of stereocenters and any number of double bonds, and each gives rise to two possible configurations. The purpose of the CIP system is to assign an R or S descriptor to each stereocenter and an E or Z descriptor to each double bond so that the configuration of the entire molecule can be specified uniquely by including the descriptors in its systematic name.
The Cahn-Ingold-Prelog rules are distinctly different from those of other naming conventions, such as general IUPAC nomenclature, since they are designed for the specific task of naming stereoisomers rather than the general classification and description of compounds.
R/S and E/Z descriptors are assigned by reference to a priority ranking of the groups attached to each stereocenter (or double-bonded atom, henceforth). The procedure for assigning these priorities (also known as the sequence rule) is the heart of the CIP system.
Two groups are compared first by atomic number of the atoms directly attached to the stereocenter; the group having the atom of higher atomic number receives higher priority. If there is a tie, a list is made for each group of the atoms bonded to the one directly attached to the stereocenter, i.e., the atoms at distance 2 from the stereocenter. Each list is arranged in order of decreasing atomic number. Then the lists are compared atom by atom; at the earliest difference, the group containing

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Retrieved Text: Chapter L3 Section 4 Organic Compounds The Four Bonds of a Carbon Atom More than 90% of all compounds belong to a group called organic compounds. Organic compounds are covalent compounds composed of carbon-based molecules. Fuel, rubbing alcohol, sugar, cotton, paper and plastic belong to this group. All organic compounds contain carbon. Each carbon atom has four valence electrons so each carbon atom can make four bonds with four other atoms.
Section 4 Organic Compounds The Four Bonds of a Carbon Atom, continued Carbon Backbones Structural formulas are models that are used to show how atoms in a molecule are connected. Each line represents a pair of electrons that form a covalent bond.
Section 4 Organic Compounds The Four Bonds of a Carbon Atom, continued Many organic compounds are based on the types of carbon backbones shown below. Some compounds have hundreds or thousands of carbon atoms as part of their backbone.
Section 4 Organic Compounds The Four Bonds of a Carbon Atom, continued Organic compounds may also contain hydrogen, oxygen, sulfur, nitrogen, and phosphorus. The next slide shows three models of carbon backbones.
Section 4 Organic Compounds Hydrocarbons and Other Organic Compounds Many organic compounds contain several kinds of atoms, but some contain only two. Organic compounds that contain only carbon and hydrogen are called hydrocarbons. There are three types of hydrocarbons: saturated hydrocarbons, unsaturated hydrocarbons, and aromatic hydrocarbons.
Chapter L3 Section 4 Organic Compounds Hydrocarbons, continued Saturated Hydrocarbons An alkane, or saturated hydrocarbon, is a hydrocarbon in which each carbon atom in the molecule shares a single bond with

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Retrieved Text: A variety of functional groups contain what is known as a carbonyl, which is a carbon atom double bonded to an oxygen atom. This video lesson focuses on ketones, aldehydes, and amides. Duration: 5:47.
This video lesson focuses on carboxylic acids and esters. Included is the synthesis of methyl salicylate, which is the chemical responsible for the smell of wintergreen. Duration: 7:56.

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Retrieved Text: Alkanes (also known as paraffins or saturated hydrocarbons) are chemical compounds that consist only of hydrogen and carbon atoms and are bonded exclusively by single bonds (i.e., they are saturated compounds) without any cycles (or loops; i.e., cyclic structure). With the formula CnH2n+2, Alkanes belong to a homologous series of organic compounds in which the members differ by a constant relative molecular mass of 14. They have two main commercial sources: crude oil and natural gas.
Each carbon atom has 4 bonds (either C-H or C-C bonds), and each hydrogen atom is joined to a carbon atom (H-C bonds). A series of linked carbon atoms is known as the carbon skeleton or carbon backbone. The number of carbon atoms is used to define the size of the alkane (e.g., C2-alkane).
The simplest possible alkane (the parent molecule) is methane, CH4. There is no limit to the number of carbon atoms that can be linked together, the only limitation being that the molecule is acyclic, is saturated, and is a hydrocarbon. Saturated oils and waxes are examples of larger alkanes where the number of carbons in the carbon backbone is greater than 10.
Alkanes are not very reactive and have little biological activity. Alkanes can be viewed as a molecular tree upon which can be hung the more biologically active/reactive portions (functional groups) of the molecule.

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Retrieved Text: Sep 26, 2013 · For the CH4O Lewis structure, calculate the total number of valence electrons for the CH4O molecule (CH4O has 14 valence electrons).
The molecular geometry of C 2 H 2 Br 2 is trigonal planar. The molecular geometry of C 2 H 2 Br 2 is trigonal planar.
Apr 09, 2016 · the only nonexotic neutral compound with that formula is methanol, usually written CH3-OH. the carbon is at the center with the three H’s forming a pyramidal structure below it at 3 of the vertices of an imaginary tetrahedron, and the O at the 4th vertex. the H then juts out at a ~109.5 degree angle away from the O. the O-C bond, O-H bond, and the 2.
Apr 08, 2008 · This Site Might Help You. RE: Can you help me with geometrical structures of the molecules below? What is the molecular geometry, polar or nonpolar, and if.
Transcript: For the CH4O Lewis structure, we have 14 valence electrons. So there are a number of ways to draw the Lewis structure for CH4O in which each of the atoms has a full outer shell and we only use 14 valence electrons.
A: C2H2 has a straight-line molecular geometry consisting of a hydrogen atom bonded to a carbon atom, which is triple-bonded to a second carbon atom bonded to.
Apr 25, 2015 · This molecule is Methanol and has two geometric centers – the Carbon and the Oxygen. CH3OH The carbon is tetrahedral electron geometry and tetrahedral molecular geometry The Oxygen is tetrahedral electron geometry and bent molecular

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Retrieved Text: An oxygen atom has 6 electrons in its outer shell. Oxygen is in group 6 of the periodic table. A carbon atom has 4 electrons in its outer shell. Carbon is in group 4 of the periodic table. Two oxygen atoms and 1 carbon atom will each share two electrons to form four covalent bonds and make a carbon dioxide molecule (CO 2). This is a picture of a carbon dioxide molecule. By sharing the four... A molecule of oxygen contains two atoms. Oxygen never exists freely in nature but rather exists as a diatomic molecule, meaning two oxygen atoms bond together and share electrons.
Oxygen atoms make up almost a quarter of the air on Earth, and they�re necessary for all animals (including people) to breathe. Some oxygen atoms combine with carbon atoms to make carbon dioxide, which plants breathe.
See more What others are saying "Boron Atomic Model Boron Atomic Model Source by mfince" "sixth grade model of an atom oxegyn" "ideas for chemistry projects How to Make a Model of Sodium"
The orbits of each atom's electrons must become linked, and to do that we must have a sudden burst of energy to get these shy things to hook up. �Since hydrogen is extremely flammable and oxygen supports combustion, it wouldn't take much to create this force.
The gaseous compound carbon monoxide, or CO, is formed when one atom of carbon chemically combines with one atom of oxygen during incomplete combustion.

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Retrieved Text: The electronic structure of an atom plays the major role in its chemistry.
Elements consist of only one kind of atom and cannot be decomposed into simpler substances. Our planet is made up of some 90 elements. (Tiny amounts — sometimes only a few atoms — of additional elements have been made in nuclear physics laboratories, but they play no role in our story). Of these 90, only 25 or so are used to build living things. The table shows the 11 most prevalent elements in the lithosphere (the earth's crust) and in the human body.
For example, hydrogen, carbon, and nitrogen together represent less than 1% of the atoms found in the earth's crust but some 74% of the atoms in living matter.
one of the properties of life is to take up certain elements that are scarce in the nonliving world and concentrate them within living cells.
Some sea animals accumulate elements like vanadium and iodine within their cells to concentrations a thousand or more times as great as in the surrounding sea water. It has even been proposed that uranium be "mined" from the sea by extracting it from certain algae that can take up uranium from sea water and concentrate it within their cells.
There is still some uncertainty about the exact number of elements required by living things. Some elements, e.g., aluminum, are found in tiny amounts in living tissue, but whether they are playing an essential role or are simply an accidental acquisition (aluminum probably is) is sometimes difficult to determine.
Each element is made up

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Retrieved Text: Propane is a fossil fuel and a component of natural gas. Over millions of years it formed from the organic remains of organisms and is mined from underground deposits. Propane gas is an organic compound made of three molecules of carbon atoms bonded with eight hydrogen atoms. The type of carbon-carbon carbon-hydrogen bonds determines the structure of propane molecules, which follows the same pattern as other types of natural gasses like methane and butane.
The chemical formula of propane is C3H8.
Propane is classified as an organic compound because it contains carbon. It is further categorized as a hydrocarbon because it belongs to a group of organic compounds that are made of only carbon and hydrogen. More specifically, propane is a type of hydrocarbon called an alkane. The atoms in alkane molecules are held together by single covalent bonds, and carbon atoms always form four covalent bonds.
Alkanes follow a general formula with a set ratio of carbon atoms to hydrogen atoms: C_nH2_n+2. The simplest alkane is methane, otherwise known as natural gas. It contains one carbon atom bonded to four hydrogen atoms. For methane, n = 1, so the number of hydrogen atoms it has is equal to 2(1)+2 which equals 4. Ethane contains two carbon atoms bonded together, and each carbon is bonded to three hydrogen atoms for a total of six hydrogen atoms. Propane has chain of three carbon atoms, with a chemical formula of C3H8, because a chain of three carbons require 2(3)+2 hydrogen atoms, which equals eight. Butane, another common alkane used as fuel

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Retrieved Text: Use molecular model kits to construct an ethylene molecule, a sulfuric acid molecule and a water molecule.
Break open the double bond of the ethylene molecule and add a hydrogen atom from the sulfuric acid to one carbon atom, and the HSO4 group to the other carbon atom, forming the molecule CH3CH2HSO4.
Break the water molecule into a hydroxy group and a hydrogen atom.
Replace the HSO4 group in the CH3CH2HSO4 molecule with the hydroxy group.
Combine the HSO4 group with the hydrogen atom from the water to reform the sulfuric acid molecule.

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Retrieved Text: An intermediate with tetrahedral geometry. This type of intermediate is formed when a nucleophile attacks the carbonyl group of a carboxylic acid derivative.
A reaction intermediate where the bond arrangement around an initially double-bonded carbon atom has been transformed from trigonal to tetrahedral. Tetrahedral intermediates that make nucleophilic addition to a carbonyl group.

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Retrieved Text: Carbon is termed to be an element of enormous importance to us in both elemental and combined form. Food, clothes, medicines, books, and many of the things are based on this element carbon. Also all the living structures are carbon based. Only 0.02% carbon is found in earth’s crust. Carbon is found in minerals like hydrogen carbonates, carbonates, coal and petroleum. 0.03% of carbon dioxide is present in the atmosphere. Though it is available in very small amount, its importance is very large.
Most of the carbon compounds are found to be poor conductors of electricity. Carbon compounds have covalent bonds between them. Covalent bond is a bond that is formed by sharing an electron pair between two atoms. Carbon compounds behave as poor conductors of electricity because of the presence of covalent bond between them. Carbon atoms form covalent bonds between themselves and with the atoms of other elements also.
Allotropy is defined as the property of some chemical elements to exist in two or more different forms. The two different allotropes of carbon are diamond and graphite. In diamond, each carbon atom is bonded to other four carbon atoms forming a rigid 3-dimensional structure while in the case of graphite each carbon atom is bonded to other three carbon atoms in the same plane giving a hexagonal array.Fullerene is also an allotrope of carbon containing clusters of 60 carbons joined together to form a sphere (similar to the football) and this allotrope is also called as buckminsterfullerene.
1 - Carbon has the distinctive capability to form bonds

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Retrieved Text: Take the prefix that corresponds to the total number of carbon atoms in the molecule (see naming alkanes in the alkanes page) and add anoic acid to form the name, e.g. CH3COOH is ethanoic acid.
With all these reactions a metal carboxylate salt is formed (e.g. sodium ethanoate).
When carboxylic acids are mixed and heated with alcohols, with a little concentrated sulphuric acid as a catalyst to remove the water product, esters are produced.
The reaction needs to be conducted in distillation appartus so that the product can be separated from the carboxylic acid starting material.
To name an acyl chloride take the prefix that corresponds to the total number of carbon atoms in the molecule (see naming alkanes in the alkanes page) and add anoyl chloide to form the name, e.g. CH3CH2COCl is propanoyl chloride.
Acyl chlorides perform the same reactions as their parent carboxylic acids, except that they react at room temperature and generate hydrogen chloride as a byproduct. They give very exothermic reactions. They must be kept in a dry atmosphere as they will react with the slightest amount of moisture to regenerate the carboxylic acid.
The carboxylic acid is refluxed with a dehydrating agent, such as phosphorus pentoxide (P2O5) and the product is distilled from the reaction mixture.
To name an acid anhydride take the prefix that corresponds to the total number of carbon atoms in the parent carboxylic acid (see naming alkanes in the alkanes page) and add anoic anhydride to form the name, e.g. (CH3CH2CO)2O is propanoic anhydride.
As with acyl chlorides, they perform the same reactions as

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Retrieved Text: Acetylacetone is the simplest of the β-diketones and supports the phenomenon we call keto-enol tautomerism (see the illustration). Notice that the third carbon atom in the 5-carbon keto chain loans one of its hydrogen atoms in forming the enol tautomer.
The freedom to move of this hydrogen atom suggests acetylacetone is a weak acid.¹ In effect, the saturated di-ketone becomes an unsaturated di-alcohol. Only instead of two hydrogen atoms, one to each oxygen atom, there is just the one hydrogen atom that must be shared.
Commercially, acetylacetone or H(acac) can be prepared from isopropenyl acetate by heating it in the presence of an appropriate metal catalyst.
Since it is an acid, it can ionize or “disassociate”, giving a positive hydrogen ion. What else is produced in the process? The H(acac) also produces the negatively-charged ion (acac)⁻. This ligand (for such it is, especially when it binds to an atom of metal) is bidentate, meaning “two-toothed”. A classic example is Co(acac)₃. Notice how the image shows the three anions “biting” the cobalt atom.
Notice the propeller-like shape and symmetry of the cobalt III acetylacetonate molecule. Also take note it exists as two enantiometers. An enantiomer is defined as each of a pair of two molecules that exist as mirror images of each other. Such mirror images are not superimposable.
Complex compounds such as Co(acac)₃ are often studied for unusual applications. One potential application for Co(acac)₃ is the formation of alloy nanoparticles that possess magnetic properties. See, for example, the reference cited for Chen and Nikles, cited below.
¹ We simplify our discussion by

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Retrieved Text: A ketone is an organic compound that has a carbon atom with a double bond to an oxygen atom (this is called carbonyl functional group). This carbon atom must also have single bonds to two other carbon atoms.
A ketone can be produced by oxidating a secondary alcohol.
A ketone will show a strong peak between 1690 and 1715cm-1 using infrared spectroscopy.
↑ Padias, Anne. Making the Connections: A How-to guide for Organic Chemistry Lab Techniques. 2nd. Plymouth: Hayden-McNeil, 2011. pp 73. Print.
This page was last changed on 14 March 2019, at 11:04.

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Retrieved Text: How glucose convert into fructose through enolization?
Why is enol form preferred in contrast to the keto form in the keto enol tautomerism of dicarbonyl compound?
I think because it can then make hydrogen bonds which are morestable than the polar interactions it would make in the keto form.
What is the Difference between enolate ion and carbanion?
How you get keto form from enol form?
How vinyl chloride and acetyldehyde are keto enol tautomers?
Is it normal for enole not to eat a day?
An enol is an organic compound containing a hydroxyl group bondedto a carbon atom, doubly bonded to another carbon atom.

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Retrieved Text: In chemistry, a compound is formed when atoms from two or more different elements form a chemical bond.
An ionic bond, for instance, involves the transfer of an electron from one atom to another. Essentially, one atom is gaining an electron while another atom is losing an electron.
Another type of bond- covalent- occurs when atoms share electrons.
In our daily lives, chemical bonds occur around us constantly. The rain (H2O) falling outside your window, the sugar (C12H22O11)in your coffee, and the carbon dioxide (CO2) you exhale are all examples of chemical bonds.
Hunter Hickox, a May 2018 PhD graduate in the Department of Chemistry, works at the fundamental chemical level to discover both unidentified compounds and unknown ways these compounds can form bonds.
Part of the Robinson research group led by Dr. Gregory Robinson, Hickox investigates the chemistry of main group elements. The most abundant elements on Earth, the group includes: Sodium (Na), Potassium (K), Calcium (Ca), Aluminum (Al), Carbon (C), Nitrogen (N), Oxygen (O), Sulfur (S), and Silicon (Si).
Most elements have a favored oxidation state that is primarily what exists in nature.
Generally, elements from the main group are in a positive formal oxidation state, which means they lack electrons. For example, in silicon tetrachloride, SiCl4, the silicon atom is in the plus four oxidation state, and each chlorine atom is in the negative one oxidation state.
The research group primarily focuses on synthesizing new compounds with low-oxidation state main group elements.
To create these low-oxidation state main group elements, Hickox works to perform reductions, or a lowering of the oxidation state.
In

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Input Text: Answer the following question given this paragraph: 

The Appendicular Skeleton The appendicular skeleton includes all bones of the upper and lower limbs, plus the bones that attach each limb to the axial skeleton. There are 126 bones in the appendicular skeleton of an adult. The bones of the appendicular skeleton are covered in a separate chapter.


Q: The appendicular skeleton includes all bones of the upper and lower limbs, plus the bones that attach each limb to the what?

 Choices:

- compressed skeleton

- dynamic skeleton

- literal skeleton

- axial skeleton

A:

Target Text: axial skeleton

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Retrieved Text: The word axial is from the word axis, and refers to how the bones of the axial skeleton are located along the central axis of the body. The axial skeleton functions to support and protect the organs of the dorsal and ventral cavities.... 122 Exercise 9 9 T he axial skeleton (the green portion of Figure 8.1 on p. 108) can be divided into three parts: the skull, the ver-tebral column, and the thoracic cage.
The appendicular skeleton includes all bones of the upper and lower limbs, plus the bones that attach each limb to the axial skeleton. There are 126 bones in the appendicular skeleton of an adult. The bones of the appendicular skeleton are covered in a separate chapter.... The appendicular skeleton of 134 bones and the axial skeleton of 80 bones together form the complete skeleton of 206 bones in the human body. Unlike the axial skeleton, the appendicular skeleton is unfused. This allows for a much greater range of motion.
The appendicular skeleton of 134 bones and the axial skeleton of 80 bones together form the complete skeleton of 206 bones in the human body. Unlike the axial skeleton, the appendicular skeleton is unfused. This allows for a much greater range of motion.... The axial skeleton consists of the bones along the central axis of the human body. There are six bones which make up � well, not six bones, but six things that you need to remember that make up the axial skeleton.
The axial skeleton includes the three major regions that form the

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Retrieved Text: The human skeleton is the internal framework of the body. It is composed of 270 bones at birth – this total decreases to 206 bones by adulthood after some bones have fused together. The bone mass in the skeleton reaches maximum density around age 30. The human skeleton can be divided into the axial skeleton and the appendicular skeleton. The axial skeleton is formed by the vertebral column, the rib cage, the skull and other associated bones. The appendicular skeleton, which is attached to the axial skeleton, is formed by the shoulder girdle, the pelvic girdle and the bones of the upper and lower limbs.
It is a life-size human skeleton model that is great for anatomical study. It can be mounted on roller stand for convenient display.

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Retrieved Text: Time to bone up on the human skeleton, kids! So how exactly does this fragile internal structure that keeps us upright and keeps our head on our shoulders operate? First things first: in Bones, kids will be surprised to learn that by the time they’re 20, they will have almost a hundred fewer bones than when they were born. (Read this issue to find out why!) They’ll also find out what bones have in common with rocks, and read about the five types of bones and what they do; among other things, some help make blood, some protect nerves, and some help keep our organs in place.
The human skeleton, for kids, gets the full run-down here; they’ll learn about the axial skeleton, which includes the all-important spinal cord, and the appendicular one, which makes up the bones of our limbs. Moving on to the animal world, kids will enjoy reading about how salamanders can grow back missing limbs, and why antlers are bones, but horns are not. They’ll be intrigued by diagrams showing how fossils are made, and be surprised to find out that ancient Egyptians used ground-up mummies in medicines. Wrapping things up is a section describing bone maladies and the healing process of the human skeleton; for kids curious about X-rays, there are also some great images of hands and animal skeletons that reveal these incredible structures in colorful detail.

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Retrieved Text: Together, the bones and muscles make up the musculoskeletal system.
A bone is classified by its shape. A bone is enclosed by a tough, fibrous, connective tissue covering called the periosteum. A joint is where a long bone contacts another bone and it is covered by a layer of cartilage.
The primary connective tissues of the skeleton are bone, cartilage, and dense fibrous connective tissue. All connective tissues contain cells separated by a matrix that contains fibers.
Bone tissue is strong because the matrix contains mineral salts, notably calcium phosphate. Compact bone is highly organized and composed of tubular units, by comparison spongy bone has an unorganized appearance. Bones contain yellow bone marrow, which contains a large amount of fat. The spaces of spongy bone are often filled with red bone marrow, a specialized tissue that produces all types of blood cells.
Cartilage is not as strong as bone, but it is more flexible because the matrix is gel-like and contains many collagenous and elastic fibers. There are three types of cartilage, all of which are associated with bones: hyaline cartilage, fibrocartilage, and elastic cartilage.
Ligaments bind bone to bone while tendons connect muscle to bone at joints, both of which are dense fibrous connective tissue.
Bones are composed of living tissues.
The bones of the human skeleton, except those of the skull, first appear during embryonic development as hyaline cartilage. The cartilaginous structures are then gradually replaced by bone, a process called endochondral ossification.
In the adult, bone is continually being broken down and built up again, a process called remodeling.
The functions of

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Retrieved Text: The adult human skeleton is made up of 206 bones, and is divided into two main divisions: the axial and appendicular. The axial skeleton consists of the bones along the axis of the body. The appendicular skeleton consists of the bones of the appendages (arms and legs) and the girdles (shoulder and pelvic) that connect them with the axial skeleton.

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Retrieved Text: The shoulder girdle or pectoral girdle is the set of bones in the appendicular skeleton which connects to the arm on each side. In humans it consists of the clavicle and scapula; in those species with three bones in the shoulder, it consists of the clavicle, scapula, and coracoid. Some mammalian species (such as the dog and the horse) have only the scapula.
The pectoral girdles are to the upper limbs as the pelvic girdle is to the lower limbs; the girdles are the parts of the appendicular skeleton that anchor the appendages to the axial skeleton.
In humans, the only true anatomical joints between the shoulder girdle and the axial skeleton are the sternoclavicular joints on each side. No anatomical joint exists between each scapula and the rib cage; instead the muscular connection or physiological joint between the two permits great mobility of the shoulder girdle compared to the compact pelvic girdle; because the upper limb is not usually involved in weight bearing, its stability has been sacrificed in exchange for greater mobility. In those species having only the scapula, no joint exists between the forelimb and the thorax, the only attachment being muscular.
The shoulder girdle is the anatomical mechanism that allows for all upper arm and shoulder movement in humans. The shoulder girdle consists of five muscles that attach to the clavicle and scapula and allow for the motion of the sternoclavicular joint (connection between sternum and clavicle) and acromioclavicular joint (connection between clavicle and scapula). The five muscles that comprise the function of the shoulder

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Retrieved Text: Hydrostatic skeletons: Found in creatures such as worms and jellies, hydrostatic skeletons are basically chambers filled with water. Animals with this skeleton type move and change their shape by squeezing their water-filled chambers — just like what happens when you squeeze a water balloon.
Exoskeletons: These are exactly what they sound like — skeletons on the outside of the body. You’re probably quite familiar with these hard exterior coverings because they’re found on crabs, lobsters, and many insects. Exoskeletons are rigid and can’t expand as animals grow, so animals must molt, or shed, their exoskeletons periodically. After an animal molts, its new exoskeleton is soft — as in a soft-shelled crab.
Endoskeletons: The most familiar of all skeleton types is the endoskeleton. After all, it’s the kind of skeleton you have. An endoskeleton exists within an animal’s body. The human endoskeleton is hard because it’s partially constructed of the mineral calcium. The endoskeletons of other animals may be more flexible — for example, the endoskeleton of a shark is made of cartilage, the same material that makes up the soft parts of your nose.
Animals with hydrostatic skeletons and exoskeletons are considered invertebrates, meaning they don’t have a backbone. Animals with endoskeletons, like you, are considered vertebrates because they have a backbone.
All vertebrate skeletons— whether they belong to humans, snakes, bats, or whales — developed from the same ancestral skeleton (which explains why you may notice similarities between your skeleton and that of your pet dog or cat). Today, these animals show their relationship to each other in part

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Retrieved Text: This part of the interactive anatomic atlas of the human body is devoted to the arterial vasculature of the pelvic girdle, pelvis, thigh, knee, leg and foot and to the study of bones and joints. It includes a 3D reconstruction of bones and arteries from angioCT with injection of a contrast agent (iodine), an angiographic view correlated with the 3D view and digital radiography of the skeleton of the lower limb.
We have selected a normal angioCT (Computed Tomography) exam of lower limbs: acquisition was made with helical multidetector CT (MDCT) after injection of iodized contrast. The axial images were post-processed using software post-treatment on a workstation for a multimodal reconstruction and a three-dimensional visualization of bone and blood vessels, then a similar angiographic view was created.
The DICOM images were exported and then integrated into the software Adobe CS3 Professional Flash to create this anatomic module. The anatomical structures were labelled on the 3D view.
We also selected non pathologic digital X-rays: pelvis, hip, knee, ankle and foot, labelling the skeletal structures and joints.
All anatomical structures of the Terminologia Anatomica are translated in French, English, Spanish, Portuguese, Russian, Czech, Japanese and Chinese. This module may be used as a medical dictionary.
We preferred to use an angioCT of the lower limb rather than a digital arteriography because it allowed the user to make a correlation between angiographic views of arteries with three-dimensional structures.
The 3D/angiographies tab can be used to select these two kinds of view.
We have segmented the legends of the arteries into different groups: aorta and its branches,

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Retrieved Text: Overview of the Lower Limb. In: Morton DA, Foreman K, Albertine KH. Morton D.A., Foreman K, Albertine K.H. Eds. David A. Morton, et al.eds. The Big Picture: Gross Anatomy, 2e New York, NY: McGraw-Hill; . http://accessphysiotherapy.mhmedical.com/content.aspx?bookid=2478&sectionid=202021720. Accessed April 21, 2019.
. "Overview of the Lower Limb." The Big Picture: Gross Anatomy, 2e Morton DA, Foreman K, Albertine KH. Morton D.A., Foreman K, Albertine K.H. Eds. David A. Morton, et al. New York, NY: McGraw-Hill, , http://accessphysiotherapy.mhmedical.com/content.aspx?bookid=2478&sectionid=202021720.
The bones of the skeleton provide a framework that serves as an attachment for soft tissues (e.g., muscles). The bony structure of the gluteal region and thigh, from proximal to distal, consists of the pelvis, femur, patella, tibia, and fibula (Figure 34-1A). Synovial joints and fibrous ligaments serve to connect bones together.
A. Skeleton of the lower limb. B. Osteology of the os coxa (pelvic bone). C. Femur.
Articulations. The pelvic bones articulate posteriorly with the sacrum via the sacroiliac joints, and anteriorly with each other at the pubic symphysis.
Constituents. Each pelvic bone consists of three bones: ilium, ischium, and pubis.
Acetabulum. A large cup-shaped structure at the junction where the ilium, ischium, and pubis fuse. The acetabulum protrudes laterally for articulation with the head of the femur bone.
Obturator foramen. An opening formed by the ilium, ischium, and pubis.
The ilium is the most superior and the largest bone of the three components of the pelvis.
Iliac fossa. Attachment site for the iliacus muscle.
Iliac crest. A prominent, palpable crest between the ASIS and PSIS where numerous body wall and limb muscles attach; possesses a large amount of

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Retrieved Text: An osteocartilaginous exotosis is commonly known as an osteochondroma which is a benign bone tumour. Growing tumors might end up replacing healthy tissues with abnormal tissue. It could end up weakening the bone and cause it to break (fracture). Most of the time, the bone tumor is noncancerous (benign), but there are very rare instances where the tumor transforms into being cancerous (malignant). If the tumor is benign, it is not usually life-threatening. A malignant tumor could end up spreading cancerous cells throughout the body (metastasize), which can happen through the lymphatic system or the blood.
To gain a better understanding of a bone tumor, you need to understand the bone anatomy. The skeletons living structure works to support the entire body. Bones are composed of an outer shell that is a dense bone surrounding the honeycomb structure of the softer bone. Calcium and protein make up the bone. If bones don’t have calcium, they will end up becoming weak.
Axial skeleton – The axial skeleton has 80 bones in total that include the chest, skull and spine.
Appendicular skeleton – This skeleton has 126 different bones including that of the limbs, hands, feet and pelvic girdle.
How Do You Know if You Have an Osteocartilaginous Exotosis?
First think to yourself, how did the pain start? Was their a logical reason (e.g. a trauma, accident or injury)? If there was no logical reason and the pain came on gradually, a bone tumour is more likely. Secondly, you may also have one of a number of other symptoms association with it such

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Retrieved Text: The understanding of normal growth and development of the musculoskeletal system is fundamental for the evaluation of the wide spectrum of congenital and developmental abnormalities in children. This knowledge is essential for accurate identification of imaging findings, differential diagnosis, classification, and therapeutic guidance. In this chapter, the currently available various imaging modalities and their main uses in pediatric patients are discussed. The normal anatomy of the developing skeleton is reviewed. An overview of the important imaging characteristics of skeletal abnormalities and syndromes related to skeletal growth and development is provided. In addition, a concise description of the underlying pathophysiology, imaging diagnosis, and therapeutic approaches are also presented.
The role of ultrasound (US) in musculoskeletal imaging is currently expanding beyond the evaluation of the infant hips. The lack of ionizing radiation exposure or need for sedation, wide availability of US equipment, and the advantage of tailored examinations with both static and dynamic components are all strengths of US, in particular for neonates and young children with abundant hyaline cartilage. Prenatal US is the primary method for evaluation of the fetus and is not unusual to first suspect a potential skeletal dysplasia during routine US examination following identification of shortened long bones or other abnormal skeletal findings.3,4 However, the accurate prenatal diagnosis of skeletal dysplasias remains challenging because of the heterogeneity of this group of relatively rare disorders, variability in the time of manifestation of clinical findings, and frequent lack of a corroborating genetic and molecular diagnosis.5,6,7 A multidisciplinary approach among radiologists, clinicians, pathologists, and geneticists is crucial for

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Retrieved Text: The Lower Limb Skeleton System is divided into three regions. In the lower limb Two major joint are hip joint and knee joint. The lower limb contains 31 bones. These are the Innominate bone, femur, patella, tibia, fibula, tarsal bones, metatarsal bones, and phalange.

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Retrieved Text: Teaching your child to reduce, reuse and recycle is important, but it doesn't have to be monotonous. Help your child make a skeleton out of recycled milk jugs and wire for a fun and educational craft. You will need a supply of plastic milk jugs to complete this project. You can save your own containers over several weeks or visit the neighbors with your child to ask for recycled donations. For extra pizzazz, decorate the skeleton with glow-in-the dark paints and recycled bottle caps for his eyes, nose and mouth.
Turn the first milk jug upside down, and cut two slits in the top (the base of the jug). Lace a piece of wire through the slits, and twist the ends together to hang the skeleton. On the side opposite the handle, glue recycled bottle tops to make eyes, a nose and a mouth.
Hold the second jug right-side up. On the side opposite the handle, cut two parallel sets of slits going down the jug about 1/2 inch apart. The slits should be 2 to 3 inches wide. Make a ring of hot glue around the spout of the first jug and attach the spout of the second jug -- positioned so that their handles are aligned on the same side. Hold the spouts together for at least 1 minute to allow the glue to dry.
Trace a semicircle around the top of the handle of a new jug. Cut around the semi-circle and under the handle to detach it from the carton. Detach the rest of the

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Retrieved Text: There is a vast volume of data that provide strong support for the theory of evolution. �Evolution, as with all scientific theories, are based on a large volume of data that has been collected by many researchers over a long period of time. For the HSC course, you must demonstrate an understanding of the different lines of evidence, including how that evidence is interpreted.
Palaeontology is the study of fossils. �Indeed, fossils were one of the things that Charles Darwin studied extensively. �Well before Darwin had embarked on his famous voyage, he was already aware that the Earth was very old. �Indeed, geologists before Darwin had come to the conclusion that the Earth was hundreds of�thousands years old, if not more. When people examined fossils, they realised that fossils were similar to the bones of many animals. �Some fossils also resembled insect exoskeletons. They concluded that fossils were the bodily remains of animals that had existed in the past. �One thing was obvious: some of the animal looked very different to the bones of present-day animals. �The same was true of plant fossils. �So, they came to the conclusion that the fossil record suggested that life on Earth was very ancient, and they many of the organisms that lived in the distant past looked very different to present-day ones.
Crossoptergerian fossils are the remains of fish that show adaptation to life on land. �Their fins are lobed and contain bones. �This indicates that the lobed fins of this animal could have functioned as limbs for movement (perhaps on

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Retrieved Text: Free printable human skeleton worksheet for students and teachers teachers. Bones and muscles worksheet of the lower limb anatomy physiology. Collection of human skeletal system worksheets bloggakuten bloggakuten. Worksheets bones worksheet pureluckrestaurant free for printable of the body anatomy organ worksheet. Bones of the body worksheets for all download and share free on bonlacfoods com.

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Retrieved Text: The morning after a spring gale is an ideal time to walk along the beach to see what has washed ashore. Scan the debris and you might find seal and whale bones.
The morning after a spring gale is an ideal time to walk along the beach to see what has been washed ashore.
Scan the accumulated debris for mammal bones – many of these will be the remains of domestic animals washed out to sea, but among them you should spot seal and whale bones. Stephen Harris explains how to identify what you find.
Make a reference collection of the bones you find – it will aid identification later on.
Most bones will have been cleaned and bleached by the sun, but any that need a wash can be soaked in a commercial denture cleaner or gently boiled in a solution of sodium perborate.
Never use bleach – it dissolves the bone.
There are several books that will help you identify your finds, but expect the unexpected. You may well discover the remains of exotic mammals that have died at sea and been thrown overboard, or drifted a long way outside their normal range.
Seal skulls are superficially dog-like in appearance.
Common seal skulls are about 23cm long; grey seals 27cm.
A grey seal skull has a long, wide, high snout that’s associated with its ‘Roman’ nose.
The cheek teeth of common seals have three distinct cusps. Grey seals have either a single cusp or small additional cusps.
Limb bones of both species are short and powerful, with bones of lower limbs flattened.
Toothed whales have a

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Retrieved Text: In this “Bones of the Body” video part you will discover the anatomy of the forearm and the hand.
We continue the “Bones of the Body” discovery.
Below the elbow is the forearm. The arm bone is called the humerus. At the elbow end, the humerus has two projections, called the lateral epicondyle and the medial epicondyle. In anatomy, the word ‘lateral’ stands for ‘on the outside’ and the word ‘medial’ stands for ‘on the inside’.
The medial epicondyle is more prominent than the lateral epicondyle. The flexor muscles of the lower arm attach to the medial epicondyle. This bony projection is visible on our arms near the elbow. Keep this in mind when you are making a drawing of a model.
The lateral epicondyle is noticeable only when the arm is flexed; otherwise it is hidden by muscles. This protrusion serves as the attachment for the exterior muscles of the lower arm.
The two bony structures on the lower end of the humerus are called the capitulum and the trochlea; they are part of the elbow joint.
Bones of the Body include two bones of the forearm, which are called the ulna and the radius. The radius is shorter than the ulna, and the ulna is shorter than the humerus; so the humerus is the longest bone of the arm.
In the anatomical position of the Bones of the Body, the radius and the ulna are parallel to each other. The ulna is located on the little finger’s side, while the radius is on the thumb side of the hand.
The upper part

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Retrieved Text: Long bones of the appendicular skeleton are formed from a cartilage template in a process known as endochondral bone development. Chondrocytes within this template undergo a progressive program of differentiation from proliferating to postmitotic prehypertrophic to hypertrophic chondrocytes, while mesenchymal cells immediately surrounding the early cartilage template form the perichondrium. Recently, members of the Wnt family of secreted signaling molecules have been implicated in regulating chondrocyte differentiation. We find that Wnt-5a, Wnt-5b and Wnt-4 genes are expressed in chondrogenic regions of the chicken limb: Wnt-5a is expressed in the perichondrium, Wnt-5b is expressed in a subpopulation of prehypertrophic chondrocytes and in the outermost cell layer of the perichondrium, and Wnt-4 is expressed in cells of the joint region. Misexpression experiments demonstrate that two of these Wnt molecules, Wnt-5a and Wnt-4, have opposing effects on the differentiation of chondrocytes and that these effects are mediated through divergent signaling pathways. Specifically, Wnt-5a misexpression delays the maturation of chondrocytes and the onset of bone collar formation, while Wnt-4 misexpression accelerates these two processes. Misexpression of a stabilized form of beta-catenin also results in accelerated chondrogenesis, suggesting that a beta-catenin/TCF-LEF complex is involved in mediating the positive regulatory effect of Wnt-4. A number of the genes involved in Wnt signal tranduction, including two members of the Frizzled gene family, which are believed to encode Wnt-receptors, show very dynamic and distinct expression patterns in cartilaginous elements of developing chicken limbs. Misexpression of putative dominant-negative forms of the two Frizzled proteins results in severe shortening of the infected cartilage elements due to

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Retrieved Text: ‘Downward Facing Dog is the garlic of yoga,’ said Donna Farhi. The reason for the analogy she explained, is that just as garlic enhances a dish, Downward Facing Dog enhances asana practice. Benefits include – lengthening muscles in the backs of legs, strengthening hands, arms, shoulders and core; in addition, it’s a mild inversion and can have a neutralising effect on the spine.
There are many concepts and beliefs as to how the pose should be practised. My own aims for the practice and teaching of Downward Facing Dog, will always involve clear pathways of weight through the bones and the facilitation of breath movement through the body. Alongside these aims, it’s good to find a springy, lively quality that can be transferred from the hands, via upper limbs, shoulder girdle, spine, ultimately through lower limbs and to the feet. An important premise to bear in mind when practising asana – Downward Facing Dog in particular – is that the hands and upper limb bones belong with the shoulder blades (scapulae), the feet and lower limb bones belong with the two pelvic halves, the spine belongs with the sacrum and tail. Our embryological development informs this premise.
Now try Downward Facing Dog as follows and see how it feels!
Hands – begin with your hands on the mat – shoulder width is a good place to start but move them slightly wider, or closer together if you need to. Organise your hands so that your fingers (phalanges) are aligned with the longer bones of your hands (the metacarpals). Aim

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Retrieved Text: In this post we head back for the final days of the Bay Area Equestrian Club’s Vet Camp. Day four began with campers designing their own equestrian centre.
You need math to stay within your budget and calculate what it will cost to build an equestrian centre or vet hospital.
1. If you designed a 10 horse barn with base dimensions of 36 ft (11 m) by 84 ft (26 m), what is the perimeter of the barn?
2. What is the area of the barn?
3. To calculate the amount of wood you would need to build the exterior (outside) walls, would you use the area of the barn or the perimeter?
A form of yoga created specifically for horseback riders was taught in the barn. Good thing this barn has a super-wide isle!
A standard size for a box stall is 12 ft (3.7 m) x 12 ft. (3.7 m).
4. How many stalls would fit down the length of an 84 ft (26 m) long barn?
Of course barns and stables need more than just stalls. Caden explains, “You may have a tack room and closet in the barn and you may also need enough room for a hay loft or a grooming stall.
Campers also learned about pasture and paddock size. For example, each horse should have approximately ½ acre of space to roam.
5. Is ‘acre’ a measure of area or perimeter?
6. Assuming each horse gets ½ acre of space, if Caden’s dream equine centre devoted 25 acres to pasture and paddocks, how many horses would she have room for?
Learning the

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Retrieved Text: Mark Hill (talk) 11:32, 10 September 2017 (AEST) Reorganised lecture structure for online presentation.
appendicular skeleton - the part of the human skeleton is associated with the limbs, the appendicular skeleton.
axial skeleton - the part of the human skeleton consisting of the skull, auditory ossicles, hyoid bone, vertebral column, sternum and ribs. image The other part of the human skeleton is associated with the limbs, the appendicular skeleton.
canaliculi - (singular, canaliculus) small channel in the bone matrix in which an osteocyte process lies and communicates with other osteocytes and the Haversian canal. Allow osteocytes to communicate with each other and to exchange substances by diffusion.
cartilage - connective tissue from mesoderm in the embryo forms most of the initial skeleton which is replaced by bone. In adult, found on the surface of bone joints.
centrum - the primordium of the vertebral body formed initially by the sclerotome.
clavicle - (Latin, clavicle = little key) bone which locks shoulder to body.
Cobb angle - clinical term for measuring axial skeleton abnormality. Measures coronal plane deformity on antero-posterior plain radiographs in the classification of scoliosis. Named after the American orthopedic surgeon John Robert Cobb (1903 - 1967).
desmal ossification - (intramembranous ossification) the process of mesenchyme directly ossifying into bone without a pre-existing cartilage template. Vascularised regions of mesenchymal cells proliferate and differentiate into pre-osteoblasts and then osteoblasts, occurs in parts of the skull and the clavicle.
diaphysis - anatomical term that refers to the shaft of long bones.
endochondrial ossification - the process of replacement of the cartilagenous framework by osteoblasts with bone.
endosteum - inner

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Retrieved Text: The limb bones of tetrapods exhibit a wide range of shapes and sizes. Because locomotion is one of the most frequent and demanding behaviors in which limbs are used, this diversity in limb structure and design is frequently attributed to variation in the mechanical loading patterns that bones experience during locomotion. Limb bones are usually able to withstand loads much higher than they would normally experience before they fail. This margin of protection is known as a 'safety factor.' High safety factors would provide limb bones substantial insurance against failure, but could also make limb bones more costly to grow, maintain, and transport. Research in this area has focused mainly on birds and mammals, animals that use upright limb posture; however, a limited number of studies on reptilian species, in which the limbs are held in a sprawling posture, have shown that their limb bone loading patterns differ substantially from those of birds and mammals. To clarify whether the bone loading patterns observed in non-avian reptiles are ancestral or derived conditions, bone loading data from an additional species would provide a critical perspective. Salamanders are an ideal outgroup (outside the amniote clade) from which such data can be obtained. Additionally, among reptiles, lizards are one of the most diverse groups and among the most (at least superficially) similar in body plan to salamanders. Sampling a lizard species from a different lineage than that previously examined could help to determine whether bone loading patterns are similar across the breadth of lizard taxa and distinct, as a whole,

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Retrieved Text: Master the science behind the arm balances and inversions of Hatha Yoga. Dr. Ray Long guides you on a visual narrative through the anatomy, biomechanics, and physiology of this ancient art, decoding each pose along the way. The Mat Companion series provides you with beautifully illustrated, step-by-step instructions on how to use scientific principles to obtain the maximum benefit from your practice. Each book includes the Bandha Yoga Codex, a simple five-step process that can be applied to any pose to improve strength, flexibility, and precision -- no matter what style of yoga you practice.
Dr. Ray Long rounds out his Mat Companion series with the art and the science behind arm balances and inversions. With this companion guide, practitioners will be able to better understand the anatomy of these more complex poses. Through this scientific approach to arm balances and inversions, practitioners are able to build a stronger knowledge and awareness of the anatomy of this family of poses and deepen their practice.
Contract the adductor group to squeeze the inner thighs against the upper arms. At the same time, engage the lateral deltoids to press the arms outward against the thighs. Activate the triceps to extend the elbows. This links the upper and lower appendicular skeletons and creates a stabilizing bandha in Bakasana.
The axial skeleton is composed of the skull, spine, and ribcage. It links the upper and lower appendicular skeletons. Thus, the two subdivisions of the skeleton can be used to affect and influence each other. For example, in Parsva Bakasana, connecting the thigh to

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Retrieved Text: Prevent Heart Disease by Keeping that Heart Healthy!
Do You Understand the Symptoms and Risks of Cardiovascular Disease?
One common topic in many articles and blog posts about heart health is a call for increased exercise. While we’re all for that healthy lifestyle suggestion, there’s one unintended side effect that can crop up when we hit that track or gym a little too hard. Sometimes our good intention ends up in an ankle sprain, severe muscle strain, or even a broken bone. So let’s wrap up heart month with a quick look at what to do when we experience, or witness, such an injury.
Bones, muscles, and joints give the body shape, allow movement, and protect vital internal organs. Long bones form the upper and lower parts of each limb. Muscles, ligaments, and tendons attach to the bones, allowing for movement where the bones come together at joints. These bones are the most exposed to external forces and injury.
There are four different types of injuries affecting bones, muscles, and joints. Strains are stretching or tearing injuries to muscles or tendons. Sprains are tearing injuries to ligaments that hold joints together. Dislocations are the separation of bone ends at a joint. Fractures are breaks in bones.
Distinguishing an injury to muscle or bone is often difficult. It is best to treat them all as possible fractures. Common signs of these injuries include swelling, pain, and discoloration. The limb may appear deformed and the person may be guarding it by holding it against his or her body.
Unstable bones or joints can damage

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Retrieved Text: We've compiled a glossary of some of the terms you might have heard along your travels.
What does the term 3S mean?
A Suction Silicone Suspension- Utilizes a silicone sleeve with a locking pin to suspend prosthesis.
What does the term Abduct mean?
To move away from the midline of the body.
What does the term Adduct mean?
To move towards the midline of the body.
What does the term AE Trans-Humeral mean?
What does the acronym A.F.O. stand for?
What does the term AK Trans-Femoral mean?
What does the term Alignment mean?
Position of a prosthetic socket in relation to foot and knee.
What does the term Amputation mean?
Removal of all or part of a limb due to infection, injury, tumor, disease, or trauma.
What does the term Anterior mean?
The front of an organism, the ventral surface.
What does the term Amputee mean?
A person who has had all or part of a limb removed/amputated or is born without a limb.
What does the term Atrophy mean?
Reduction in size or wasting away of an organ or cell resulting from disease or inactivity .
What does the term Axial Skeleton mean?
The bones of the skull, vertebral column, thorax, and sternum.
What is a BE Trans-Radial?
What does the term Bilateral mean?
Bi means both, meaning both sides.
What is a BK Trans-Tibia?
What does the term Brachial mean?
What does the term Bursa mean?
Small sac filled with fluid and located at friction points, especially joints.
What does the term Carpal mean?
One of the eight bones of the wrist.
What does the term Cartilage mean?
What does the term Cervical mean?
What does the term Chopart mean?
Amputation of approximately 2/3 of the foot.
What does

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Retrieved Text: Please Take Note: This is a review of the final game, but it might change slightly based on the success of the Kickstarter campaign. The game is being reviewed on the components and the rules provided with the understanding that “what you see is not what you might get” when the game is published. If you like what you read and want to learn more, we encourage you to visit the game publisher’s website. Now that we have all that disclaimer junk out of the way, on with the review.
The Bone Wars (1877 to 1892), also known as “The Great Dinosaur Rush”, was an intense period of scientific prehistoric discovery and bitter rivalry between Othniel Charles Marsh and Edward Drinker Cope. In addition to digging up many bones, many were also destroyed. Theft and bribery were common. Time to join the rush!
The Great Dinosaur Rush, designed by Scott Almes and to be published by APE Games, will reportedly be comprised of 1 Dinosaur Bones bag, 210 Dinosaur Bone pieces (60 green “Body” and “Head” pieces; 50 red “Leg” and “Arm” pieces; 50 yellow “Neck” and “Tail” pieces; 30 blue “Unique Feature” pieces; and 20 grey “Wild” pieces), 1 game board, 21 Bonus cards, 5 Player screens, 5 Player Reference boards, 5 Score tokens, 5 Player pawns, 6 Promotion cubes (black), and 45 Notoriety tokens. As this is a review of a prepublished game, I cannot comment on the game component quality.
Second, give each player 1 Player Screen and 1 Player pawn of the player’s choice. Give

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Retrieved Text: Diabetes has a way of damaging feet without people noticing. High and fluctuating blood sugar levels take their toll on the lower limbs, weakening tissues and deadening nerves. Over time, this makes you far more susceptible to serious and potentially deforming conditions like Charcot foot, which can become deadly if allowed to get out of hand.
Charcot foot is a serious complication of diabetic neuropathy. Nerve damage from fluctuating sugar levels impairs your ability to feel injuries to your lower limbs, so you may not notice when problems develop. High blood sugars also weaken your bones and supportive tissues, making them more prone to damage. The condition develops when the bones in your midfoot crack and begin to break down, but you are unable to feel the change because of the extensive nerve damage in your lower limbs. You continue walking on the injury, worsening it over time. The arch eventually dislocates and collapses, deforming your foot.
Because the nerve damage has to be severe for this to happen, you may only notice some soreness, if any pain at all. Your foot will change, however. It will swell and your skin may appear red. Often your foot will feel warm to the touch. Your lower limb will be weak and difficult to use. The condition only worsens with time, too. Your feet need to be treated promptly to save them; allowing the breakdown to persist can lead to permanent damage and potentially life-threatening complications.
The sooner Charcot foot is diagnosed, the easier it is to manage the problem and

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Retrieved Text: Bones are classified by their shape. Four types of bones are long, short, flat, and irregular.
Muscles can be classified by the type of muscle tissue they are composed of. The three types of tissue are skeletal, smooth, and cardiac.
Long cells (fibers), striated, multi-nucleated. Voluntary motor control. Used to move the skeleton and maintain posture.
Spindle-shaped cells, non-striated, uni-nucleated. Invountary motor control. Found in walls of hollow organs (blood vessels, viscera) to move fluids.
Tubular, branched, striated, uni-nucleated. Invountary motor control. Found in walls of the heart to cause contraction.
Skeletal Muscle is composed of many layers of fibers. At the smallest level, a muscle cell (fiber) is composed of bundles of the protein filaments, actin and myosin. These bundles of filaments are called myofibrils. Several myofibrils are bundled together to form a single muscle cell, also called a muscle fiber. The fiber is covered by a specialized endoplasmic reticulum, called the sarcoplasmic reticulum, which releases Calcuium ions during contraction. The fiber is suurounded by a plasma membrane, called the sarcolemma. Each muscle fiber is surrounded by a layer of connective tissue called the endomysium.
A bundle of muscle fibers is called a fascicle. Each fascicle is surrounded by a layer of connective tissue called the perimysium. A muscle is made up of many fascicles, which are all surrounded by a layer of connective tissue called the epimysium. The epimysium thickens to form a tendon as it connects the muscle to a bone.
During the contraction of skeletal muscle, an electric action potential causes calcium to be released from the sarcoplasmic reticulum,

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Retrieved Text: Scientists have done a compelling research project, revealing how they have accomplished partial toe regeneration in mice using two proteins. This has involved successfully regenerating joints along with the tissue of bones with mice who had lost or damaged toes.
The researchers feel this study shows powerful promise for applying limb regeneration on humans and amputees one day.
The team at Texas A & M University were successful in stimulating growth artificially in amputated and/or injured toes of neonatal mice. This was done using a pair of proteins called BMP-2 and BMP-9.
The joints in the limbs of humans and animals are very complex structurally. This is the case even for creatures in the wild who are able to regenerate their lost limbs but may not have the ability to regrow the joints.
In the past, Ken Muneoka from the University in Texas along with his colleagues were able to regenerate bones in mice after the toes had been removed. This was achieved using the bone growth protein BMP-2, however, the structures at the joints would never develop.
If you want correct limb regeneration then these joint structures need to be regenerated as well.
So the scientists observed that there must be another protein that plays a role in bone regeneration. They wondered if BMP-9 could be the one that is key to developing joints in the limbs.
The team decided to apply the BMP-9 protein to mice after their toes were amputated. The result after three days later showed 60% of the bone stumps had gone on to develop a layer of

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Retrieved Text: An artistic reconstruction of two individuals of Peregocetus, one standing on the rocky shore of modern-day Peru and the other preying on fish. The existence of a tail fluke remains hypothetical.
Named Peregocetus pacificus, which means "the traveling whale that reached the Pacific" in Latin, this recent finding is upending scientists' understanding of how these creatures evolved and spread around the world millions of years ago.
"This is the first indisputable record of a quadrupedal whale skeleton for the whole Pacific Ocean," study co-author Olivier Lambert said in a press release.
But that doesn't mean the animal was good at walking, and "certainly not at running," according to the Los Angeles Times. It likely ate in the water and only took to solid ground for activities like breeding and giving birth, Lambert told the LA Times.
Paleontologists uncovered the animal's bones just inland of Peru's western coast at a site called Playa Media Luna, a three-hour drive south of Lima.
They excavated the whale's tail vertebrae, jaw bones, some of its spine, and its front and hind limbs. The animal's skeleton suggests it was just over 13 feet long, and there's evidence it had a pronounced snout filled with sharp teeth for chomping on fish.
Peregocetus' tail bones appear similar to those of beavers and otters, suggesting that the limb played a large role in swimming, the authors wrote. Unfortunately, the bones from the tip of Peregocetus' tail were missing, so the researchers weren't able to determine whether it had a well-developed tail fluke (like modern whales have) to help propel it

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Input Text: Answer the following question given this paragraph: 

Chapter 11 1 Figure 11.9 Yes, it will be able to reproduce asexually. 2 C 4 D 6 C 8 C 10 C 12 B 14 During the meiotic interphase, each chromosome is duplicated. The sister chromatids that are formed during synthesis are held together at the centromere region by cohesin proteins. All chromosomes are attached to the nuclear envelope by their tips. As the cell enters prophase I, the nuclear envelope begins to fragment, and the proteins holding homologous chromosomes locate each other. The four sister chromatids align lengthwise, and a protein lattice called the synaptonemal complex is formed between them to bind them together. The synaptonemal complex facilitates crossover between non-sister chromatids, which is observed as chiasmata along the length of the chromosome. As prophase I progresses, the synaptonemal complex breaks down and the sister chromatids become free, except where they are attached by chiasmata. At this stage, the four chromatids are visible in each homologous pairing and are called a tetrad. 16 In metaphase I, the homologous chromosomes line up at the metaphase plate. In anaphase I, the homologous chromosomes are pulled apart and move to opposite poles. Sister chromatids are not separated until meiosis II. The fused kinetochore formed during meiosis I ensures that each spindle microtubule that binds to the tetrad will attach to both sister chromatids. 18 a. Crossover occurs in prophase I between non-sister homologous chromosomes. Segments of DNA are exchanged between maternally derived and paternally derived chromosomes, and new gene combinations are formed. Random alignment during metaphase I leads to gametes that have a mixture of maternal and paternal chromosomes. Fertilization is random, in that any two gametes can fuse.


Q: During interphase of what process, each chromosome is duplicated, and the sister chromatids formed during synthesis are held together at the centromere region by cohesin proteins?

 Choices:

- meiosis

- digestion

- mitosis

- apoptosis

A:

Target Text: meiosis

#### Retrieved Documents ####

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Retrieved Text: A cell moves through a series of phases in an orderly manner. During interphase, G 1 involves cell growth and protein synthesis, the S phase involves DNA replication and the replication of the centrosome, and G 2 involves further growth and protein synthesis. The mitotic phase follows interphase. Mitosis is nuclear division during which duplicated chromosomes are segregated and distributed into daughter nuclei. Usually the cell will divide after mitosis in a process called cytokinesis in which the cytoplasm is divided and two daughter cells are formed.
During interphase, the cell undergoes normal processes while also preparing for cell division. For a cell to move from interphase to the mitotic phase, many internal and external conditions must be met. The three stages of interphase are called G 1 , S, and G 2 .
The first stage of interphase is called the G 1 phase , or first gap, because little change is visible. However, during the G 1 stage, the cell is quite active at the biochemical level. The cell is accumulating the building blocks of chromosomal DNA and the associated proteins, as well as accumulating enough energy reserves to complete the task of replicating each chromosome in the nucleus.
Throughout interphase, nuclear DNA remains in a semi-condensed chromatin configuration. In the S phase (synthesis phase), DNA replication results in the formation of two identical copies of each chromosome—sister chromatids—that are firmly attached at the centromere region. At this stage, each chromosome is made of two sister chromatids and is a duplicated chromosome. The centrosome is duplicated during

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Retrieved Text: chromatid A threadlike strand formed from a chromosome during the early stages of cell division. Each chromosome divides along its length into two chromatids, which are at first held together at the centromere. They separate completely at a later stage. The DNA of the chromosome reproduces itself exactly so that each chromatid has the complete amount of DNA and becomes a daughter chromosome with exactly the same genes as the original chromosome from which it was formed.
"chromatid." A Dictionary of Biology. . Encyclopedia.com. 21 Apr. 2019 <https://www.encyclopedia.com>.
chromatid One of the two daughter strands of a chromosome that has undergone division. Chromatids are joined together by a single centromere, usually positioned in the centre of the pair as they lie beside one another. When the centromere divides during the third stage (anaphase) of cell division (mitosis or meiosis), the sister chromatids become separate chromosomes.
"chromatid." A Dictionary of Earth Sciences. . Encyclopedia.com. 21 Apr. 2019 <https://www.encyclopedia.com>.
chromatid One of the two daughter strands of a chromosome that has undergone division. Chromatids are joined together by a single centromere, usually positioned in the centre of the pair as they lie beside one another. When the centromere divides at the anaphase of mitosis or the second stage of meiosis (meiosis II), the sister chromatids become separate chromosomes.
"chromatid." A Dictionary of Zoology. . Encyclopedia.com. 21 Apr. 2019 <https://www.encyclopedia.com>.
chromatid One of the two daughter strands of a chromosome that has undergone division during interphase. Chromatids are joined together by a single centromere, usually positioned in the centre of the pair as they lie

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Retrieved Text: Lulú. “El GIF De La Semana: Mitosis En Tiempo Real.” Esceptica, 22 Jan. 2014, esceptica.org/2014/01/19/el-gif-de-la-semana-mitosis-en-tiempo-real/.
Mitosis and Meiosis sound very similar, but while they share some similar concepts they are two different biological terms. What is Mitosis? Mitosis is cell division creating two “daughter” cells. Daughter cells have the same number of chromosomes and the same kind of chromosomes as the parent cell. What is Meiosis? Meiosis is creating four “daughter” cells that have half of the chromosomes as the parent cell.
While Mitosis and Meiosis both create daughter cells they make two different kinds. Mitosis creates diploid cells or cells that have 23 chromosomes. While meiosis makes haploid cells or gametes which are your reproductive cells such as sperm in males and eggs in females.
Mitosis exists in six different stages each stage doing something different inside of the cell undergoing mitosis.
Interphase: This stage is when the cell is only preparing for Mitosis or Meiosis(Interphase happens in both). This is also where a cell spends most of its life.
Prophase: Prophase is the “first” stage where the nuclear membrane and the nucleus disappear, chromosomes condense and the mitotic spindles form.
Metaphase: This stage is when the duplicated chromosomes line up at the center of the cell. Fun fact this is called the metaphase plate.
Anaphase: Anaphase is when the duplicated chromosomes separate into two identical groups and move towards opposite ends of the cell.
Telophase: This is the second to last stage where membranes form around the two groups of chromosomes at different ends to produce the nuclei in the daughter cells.

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Retrieved Text: During the prophase stage of cell division, chromosomes begin to condense, coil and fold, making them visible under a light microscope. When the duplicated chromosomes continue to coil, the chromosomes are shortened and thickened to a more visible state.... prophase I - meiosis term refers to the first phase of meiosis I, which together with meiosis II results in the reductive cell division only occurring gametes. Prophase can be further divided into a number of stages: leptotene zygotene, pachytene, diplotene, diakinesis.
Go back to prophase 1 and write in alleles for your chromosomes. The drawing below shows what they would look like before they are copied during interphase. Make sure that you write in the alleles on the copied sister chromatids too! a A. B b g G . R r H h. D d. Now, show the alleles of one gene crossing over in one set of homologous chromosomes. Circle the set you chose. Now follow along and... During the prophase stage of cell division, chromosomes begin to condense, coil and fold, making them visible under a light microscope. When the duplicated chromosomes continue to coil, the chromosomes are shortened and thickened to a more visible state.
Prophase – The replicated chromosomes condense into compact rods. Each rod Each rod consists of two sister chromatids joined at the centromere or the chromosome.
☆ These questions asked the reader to describe and draw the cell when it was in the telophase and the late prophase stages of mitosis. ☆ During meiotic prophase in females, chromosomes condense and pair to

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Retrieved Text: The first draft of the human genome sequence was reported a year ago. It may be a good time to remind ourselves that the genetic information encoded in the ∼3000-Mb sequence is stored not only in the public or private databases but also in the tiny space of the cell nucleus. The total length of human genomic DNA, which resides in 23 chromosomes, reaches approximately one meter. It is by no means a simple task to fold up the long DNA molecules and package them within a cell nucleus whose diameter is only ∼10 μm. Even more striking is that the DNA molecules are faithfully duplicated and segregated into two daughter cells in an extremely limited space. Although more than 100 years have passed since Walther Flemming first described the dynamic behavior of chromosomes (or mitosis) during cell division, it remains highly mysterious how this remarkable process of chromosome segregation is achieved at a mechanistic level. From a cytological point of view, two dramatic events occur on chromosomes during mitosis. The first one is the conversion of an amorphous mass of interphase chromatin into a discrete set of rod-shaped chromosomes (chromosome condensation), which occurs from prophase to metaphase (Koshland and Strunnikov 1996; Hirano 2000). The second is the splitting of chromosomes into two halves, which takes place highly synchronously at the onset of anaphase (Dej and Orr-Weaver 2000; Nasmyth et al. 2000). As a crucial prerequisite for these events, duplicated chromosomes (sister chromatids) must be held together immediately after DNA replication in S phase and throughout

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Retrieved Text: Within 24 hours, a human cell can divide into two daughter cells that are identical to the original. This cell cycle includes growth of the cell, duplication of the DNA and division of the chromosomes and cell contents. The stages of the cycle -- which occur in both plants and animals -- are called interphase, mitosis and cytokinesis. Kinetochore and nonkinetochore -- also known as interpolar -- microtubules play an important role in the separation of chromosomes and the formation of daughter cells. These microscopic structures are both made from subunits called tubulin, but they have different functions during cell division.
When a cell enters mitosis, a microtubule-based structure called a spindle forms with two poles at either end of the enlarged cell. The chromosomes align along the center of the spindle prior to separation of the chromatids -- half of the duplicated chromosomes. Kinetochore microtubules extend from the spindle poles toward the center of the cell and attach to the chromatids at a structure called the kinetochore. The nonkinetochore microtubules also extend from the spindle toward the center of the cell, but they do not attach to the chromatids. Instead they overlap at the center of the spindle.
During late prophase -- one of the phases of mitosis -- the plate-like kinetochore forms on the duplicated chromosomes. Each chromosome has two kinetochores -- one for each identical sister chromatid -- attached to kinetochore microtubules from opposite poles. Kinetochore microtubules attached to the kinetochore cause the chromosomes to line up along the middle of the spindle. Nonkinetochore microtubules

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Retrieved Text: Following DNA replication, sister chromatids must stay connected for the remainder of the cell cycle in order to ensure accurate segregation in the subsequent cell division. This important function involves an evolutionarily conserved protein complex known as cohesin; any loss of cohesin causes premature sister chromatid separation in mitosis. Here, we examined the role of cohesin in sister chromatid cohesion prior to mitosis, using fluorescence in situ hybridization (FISH) to assay the alignment of sister chromatids in interphase Drosophila cells. Surprisingly, we found that sister chromatid cohesion can be maintained in G2 with little to no cohesin. This capacity to maintain cohesion is widespread in Drosophila, unlike in other systems where a reduced dependence on cohesin for sister chromatid segregation has been observed only at specific chromosomal regions, such as the rDNA locus in budding yeast. Additionally, we show that condensin II antagonizes the alignment of sister chromatids in interphase, supporting a model wherein cohesin and condensin II oppose each other’s functions in the alignment of sister chromatids. Finally, because the maternal and paternal homologs are paired in the somatic cells of Drosophila, and because condensin II has been shown to antagonize this pairing, we consider the possibility that condensin II-regulated mechanisms for aligning homologous chromosomes may also contribute to sister chromatid cohesion.
As cells grow, they replicate their DNA to give rise to two copies of each chromosome, known as sister chromatids, which separate from each other once the cell divides. To ensure that sister chromatids end up in different daughter cells, they are kept together

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Retrieved Text: Hey guys, I was just wondering does interphase double the chrosome number from 46 to 92 due to DNA replication?
Is meiosis part of the cell cycle?
HELP - Mitosis and Meiosis???
It doesn't double the chromosome number, but it doubles the amount of DNA. Chromosomes usually look like chromatids, but because you only see them in prophase, you see them with twice the amount of DNA. There are the same number of chromosomes, as the number of centromeres does not increase.
But how can it go from 46 to 46 to 23? How can it divide in way that maintains the same no. of chromosomes after a division into 2 cells?
It contains 46 chromosomes. It divides to give 23 chromosomes in meiosis 1. This then divides again to give 23 chromosomes.
The original DNA has been replicated before division. The reason you think a chromosome lookes like and "X" rather than an "l" is because you only see them during mitosis when they are dividing.
But they are still called a single chromosome, because a) the two strands are exactly the same and b) they are attached to a single centromere.
So it starts with 46, then divides to give 2 cells of 23 each, then those divide to give 4 cells of 23?
the cell goes through normal interphase and chromosones are copied and are visible as sister chromoatids.
chromotids are seperated in meiosis 2.
so to answer your question it goes 2N -> 2N -> N -> N because after interpahse the chromosones are sister chromatids (the have replicated) but they are still

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Retrieved Text: The process of meiosis creates 4 haploid gamete cells from a diploid cell. In animals these gametes are called eggs and sperm and in plants they are called eggs and pollen. For meiosis to occur it must go through two divisions, Meiosis I and Meiosis II. During Meiosis, the cell goes through the same stages as Mitosis (Interphase, Prophase, Metaphase, Anaphase, and Telophase/Cytokinesis), but it goes through these phases twice, but with some minor differences.
Creates 4 haploid gamete cells from a diploid cell.
At this point the DNA is in its chromatin form and the DNA replicates.
Homologous Chromosomes (matching chromosomes from mom and dad) join up together and exchange share genetic information. Happens during Prophase I of meiosis.
Matching chromosomes from mother and father. They are the same size, shape and carry genes for the same traits.
The chromosomes line up down the middle along with their homologous pair.
The homologous chromosomes pull apart from one another and move toward opposite poles.
Chromosomes are now at separate poles, nuclear membranes start to form around the 2 sets of chromosomes, and the chromosomes start to unwind back into chromatin. Cytokinesis occurs and the two cells split. These two cells are haploid at this point since each cell contains only 1 of each homologous pair. The next 4 phases occur to each of these cells.
Notice that we skip interphase this time around because there is no replication of DNA between Meiosis I and Meiosis II.
At this point the chromosomes reorganize and the nuclear membranes start to dissolve again. Sister chromatids are joined by

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Retrieved Text: Which cartoon shows the correct way for the chromosomes to line up at the metaphase plate during mitosis?
What would happen if one chromosome failed to have microtubules from both poles attach?
One daughter cell would not have a copy of that chromosome.
Diatoms are protists that have rigid glass walls. Based on this you can conclude that they carry out cytokinesis similarly to ______________.
What would happen if a cell were unable to properly condense its chromosomes during prophase?
The chromosomal DNA would be subjected to shearing forces, fragmenting the chromosome.
What would happen if cytokinesis occurred before telophase was completed?
A cell that has just exited the G1 phase of the cell cycle (and will eventually go on to divide) will next enter ___________________.
Chromosomes condense and begin to be visible during _____________.
A number of chemical treatments cause microtubules to fall apart. Colchicine (mitonic inhibitor) is one such drug. What would happen if a dividing cell was treated with colchicine?
What would happen to a cell if it went directly from prophase to anaphase (i.e., it failed to undergo metaphase)?
The daughter cells would probably not get equal numbers of chromosomes.
A chimpanzee bone marrow cell, in prophase of mitosis, contains 48 chromosomes. How many chromatids does it contain?
When do homologous chromosomes pair?
Starting with one cell, how many daughter cells will be formed when meiosis is complete?
Sperm cells and ova can be classified as ______________ cells.
How many pairs of homologous chromosomes are found in human males?
The cellular process by which gametes are formed from specialized nonreproductive cells is ________ .
Crossing over occurs during which stage

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Retrieved Text: The Cell Cycle & Mitosis. Chapter 5. 5.1 – The Cell Cycle. Key Concept: Cells have distinct phases of growth, reproduction, and normal functions. When a living thing grows, what happens to its cells?.
Cells have distinct phases of growth, reproduction, and normal functions.
When a living thing grows, what happens to its cells?
Does an animal get larger because each cell increases in size or because it produces more of them?
What are some things that all cells in your body must have?
The cell cycle has 4 main stages.
The cell cycle is a regular pattern of growth, DNA replication, and cell division.
The main stages of the cell cycle are: Gap 1, Synthesis, Gap 2, & Mitosis.
Mitosis occurs only if the cell is large enough and the DNA undamaged.
Cells divide at different rates.
The rate of cell division varies with the need for that type of cell.
Cell volume increases faster than surface area.
Cells need to stay small to allow diffusion and osmosis to work efficiently.
Surface area must allow for adequate exchange of materials.
Cells divide during mitosis and cytokinesisinto two new daughter cells.
Chromosomes condense at the start of mitosis.
Chromosomes: carry genetic information (DNA) that is passed from one generation of cells to the next.
DNA wraps around proteins (histones) that condense it.
DNA plus proteins (histones) is called chromatin.
Sister chromatids are held together at the centromere.
Mitosis and cytokinesis produce two genetically identical daughter cells.
Interphase prepares the cell to divide.
Chromosomes condense, spindle fibers form, and the nuclear membrane disappears.
Mitosis divides the cell’s nucleus in four phases.
Chromosomes line up across the middle of the cell.
Sister chromatids

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Retrieved Text: Chromosome*s contain the long strands of DNA* that carry genetic information. They are the unit of DNA replication in living cells. Typical prokaryotic cells contain a single circular chromosome. Eukaryotic cells, with their much larger genomes, have multiple, linear chromosomes. The length and linear nature of eukaryotic chromosomes increases the challenge of keeping the genetic material organized and of passing the proper amount of DNA to each daughter cell during mitosis.
During cell division, eukaryotic chromosomes condense into highly coiled 4 armed structures. The tight coiling and high degree of organization in this supercoiled DNA facilitates proper segregation during mitosis and cell division. The following illustration explores the structure, classification and features of a eukaryotic chromosome.
The earliest efforts to describe chromosomes were based on visible characteristics. The most obvious features are the centromere* which is the central constriction point and the branches stemming from this constriction point. These branches are called arms. Each chromosome has either two or four arms extending from the centromere.
Late in the cell cycle when the process of mitosis has begun but before the cell has divided, cells contain two complete copies of their genome. When the DNA is supercoiled in preparation for cell division, the pair of copies of each chromosome come together to form the characteristic x-shaped structure. The point of attachment of the two complete copies occurs at the centromere. Each copy of the chromosome is called a chromatid*. The two copies of each chromosome are called sister chromatids. When cells divide, one sister chromatid is delivered to each of

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Retrieved Text: NCERT Solutions for Class 11 Biology Chapter 10 Cell Cycle and Cell Division free download in PDF for or to Study online without downloading files. Download Solutions of other subjects and study notes related to all chapters.
Specialised kind of cell division that reduces the chromosomes number by half, hence it is called reductional division.
Occurs during gametogenesis in plants and animals.
Involves two sequential cycles of nuclear and cell division called Meiosis I and Meiosis II.
It results in 4 haploid daughter cells.
Interphase occurs prior to meiosis which is similar to interphase of mitosis except the S phase is prolonged.
Format ion of gametes: In sexually reproducing organisms.
Genetic variability: Variations are very important for evolution.
Maintenance of chromosomal number: By reducing the chromosome number in gametes. Chromosomal number is restored by fertilisation of gametes.
Since the number of chromosomes in the parent and progeny cells is the same, it is called as equational division. Mitosis is divided into four sub stages.
Replicated chromosomes, each consisting of 2 chromatids, condense and become visible.
Microtubules are assembled into mitotic spindle.
Nucleolus and nuclear envelope disappear.
Centriole moves to opposite poles.
Spindle fibres attached to kinetochores (small disc-shaped structures at the surface of centromere) of chromosomes.
Chromosomes line up at the equator of the spindle to form metaphase plate.
Centromeres split and chromatids separate.
Chromatids move to opposite poles due to shortening of spindal fibres.
Chromosomes cluster at opposite poles.
Nuclear envelope assembles around chromosomes clusters’.
Nucleolus, Golgi Complex, E.R. reforms.
Maintenance of surface/volume ratio. Maintain Nucleo-cytoplasmic ratio.
Reproduction in unicellular organisms, lower plants and some insects.
Vegetative reproduction in plants takes place by mitosis.

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Retrieved Text: 0:15Skip to 0 minutes and 15 secondsWelcome to the next video for 'Cancer in the 21st century; The Genomic Revolution'. Previously we've looked at cells, their components, and how they work and are controlled by genes under normal conditions. So we can now move on to thinking about how cells grow and divide and how these processes are normally regulated, before we begin to consider how these processes are interrupted in cancer cells. So what is the cell cycle? In most eukaryotic cells there is a series of events which must occur in a particular order which ultimately results in the cell's division and duplication or replication.
0:58Skip to 0 minutes and 58 secondsThe phases or steps in the cycle are controlled by checkpoints, which prevent the cell cycle progressing to subsequent stages until all the necessary molecular events have occurred. Cells begin the cycle by entering interphase. Interphase is where the cell prepares for division by growing and duplicating it's DNA. Interphase can be further broken down into three discrete phases-- G1, S, and G2. In G1, normal cellular functions occur, as well as cell growth where organelle and cytoskeletal components increase. S is the synthesis stage. Nuclear DNA replicates producing two identical copies of each chromosome. During the G2 phase, the cell continues to grow and prepare for mitosis and cell division.
1:58Skip to 1 minute and 58 secondsMitosis-- or the M-phase-- can be further subdivided into prophase, metaphase, anaphase, and telophase. During prophase, the chromosomes become visible and condense. Each identical copy of a single

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Retrieved Text: Meiosis is the process by which gametes are made. In this process, we begin with a 4n cell (double the normal amount of DNA), and we will end up with 4 non-identical haploid (n) daughter gametes, after 2 divisions. There are 6 stages within each of the divisions; Prophase, Prometaphase, Metaphase, Anaphase, Telophase and Cytokinesis. In this article, we will look at all the stages of meiosis in addition to its significance in diseases.
Firstly the nuclear envelope disintegrates and the chromosomes begin to condense. Spindle fibres appear which will be important for successful division of the chromosomes.
Now the spindle fibres attach to the chromosomes at a points along the chromosomes called centromeres. While this is happening the chromosomes continue to condense.
Fig 2 – Image of prometaphase I.
Next, homologous (Maternal and Paternal versions of the same chromosome) chromosomes align along the equator of the cell and a process called random assortment occurs here – this is when maternal and paternal chromosomes line up randomly align themselves on either side of the equator, this leads to genetic diversity among offspring.
To further increase the genetic diversity, homologous chromosomes exchange parts of themselves such that one chromosome contains both maternal and paternal DNA. This process is known as crossing over, and the points at which this occurs on a chromosome are refund to as chiasmata.
Here each of the homologous chromosomes get pulled towards opposite poles of the cell as the spindle fibres retract to divide the DNA between the two cells which will be formed.
Fig 4 – Image of Anaphase

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Retrieved Text: The stage in mitosis and in the second meiotic division when the centromere splits and the chromatids separate and move to opposite poles.
The stage of the first meiotic division when the two halves of a bivalent chromosome separate and move to opposite poles.
With respect to the results listed in Table 2, the orange and grape juices of the five food companies, at both exposure times considered, induced significant formation of mitotic spindle changes, represented in this study by colchicine metaphase and anaphase and telophase bridges, proving to be genotoxic, and chromosome breaks, characterized by the formation of micronuclei.
To determine if aurora A kinase (AAK) plays a post-metaphase role in Drosophila S2 cell division, AAK was knocked down by RNA interference (RNAi), and microtubule (MT) intensity in the spindle midzone during late anaphase was quantified (Fig.
1 (b) IVM, in vitro maturation; GVBD, germinal vesicle breakdown; MI, Metaphase 1; AI, Anaphase 1; TI, TelophaseI; MII, MetaphaseII; SEM, standard error of the mean.
The damaged chromosomes, in the form of acentric chromatids or chromosome fragments, lag behind in anaphase when centric elements move towards the spindle poles.
Several chromosomal aberrations (CA's) like chromosomal break, stickiness, laggard, and multipolar anaphase have been formed.
It delivers the two groups of chromosomes to positions adjacent to the polar furrows midway between pairs of plastids in anaphase and a phragmoplast is constructed in the midzone (Fig.
10 and 50 [micro]g/ml number of prophases and telophases generally increases by prolonging treatments, and the number of metaphases and anaphases decreases.
This can be seen from the simulation results in To

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Retrieved Text: The physical location of a gene on a chromosome is called its locus.
arrangement of p g pairs of chromosomes. The diagram below g shows four possible arrangements of chromosomes during metaphase 1 from an individual that has 6 total chromosomes. chromosomes Suppose that the pink chromosomes are those that the individual inherited from its mother and the blue colored ones were inherited from its father. For each chromosome pair, the chromosome that is on the left (maternal or paternal) is determined randomly. As can be , g p seen, there are several alignment possibilities.
Can you tell the stage of cells Can o (image in the right hand) What do the different colors represent for?
chromosomes, four per set. In the h f t I th following diagram, what phase of mitosis, meiosis I or meiosis II, is this cell in?
The cell is in metaphase of meiosis II. You can tell because the chromosomes are lined up along the metaphase plate, and it plate has only four pairs of sister chromatids. If it were mitosis, the cell would have eight pairs of ll ld h i ht i f sister chromatids.
A cell is diploid and contains three chromosomes per set. Draw the arrangement g of chromosomes during metaphase of mitosis, and metaphase I and II of meiosis.
1. Division of intracellular organelles 2. Cell cycle control 3. Mechanics of cell division 4..

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Retrieved Text: Research in my lab focuses on the molecular genetics of meiosis in Drosophila melanogaster.
Chromosomes are dynamic elements that exist within a nuclear ecosystem. This ecosystem can respond to developmental and environmental cues by changing the chromatin state, the 3-dimensional chromosome architecture, and chromosome movement during cell division. My research focuses on the highly regulated processes that are implemented during meiosis that ensure homologous chromosomes segregate before sister chromatids. Crossovers, which provide the connections between chromosomes that guarantee accurate segregation, are formed by using homologous recombination to repair programed double-stranded breaks in the DNA. There are more breaks than crossovers, however, and only a subset of breaks are selected to become crossovers. Only crossovers made in specific parts of the chromosome are useful for chromosome segregation, and thus the decision about which breaks to repair as crossovers is critical and highly regulated. My research combines traditional Drosophila genetics and modern whole genome sequencing approaches to ask how chromosomes integrate a complex set of input requirements to select which breaks are repaired as crossovers.

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Retrieved Text: Q.7:- Describe the following: (a) synapsis (b) bivalent (c) chiasmata Draw a diagram to illustrate your answer.
(a) Synapsis: During zygotene of prophase I stage homologou s chromosomes start pairing together and this process of association is called synapsis. Electron micrographs of this stage indicate that chromosome synapsis is accompanied by the formation of complex structure called synaptonemal complex.
(b) Bivalent: The complex formed by a pair of synapsed homologous chromosomes is called a bivalent or a tetrad i.e., 4 chromatids or a pair of chromosomes.
(c) Chiasmata: The beginning of diplotene is recognized by the dissolution of the synaptonemal complex and the tendency of the synapsed homologous chromosomes of the bivalents to separate from each other except at the sites of crossovers. These points of attachment (X-shaped structures) between the homologous chromosomes are called chiasmata.

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Retrieved Text: Reciprocal exchange between homologs, in combination with sister chromatid cohesion, promotes proper segregation of homologs at Meiosis I. Missegregation of chromosomes during meiosis causes abnormal chromosome numbers in gametes. Errors in meiotic chromosome segregation can lead to infertility and, in humans, are responsible for genetic disorders like Trisomy 21.	Meiotic recombination is initiated by double-strand breaks (DSBs). Repair of these breaks is biased to occur by invasion of homologs, not sister chromatids. This bias is mediated both by a meiosis-specific recombinase, Dmc1 and by the suppression of Rad51/Rad54 mediated recombination between sister chromatids. In dmc1 mutants, DSBs fail to get repaired, triggering a recombination checkpoint resulting in a prophase arrest. Mek1, a meiosis-specific kinase activated by DSBs, is required to prevent DSB repair using sister chromatids.	To confirm that inactivation of Mek1 promotes intersister repair, two-dimensional gel analysis was used to look at intersister and interhomolog joint molecules (JMs). Inactivation of a conditional allele of Mek1 in a dmc1 background resulted exclusively in intersister JMs. To determine whether MEK1 suppression of intersister repair requires the presence of homologs, DSB repair was analyzed in haploid strains containing mek1 and dmc1. The finding that dmc1 haploids have unrepaired breaks that are repaired in the absence of MEK1 demonstrates that the mechanism by which MEK1 suppresses intersister repair is specific to sister chromatids. Interestingly, repair in wild-type haploids is either delayed or absent. Comparing DSB repair at different hotspots in disomic haploid and haploid strains, I found that DSBs are repaired only on the disomic chromosomes, indicating that repair on different

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Retrieved Text: This article is about the cellular structure. For other uses, see Spindle (disambiguation).
In cell biology, the spindle apparatus (or mitotic spindle) refers to the cytoskeletal structure of eukaryotic cells that forms during cell division to separate sister chromatids between daughter cells. It is referred to as the mitotic spindle during mitosis, a process that produces genetically identical daughter cells, or the meiotic spindle during meiosis, a process that produces gametes with half the number of chromosomes of the parent cell.
Besides chromosomes, the spindle apparatus is composed of hundreds of proteins. Microtubules comprise the most abundant components of the machinery.
This diagram depicts the organization of a typical mitotic spindle found in animal cells. Chromosomes are attached to kinetochore microtubules via a multiprotein complex called the kinetochore. Polar microtubules interdigitate at the spindle midzone and push the spindle poles apart via motor proteins. Astral microtubules anchor the spindle poles to the cell membrane. Microtubule polymerization is nucleated at the microtubule organizing center.
Attachment of microtubules to chromosomes is mediated by kinetochores, which actively monitor spindle formation and prevent premature anaphase onset. Microtubule polymerization and depolymerization dynamic drive chromosome congression. Depolymerization of microtubules generates tension at kinetochores; bipolar attachment of sister kinetochores to microtubules emanating from opposite cell poles couples opposing tension forces, aligning chromosomes at the cell equator and poising them for segregation to daughter cells. Once every chromosome is bi-oriented, anaphase commences and cohesin, which couples sister chromatids, is severed, permitting the transit of the sister chromatids to opposite poles.
The cellular spindle apparatus includes the spindle microtubules, associated

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Retrieved Text: Delay in G2 – a rescue compartment?
Can giant cells repair DNA?
Mitotic death is a delayed response of p53 mutant tumours that are resistant to genotoxic damage. Questions surround why this response is so delayed and how its mechanisms serve a survival function. After uncoupling apoptosis from G1 and S phase arrests and adapting these checkpoints, p53 mutated tumour cells arrive at the G2 compartment where decisions regarding survival and death are made. Missed or insufficient DNA repair in G1 and S phases after severe genotoxic damage results in cells arriving in G2 with an accumulation of point mutations and chromosome breaks. Double strand breaks can be repaired by homologous recombination during G2 arrest. However, cells with excessive chromosome lesions either directly bypass the G2/M checkpoint, starting endocycles from G2 arrest, or are subsequently detected by the spindle checkpoint and present with the features of mitotic death. These complex features include apoptosis from metaphase and mitosis restitution, the latter of which can also facilitate transient endocycles, producing endopolyploid cells. The ability of cells to initiate endocycles during G2 arrest and mitosis restitution most likely reflects their similar molecular environments, with down-regulated mitosis promoting factor activity. Resulting endocycling cells have the ability to repair damaged DNA, and although mostly reproductively dead, in some cases give rise to mitotic progeny. We conclude that the features of mitotic death do not simply represent aberrations of dying cells but are indicative of a switch to amitotic modes of cell survival that may provide additional mechanisms of genotoxic resistance.
Following severe genotoxic damage,

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Retrieved Text: Results demonstrate that chromosome behavior in meiosis is independently influenced by the kinetochore associated Monopolin protein that mediates monopolar attachement and Rec8, which is involved in maintaining cohesion between sister centromeres in Saccharomyces cerevisiae.
Studies have identified a protein required for cohesion but is not a Cohesin subunit. This protein, Eco1p(Ctf7), was found during experiments searching for mutants that generate separate sister centromeres. While Eco1p(Ctf7) is needed for cohesion establishment during DNA replication, it is not required for cohesion maintenance during the G2 and M phases.
A study has been conducted to investigate the behavior of two cohesin subunits known to important for sister chromatid cohesion processes during mitosis and meiosis. Findings indicate that Scc1p is expressed at extremely low levels in meiotic cells, while the scc1-73 allele, considered to be conditionally lethal in mitosis, exerts a modest influence on spore formation and viability. A meiotic cohesin that binds sister chromatids together is also required for repair of strand exchange between homologs.
Abstracts: Golgi membranes are absorbed into and reemerge from the ER during mitosis. The debate about transport in the Golgi - two sides of the same coin?

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Retrieved Text: The epitope recognized by ab992 maps to a region between residue 575 and the C-terminus (residue 631) human Rad21 homolog using the numbering given in entry NP_006256.1 (GeneID 5885).
Synthetic peptide (Human) conjugated to KLH - which represented a portion of human Rad21 encoded within exon 14 (LocusLink ID 5885).
HeLa cell lysate. FFPE human breast fibroadenoma tissue sections.
Our Abpromise guarantee covers the use of ab992 in the following tested applications.
Used at a dilution of 1/200 for 30 min incubation (see Abreview for further information).
WB 1/500 - 1/5000. Predicted molecular weight: 72 kDa.
Band observed at ~130 kDa.
Cleavable component of the cohesin complex, involved in chromosome cohesion during cell cycle, in DNA repair, and in apoptosis. The cohesin complex is required for the cohesion of sister chromatids after DNA replication. The cohesin complex apparently forms a large proteinaceous ring within which sister chromatids can be trapped. At metaphase-anaphase transition, this protein is cleaved by separase/ESPL1 and dissociates from chromatin, allowing sister chromatids to segregate. The cohesin complex may also play a role in spindle pole assembly during mitosis. Also plays a role in apoptosis, via its cleavage by caspase-3/CASP3 or caspase-7/CASP7 during early steps of apoptosis: the C-terminal 64 kDa cleavage product may act as a nuclear signal to initiate cytoplasmic events involved in the apoptotic pathway.
Belongs to the rad21 family.
The C-terminal part associates with the head of SMC1A, while the N-terminal part binds to the head of SMC3.
Cleaved by separase/ESPL1 at the onset of anaphase. Cleaved by caspase-3 and caspase-7 at the beginning of apoptosis. The cleavage by

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Retrieved Text: mutation in the promoter region. in the 5' untranslated region. changes how the gene is expressed.
the exons in the two genes are swapped between genes. can result in new genes. Mechanism for the evolution of new genes. in the process, coding sequences from different genes are brought together to generate a protein with a novel combination of domains.
transposons (mobile genetic elements) moves from places of DNA with no function into genes with a function.
gene from one organism moves to another organism. bacterial mechanism. exchange of genetic information. Process by which DNA is passed from the genome of one organism to that of another, even to an individual from another species. This contrasts with vertical gene transfer of genetic information from parent to progeny.
cells whose genes are passed onto offspring. mutations in germ cells are passed from generation to generation. Cell type in a diploid organism that carries only one set of chromosomes and is specialized for sexual reproduction. Sperm/egg/gamete.
mutations are not passed to offspring. any cell that forms part of the body of a plant or animal that is not a germ cell or germ-line precursor.
caused by failures of normal mechanisms for copying and repairing DNA. can change the regulation of a gene. affects individual nucleotides in a sequence.
transposons/retrotransposons. encode the components needed for movement. contain multiple elements. can move gene elements between genes if excised improperly. Short segment of DNA that can move, sometimes through an RNA intermediate, from one location in a genome to another; an important source of genetic variation in most genomes.
a

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Retrieved Text: What are centromeres composed of?
The chromosome structure is similar in most cases to an X, but the location of the point where the two arms of the X touch may vary. This contact point has a name, of course (a biologist never misses a chance to name something): the centromere.
Without centromeres, cells cannot divide properly and mitosis fails.
Centromeres are actually defined by specific regions of DNA called alpha satellite, which specifically bind centromere proteins.
Scientists have identified over 20 that contribute to forming the centromere complex.
Without them, kinetochores do not have a place to attach to pull the sister chromatids apart.
Why is mitosis necessary for living organisms?
How do cytokinesis and telophase differ?
How do chromosomes divide during anaphase?
How can mitosis be a form of asexual reproduction?
How does mitosis conserve the chromosome number?
How are mitosis and meiosis different?
What are kinetochores made of?

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Retrieved Text: Deposition Author(s): Brautigam, C.A., Chaudhary, J., Yu, H.
Mitotic centromeric targeting of HP1 and its binding to Sgo1 are dispensable for sister-chromatid cohesion in human cells.
Kang, J., Chaudhary, J., Dong, H., Kim, S., Brautigam, C.A., Yu, H.
Human Shugoshin 1 (Sgo1) protects centromeric sister-chromatid cohesion during prophase and prevents premature sister-chromatid separation. Heterochromatin protein 1 (HP1) has been proposed to protect centromeric sister-chromatid cohesion by directly targeting Sgo1 to centromeres in mitosis. Here we show that HP1α is targeted to mitotic centromeres by INCENP, a subunit of the chromosome passenger complex (CPC). Biochemical and structural studies show that both HP1-INCENP and HP1-Sgo1 interactions require the binding of the HP1 chromo shadow domain to PXVXL/I motifs in INCENP or Sgo1, suggesting that the INCENP-bound, centromeric HP1α is incapable of recruiting Sgo1. Consistently, a Sgo1 mutant deficient in HP1 binding is functional in centromeric cohesion protection and localizes normally to centromeres in mitosis. By contrast, INCENP or Sgo1 mutants deficient in HP1 binding fail to localize to centromeres in interphase. Therefore, our results suggest that HP1 binding by INCENP or Sgo1 is dispensable for centromeric cohesion protection during mitosis of human cells, but might regulate yet uncharacterized interphase functions of CPC or Sgo1 at the centromeres.
Department of Pharmacology, Howard Hughes Medical Institute, USA.

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Retrieved Text: Spatial regulation of the spindle assembly checkpoint and anaphase-promoting complex in Aspergillus nidulans.
The spindle assembly checkpoint (SAC) plays a critical role in preventing mitotic errors by inhibiting anaphase until all kinetochores are correctly attached to spindle microtubules. In spite of the economic and medical importance of filamentous fungi, relatively little is known about the behavior of SAC proteins in these organisms. In our efforts to understand the role of gamma-tubulin in cell cycle regulation, we have created functional fluorescent protein fusions of four SAC proteins in Aspergillus nidulans, the homologs of Mad2, Mps1, Bub1/BubR1 and Bub3. Time-lapse imaging reveals that SAC proteins are in distinct compartments of the cell until early mitosis when they co-localize at the spindle pole body. SAC activity is, thus, spatially regulated in A. nidulans. Likewise, Cdc20, an activator of the anaphase-promoting complex/cyclosome, is excluded from interphase nuclei, but enters nuclei at mitotic onset and accumulates to a higher level in mitotic nuclei than in the surrounding nucleoplasm before leaving in anaphase/telophase. The activity of this critical cell cycle regulatory complex is likely regulated by the location of Cdc20. Finally, the gamma-tubulin mutation mipAD159 causes a nuclear-specific failure of nuclear localization of Mps1 and Bub1/R1 but not of Cdc20, Bub3 or Mad2.
Chromosome segregation in budding yeast: sister chromatid cohesion and related mechanisms.
Studies on budding yeast have exposed the highly conserved mechanisms by which duplicated chromosomes are evenly distributed to daughter cells at the metaphase-anaphase transition. The establishment of proteinaceous bridges between sister chromatids, a function provided by a ring-shaped complex known as

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Retrieved Text: In cell division, the mitotic spindle self-assembles from nucleated microtubules and dynamic instability is used to find and capture chromosomes.
The basic mechanisms of spindle formation can be studied from first principles using simulations and in vitro work.
Cells typically have several degenerate mechanisms, including microtubule tension and spindle elongation, for achieving anaphase, where chromosomes are pulled apart into two identical sets.
This final lecture of the molecular machines topic is about the machinery of mitosis, the division of one cell into two identical daughter cells (Slide 1). The lecture builds on material presented in the previous lecture (‘Cellular machinery’) and describes how the mechanisms of mitosis are studied using simulations and in vitro.
The process of mitosis is divided into several descriptive stages, which are in general the same across different species and different cells. These are summarised in Slide 2.
Mitosis begins with prophase, where the nuclear DNA condenses from an essentially random polymer into distinct chromosomes. The DNA has been duplicated prior to cell division so there are two copies – so-called sister chromatids which are held together at a point known as the centromere. Microtubules nucleate at two centrosomes located on the outside of the nucleus. The polymerisation of overlapping microtubules between the centrosomes pushes them apart to form the mitotic spindle.
In prometaphase, the nuclear membrane disintegrates and microtubules emanating from the spindle poles attach to the centromere of each chromosome. For correct division, each chromosome requires one sister chromatid to be attached to each spindle pole. The resultant of the pulling forces from each pole causes

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Retrieved Text: GO:0000403 Y-form DNA binding Interacting selectively and non-covalently with segment of DNA shaped like a Y. This shape occurs when DNA contains a region of paired double-stranded DNA on one end and a region of unpaired DNA strands on the opposite end.
GO:0019237 centromeric DNA binding Interacting selectively and non-covalently with a centromere, a region of chromosome where the spindle fibers attach during mitosis and meiosis.
GO:0032181 dinucleotide repeat insertion binding Interacting selectively and non-covalently with double-stranded DNA containing a dinucleotide repeat insertion or a deletion resulting in unpaired dinucleotide repeats.
GO:0000406 double-strand/single-strand DNA junction binding Interacting selectively and non-covalently with a region of DNA that contains double-stranded DNA flanked by a region of single-stranded DNA.
GO:0000400 four-way junction DNA binding Interacting selectively and non-covalently with DNA containing four-way junctions, also known as Holliday junctions, a structure where two DNA double strands are held together by reciprocal exchange of two of the four strands, one strand each from the two original helices.
GO:0032137 guanine/thymine mispair binding Interacting selectively and non-covalently with double-stranded DNA containing a G/T mispair.
GO:0000404 heteroduplex DNA loop binding Interacting selectively and non-covalently with DNA containing a loop. A loop occurs when DNA contains a large insertion or deletion that causes a region of unpaired single-stranded DNA to loop out, while the rest of the DNA is in a paired double-stranded configuration.
GO:0030983 mismatched DNA binding Interacting selectively and non-covalently with double-stranded DNA containing one or more mismatches.
GO:0032357 oxidized purine DNA binding Interacting selectively and non-covalently with oxidized purine residues in DNA.
GO:0032142 single guanine insertion binding Interacting selectively and non-covalently

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Input Text: Answer the following question given this paragraph: 

A general plant life cycle is represented by the diagram in Figure below . From the figure, you can see that the diploid sporophyte has a structure called a sporangium (plural, sporangia) that undergoes meiosis to form haploid spores. A spore develops into a haploid gametophyte. The gametophyte has male or female reproductive organs that undergo mitosis to form haploid gametes (sperm or eggs). Fertilization of gametes produces a diploid zygote. The zygote grows and develops into a mature sporophyte, and the cycle repeats.


Q: What is the structure in a diploid sporophyte that undergoes meiosis to form haploid spores?

 Choices:

- dikaryotic

- hymenium

- sporangium

- hyphae

A:

Target Text: sporangium

#### Retrieved Documents ####

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Retrieved Text: Young to old. A life cycle?
Not in the biological sense. Life cycles describe the amount of DNA present at a specific stage or time in the life of an organism. Is there a haploid or diploid amount of DNA? That is the key question.
Sexual reproduction occurs in a cycle. Diploid parents produce haploid gametes that unite and develop into diploid adults, which repeat the cycle. This series of life stages and events that a sexually reproducing organism goes through is called its life cycle. Sexually reproducing organisms can have different types of life cycles. Three are represented in Figure below and described following sections.
Life cycles can vary in sexually reproducing organisms. Three types of sexual life cycles are shown here. Do you see how they differ? The letter n indicates haploid stages of the life cycles, and 2n indicates diploid stages.
The haploid life cycle is the simplest life cycle. It is found in many single-celled eukaryotic organisms. Organisms with a haploid life cycle spend the majority of their lives as haploid gametes. When the haploid gametes fuse, they form a diploid zygote. It quickly undergoes meiosis to produce more haploid gametes that repeat the life cycle.
Plants, algae, and some protists have a life cycle that alternates between diploid and haploid phases, known as alternation of generations. In plants, the life cycle alternates between the diploid sporophyte and haploid gametophyte. Spore forming cells in the diploid sporophyte undergo meiosis to produce spores, a haploid reproductive cell. Spores can develop into an adult without fusing with another cell.

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Retrieved Text: Like all plants Toxicodendron diversilobum exhibits an alternation of generations. This means that during the life cycle of the plant it alternates between a multicellular diploid sporophyte generation and a multicellular haploid gametophyte generation. Since the Pacific poison oak is in the phylum Angiosperm it has a dominant sporophyte generation which means that the gametophyte generation will be more dependent on the sporophyte generation.
The first part of the angiosperm life cycle takes place in the flower of the plant. Here in the anther the microsporocytes develop and undergo meiosis which produces haploid microspores. Each microspore undergoes one division of mitosis to form a generative cell and a tube cell. Together they form an immature pollen grain. The generative cells then go through a second mitotic division which produces two sperm nuclei. Inside the ovule one megaspore undergoes meiosis to form four haploid megaspore. Three die off and one remains. The remaining megaspore undergoes three mitotic divisions and generates an 8 nucleate embryo sac also known as a megagametophyte.
Next pollination occurs. The pollen grain germinates on the stigma where a pollen tube grows down into the style. Eventually it grows down into the ovary through the micropyle. One sperm nucleus then fuses with the egg which creates a diploid zygote, and the other sperm fuses with the central cell of the egg to form the endospore.
Now that the embryo has formed it grows inside the embryo sac. The ovule creates a protective seed coat around the embryo and embryo sac. Then the seed is dropped from fruit

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Retrieved Text: Download "Rhizarians. Forams. Radiolarians. Cercozoans"
14 Figure 29.3 Exploring Derived Traits of Plants Charophyte algae lack the key traits of plants described in this figure: alternation of generations; multicellular, dependent embryos; walled spores produced in sporangia; multicellular gametangia; and apical meristems. This suggests that these traits were absent in the ancestor common to plants and charophytes but instead evolved as derived traits of plants. Not every plant exhibits all of these traits; certain lineages of plants have lost some traits over time. Alternation of Generations The life cycles of all plants alternate between two generations of distinct multicellular organisms: gametophytes and sporophytes. As shown in the diagram below (using a fern as an example), each generation gives rise to the other, a process that is called alternation of generations. This type of reproductive cycle evolved in various groups of algae but does not occur in the charophytes, the algae most closely related to plants. Take care not to confuse the alternation of generations in plants with the haploid and diploid stages in the life cycles of other sexually reproducing organisms (see Figure 13.6). Alternation of generations is distinguished by the fact that the life cycle Mitosis n Alternation of generations: five generalized steps 5 The spores develop into multicellular haploid gametophytes. n MEIOSIS 1 The gametophyte produces haploid gametes by mitosis. Gametophyte (n) Spore includes both multicellular haploid organisms and multicellular diploid organisms. The multicellular haploid gametophyte ( gamete-producing plant ) is named for its production by mitosis of haploid gametes eggs and sperm that fuse during

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Retrieved Text: Polypodium is a perennial herb. It is found mostly in temperate regions. It has worldwide distribution. Mostly is attached to some rocks. But some forms are epiphytic.
The plant body is sporophyte. Plant body is divided into rhizome. leaves and roots.
It forms the main stem of the plant. Rhizome is rounded, underground. But its apex is erect. It has very few blanches. It is covered with persistant leaf bases and hairs.
The leaves are pinnately compound or simple. In compound leaf, the leaf has leaflets or pinnae. Leaves are lobed frond like. They have long stalked petiole. The leaves are arranged spirally. The form simple reticulate or dichotomous venation. The young leaves show circinate vernation.
They have adventitious roots. These roots arise from the lower surface of rhizome.
In cross section rhizome is composed of epidermis, cortex and stele. Epidermis is outer most covering. It is without stomata. Cortex is wide and it is composed of parenchymatous tissues. Canal are absent in it. Stele is present in the inner side. It is covered by endodermis and pericycle. Polypodium has polystelic protostele. Each protostele has concentric vascular bundles. The xylem are exarch (protoxylem lies on the periphery of metaxylem).
Leaflets or lamina of leaf is covered by upper and lower epidermis. Epidermis has a layer of cutin. Lower epidermis has stomata. Mesophyll tissues are present between two epidermises. Mesophyll tissues are differentiated into palisade and spongy mesophyll. The leaf has collateral and concentric vascular bundles.
Root has simple internal structure. It has outer epidermis, cortex and stele. Stele is protostcle and diarch.
Some leaves

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Retrieved Text: This biphasic life cycle that plants demonstrate is referred to as an?
The life cycle of a plant from?
The leafy green gametophyte is the haploid generation that produces sperm and eggs. The sperm must swim through a film of water to the egg. The zygote develops into a stalked, diploid sporophyte that emerges from the gametophyte plant. The sporophyte is topped by a brown capsule in which haploid spores are produced by meiosis. These are dispersed and germinate, producing another green gametophyte generation.
What is the function and structure of the flower?
Flowers are the part of the sporophyte generation in flowering plants that is dedicated to sexual reproduction.
Insect and vertebrate pollination is ____ efficient than wind pollination.
that put more efforts into mechanisms to attract the animals (i.e. nectar, odoriferous compounds, appearance and etc.) ensured the success of those flowering plant lineages.
Stamens and carpels are composed of two to three distinctly different parts.
1.) To recap pollination is when a pollen grain lands on the stigma of a flower's carpel.
2.) The pollen generates a tube to transfer the sperm from the male gametophyte to the female gametophyte.
3.) In flowering plants we see a double fertilization from the fusion of the sperm to specific cells of female gametophyte.
4.) This double fertilization gives rise to a zygote and endosperm.
5.) When the female gametophyte develops in the manner previously illustrated (polygonum type), which is the most common, the double fertilization gives rise to a (2n) zygote and a (3n) endosperm.
How do seeds germinate and grow?
Seeds need moisture and warmth to germinate. If conditions

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Retrieved Text: Plants are multicellular organisms in the kingdom Plantae that use photosynthesis to make their own food. There are over 300,000 species of plants; common examples of plants include grasses, trees, and shrubs. Plants have an important role in the world’s ecosystems. They produce most of the world’s oxygen, and are important in the food chain, as many organisms eat plants or eat organisms which eat plants. The study of plants is called botany.
Plants are autotrophs; they produce their own food. They do so via photosynthesis, which is the process of making nutrients such as sugars from light energy and carbon dioxide. Photosynthesis occurs in cell organelles called chloroplasts, which contain chlorophyll and carotenoids, molecules that absorb light energy and change it into a usable form. Heterotrophs, on the other hand, are organisms that cannot make their own food and must eat other organisms to survive. Many heterotrophs eat plants. Other heterotrophs eat animals that have eaten plants. Plants are primary producers in many ecosystems, giving them a vital role in the survival of many other organisms. In addition, oxygen is a byproduct of photosynthesis, and many organisms depend on oxygen to survive. We couldn’t live without plants.
Plants are multicellular organisms with eukaryotic cells. A eukaryotic cell is a relatively large cell with a true nucleus and other organelles that perform specific functions. Plants, protists, fungi, and animals all have eukaryotic cells. Plant cells are distinguished by their cell walls containing cellulose, chloroplasts that perform photosynthesis, and a large central vacuole that holds water and keeps the

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Retrieved Text: die „Reduktionsteilung“ beginnt im Diplonten mit einer eigenartigen Zelle [...], deren Nachkommen, die „Haploten“ [...] auf die ursprüngliche Chromosomenzahl herabgesetzt sind, und wiederum ein einfaches Lebewesen, den „Haplonten“ [...] durch neue Zellenteilungen erzeugen.
From this organism [the haplont] arise the gametes by ordinary mitosis; and by their union is produced the zygote from which arises a diploid, asexual spore-producing diplont (in plants the sporophyte), thus completing the life-cycle.
1: The diploid stage of a life cycle; diplophase, 2: An organism having a life cycle in which the direct products of meiosis act as gametes; only the gametes of diplonts are haploid; cf. haplont.

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Retrieved Text: I noticed some patches of a small, bright-green plant fully submerged in the slack waters beside the River Ehen a kilometre or so below the outflow from Ennerdale Water. My first look suggested a tangle of narrow, flaccid grass-like stems but a closer examination showed that each of the narrow stems had whorls of branches arising from them at intervals (similar to the pattern seen in horsetails). Their size and structure suggested an affinity to the vascular plants such as Myriophyllum and Juncus that I also saw in the river that day but, actually, these plants belong to an algal genus called Nitella. I could not see any reproductive organs on these plants, but other evidence points to them being Nitella flexilis.
Nitella belongs to a group of algae called the Charophytes which have been the subject of vigorous debate by phycologists and evoloutionary scientists for a long time. The author of one recent paper went so far as to claim that “no group in the plant kingdom has presented greater difficulties in classification …”. They are usually placed in the green algae (Chlorophyta) although some people regard them as a separate division entirely. Charophytes, in fact, have several characteristics, as well as their size and pigmentation, that suggest that they may be the closest algal relatives of land plants. These similarities extend to the reproductive organs (see Chris Carter’s image of Chara virgata in a post from July last year).
Nitella flexilis photographed in the River Ehen, 18 March 2014. Scale bar: 1 centimetre.
Under the microscope, some

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Retrieved Text: Algaes are difficult to define. Some classify the group as all eukaryotic photosynthesizing microorganisms. This definition includes the Euglenoid and Dinoflagellates groups, both of which are known to be more closely related to other groups of non-photosynthesizing protozoa than to other algae. For this reason, those two groups are sometimes classified as protozoa rather than algae. In this discussion, we will group euglenoids and dinoflagellates with the algae so that we may compare their photosynthetic characteristics. Keep in mind that this inclusion does not imply close relation to other algae.
Another difficulty in classifying algae is determining whether they are protists, plants, or whether they merit their own kingdom. Different classification systems answer this question in different ways, with some even splitting the group between the kingdoms Protista and Plantae. Here we have grouped algae with protozoa and slime molds in Protista because mthe majority of algae are unicellular, and even the multicellular algae are structurally simple compared to true plants.
Within the classification of algae, individual species are divided into five groups, based on characteristics such as type of chlorophyll molecule used in photosynthesis and type of reproductive cycle. The structure of the chloroplast is also used, for a very important reason. According to the endosymbiotic theory of chloroplast evolution, proposed by Lynn Margulis of the University of Massachusetts, Amherst, chloroplasts may have evolved when small photosynthesizing cells were engulfed, but not digested, by larger cells. Instead, the two types of cells developed a symbiotic relationship, with the photoautotroph living inside the larger cell. The number of

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Retrieved Text: The embryo sac is also known as the female gametophyte or megagametophyte. In the angiosperm the ovule contains a reduced sac like structure known as the embryo sac which is embedded in the sporophytic tissue.
Any plant has two components a gametophyte (haploid) and a sporophyte (diploid).As we move from lower plants like bryophytes ,where main plant body is gametophyte and sporophyte is dependant on gametophyte , to higher plants like angiosperms where main plant body is sporophyte and gametophyte(pollen grain in male flower and embryo sac in female flower) is dependant on the sporophyte ;that is the whole plant ,the size of gametophyte gets reduced and the gametophyte becomes dependant on the sporophyte.thus the embryo sac(present in female flower ) which is haploid is called as female gametophye.
In pines the female gametophyte contains?

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Retrieved Text: When one walks through a contemporary forest, all of the surrounding trees are vascular plants. Wood, which is made up primarily of xylem , and bark, which contains phloem , are the major structural elements of the trunks and stems. These trees produce seeds, whether they be formed within the cones of the pines or within fruits, such as the winged samaras of maples or the fleshy cherries of the cherry tree. In the Carboniferous period a similar hike would also place one in a forest of woody trees, many as large as 98 feet (30 meters) tall, but there would be no seeds produced. These plants were seedless vascular plants, which were propogated by spores. Ultimately they became extinct, leaving behind expansive fossil fuel deposits.
The differences between spores and seeds are extensive. Seeds are multicellular structures that provide a protected place where the egg (n) was to be fertilized by male gamete nuclei (n) in pollen. The resulting cell, called a zygote , is diploid (2n), the same as the original plant that produced it. It repeatedly divides mitotically, while still within the protection of the seed coat, to form an embryo. The embryo may remain dormant for a significant time period but ultimately emerges from the seed when it germinates.
The seedless vascular plants do not have this protection. Their gametes are produced mitotically by a gametophyte (n) that lives independently. There are often many vase-shaped archegonia on these small plants, and the unfertilized egg is inside the base of this structure. The embryo formed

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Retrieved Text: This set contains 67 questions on plant reproduction, anatomy and physiology as well as plant evolution.
A) formation of motile male gametes.
B) alternation of sporophyte and gametophyte generations.
C) presence of both haploid and diploid stages.
Which of the following is NOT a characteristic of plants?
A) Glucose is made from photosynthesis.
B) Cell walls contain cellulose.
D) Diploid and haploid generations alternate in their life cycle.
E) Diploid and haploid phases of their life cycle produce spores.
Cactus plants are adapted to the hot and dry deserts of North and South America. Which of the following characteristics would NOT help cacti to survive the extreme heat and low rainfall?
A) A thick, waxy cuticle.
B) A stem with a small surface area.
C) Stomata that are closed during the day.
D) Thin leaves with a large surface area.
Transport of the products of photosynthesis is understood to occur by pressure flow through the phloem from a source (such as the leaves where the products are produced) to a sink (such as a developing fruit where they are used or stored). Which of the following statements about this transport is FALSE?
A) Water enters the phloem by osmosis.
B) Phloem tubes in a source have a low water pressure.
C) Water and sugar move through the phloem tubes because of pressure.
D) Sugar is removed from phloem by active transport in the sink area.
E) Solutes are pushed along by the flow of water in the phloem.

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Retrieved Text: Bryophytes are the group of plants that are the closest extant relative of early terrestrial plants. The first bryophytes (liverworts) most likely appeared in the Ordovician period, about 450 million years ago. Because of the lack of lignin and other resistant structures, the likelihood of bryophytes forming fossils is rather small. Some spores protected by sporopollenin have survived and are attributed to early bryophytes. By the Silurian period, however, vascular plants had spread through the continents. This compelling fact is used as evidence that non-vascular plants must have preceded the Silurian period.
More than 25,000 species of bryophytes thrive in mostly damp habitats, although some live in deserts. They constitute the major flora of inhospitable environments like the tundra, where their small size and tolerance to desiccation offer distinct advantages. They generally lack lignin and do not have actual tracheids (xylem cells specialized for water conduction). Rather, water and nutrients circulate inside specialized conducting cells. Although the term non-tracheophyte is more accurate, bryophytes are commonly called nonvascular plants.
In a bryophyte, all the conspicuous vegetative organs—including the photosynthetic leaf-like structures, the thallus, stem, and the rhizoid that anchors the plant to its substrate—belong to the haploid organism or gametophyte. The sporophyte is barely noticeable. The gametes formed by bryophytes swim with a flagellum, as do gametes in a few of the tracheophytes. The sporangium—the multicellular sexual reproductive structure—is present in bryophytes and absent in the majority of algae. The bryophyte embryo also remains attached to the parent plant, which protects and nourishes it. This is a characteristic of

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Retrieved Text: The process of meiosis creates 4 haploid gamete cells from a diploid cell. In animals these gametes are called eggs and sperm and in plants they are called eggs and pollen. For meiosis to occur it must go through two divisions, Meiosis I and Meiosis II. During Meiosis, the cell goes through the same stages as Mitosis (Interphase, Prophase, Metaphase, Anaphase, and Telophase/Cytokinesis), but it goes through these phases twice, but with some minor differences.
Creates 4 haploid gamete cells from a diploid cell.
At this point the DNA is in its chromatin form and the DNA replicates.
Homologous Chromosomes (matching chromosomes from mom and dad) join up together and exchange share genetic information. Happens during Prophase I of meiosis.
Matching chromosomes from mother and father. They are the same size, shape and carry genes for the same traits.
The chromosomes line up down the middle along with their homologous pair.
The homologous chromosomes pull apart from one another and move toward opposite poles.
Chromosomes are now at separate poles, nuclear membranes start to form around the 2 sets of chromosomes, and the chromosomes start to unwind back into chromatin. Cytokinesis occurs and the two cells split. These two cells are haploid at this point since each cell contains only 1 of each homologous pair. The next 4 phases occur to each of these cells.
Notice that we skip interphase this time around because there is no replication of DNA between Meiosis I and Meiosis II.
At this point the chromosomes reorganize and the nuclear membranes start to dissolve again. Sister chromatids are joined by

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Retrieved Text: Meiotic chromosome segregation in triploid strains of Saccharomyces cerevisiae.
Meiosis in triploids results in four highly aneuploid gametes because six copies of each homolog must be segregated into four meiotic products. Using DNA microarrays and other physical approaches, we examined meiotic chromosome segregation in triploid strains of Saccharomyces cerevisiae. In most tetrads with four viable spores, two of the spores had two copies of a given homolog and two spores had only one copy. Chromosomes segregated randomly into viable spores without preferences for generating near haploid or near diploid spores. Using single-nucleotide polymorphisms, we showed that, in most tetrads, all three pairs of homologs recombined. Strains derived from some of the aneuploid spore colonies had very high frequencies of mitotic chromosome loss, resulting in genetically diverse populations of cells.

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Retrieved Text: Angiosperm life cycle comprises of two generations, the Sporophytic and the Gametophytic. These two generations alternate with each other in regular sequence. This phenomenon is known as Alternation of Generation.
The angiospermic plant, that is usually differentiated into roots, stems, leaves and flowers, is the Sporophyte as it consists of diploid cells (2n). It is the dominant phase of the angiosperm life cycle. As a result of reduction division, it produces haploid Microspores and Megaspores. The Gametophytic phase (n) is represented by two structures, the Male Gametophyte and the Female Gametophyte. The male gametophyte is represented by the microspores (pollen grains) and the pollen tube with two sperm nuclei and a tube nucleus. The female gametophyte is generally, represented by eight-nucleate embryo sac. Both gametophytes are highly reduced and completely dependent on the sporophyte.
The reduction division occurs at the time of formation of microspores and megaspores and the diploid number is restored when zygote is formed. The zygote, therefore is the first cell of the sporophyte.
Another significant point is the formation of Endosperm. Endosperm in angiosperms is usually triploid as it develops from Primary Endosperm Nucleus formed as a result of the union of two polar nuclei and one sperm nucleus. It is thus formed after the process of fertilization.
During the course of evolution there has been gradual reduction and loss of independence in gametophytic generation whereas sporophytic generation has registered a gradual increase in size to attain even tree like proportions in angiosperms.
The oospore (thick-walled zygote) produces Embryo by segmentation; the ovule produces Seed and the

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Retrieved Text: Sporangia are the specialized spore producing structures found in plants. In Pteridophytes, two types of sporangia are present. The two types of sporangia are (1) Eusporangium and (2) Leptosporangium. This classification is proposed by Goebel in 1881 based on the developmental pattern of sporangia. The spores produced in the Eusporangium are called eusporangiospores and those produced in the Leptosporangium are called leptosporangiospores.
Eusporangium: The sporangium develops from a GROUP of INITIAL cells and such a development is called development.
Leptosporangium: The sporangium develops from a SINGLE INITIAL cell and such a development is called Leptosporangiate development.
The present post describes the Similarities and Differences between a Eusporangium and Leptosporangium.
Ø Both Eusporangia and Leptosporangia are the spore producing structures in vascular plants.
Ø Both are formed on the sporophyll (a specialized leaf) of the diploid sporophytic plant.
Ø Both produce haploid spores after meiosis.
Ø The first division of the initials of both sporangia is periclinal (transverse division).
1 Eusporangium is developed from a group of initial cells. Leptosporangium is developed from a single initial cell.
2 Sporangial initial undergo a periclinal division to form an outer layer and an inner layer of cells. Sporangial initial undergo a periclinal division to form an outer cell and inner cell.
3 The outer layer of cells produces the sporangial wall. The entire components of the sporangium such as stack, sporangial wall, and sporogenous tissue are produced only from the outer cell.
4 The inner layer of cells produces the spore mother cell, which latter undergo meiosis to produce haploid spores. Inner cell does not have any role in the

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Retrieved Text: In this internet lesson, you will review the steps of meiosis and view video simulations of this type of cell division. You will also view an onion root tip and calculate the percentage of cells at each of the stages of cell division.
1. Give an example of asexual reproduction.
2. What is a clone?
3. (Click the next button) What is the difference between haploid and diploid?
4. What is the diploid chromosome number for humans?
13. Name 2 errors that can occur during meiosis.
Test Yourself - Try some of the problem sets on the test yourself pages.

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Retrieved Text: Plants Transpiration involves losing water vapor from aerial parts of plants. Diploid and Haploid Cells Diploid and haploid cells are involved in sexual reproduction of higher eukaryotic organisms. Forests with numerous tree species, and therefore a mix of water-management strategies, appear more tolerant of drought. Ecological Isolation Explained With Examples What is ecological isolation and how does it prevent the occurrence of inter-species hybrids? Natural and artificial selection forms the basis of evolution on this planet. The two stages of meiosis are meiosis I and meiosis. In the 1940s and 1950s, studies regarding genes and DNA progressed to the discovery of the double helical DNA structure. Framing Guide for Article Summaries - how to write a summary for any article. As a result, it makes sweet hot topic birmingham things taste a lot less sweet. Buzzle explains what is a missense mutation and also explains certain examples of disorders that it may cause.
This post explains the basic difference between the two. Mimic each other as a protective measure. Mullerian Mimicry Müllerian mimicry is a survival technique wherein two species that are equally noxious.
Articles in Easy Understandable English for Learners.Articles about biology and biological sciences written by scientists and researchers internationally.
Which will tell you how the cellular life on planet Earth is classified. Read on to know the details. What is a Gene Pool, refer to the following article, this post explains this type of mutation in a comprehensive manner. Refers to the reappearance of an ancestral trait in an individual. When discussing chemosynthesis, and Brown University

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Retrieved Text: Which cartoon shows the correct way for the chromosomes to line up at the metaphase plate during mitosis?
What would happen if one chromosome failed to have microtubules from both poles attach?
One daughter cell would not have a copy of that chromosome.
Diatoms are protists that have rigid glass walls. Based on this you can conclude that they carry out cytokinesis similarly to ______________.
What would happen if a cell were unable to properly condense its chromosomes during prophase?
The chromosomal DNA would be subjected to shearing forces, fragmenting the chromosome.
What would happen if cytokinesis occurred before telophase was completed?
A cell that has just exited the G1 phase of the cell cycle (and will eventually go on to divide) will next enter ___________________.
Chromosomes condense and begin to be visible during _____________.
A number of chemical treatments cause microtubules to fall apart. Colchicine (mitonic inhibitor) is one such drug. What would happen if a dividing cell was treated with colchicine?
What would happen to a cell if it went directly from prophase to anaphase (i.e., it failed to undergo metaphase)?
The daughter cells would probably not get equal numbers of chromosomes.
A chimpanzee bone marrow cell, in prophase of mitosis, contains 48 chromosomes. How many chromatids does it contain?
When do homologous chromosomes pair?
Starting with one cell, how many daughter cells will be formed when meiosis is complete?
Sperm cells and ova can be classified as ______________ cells.
How many pairs of homologous chromosomes are found in human males?
The cellular process by which gametes are formed from specialized nonreproductive cells is ________ .
Crossing over occurs during which stage

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Retrieved Text: Lulú. “El GIF De La Semana: Mitosis En Tiempo Real.” Esceptica, 22 Jan. 2014, esceptica.org/2014/01/19/el-gif-de-la-semana-mitosis-en-tiempo-real/.
Mitosis and Meiosis sound very similar, but while they share some similar concepts they are two different biological terms. What is Mitosis? Mitosis is cell division creating two “daughter” cells. Daughter cells have the same number of chromosomes and the same kind of chromosomes as the parent cell. What is Meiosis? Meiosis is creating four “daughter” cells that have half of the chromosomes as the parent cell.
While Mitosis and Meiosis both create daughter cells they make two different kinds. Mitosis creates diploid cells or cells that have 23 chromosomes. While meiosis makes haploid cells or gametes which are your reproductive cells such as sperm in males and eggs in females.
Mitosis exists in six different stages each stage doing something different inside of the cell undergoing mitosis.
Interphase: This stage is when the cell is only preparing for Mitosis or Meiosis(Interphase happens in both). This is also where a cell spends most of its life.
Prophase: Prophase is the “first” stage where the nuclear membrane and the nucleus disappear, chromosomes condense and the mitotic spindles form.
Metaphase: This stage is when the duplicated chromosomes line up at the center of the cell. Fun fact this is called the metaphase plate.
Anaphase: Anaphase is when the duplicated chromosomes separate into two identical groups and move towards opposite ends of the cell.
Telophase: This is the second to last stage where membranes form around the two groups of chromosomes at different ends to produce the nuclei in the daughter cells.

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Retrieved Text: Haploid is the term used when a cell has half the usual number of chromosomes. A normal eukaryote organism is composed of diploid cells, one set of chromosomes from each parent. However, after meiosis, the number of chromosomes in gametes is halved. That is the haploid condition.
In humans, the diploid number of chromosomes is 46 (2x23). The number in haploid cells (sperm and eggs) is 23. Some types of animals are haploid, such as male Hymenoptera (ants, bees and wasps). This is a special genetic system called haplodiploidy.
Some plants and animals are polyploid, with more than two sets of chromosomes. For example, one species of wheat is hexaploid, with six sets of chromosomes, although other species of wheat have only two sets. Because so many organisms are diploid, it can become confusing whether haploid refers to one set of chromosomes or more than one. The special term monoploid can be used; it means one set of chromosomes.
Haploid Facts for Kids. Kiddle Encyclopedia.

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Retrieved Text: Gametogenesis is the process whereby a haploid cell (n) is formed from a diploid cell (2n) through meiosis and cell differentiation. Gametogenesis in the male is known as spermatogenesis and produces spermatozoa. Gametogenesis in the female is known as oogenesis and result in the formation of ova. In this article we shall look at both spermatogenesis and oogenesis.
Males start producing sperm when they reach puberty, which is usually from 10-16 years old. Sperm are produced in large quantities (~200 million a day) to maximise the likelihood of sperm reaching the egg. Sperm are continually produced as males need to be ready to utilise the small window of fertility of the female.
Sperm production occurs in the testes of the male, specifically in the seminiferous tubules. The tubules are kept separate from the systemic circulation by the blood-testis barrier.
The blood-testis barrier is formed by Sertoli cells and is important in preventing hormones and constituents of the systemic circulation from affecting the developing sperm, and also in preventing the immune system of the male from recognising the sperm as foreign – as the sperm are genetically different from the male and will express different surface antigens. Sertoli cells also have a role in supporting the developing spermatozoa.
Spermatogonia are the initial pool of diploid cell that divide by mitosis to give two identical cells. One of these cells will be used to replenish the pool of spermatogonia – these cells are A1 spermatogonia. This replenishment of spermatogonia means that males are fertile throughout their adult life. The other cell –

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Retrieved Text: How do you know what type of organism this chromosome sample came from?
It is a human because it is diploid with two copies of 23 chromosomes. It is not a human because it is quadroploid with 46 chromosomes.
It is a human because it is haploid with 23 chromosomes. It is not a human because it is diploid with two copies of 23 chromosomes.
1. Is this cell diploid? Why?
Yes it is diploid. It is a regular body cell, and they are all diploid.
Yes it is diploid. It is a reproductive cell, and they are all diploid.
No it is not diploid. It is a reproductive cell, and they are all haploid.
No it is not diploid. It is a regular body cell, and they are all haploid.
2. Do regular body cells (not sperm and egg) become specialized as different types of cells because the amount of DNA that is in them changes?
No, they have the same amount of DNA and are different because different parts of the DNA are expressed.
Yes, they go through a process called mitosis that changes the amount of DNA present in the cell.
Yes, they have different amounts of DNA because different amounts of DNA are expressed.
No, they have the same amount of DNA because they go through a process called meiosis that keeps the same amount of DNA in the cell.
Using their knowledge of diploid cells, students answer science questions in this quiz/worksheet combo. Practice questions assess your understanding of different terms, such as mutations and DNA.

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Retrieved Text: Gametes are specialised haploid cells that are used to combine and when they do they combine to form a new diploid cell. That process of combination is called fertilization.
Now, you are hopefully familiar with sperm and egg, the two most common kinds of gametes that you've heard of. Where sperm they're small specialized for quick delivery of the DNA to the other cell, the other kind of gamete which is called the egg. Eggs are large. Why are they so large? It allows them to accumulate or store up large amounts of resources to provide for their newly developed diploid cell which will eventually become some new offspring like you and I became came from a single fertalized egg.
We take a look over here we can see in this scale, this thing that looks almost like a planet, that's the egg and you can see how much larger the egg is in size comparison to the sperm. Now if they were both the same size, they would be called isogametes.
We take a look at an isogamete. Every isogamete looks like the other. Now how are iso- how are sperm and egg made different? That happens during the process of either spermatogenesis or oogenesis.
Here we see a generic description of meiosis. The process of making gametes where here we have a cell that has let's suppose four chromosomes. Ultimately it can create four haploid cells. So this is a diploid cell. See it has pairs of homologous chromosomes. These are individual haploid cells, no more do they

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Retrieved Text: Rescan, Lenormand and Roze (2016) recently published new models on the evolution of life cycles in The American Naturalist.
Most animals and protists have diploid life cycles in which the haploid stage is reduced to a single-celled gamete.
Other organisms, such as charophytes and dinoflagellates, have a haploid life cycle in which the diploid phase is reduced to the zygote and meiosis occurs before any mitotic development.
There’s a third type of life cycle, that regular TME readers may have stumbled across with my posts: haploid-diploidy in which somatic development occurs in both haploid and diploid stages. In seed plants, the haploid stage is rather limited, but in fungi, mosses and macroalgae, the haploid stage is much more important.
[Due to the difference in duration of one phase and the corresponding limits to selection], the problem of the evolution of life cycles (i.e., the relative degrees of development of the haploid and diploid phases) is often recast in terms of the opportunity of selection within each phase.
One model suggests diploids may benefit from the masking of deleterious mutations. But, this assumes deleterious mutations have the same effect in both haploids and homozygous diploids. Recent transcriptomic studies in haploid-diploid species, such as Coelho et al. (2007), have demonstrated some genes are only expressed in one policy and mutations in these genes would have no effect in the other stage as they are not expressed.
Moreover, these genetic models cannot explain the evolutionary stability of haploid-diploid life cycles without considering additional mechanisms, such as ecological niche differentiation (Hughes and Otto 1999).
the interplay between

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Retrieved Text: Meiosis is a reduction division involving one diploid parent cell dividing to produce four haploid daughter cells, i.e. each daughter cell has half the number of chromosomes of the parent cell.
Meiosis then consists of two cell divisions, known as meiosis I and meiosis II. In the first division, which consists of different phases, the duplicated DNA is separated into daughter cells . In the next division, which immediately follows the first, the two alleles of each gene are separated into individual cells.
about the process of meiosis that requires both an understanding of meiosis, and also of how pop beads are used in lab to represent chromosomes in the various stages of meiosis.

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Retrieved Text: Reciprocal exchange between homologs, in combination with sister chromatid cohesion, promotes proper segregation of homologs at Meiosis I. Missegregation of chromosomes during meiosis causes abnormal chromosome numbers in gametes. Errors in meiotic chromosome segregation can lead to infertility and, in humans, are responsible for genetic disorders like Trisomy 21.	Meiotic recombination is initiated by double-strand breaks (DSBs). Repair of these breaks is biased to occur by invasion of homologs, not sister chromatids. This bias is mediated both by a meiosis-specific recombinase, Dmc1 and by the suppression of Rad51/Rad54 mediated recombination between sister chromatids. In dmc1 mutants, DSBs fail to get repaired, triggering a recombination checkpoint resulting in a prophase arrest. Mek1, a meiosis-specific kinase activated by DSBs, is required to prevent DSB repair using sister chromatids.	To confirm that inactivation of Mek1 promotes intersister repair, two-dimensional gel analysis was used to look at intersister and interhomolog joint molecules (JMs). Inactivation of a conditional allele of Mek1 in a dmc1 background resulted exclusively in intersister JMs. To determine whether MEK1 suppression of intersister repair requires the presence of homologs, DSB repair was analyzed in haploid strains containing mek1 and dmc1. The finding that dmc1 haploids have unrepaired breaks that are repaired in the absence of MEK1 demonstrates that the mechanism by which MEK1 suppresses intersister repair is specific to sister chromatids. Interestingly, repair in wild-type haploids is either delayed or absent. Comparing DSB repair at different hotspots in disomic haploid and haploid strains, I found that DSBs are repaired only on the disomic chromosomes, indicating that repair on different

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Retrieved Text: A cell or nucleus that may participate in sexual fusion to form a *zygote. It is normally haploid and thus on fusion of two gametes a diploid zygote is formed. In virtually all plants (exceptions are those with a *diplontic life cycle ) meiosis is separated from *gametogenesis by the development of a somatic gametophyte generation (see alternation of generations ). In the primitive algae and fungi the gametes are often naked and *isogamous. In more advanced forms there is a trend through *anisogamy to *oogamy and specialization of the gametes, so that they become better protected and less dependent on water for survival and dispersal. See also sexual reproduction.

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Retrieved Text: A spermatocyte is a male gametocyte which is derived from a spermatogonium. Initially, a spermatogonium divides by mitosis into two so-called primary spermatocytes. A primary spermatocyte is also diploid, and, in turn, gives place by meiosis to two secondary spermatocytes, which this time are haploid.

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Input Text: Answer the following question given this paragraph: 

The only difference between each nucleotide is the identity of the base. There are only four possible bases that make up each DNA nucleotide: adenine (A), guanine (G), thymine (T), and cytosine (C).


Q: There are only four possible bases that make up each dna nucleotide: adenine, guanine, thymine, and?

 Choices:

- phenylalanine

- guarine

- cytosine

- taurine

A:

Target Text: cytosine

#### Retrieved Documents ####

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Retrieved Text: What Causes the Double Helix to Twist in a DNA Picture?
Deoxyribonucleic acid is present in the nucleus of every cell in our body in compactly folded up forms called chromosomes. The four building blocks that make up the DNA are repeated to form a long chain. They encode a vast amount of information, ranging from eye color to the predisposition to a disease.
Nucleotides are the subunits of DNA. The four nucleotides are adenine, cytosine, guanine and thymine. Each of the four bases has three components, a phosphate group, a deoxyribose sugar and a nitrogen-containing base. The nitrogenous base attached to the bases may be a double-ringed purine or a single-ringed pyrimidine. Adenine and guanine are purine bases, while cytosine and thymine are pyrimidine bases. These four nucleotides, referred to as the A, C, G and T are the building blocks of DNA.
The four nucleotides join with each other and form what is famously known as the DNA ladder. Hydrogen bonds form only between a purine and a pyrimidine nucleotide base, so the adenine always binds to thymine and cytosine to guanine to form a long chain. Further linking on the DNA ladder occurs by the bonding of the sugar of one nucleotide to the sugar of the adjoining nucleotide by a phosphate group. The sugar phosphate bonding forms the sides of the DNA ladder and is responsible for the twist in DNA.
The Human Genome Project determined the sequence of the three billion bases present in human DNA. The arrangement of these bases encode for the 20,000

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Retrieved Text: DNA is a nucleic acid. Nucleic acids are biological macromolecules containing oxygen, hydrogen, carbon, nitrogen and phosphorus. There are two types of nucleic acids: ribonucleic acid (RNA) and deoxyribonucleic acid (DNA). Nucleic acids are made up of basic units called nucleotides, which bind together with covalent bonds to form a polynucleotide or the nucleic acid.
A nucleotide is made up of three parts: a five-carbon sugar (deoxyribose in the case of nucleotides in DNA), a phosphate group connected with a covalent bond to the sugar’s fifth carbon atom, and one of four possible nitrogen-containing bases connected with a covalent bond to the sugar’s first carbon atom. The nitrogen base may be one of the single-ring pyrimidine derivatives thymine (T) or cytosine (C), or one of the double ring purine derivatives adenine (A) or guanine (G).
When the nucleotides are linked together in a strand of DNA, the phosphate group attached to the 5′ (pronounced ‘five prime’) carbon of the deoxyribose sugar of one nucleotide becomes joined to the 3′ carbon on the sugar of an adjacent nucleotide. The strand in which the sugar alternates with phosphate is called a sugar-phosphate backbone. The backbone is not symmetrical. It has a definite orientation, with a free 3` hydroxyl group at one end and a free 5` phosphate group at the other end. The purine and pyrimidine bases stick out to one side of the sugar-phosphate backbone.
In each DNA molecule, the number of nucleotides containing adenine (A) equals the number containing thymine (T), and the number containing guanine (G) equals the

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Retrieved Text: Deoxyribonucleic acid (DNA) is the basic hereditary material found in the nucleus of most cells. This genetic information is passed on from one generation to the next and is required for protein synthesis. This important life information is packaged in the nucleus in a highly structured and organised manner. DNA is tightly wrapped around proteins called histones and this complex structure is the nucleosome. Nucleosomes are the structural and functional units of a chromatin. These are then folded and looped over other proteins and this chromatin is further compressed into the chromatid of a chromosome.
DNA is a linear polymer that is made up of nucleotide units. The nucleotide unit consists of a base, a deoxyribose sugar, and a phosphate. There are four types of bases: adenine (A), thymine (T), guanine (G), and cytosine (C). Each base is connected to a sugar via a ß glycosyl linkage. The nucleotide units are connected via the O3' and O5' atoms forming phosphodiester linkages.In normal DNA, the bases form pairs: A to T and G to C. This is called complementarity. A duplex of DNA is formed by two complementary chains that are arranged in an anti-parallel manner.
NDB ID: BD0002 Throughtout the site, in all DNA nucleotide block models, adenine is red, thymine is blue, cytosine is yellow, guanine is green.
DNA can have several conformations. The most common one is called B-DNA. B-DNA is a right-handed double helix with a wide and narrow groove. The bases are perpendicular to the helix axis. DNA can also be found in the A

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Retrieved Text: A cell’s hereditary information is encoded in chromosomes in the cell’s nucleus. Each chromosome is composed of proteins and deoxyribonucleic acid (DNA). The chromosomes contain smaller hereditary units called genes, which are relatively short segments of DNA. The hereditary information is expressed or used through the synthesis of ribonucleic acid (RNA). Both nucleic acids—DNA and RNA—are polymers composed of monomers known as nucleotides, which in turn consist of phosphoric acid (H3PO4), a nitrogenous base, and a pentose sugar.
The two types of nitrogenous bases most important in nucleic acids are purines—adenine (A) and guanine (G)—and pyrimidines—cytosine (C), thymine (T), and uracil (U). DNA contains the nitrogenous bases adenine, cytosine, guanine, and thymine, while the bases in RNA are adenine, cytosine, guanine, and uracil. The sugar in the nucleotides of RNA is ribose; the one in DNA is 2-deoxyribose. The sequence of nucleotides in a nucleic acid defines the primary structure of the molecule.
RNA is a single-chain nucleic acid, whereas DNA possesses two nucleic-acid chains intertwined in a secondary structure called a double helix. The sugar-phosphate backbone forms the outside the double helix, with the purine and pyrimidine bases tucked inside. Hydrogen bonding between complementary bases holds the two strands of the double helix together; A always pairs with T and C always pairs with G.
Cell growth requires replication, or reproduction of the cell’s DNA. The double helix unwinds, and hydrogen bonding between complementary bases breaks so that there are two single strands of DNA, and each strand is a template for the synthesis of a new strand.

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Retrieved Text: Nucleotides are the basic structural units of nucleic acids, which control the production of proteins in living organisms. The nucleotides are made up of a phosphate group, a pentose sugar, and a nitrogen base.
This shows the basic structure of a nucleotide. This example has the sugar ribose, and is characteristic of RNA. The nucleotide could contain the sugar deoxyribose, characteristic of DNA. For DNA, the bases may be adenine, guanine, cytosine or thymine. For RNA the bases are adenine, guanine, cytosine and uracil.

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Retrieved Text: DNA stands for Deoxyribo nucleic Acid , it was discovered by Frederic Maischer.
DNA is a double stranded molecule made up of elongated chain of sub-units called nucleotides.
DNA is mainly found in nucleus and in small amount it is also found in mitochondria an chloroplast.
Chemically a nucleotide has three components.
Nitrogenous base are of two type i.e.Purine & Pyrimidines.
Purines contain two nitrogen base i.e. Adinine and Guanine.
Pyrimidine nitrogen base are Thymine and Cytosine, thus there are four kinds of nucleotide present in DNA i.e. Adinine, Guanine, Thymine, Cytosine.
DNA molecule is consists of two polynucleotide strand, forming a double helix structure.
Each strand has a backbone of sugar and phosphate, nitrogen base is attached to the sugar.
Two strands are joined together by hydrogen bonds between the bases.
Adenine pairs with thymine whereas guanine pairs with cytosine.
Adenine and thymine are complementary to each other and cytosine is complementary to guanine.
DNA is genetic material and contains genetic information in coded form.
DNA has two main function replication and expression.
RNA is single stranded nucleic acid made up of phosphate, ribose sugar and nitrogen base uracil, adinine, guanine and cytosine.
It is found in nucleus as well as cytoplasm.
Its main function is to synthesis the protein.
RNA is of three kind.
1.Messenger RNA (mRNA): It brings the massage from DNA found in the nucleus to cytoplasm in the coded form.
2.Ribosomal RNA (rRNA): Present in ribosome which is the site of protein synthesis.
3.Transfer RNA (t RNA): It is the carrier of amino acid and transfers it to the ribosome.
Virus was discovered by Russian Scientist Iavanosky during the test of Mosaic

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Retrieved Text: "ACGT" redirects here. For the Japanese animation production company, see A.C.G.T.
Base pairing: Two base pairs are produced by four nucleotide monomers, nucleobases are in blue. Guanine (G) is paired with cytosine (C) via three hydrogen bonds, in red. Adenine (A) is paired with uracil (U) via two hydrogen bonds, in red.
Purine nucleobases are fused-ring molecules.
Pyrimidine nucleobases are simple ring molecules.
Nucleobases, also known as nitrogenous bases or often simply bases, are nitrogen-containing biological compounds that form nucleosides, which in turn are components of nucleotides, with all of these monomers constituting the basic building blocks of nucleic acids. The ability of nucleobases to form base pairs and to stack one upon another leads directly to long-chain helical structures such as ribonucleic acid (RNA) and deoxyribonucleic acid (DNA).
Five nucleobases—adenine (A), cytosine (C), guanine (G), thymine (T), and uracil (U)—are called primary or canonical. They function as the fundamental units of the genetic code, with the bases A, G, C, and T being found in DNA while A, G, C, and U are found in RNA. Thymine and uracil are identical excepting that T includes a methyl group that U lacks.
Adenine and guanine have a fused-ring skeletal structure derived of purine, hence they are called purine bases. Similarly, the simple-ring structure of cytosine, uracil, and thymine is derived of pyrimidine, so those three bases are called the pyrimidine bases. Each of the base pairs in a typical double-helix DNA comprises a purine and a pyrimidine: either an A paired with a T or a C paired with a G. These

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Retrieved Text: Nucleic acids are the fourth class of biological molecule. They store information. A nucleic acid is a nitrogen containing biological polymer that is involved in storage and transmission of genetic information.
The monomer that makes up a nucleic acid is called a nucleotide. Each nucleotide has three parts: 1. Inorganic phosphate group, 2. A five-carbon monosaccharide sugar, and 3. A nitrogen base.
In a nucleic acid, the sugar of one bonds to the phosphate of another. This makes them string together in a chain. Each sugar is also bonded to a nitrogen base.
DNA and RNA are nucleic acids. DNA carries genetic information. RNA allows cells to use the information found in DNA, and determines the sequence of amino acids that form proteins. DNA consists of two long chains of nucleotides wound together to form a spiral structure. The sugar is deoxyribose, and there are four nitrogen bases: adenine, thymine, guanine and cytosine. RNA is single stranded, and the sugar is ribose, with nitrogen bases A C G and U, which is uracil.

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Retrieved Text: Computer artwork of DNA (deoxyribonucleic acid) nucleotides, or bases. DNA is composed of four nucleotides: adenine (bottom), cytosine (top), guanine (left) and thymine (right). These make up the genetic code of every living organism. Long rows of nucleotides join by base pairing and coil into a double-helix shape. Adenine only pairs with thymine, and guanine only pairs with cytosine.

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Retrieved Text: A nitrogenous base, or nitrogen-containing base, is an organic molecule with a nitrogen atom that has the chemical properties of a base. The main biological function of a nitrogenous base is to bond nucleic acids together. A nitrogenous base owes its basic properties to the lone pair of electrons of a nitrogen atom.
Nitrogenous bases are typically classified as the derivatives of two parent compounds, pyrimidine and purine. They are non-polar and due to their aromaticity, planar. Both pyrimidines and purines resemble pyridine and are thus weak bases and relatively unreactive towards electrophilic aromatic substitution.
In the biological sciences, nitrogenous bases are increasingly termed nucleobases because of their role in nucleic acids - their flat shape is particularly important when considering their roles as the building blocks of DNA and RNA. A set of five nitrogenous bases is used in the construction of nucleotides, which in turn build up nucleic acids like DNA and RNA. These nitrogenous bases are adenine (A), uracil (U), guanine (G), thymine (T), and cytosine (C). Thymine and uracil are distinguished by merely the presence or absence of a methyl group on the fifth carbon (C5) of these heterocyclic six-membered rings. The nitrogenous bases form hydrogen bonds between opposing DNA strands to form the rungs of the "twisted ladder" or double helix of DNA or a biological catalyst that is found in the nucleotides. Adenine is always paired with thymine, and guanine is always paired with cytosine. These are known as base pairs. Adenine forms two hydrogen bonds with thymine in DNA and two

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Retrieved Text: ﻿ What Is The Structure Of A DNA Molecule?
A molecule of DNA is double-stranded. The molecule has the shape of a double helix.
The DNA molecule consists of two complementary strands oriented in an anti-parallel fashion. Each strand is composed of nucleotides. A nucleotide consists of a base (a purine or pyrimidine), a sugar (between the other two components) named deoxyribose, and a phosphate group. Nucleotides are linked to each other via phosphodiester bonds, forming a sugar-phosphate backbone to each strand.
The base of each nucleotide projects into the interior cavity of the helix. Each base is opposite another base: adenine (a purine) is always paired with thymine (a pyrimidine), and guanine (purine) with cytosine (pyrimidine); this phenomenon is called complementary base pairing.
Each nucleotide forms hydrogen bonds with its complementary base on the other strand. Two hydrogen bonds form between adenine and thymine; three hydrogen bonds form between guanine and cytosine.
What is the difference between the law of multiple proportions and the law of definite proportions? What is a medicine dropper?

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Retrieved Text: There is only one type of DNA.
The sugar in DNA is deoxyribose.
There a 2 strands held together in DNA.
DNA has 4 nitrogenous bases which are Thymine, Adenine, Cytosine, Guanine.
DNA replicates another copy of itself through mitosis and meiosis.
There are 3 different types of RNA. Messenger RNA (mRNA), Ribosomal RNA (rRNA), Transfer RNA (tRNA).
The sugar in RNA is ribose.
RNA is single stranded and connects with an anti-codon.
RNA has 4 nitrogenous bases which are Uracil, Adenine, Cytosine, and Guanine.
mRNA is transcribed from DNA.

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Retrieved Text: Nucleosides are the precursor molecules for the monomers (nucleotides) that make up the nucleic acids DNA and RNA. They consist of glycoslyamines made by attaching an organic nucleobase (like adenine, cytosine, guanine, uracil or thymine) to a five-carbon (pentose) ribose sugar ring for RNA or to a deoxyribose ring for DNA. They are converted into nucleotides by the addition of a phosphate group in the process of phosphorylation. They can also be formed by partial hydrolysis of a nucleic acid. Nucleotides are single monomer units for DNA and RNA molecules consisting of a base nucleoside, adenine, thymine, guanine or cytosine, a ribose or deoxyribose sugar and a phosphate group. Adenine, guanine and cytosine occur in both RNA and DNA. Thymine occurs only in DNA and uracil only in RNA. They are abbreviated A, G, C and T in DNA and A, G, C and U in RNA. Thousands of nucleotides linked together make up a DNA or RNA molecule. The base sequences in DNA and RNA contain the genetic information of a cell. The sequence of the bases within the nucleic acid determines which proteins will be made. The sequence of a DNA or RNA molecule is usually described as the sequence of its bases, e.g. AAAAGTTCGTCTAGGTC. Three nucleotides in a gene form a codon that encodes a single amino acid in a protein sequence. Ribose-containing nucleosides include ribonucleoside monophosphate (NMP), ribonucleoside diphosphate (NDP), and ribonucleoside triphosphate (NTP). When the nucleoside contains the sugar deoxyribose, the nucleotides are called deoxyribonucleoside mono-, di-, or tri-phosphates (dNMP, dNDP,

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Retrieved Text: Kornberg's success in unraveling the process of coenzyme synthesis established him as a biochemist by the early 1950s. It had also suggested to him that other large molecules such as the nucleic acids RNA and DNA would be synthesized in a similar way. He began his investigations into nucleic acid synthesis during the same years that James Watson and Francis Crick, among others, were trying to work out the likely structure of DNA. DNA had been shown to be the stuff of genetic inheritance. Its chemical composition was known, and Erwin Chargaff had noted that the amounts of adenine and cytosine bases always matched, respectively, the amounts of thymine and guanine bases in any given DNA sample. But nobody had a clue about how cells actually made DNA. Based on his experience with coenzymes, Kornberg guessed that DNA or RNA would be made in cells by an enzyme that would string together whole nucleotides rather than assemble smaller chemical pieces. If the nucleotides--a nitrogenous base (adenine, cytosine, guanine, thymine, or uracil) attached to a sugar (ribose or deoxyribose) and a phosphate group--were the basic building blocks, Kornberg needed to know how to make them. Several other researchers were working on the synthesis of adenine and guanine nucleotides, so Kornberg began with those of cytosine, thymine, and uracil. In this work, he moved to using microbes such as yeasts for his raw material, rather than animal tissue, and also employed the new techniques of radioisotope labeling and ion-exchange chromatography to track reactions and products.
In 1953, soon after

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Retrieved Text: We all Know that the information in DNA is stored as a code made up of four chemical bases: adenine (A), guanine (G), cytosine (C), and thymine (T). DNA bases pair up with each other, A with T and C with G, to form units called base pairs.
Now, we give you one part of a DNA sequence, can you tell me another.
For each test case, you have to output another part of the DNA. One case, one line.

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Retrieved Text: Deoxyribonucleic acid (/diˈɒksiˌraɪboʊnjʊˌkliːɪk, -ˌkleɪɪk/; DNA) is a molecule that carries the genetic instructions used in the growth, development, functioning and reproduction of all known living organisms and many viruses. DNA and RNA are nucleic acids; alongside proteins, lipids and complex carbohydrates (polysaccharides), they are one of the four major types of macromolecules that are essential for all known forms of life. Most DNA molecules consist of two biopolymer strands coiled around each other to form a double helix.
The two DNA strands are termed polynucleotides since they are composed of simpler monomer units called nucleotides. Each nucleotide is composed of one of four nitrogen-containing nucleobases—either cytosine (C), guanine (G), adenine (A), or thymine (T)—and a sugar called deoxyribose and a phosphate group. The nucleotides are joined to one another in a chain by covalent bonds between the sugar of one nucleotide and the phosphate of the next, resulting in an alternating sugar-phosphate backbone. The nitrogenous bases of the two separate polynucleotide strands are bound together (according to base pairing rules (A with T, and C with G) with hydrogen bonds to make double-stranded DNA. The total amount of related DNA base pairs on Earth is estimated at 5.0 x 1037, and weighs 50 billion tonnes. In comparison, the total mass of the biosphere has been estimated to be as much as 4 trillion tons of carbon (TtC).
WHITEOUT CLOUDMAKER DNA AND SX PANELS!!!!!!
Thread by: MoneymanVape, 11/2/18, 2 replies, in forum: Help My Vape Broke!
Hi there, i was wondering if anybody knows where i can get a dna 250

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Retrieved Text: To date, the field of ancient DNA has relied almost exclusively on mitochondrial DNA (mtDNA) sequences. However, a number of recent studies have reported the successful recovery of ancient nuclear DNA (nuDNA) sequences, thereby allowing the characterization of genetic loci directly involved in phenotypic traits of extinct taxa. It is well documented that postmortem damage in ancient mtDNA can lead to the generation of artifactual sequences. However, as yet no one has thoroughly investigated the damage spectrum in ancient nuDNA. By comparing clone sequences from 23 fossil specimens, recovered from environments ranging from permafrost to desert, we demonstrate the presence of miscoding lesion damage in both the mtDNA and nuDNA, resulting in insertion of erroneous bases during amplification. Interestingly, no significant differences in the frequency of miscoding lesion damage are recorded between mtDNA and nuDNA despite great differences in cellular copy numbers. For both mtDNA and nuDNA, we find significant positive correlations between total sequence heterogeneity and the rates of type 1 transitions (adenine → guanine and thymine → cytosine) and type 2 transitions (cytosine → thymine and guanine → adenine), respectively. Type 2 transitions are by far the most dominant and increase relative to those of type 1 with damage load. The results suggest that the deamination of cytosine (and 5-methyl cytosine) to uracil (and thymine) is the main cause of miscoding lesions in both ancient mtDNA and nuDNA sequences. We argue that the problems presented by postmortem damage, as well as problems with contamination from exogenous sources of conserved nuclear genes, allelic variation, and

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Retrieved Text: Guanine is the most readily oxidized of the four DNA bases, and guanine oxidation products cause G:C-T:A and G:C-C:G transversions through DNA replication. 8-Oxo-7,8-dihydroguanine (8-oxoG) causes G:C-T:A transversions but not G:C-C:G transversions, and is more readily oxidized than guanine. This review covers four major findings. (i) 2,2,4-Triamino-5(2H)-oxazolone (Oz) is produced from guanine and 8-oxoG under various oxidative conditions. Guanine is incorporated opposite Oz by DNA polymerases, except REV1. (ii) Several enzymes exhibit incision activity towards Oz. (iii) Since the redox potential of GG is lower than that of G, contiguous GG sequences are more readily oxidized by a one-electron oxidant than a single guanine, and OzOz is produced from GG in double-stranded DNA. Unlike most DNA polymerases, DNA polymerase ζ efficiently extends the primer up to full-length across OzOz. (iv) In quadruplex DNA, 3′-guanine is mainly damaged by one-electron oxidation in quadruplex DNA, and this damage depends on the highest occupied molecular orbital (HOMO). The oxidation products in quadruplex DNA are different from those in single-stranded or double-stranded DNA.
Cellular DNA is constantly oxidized by various endogenous and exogenous agents, and the resulting DNA damage may increase the risk of developing cancer and other diseases . Guanine has the lowest redox potential of the four DNA bases  and is therefore the most easily oxidized.
During DNA replication, adenine incorporation opposite a guanine oxidation product induces a G:C-T:A transversion, whereas guanine incorporation opposite a guanine oxidation product causes a G:C-C:G transversion. These mutations (see references in ) are found in many important genes, and in particular at CpG

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Retrieved Text: Lovers that mirror each other's drinking habits are more likely to stay together, research on 47,000 couples has revealed.
Researchers suggest that this could be down to a gene that influences how much we drink, as well as how it affects us.
Heavier drinkers were more likely to pair up and stay with partners who also regularly consume alcohol, with light-drinkers attracted to others of their ilk.
Each person in these couples were also found to be more likely to share a specific variant of a gene linked with heavy or light alcohol consumption.
They looked at each person's reported alcohol consumption and compared with those carrying a gene variant known as the ADH1B gene.
A different variant of this gene is also connected to whether we experience unpleasant side effects of alcohol, with heavy drinkers less likely to experience as severe hangovers.
Laurence Howe, a PhD student at the University of Bristol told the New Scientist that previous studies on the link between alcohol use and partner choice have relied mostly on self-reported data.
'We wanted to disentangle the possibilities using a genetic approach.
The results also suggest that a partner's drinking can have a small effect on how much we drink.
Experts found that each extra unit that a partner drinks each week corresponded to a 0.26 increase in their other half's drinking.
While the link is interesting, researchers point out that variants of ADH1B is also linked to other factors that could influence our choice of partner.
That includes heavy drinking variant being linked to being from a poorer background.
The full findings of the

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Retrieved Text: Nucleic acids, such as deoxyribonucleic acid (DNA) and ribonucleic acid (RNA), are composed of smaller subunits called nucleotides. They have a sugar-phosphate backbone and can be single or double stranded. A nucleotide is an organic compound composed of three parts: a sugar (either ribose or deoxyribose), at least one phosphate group, and a nitrogen-containing base. The base can have a single- or double-ring structure. Nucleotides have many functions. In addition to acting as the building blocks for nucleic acids, nucleotides can act as energy carriers, as coenzymes, and as chemical messengers.
All nucleotides are composed of three parts: a sugar (either ribose or deoxyribose), at least one phosphate group, and a nitrogen-containing base.
DNA is a double-stranded molecule that consists of four types of nucleotides: adenine, thymine, guanine, and cytosine. RNA is usually single stranded and also consists of four types of nucleotides. Deoxyribose is different from the ribose sugar in RNA, as the 2′ hydroxyl group is replaced with a hydrogen. Unlike DNA, RNA contains the nitrogenous base uracil, in place of thymine. Like protein synthesis, the process of DNA and RNA synthesis from nucleotides occurs via a series of condensation reactions. Several nucleotides bond together through the formation of phosphate ester linkages. This happens when the hydroxyl group of a phosphate from one nucleotide participates in a condensation reaction with the hydroxyl group on the carbohydrate ring from a different nucleotide. As this reaction proceeds, nucleotides link together, forming a nucleic acid molecule. In terms of structure, the 5′ and 3′ end of carbons attached to

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Retrieved Text: Biochemistry. 2010 Mar 23;49(11):2502-9. doi: 10.1021/bi902195p.
Crystal structure of a replicative DNA polymerase bound to the oxidized guanine lesion guanidinohydantoin.
Aller P1, Ye Y, Wallace SS, Burrows CJ, Doublié S.
Department of Microbiology and Molecular Genetics, Stafford Hall, University of Vermont, Burlington, Vermont 05405, USA.
The oxidation of guanine generates one of the most common DNA lesions, 8-oxo-7,8-dihydroguanine (8-oxoG). The further oxidation of 8-oxoG can produce either guanidinohydantoin (Gh) in duplex DNA or spiroiminodihydantoin (Sp) in nucleosides and ssDNA. Although Gh can be a strong block for replicative DNA polymerases such as RB69 DNA polymerase, this lesion is also mutagenic: DNA polymerases bypass Gh by preferentially incorporating a purine with a slight preference for adenine, which results in G.C --> T.A or G.C --> C.G transversions. The 2.15 A crystal structure of the replicative RB69 DNA polymerase in complex with DNA containing Gh reveals that Gh is extrahelical and rotated toward the major groove. In this conformation Gh is no longer in position to serve as a templating base for the incorporation of an incoming nucleotide. This work also constitutes the first crystallographic structure of Gh, which is stabilized in the R configuration in the two polymerase/DNA complexes present in the crystal asymmetric unit. In contrast to 8-oxoG, Gh is found in a high syn conformation in the DNA duplex and therefore presents the same hydrogen bond donor and acceptor pattern as thymine, which explains the propensity of DNA polymerases to incorporate a purine opposite Gh when bypass occurs.
Oxidation products of guanine. 8-oxoguanine is the oxidation product of guanine, and

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Retrieved Text: Describe why the cell makes polymers and the important polymers of the cell.
Explain how sugars monomers are put together to make polymers.
Explain the chemical and structural differences between DNA and RNA.
Living systems are made of organic molecules, and the cell has settled on just a few types of molecules to make up the majority of its structures: sugars, nucleic acids, amino acids and lipids. It is somewhat shocking that the list is so short, but it demonstrates the elegance of the whole system.
Monomers are all well and good, but cells are much larger than the molecular scale. How do they do it? These single molecular units are linked together by the cellular machinery into long chains of monomers, called polymers. Polymers make up the bulk of what a cell is, dictating its structure and function. Proteins are polymers of amino acids and they drive the chemical reactions of the cell or serve as parts of important structures. Starch is a polymer of glucose and polysaccharides are polymers of sugars that serve in the cell wall, the cell membrane and as storage products. DNA is a polymer of nucleic acids and is the library that stores the recipes for making an organism.
For polymers made up of more than one monomer, there are several important implications. How each polymer behaves is dictated by the order in which the monomers appear in the sequence of the polymer. Each specific combination of monomers will create a unique polymer that has a specific structure and function. Changing any one of the

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Retrieved Text: Structure and Function of the DNA Molecule - What DNA test?
You probably know that the DNA is the physical support of our genetic information and that it is a double helix molecule. Lets see its structure and function with a little bit more of detail.
Figure 1. DNA double helix.
In figure 1 you can see a fragment of DNA. The backbone is in the outside in green (deoxyribose sugar) and red (phosphate) whereas the nitrogenated bases are in the inside in blue. There are four different nitrogenated basis and they always pair up the same way due to their chemical structure: adenine with thymine (figure 2) and guanine with cytosine (figure 3). If we cut a section of the DNA, one nitrogenated base plus one deoxyribose plus one phosphate is called a nucleotide. And a nucleotide and the complementary one in the other strand is called a base pair.
The pairing of the nitrogenated basis is what holds together the two strands of the DNA double helix. And it is very important for the replication of the DNA: since the pairing of nitrogenated basis is always A-T and C-G, you can separate the two strands of DNA and build a complementary strand for each as there is only one complementary nitrogenated base for each position.
Figure 2. Adenine – Thymine.
Figure 3. Guanine – Cytosine.
The DNA is a very long molecule and it is highly packed in the nucleus of the cells. In figure 4 we can see how the double helix coils around the histones (the gray balls in

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Retrieved Text: Pyrimidine is an aromatic heterocyclic organic compound similar to pyridine. One of the three 2 positions). In nucleic acids, three types of nucleobases are pyrimidine derivatives: cytosine (C), thymine (T), and uracil (U). It is also found in many synthetic compounds such as barbiturates and the HIV drug, zidovudine. There are two kinds of nitrogen-containing bases - purines and and the endproduct of purine catabolism, which is uric acid in man, may serve. Purine contains two carbon-nitrogen rings and four nitrogen atoms. Purines have high meting point. Pyrimidines contains one carbon-nitrogen.
Double-ringed Purine / Single-ringed Pyrimidine bases. The purines are G The pyrimidines in DNA are C & T. In RNA, U replaces T; thymine is 5-methyl-uracil. In DNA, there are four different bases: adenine (A) and guanine (G) are the larger purines. Cytosine (C) and thymine (T) are the smaller pyrimidines. RNA also. There are many derivatives of this structure through the addition of one or The three pyrimidine nitrogenous bases, thymine (T), cytosine (C), and uracil (U).
According to Chargaff's rules which states that DNA from any cell of all organisms should have a ratio (base Pair Rule) of Purine and Pyrimidine bases, i.e. (Elements & Compounds) Also called: pyrimidine base any of a number of similar compounds having a basic structure that is derived from pyrimidine, including. Purines and pyrimidines are the two families of nitrogenous bases that While they are similar in many respects, there are a number of key. A base pair is one of the pairs A-T or C-G. Notice that each

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Retrieved Text: For the similarly spelled B vitamin, see Thiamine.
Thymine /ˈθaɪmᵻn/ (T, Thy) is one of the four nucleobases in the nucleic acid of DNA that are represented by the letters G–C–A–T. The others are adenine, guanine, and cytosine. Thymine is also known as 5-methyluracil, a pyrimidine nucleobase. In RNA, thymine is replaced by the nucleobase uracil. Thymine was first isolated (from calves' thymus glands) in 1893 by Albrecht Kossel and Albert Neumann.
As the name suggests, thymine may be derived by methylation of uracil at the 5th carbon. In RNA, thymine is replaced with uracil in most cases. In DNA, thymine (T) binds to adenine (A) via two hydrogen bonds, thus stabilizing the nucleic acid structures.
Thymine combined with deoxyribose creates the nucleoside deoxythymidine, which is synonymous with the term thymidine. Thymidine can be phosphorylated with one, two, or three phosphoric acid groups, creating, respectively, TMP, TDP, or TTP (thymidine mono-, di-, or triphosphate).
One of the common mutations of DNA involves two adjacent thymines or cytosine, which, in presence of ultraviolet light, may form thymine dimers, causing "kinks" in the DNA molecule that inhibit normal function.
Thymine could also be a target for actions of 5-fluorouracil (5-FU) in cancer treatment. 5-FU can be a metabolic analog of thymine (in DNA synthesis) or uracil (in RNA synthesis). Substitution of this analog inhibits DNA synthesis in actively dividing cells.
Thymine bases are frequently oxidized to hydantoins over time after the death of an organism.
Thymine is a nuclear base.
This page was last modified on 3 October 2015, at 23:35.

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Retrieved Text: DNA is found inside a special area of the cell called the nucleus. Because the cell is very small, and because organisms have many DNA molecules per cell, each DNA molecule must be tightly packaged. This packaged form of the DNA is called a chromosome.
The four types of nitrogen bases found in nucleotides are: adenine (A), , thymine (T), guanine (G) and cytosine (C). The order, or sequence, of these bases determines what biological instructions are contained in a strand of DNA. For example, the sequence ATCGTT might instruct for blue eyes, while ATCGCT might instruct for brown.
The German biochemist Frederich Miescher first observed DNA in the late 1800s. But nearly a century passed from that discovery until researchers unraveled the structure of the DNA molecule and realized its central importance to biology.

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Retrieved Text: Deoxyribonucleic acid is better known by its shorter name DNA. The determination of DNA’s structure in 1953 by Francis Crick and Jim Watson is hailed by many to be the most important discovery ever in human history.
DNA is life’s hereditary material, i.e. it holds and passes on the genetic information from parents to offspring. The information carried by DNA directs the construction of each organism, its maintenance, proper functioning and reproduction.
The information is carried in coded form as sequence of specific chemicals called nitrogenous bases. Just as a computer code is a unique sequence of 0s and 1s, so is life’s genetic code a unique sequence of bases.
There are about 2.5 metres of DNA in the nuclear DNA of each human cell. Therefore, we each have about 250 billion kilometres of DNA in our body. Every second we make enough DNA to encircle the equator 3 times. We make about 50 million new cells every second.
DNA structure is described as a double helix. It is like a spiral ladder and is composed of two complementary polynucleotide strands held together by hydrogen bonds.
In DNA the sugar is deoxyribose and because there are four different bases – adenine (A), guanine (G), thymine (T) and cytosine (C) - there are four different nucleotides. The nucleotides are PSA, PSG, PST, PSC.

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Retrieved Text: There are no GMO foods or ingredients that have pork DNA inserted into them.
There was once an experimental tomato that contained a gene from the winter flounder to increase the tomato's resistance to frost, but that tomato was never commercialized. While that tomato did not survive, its legend continues to live on in online search engines. While there are many fake images online featuring fishy tomatoes, there are, in fact, no GMO tomatoes commercially available today.
No commercial GM crops on the market today contain “animal genes.” DNA from any source is made up of the same four basic nucleotide building blocks: adenine (A), cytosine (C), thymine (T) and guanine (G), and it’s estimated that 60 percent of the genes in plants have very similar copies in animals. Although no GM crops on the market today contain “animal genes,” there is nothing inherently unsafe about using fish DNA (or any other animal DNA) in a plant. Learn more about DNA and animal genes here.
We hope this information answers your question. If you have any further questions, please ask.

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Retrieved Text: Widespread throughout animal and plant tissue, purine components of DNA, RNA, and coenzymes. Vitamin Adenine (sometimes known as vitamin B4) combines with the sugar ribose to form adenosine, which in turn can be bonded with from one to three phosphoric acid units, yielding AMP, ADP and ATP . These adenine derivatives perform important functions in cellular metabolism. Adenine is one of four nitrogenous bases utilized in the synthesis of nucleic acids. A modified form of adenosine monophosphate (cyclic AMP) is an imporant secondary messenger in the propagation of many hormonal stimuli. Adenine is an integral part of the structure of many coenzymes. Adenosine (adenine with a ribose group) causes transient heart block in the AV node of the heart. In individuals suspected of suffering from a supraventricular tachycardia (SVT), adenosine is used to help identify the rhythm. Certain SVTs can be successfully terminated with adenosine.; Adenine forms adenosine, a nucleoside, when attached to ribose, and deoxyadenosine when attached to deoxyribose. It forms adenosine triphosphate (ATP), a nucleotide, when three phosphate groups are added to adenosine. Adenosine triphosphate is used in cellular metabolism as one of the basic methods of transferring chemical energy between chemical reactions.; Adenine is a nucleobase (a purine derivative) with a variety of roles in biochemistry including cellular respiration, in the form of both the energy-rich adenosine triphosphate (ATP) and the cofactors nicotinamide adenine dinucleotide (NAD) and flavin adenine dinucleotide (FAD), and protein synthesis, as a chemical component of DNA and RNA. The shape of adenine is complementary to either thymine in DNA

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Retrieved Text: Figure 2.23 Formulas of Purines and Pyrimidines DNA contains the pyrimidine thymine. RNA contains uracil in place of thymine.
Figure 2.22 A Nucleotide This is one subunit of DNA.This subunit is called adenylic acid or deoxyadenosine-5'-phosphate because the base is adenine. If the base is thymine, the nucleotide is thymidylic acid; if guanine, guanylic acid; and if cytosine, cytidylic acid. If the nucleotide lacks the phosphate molecule, it is called a nucleoside, in this case, deoxyadenosine.
Figure 2.24 Joining Nucleotide Subunits (a) Formation of covalent bond between nucleotides by dehydration synthesis. (b) Chain of nucleotides showing the differences between 5' end and 3' end.The chain always is extended at the 3' end, which has the unbonded —OH hydroxyl group.

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Input Text: Answer the following question given this paragraph: 

Transport vesicles are part of the endomembrane system. They are able to move molecules such as proteins between locations inside the cell. For example, transport vesicles move proteins from the rough endoplasmic reticulum to the Golgi apparatus.


Q: Transport vesicles move what type of molecules from the rough endoplasmic reticulum to the golgi apparatus?

 Choices:

- proteins

- hormones

- acids

- lipids

A:

Target Text: proteins

#### Retrieved Documents ####

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Retrieved Text: Endoplasmic Reticulum, or ER for short, are organelles found near the nucleus in many cells that form a network of complex sacs throughout the cell. They are important in the synthesis of proteins , special chemicals, and enzymes needed for the cell to function, and they transport materials through the inside of the cell. Endoplasmic Reticulum also come in two types, Rough ER and Smooth ER. In macrophages, Endoplasmic Reticulum are important in the production of enzymes needed to digest materials that it consumes.
The surface of rough ER is covered with Ribosomes, giving it a rough appearance, hence the name. Rough ER help synthesize, modify, and transport proteins.
Smooth ER do not have any ribosomes attatched to their surface, which gives them their smooth appearance. They contain enzymes for the production of lipids and other chemicals, and they transport molecules from the Rough ER to the Golgi Apparatus by pinching off small sections containing the molecules and forming transition vesicles.

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Retrieved Text: The endoplasmic reticulum or ER is an organelle found in all eukaryotic cells that is an interconnected network of tubules, vesicles and cisternae. The lacey membranes of the endoplasmic reticulum were first seen by Keith R. Porter, Albert Claude, and Ernest F. Fullam in 1945. These structures are responsible for several specialized functions: Protein translation, folding, and transport of proteins to be used in the cell membrane (e.g., transmembrane receptors and other integral membrane proteins), or to be secreted (exocytosed) from the cell (e.g., digestive enzymes); sequestration of calcium; and production and storage of glycogen, steroids, and other macromolecules. The endoplasmic reticulum is part of the endomembrane system. The basic structure and composition of the ER membrane is similar to the plasma membrane.
The general structure of the endoplasmic reticulum is an extensive membrane network of cisternae (sac-like structures) held together by the cytoskeleton. The phospholipid membrane encloses a space, the cisternal space (or lumen), from the cytosol. The functions of the endoplasmic reticulum vary greatly depending on the exact type of endoplasmic reticulum and the type of cell in which it resides. The three varieties are called rough endoplasmic reticulum, smooth endoplasmic reticulum, and sarcoplasmic reticulum.
The surface of the rough endoplasmic reticulum is studded with protein-manufacturing ribosomes giving it a "rough" appearance (hence its name). But it should be noted that these ribosomes are not resident of the endoplasmic reticulum initially. The ribosomes only bind to the ER once it begins to synthesize a protein destined for sorting. The free ribosome begins producing the polypeptide until

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Retrieved Text: Mitosis is the part of a cell reproduction cycle that results in identical daughter nuclei that are also genetically identical to the original parent nucleus.
In addition to the presence of nuclei, eukaryotic cells are distinguished by an endomembrane system that includes the plasma membrane, nuclear envelope, lysosomes, vesicles, endoplasmic reticulum, and Golgi apparatus. These subcellular components work together to modify, tag, package, and transport proteins and lipids. The rough endoplasmic reticulum (RER) with its attached ribosomes is the site of protein synthesis and modification. The smooth endoplasmic reticulum (SER) synthesizes carbohydrates, lipids including phospholipids and cholesterol, and steroid hormones; engages in the detoxification of medications and poisons; and stores calcium ions. Lysosomes digest macromolecules, recycle worn-out organelles, and destroy pathogens. Just like your body uses different organs that work together, cells use these organelles interact to perform specific functions. For example, proteins that are synthesized in the RER then travel to the Golgi apparatus for modification and packaging for either storage or transport. If these proteins are hydrolytic enzymes, they can be stored in lysosomes. Mitochondria produce the energy needed for these processes. This functional flow through several organelles, a process which is dependent on energy produced by yet another organelle, serves as a hallmark illustration of the cell’s complex, interconnected dependence on its organelles.
A substance that helps a chemical reaction to occur is a catalyst, and the special molecules that catalyze biochemical reactions are called enzymes. Almost all enzymes are proteins, made up of chains of amino acids, and they perform the critical task of

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Retrieved Text: The endoplasmic reticulum (ER)-Golgi system has been studied using biochemical, genetic, electron and light microscopic techniques leading to an understanding of many aspects of trafficking from the ER to the Golgi apparatus (Murshid and Presley 2004). This includes some of the signals and mechanisms for selective retention and retrieval of ER resident proteins and export of cargo proteins. Proteins that leave the ER emerge in 'export complexes' or ER 'exit sites' and accumulate in pleiomorphic transport carriers referred to as VTCs or intermediate compartments. These structures then transit from the ER to the Golgi apparatus along microtubules using the dynein/dynactin motor and fuse with the cis cisterna of the Golgi apparatus. Many proteins (including vSNAREs, ERGIC53/p58 and the KDEL receptor) must cycle back to the ER from pre-Golgi intermediates or the Golgi. Murshid and Presley 2004 considered a model suggesting that this cycling occurs via 50-nm COPI-coated vesicles and in vivo evidence that suggests that retrograde trafficking may occur via tubular structures. Intracellular membrane transport involves the coordinated engagement of a series of organelles and molecular machineries that ensure that proteins are delivered to their correct cellular locations.
Due to its central position in the secretory pathway and to the large amounts of signaling molecules associated with it, the Golgi complex plays a role in this regulation. The generation of autonomous signaling by the Golgi complex in response to the arrival of cargo from the endoplasmic reticulum (ER) allows that cargo moving from the ER to the Golgi activates a series of signaling pathways. This regulatory mechanism

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Retrieved Text: Organisms are composed of cells, and these cells have specific structures within in them that allow them to carry out their functions. These structures are called Organelles. The fine detail of the cell (which may be revealed by an electron microscope) is called the cell's ultrastructure. Organelles perform different functions within a cell, and this is called the Division of Labour.
The Nucleus is the largest organelle in a cell. It contains a dense structure called the Nucleolus and is surrounded by the Nuclear Envelope, a structure composed of two membranes, seperated by fluid, which contain a number of nuclear pores that can allow relatively large molecules through. The nucleus contains nearly all of the cell's genetic material. The Nucleolus creates Ribonucleic Acid and Ribosomes, which then travel out of the nucleus, through the nuclear pores, to the cytoplasm where they are involced in Protein Synthesis.
The Endoplasmic Reticulum (ER) is found near the Nucleas and is made up of a number of flattened sacs called Cisternae, which are continuous with the Nuclear Envelope. The Rough Endoplasmic Reticulum is called so because it has a lot of Ribosomes on its outer surface. The Smooth Endoplasmic Reticulum however, does not have Ribosomes. The Rough transports proteins that are synthesised in the Ribosomes, and the Smooth synthesises Lipids.
The Golgi Apparatus is a stack of membrane bound flattened sacs, and are responsible for the modification of proteins received from the ER. These proteins are then transported in vesicles around the cell.
Lysosomes are membrane bound spherical sacs which contain digestive enzymes used

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Retrieved Text: This lecture introduces how information is transferred from stable stored information (DNA) converted to an intermediate (mRNA, rRNA, tRNA) of variable stability, exported from the nucleus to the cytoplasm where mRNA is then translated into Protein. This is gene expression, the products of this process are used either within the cell, exported (exocytosis) or used to replace worn out components.
We will study this topic at the level of the cellular components and organelles involved in the process: ribosomes, endoplasmic reticulum, Golgi apparatus, vesicles (transport and secretory). Now watch the movie in this introduction.
Please note this lecture will now be combined with endocytosis cytosine lecture.
MH - note that archive content listed above will not match exactly current lecture structure but has been selected as having similar content.
Below are some example historical research finding related to exocytosis from the JCB Archive.
1955 Ribosomes, or the particles of Palade George Palade identifies particulate components of the cytoplasm, known initially as the particles of Palade and later as ribosomes.
1956 Microsomes are the in vitro ER George Palade and Philip Siekevitz unite the fields of microscopy and fractionation in this work. They conclude that Albert Claude’s biochemical fraction called microsomes are the in vitro version of the endoplasmic reticulum (ER) — a cytological feature first noted by Keith Porter.
1958 A pathway for secretion Radioactive proteins are followed after their synthesis as they progress towards their secretory fate; this allows the definition of not only trafficking pathways but of the organelles that lie along that pathway.
1966 Excess secretory products fuse with lysosomes Robert

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Retrieved Text: The small GTPases Rab are key regulators of intracellular membrane trafficking, from the formation of transport vesicles to their fusion with membranes. Rabs cycle between an inactive GDP-bound form and an active GTP-bound form that is able to recruit to membranes different set of downstream effectors directly responsible for vesicle formation, movement, tethering and fusion. That Rab may play a role in protein transport from recycling endosomes to lysosomes regulating, for instance, the degradation of the transferrin receptor. Involved in autophagy. Interacts with RABIF and OPTN.
UniProt: RAB12 is active in the following subcellular-locations: autophagosome, cytoplasmic vesicle, golgi apparatus membrane, lysosome membrane, recycling endosome membrane.
GO terms: RAB12 is active in the following subcellular-locations: autophagosome, cytosol, endoplasmic reticulum membrane, Golgi membrane, lysosomal membrane, lysosome, phagocytic vesicle, recycling endosome membrane, trans-Golgi network.

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Retrieved Text: Golgi Apparatus: A stack of flattened vesicles that functions in posttranslational processing and sorting of proteins, receiving them from the rough ENDOPLASMIC RETICULUM and directing them to secretory vesicles, LYSOSOMES, or the CELL MEMBRANE. The movement of proteins takes place by transfer vesicles that bud off from the rough endoplasmic reticulum or Golgi apparatus and fuse with the Golgi, lysosomes or cell membrane. (From Glick, Glossary of Biochemistry and Molecular Biology, 1990)Brefeldin A: A fungal metabolite which is a macrocyclic lactone exhibiting a wide range of antibiotic activity.Endoplasmic Reticulum: A system of cisternae in the CYTOPLASM of many cells. In places the endoplasmic reticulum is continuous with the plasma membrane (CELL MEMBRANE) or outer membrane of the nuclear envelope. If the outer surfaces of the endoplasmic reticulum membranes are coated with ribosomes, the endoplasmic reticulum is said to be rough-surfaced (ENDOPLASMIC RETICULUM, ROUGH); otherwise it is said to be smooth-surfaced (ENDOPLASMIC RETICULUM, SMOOTH). (King & Stansfield, A Dictionary of Genetics, 4th ed)Thiamine Pyrophosphatase: An enzyme that hydrolyzes thiamine pyrophosphate to thiamine monophosphate plus inorganic phosphate. EC 3.6.1.-.Microscopy, Electron: Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the

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Retrieved Text: Our Abpromise guarantee covers the use of ab157272 in the following tested applications.
ab157272 was purified using conventional chromatography techniques.
Involved in melanosome biogenesis by ensuring the stability of GPR143. Plays a vital role in the expression, stability, trafficking, and processing of melanocyte protein PMEL, which is critical to the formation of stage II melanosomes.
Expression is restricted to melanoma and melanocyte cell lines and retina.
Endoplasmic reticulum membrane. Golgi apparatus. Golgi apparatus > trans-Golgi network membrane. Melanosome. Also found in small vesicles and tubules dispersed over the entire cytoplasm. A small fraction of the protein is inserted into the membrane in an inverted orientation. Inversion of membrane topology results in the relocalization of the protein from a predominant Golgi/post-Golgi area to the endoplasmic reticulum. Melanoma cells expressing the protein with an inverted membrane topology are more effectively recognized by specific cytolytic T-lymphocytes than those expressing the protein in its native membrane orientation.
15% SDS-PAGE analysis of ab157272 (3µg).
ab157272 has not yet been referenced specifically in any publications.
Publishing research using ab157272? Please let us know so that we can cite the reference in this datasheet.
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Retrieved Text: Hi y'all! So, I noticed while I was reading up and watching videos from the Amoeba Sisters (LOVE), Crash Course (LIKE), etc., that I had to go back and reread/re-watch crucial parts of the cell over and over again to really DRILL IT IN. I can't tell you how many times I had to go back and figure out what the hey a lysosome even is! I'll try to make it easier on you guys, because I had to do "Learn" on Quizlet to figure it out... Anyway, let's get going!
+ A eukaryotic cell has a nucleus that can contain DNA.
+ A eukaryotic cell has membrane-bound organelles.
+ A eukaryotic cell has a cell membrane & cytoskeleton.
The cell membrane: I made a whole blog about it, but basic outline, it has a hydrophilic head and a hydrophobic tail, and it acts as the gatekeeper to the cell.
The cytoplasm: It is the clear gel that surrounds the whole interior of the cell. It is sort of like the bubble wrap that wraps your whole Amazon order in bubbly "peace-of-mind-ful" comfort.
The cytoskeleton: It's only job is to make sure that the all-important cells don't exit the membrane into the environment around it, eventually causing cellular destruction! Mwa-ha-ha-ha-ha! Ahem. Yeah, so, without it, we're toast.
The mitochondria: These oblong organelles are the battery pack of the whole thing! If the cell were a city, these mitochondria would be the power lines. The purpose of the mitochondria is to make ATP, the money of the cell. See, Cell City here even has

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Retrieved Text: Transporter involved in macrophage lipid homeostasis. Is an active component of the macrophage lipid export complex. Could also be involved in intracellular lipid transport processes. The role in cellular lipid homeostasis may not be limited to macrophages. May form heterodimers with several heterologous partners of the ABCG subfamily.
UniProt: ABCG1 is active in the following subcellular-locations: endoplasmic reticulum membrane, golgi apparatus membrane.
GO terms: ABCG1 is active in the following subcellular-locations: endoplasmic reticulum membrane, endosome, external side of plasma membrane, Golgi apparatus, Golgi membrane, integral component of membrane, mitochondrion, plasma membrane, recycling endosome.

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Retrieved Text: α2-COP is involved in early secretory traffic in Arabidopsis and is required for plant growth.
COP (coat protein) I-coated vesicles mediate intra-Golgi transport and retrograde transport from the Golgi to the endoplasmic reticulum. These vesicles form through the action of the small GTPase ADP-ribosylation factor 1 (ARF1) and the COPI heptameric protein complex (coatomer), which consists of seven subunits (α-, β-, β'-, γ-, δ-, ε- and ζ-COP). In contrast to mammals and yeast, several isoforms for coatomer subunits, with the exception of γ and δ, have been identified in Arabidopsis. To understand the role of COPI proteins in plant biology, we have identified and characterized a loss-of-function mutant of α2-COP, an Arabidopsis α-COP isoform. The α2-cop mutant displayed defects in plant growth, including small rosettes, stems and roots and mislocalization of p24δ5, a protein of the p24 family containing a C-terminal dilysine motif involved in COPI binding. The α2-cop mutant also exhibited abnormal morphology of the Golgi apparatus. Global expression analysis of the α2-cop mutant revealed altered expression of plant cell wall-associated genes. In addition, a strong upregulation of SEC31A, which encodes a subunit of the COPII coat, was observed in the α2-cop mutant; this also occurs in a mutant of a gene upstream of COPI assembly, GNL1, which encodes an ARF-guanine nucleotide exchange factor (GEF). These findings suggest that loss of α2-COP affects the expression of secretory pathway genes.

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Retrieved Text: Respiration occurs in every cell of your body. To understand respiration you maty need to find out more about cells and how they work. Do you know what the major organelles of the cell are called, and what each of these structures does?
Click on the labels around the cell if you want to find out more!
When you look inside a cell you see many different structures called organelles. Each organelle has a function of its own, allowing the cell to live and work within our bodies.
The cell membrane packages up the cell and all its organelles. Water, energy, and nutrients enter the cell, and waste material leaves the cell through the cell membrane.
The cytoplasm of a cell is not really an organelle - it is the fluid the organelles are bathed in. It contains proteins, sugars and other substances that help the cell function properly.
Vacuoles are storage areas. They are surrounded by membranes and filled with liquid or solid material. Vacuoles are much bigger in plant cells.
The golgi body (or the golgi apparatus) makes some of the chemicals produced within the cell. It also collects and packages chemicals for transport to different parts of the cell.
Lysosomes contain enzymes that break down cell material (if these enzymes were not contained within lysosomes, they would eat away the cell). When organelles have 'died' they are surrounded by the lysosome and broken down by the enzymes.
There are thousands of ribosomes inside a cell. They are found in the cytoplasm, in mitochondria and they make endoplasmic reticulum rough. Ribosomes make

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Retrieved Text: Tired of Endless Searching? Find Endoplasmic Reticulum Structure on DealsNow.
Start studying Endoplasmic Reticulum. Learn vocabulary, terms, and more with flashcards, games, and other study tools.
Does the Smooth Endoplasmic Reticulum create steroids? One of the primary functions of the Smooth Endoplasmic Reticulum is to produce and move lipids, an essential component of a cell's outer membrane, and steroids.
The ribosomes are located on the cytosolic side of the endoplasmic reticulum, which is also called the ER. The presence of these ribosomes on the outer layer of the RER distinguishes it from smooth endoplasmic reticulum, which is known as the SER. In addition to producing proteins, the RER plays an essential role in many other functions.
Unformatted text preview: 1 Quizlet 2 Main function of Cytosol Are the nuclear envelope and ER double membraned? Chloroplasts Endoplasmic reticulum ER Endosomes Golgi apparatus Golgi, lysosomes, endosomes, and nuclear membrane proteins and lipids are from where? How do cytosolic proteins enter the mitochondria and chloroplasts?

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Retrieved Text: The Golgi (pronounced GOL-jee) complex (or Golgi apparatus or Golgi body) was discovered by Camillo Golgi (1844–1926), an Italian physician. While Dr. Golgi was staining neurons with silver nitrate (Golgi stain), he noticed small intracellular structures made up of vesicles and fibers known today as the Golgi complex.
The Golgi complex is composed of several layers of cisternae (fluid-filled membrane sacs) arranged like stacked pancakes near the outer edges of the endoplasmic reticulum (ER) near the nucleus . The Golgi complex is organized into three biochemically distinct compartments: the cis Golgi, the medial Golgi, and trans Golgi; the cis Golgi is closest to the ER.
The intracellular structures known at the Golgi complex are involved in protein processing and secretion.
The primary function of the Golgi complex is to modify, process, and sort newly produced proteins that arrive from the ER. These modifications include adding or deleting specific sugar molecules to modify the branched sugar structures found on newly formed proteins. For example, some of the mannose sugars are cut from the oligosaccharide branch in the cis Golgi. Upon completion of this step, the protein travels to the medial Golgi where other sugars like N-acetylglucoseamine and fucose are added to the oligosaccharide branches on the protein. Further modifications to the carbohydrates are completed in the trans Golgi. Carbohydrate additions may aid in the stability, transport, and/or function of the proteins.
Two models have been proposed to explain how newly produced proteins travel from the ER to the Golgi complex and travel among Golgi stacks. One model suggests that proteins are

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Retrieved Text: The physiology of membrane transport and endomembrane-based signalling.
In vitro reconstitution of microtubule plus end-directed, GTPgammaS-sensitive motility of Golgi membranes.
Agonist-dependent delivery of M(2) muscarinic acetylcholine receptors to the cell surface after pertussis toxin treatment.
RGS-GAIP, a GTPase-activating protein for Galphai heterotrimeric G proteins, is located on clathrin-coated vesicles.
Activation of microtubule dynamics increases neuronal growth via the nerve growth factor (NGF)- and Gαs-mediated signaling pathways.
G-protein βγ subunits are positive regulators of Kv7.4 and native vascular Kv7 channel activity.
Golgi proteins persist in the tubulovesicular remnants found in brefeldin A-treated pancreatic acinar cells.
Protein kinase C epsilon is localized to the Golgi via its zinc-finger domain and modulates Golgi function.
Coat proteins in intracellular membrane transport.
Detection of G-protein heterotrimers on large dense core and small synaptic vesicles of neuroendocrine and neuronal cells.
Export of protein from the endoplasmic reticulum is regulated by a diacylglycerol/phorbol ester binding protein.
Inhibition by somatostatin of amylase secretion induced by calcium and cyclic AMP in rat pancreatic acini.

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Retrieved Text: Required for vesicular transport between the endoplasmic reticulum and the Golgi apparatus.
Below are the list of possible Alpha-soluble NSF attachment protein products. If you cannot find the target and/or product is not available in our catalog, please click here to contact us and request the product or submit your request for custom elisa kit production, custom recombinant protein production or custom antibody production. Custom ELISA Kits, Recombinant Proteins and Antibodies can be designed, manufactured and produced according to the reer's specifications.
Also known as Alpha-soluble NSF attachment protein 1 (Alpha-SNAP1) (N-ethylmaleimide-sensitive factor attachment protein alpha 1).
Required for vesicular transport between the endoplasmic reticulum and the Golgi apparatus. Binds to SNARE complex and then recruits NSF to disassemble it ().
Also known as Alpha-soluble NSF attachment protein 2 (Alpha-SNAP2) (N-ethylmaleimide-sensitive factor attachment protein alpha 2).

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Retrieved Text: 1. 2. 3. 4. 5. Endoplasmic Reticulum, Golgi complex, Endosomes, Lysosomes, and Vacuoles.
The organelles of the endomembrane system are part of a dynamic, integrated network in which materials are shuttled back and forth from one part of the cell to another.
Materials are shuttled between organelles mostly in small, membrane-bounded transport vesicles that bud from a donor membrane compartment Transport vesicles move through the cytoplasm in a directed manner on tracks formed by cytoskeleton When they reach their destination, the vesicles fuse with the membrane of the acceptor compartment.
1. Constitutive secretion, secreation in a continual manner.
Endocrine cells that release hormones, Release of digestive enzymes Release of neurotransmitters.
Vesicles-oval membrane bound vacuolar structures having diameter of 25-500m Often seen isolated in the cytoplasm.
Two types of ER share many of the same proteins and engage in certain common activities, such as the synthesis of certain lipids and cholesterol.
The rough ER is the starting point of the biosynthetic pathway It is the site of synthesis of the proteins, carbohydrate chains, and phospholipids that journey through the membranous compartments of the cell.
The covalent addition of sugars to the secretary proteins During this process a single species of oligosaccharide is transferred to proteins in the ER.
Also called agranular ER Ribosomes are absent on the surface of ER Seen in cells which are involved in lipids and glycogen metabolism Muscle cells are also rich in SER here it is known as sarcoplasmic reticulam In pigmented retinal cells SER is called myeloid bodies.
Contains enzymes for the synthesis of cholesterol and bile acids. Synthesis of steroid

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Retrieved Text: Anderson’s disease is also known as chylomicron retention disease which is a rare hereditary disease. It is an autosomal recessive disease characterized by low plasma lipid and low lipid-soluble vitamins (such as vitamin E and vitamin D). After the digestion of food, lipids, and lipid soluble vitamins are absorbed in the human body with the help of chylomicrons. A lack of chylomicron can interrupt the transport of molecules from intestine to the bloodstream resulting in malabsorption. Subjects with these disorders show different clinical manifestations which were initially described by Anderson and colleagues, hence it was called as “Anderson’s disease”. Genotyping has revealed that Anderson's and chylomicron retention disease are in fact the same disease.
Anderson' disease and chylomicron retention disease is the same disease which has been proved genotypically. The disease is caused by the mutation in the gene SAR1B (formerly SARA2), which encodes the SAR1B protein. Mutation results in the defect in chylomicron secretion, a transport protein. A lack of transport of dietary lipids from the intestine to the bloodstream causes malabsorption, which is the main characteristic of the disorder. Malabsorption syndrome with steatorrhea and growth retardation is usually seen in chylomicron retention disease.
Chylomicrons are the transport lipids that primarily involved in carrying of dietary lipids such as triglyceride-rich lipoproteins which are secreted generally from the enterocytes. It is produced in the endoplasmic reticulum of the absorptive cells (enterocytes) of the small intestine. These large lipoproteins range from 700 to 6000 Å size which contains a single molecule of apolipoprotein (apo) B-48. It is a sole

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Retrieved Text: Hepatocytes are the chief functional cells of the liver and perform an astonishing number of metabolic, endocrine and secretory functions. Roughly 80% of the mass of the liver is contributed by hepatocytes.
In three dimensions, hepatocytes are arranged in plates that anastomose with one another. The cells are polygonal in shape and their sides can be in contact either with sinusoids (sinusoidal face) or neighboring hepatocytes (lateral faces). A portion of the lateral faces of hepatocytes is modified to form bile canaliculi. Microvilli are present abundantly on the sinusoidal face and project sparsely into bile canaliculi.
Hepatocyte nuclei are distinctly round, with one or two prominent nucleoli. A majority of cells have a single nucleus, but binucleate cells are common. The micrographs below (H&E stain) demonstrate these features in sections of liver from a pig (left) and raccoon (right).
Hepatocytes are exceptionally active in synthesis of protein and lipids for export. As a consequence of these activities, ultrastructural examination of hepatocytes reveals bountiful quantities of both rough and smooth endoplasmic reticulum. In contrast to most glandular epithelial cells that contain a single Golgi organelle, hepatocytes typically contain many stacks of Golgi membranes. Golgi vesicles are particularly numerous in the vicinity of the bile canaliculi, reflecting transport of bile constituents into those channels.
Another important function of hepatocytes is to synthesize and secrete very low density lipoproteins. These complexes are seen in electron micrographs as electron-dense particles within smooth endoplasmic reticulum.
Left panel: from a mouse that fasted overnight and thus had very low levels glycogen in liver.
Right panel: from mouse that

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Retrieved Text: And in the last quarter we find a single Golgi apparatus. The only of the four organelles that does not appear in the other quadrants. As if working away on its corner. The less bright colours do not manage to make it look unimportant.
The vacuoles concentrate and contrast with the more complex organelles. Their complexity is not based in their structure (simple bubbles) but it is suggested by the mixing colours of their contents.
In this quarter, the endothelial reticulum covers most of the area, part of it rough with ribosomes. It is the organelle that gives the cell a continuity and the nucleus its central prominence in the composition.
This is part 1 of a 4 parts theme, the classical organelle. The four pieces form a whole ‘cell’ quartered. In each quarter one organelle takes priority: mitochondria, endoplasmic reticulum, vacuoles and Golgi apparatus. This theme, and a few of its variations were developed for Art Meets Science 2014, MDI Biological Laboratory, Maine, USA.
A moment in time inside a eukaryotic cell. Complex and beautiful, full of action and life. The fluidity of the cytoplasm, the different levels of activity of mitochondria and the communication between endoplasmic reticulum and mitochondria are the highlights of this very large work (1.2 m square).

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Retrieved Text: Deposition Author(s): Mossessova, E., Bickford, L.C., Goldberg, J.
SNARE selectivity of the COPII coat.
Mossessova, E., Bickford, L.C., Goldberg, J.
The COPII coat buds transport vesicles from the endoplasmic reticulum that incorporate cargo and SNARE molecules. Here, we show that recognition of the ER-Golgi SNAREs Bet1, Sed5, and Sec22 occurs through three binding sites on the Sec23/24 subcomplex of yeast COPII. The A site binds to the YNNSNPF motif of Sed5. The B site binds to Lxx-L/M-E sequences present in both the Bet1 and Sed5 molecules, as well as to the DxE cargo-sorting signal. A third, spatially distinct site binds to Sec22. COPII selects the free v-SNARE form of Bet1 because the LxxLE sequence is sequestered in the four-helix bundle of the v-/t-SNARE complex. COPII favors Sed5 within the Sed5/Bos1/Sec22 t-SNARE complex because t-SNARE assembly removes autoinhibitory contacts to expose the YNNSNPF motif. The COPII coat seems to be a specific conductor of the fusogenic forms of these SNAREs, suggesting how vesicle fusion specificity may be programmed during budding.
Howard Hughes Medical Institute and the Cellular Biochemistry and Biophysics Program, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10021, USA.

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Retrieved Text: Schematic showing the cytoplasm, with major components of a typical animal cell. (1) nucleolus (2) nucleus (3) ribosome (4) vesicle (5) rough endoplasmic reticulum (6) Golgi apparatus (7) cytoskeleton (8) smooth endoplasmic reticulum (9) mitochondria (10) vacuole (11) cytosol (12) lysosome (13) centriole.
Cytoplasm is a gelatinous, semi-transparent fluid that fills most cells. Eukaryotic cells contain a nucleus that is kept separate from the cytoplasm by a double membrane layer.
The cytoplasm has three major elements; the cytosol, organelles and inclusions. The cytosol is the gooey, semi-transparent fluid in which the other cytoplasmic elements are suspended. The cytoplasm holds organelles and protects them, such as the vacuole, endoplasmic recticulum, etc. Cytosol makes up about 70% of the cell and is composed of water, salts and organic molecules. The cytoskeleton, various proteins, ribosomes and enzymes that are necessary for the cell to catalyze reactions are also found throughout the cytosol. The inner, granular and more fluid portion of the cytoplasm is referred to as endoplasm.
The cytoplasm is the site where most cellular activities are done. The functions for cell expansion, growth and replication are carried out in the cytoplasm of the cell. The cytosol has enzymes that take molecules and break them down , so that the individual organelles can use them as they need to. The cytosol also contains the cytoskeleton which gives the cell its shape and can help in the movement of the cell.
Alberts, Bruce et al. (2003). Essential Cell Biology, 2nd ed., Garland Science, 2003, ISBN 081533480X.
Human Anatomy & Physiology, seventh edition By; Elain N

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Retrieved Text: Particles move across membranes by simple diffusion, facilitated diffusion, osmosis and active transport.
U1. Particles move across membranes by simple diffusion, facilitated diffusion, osmosis and active transport.
Osmosis is the passive movement of water molecules, across a partially permeable membrane, from a region of lower solute concentration to a region of higher solute concentration.
Diffusion is the passive movement of particles from a region of high concentration to a region of low concentration.
Passive transport across membranes by simple diffusion and facilitated diffusion.
The cell membrane is hydrophobic inside thus hydrophobic (lipid soluble) molecules will pass through easily. This is by simple diffusion. However hydrophilic molecules and charged particles will not be able to cross the cell membrane. They will need the help of protein channels, this is facilitated diffusion.
Simple diffusion involves the diffusion of molecules through the phospholipid bilayer while facilitated diffusion involves the use of channel proteins embedded in the membrane.
Water moves through by osmosis which is also by passive transport. Osmosis involves the movement of water molecules from a region of low solute concentration, to a region of high solute concentration. So if the solute concentration is higher inside the cell than outside the cell, water will move in and vice versa.
Protein pumps and ATP in active transport across membranes.
When there is a passage of materials against a concentration gradient (from low to high) it is called active transport.
This process use protein pumps translocate molecules against concentration gradient by using energy from ATP.
The hydrolysis of ATP causes a conformational change in the protein pump resulting in the forced

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Retrieved Text: A lumen (Lat. lūmen, an opening or light) (pl. lumina) in biology is the inside space of a tubular structure, such as an artery or intestine. By extension, a lumen can also be the inside space of a cellular component or structure, such as the endoplasmic reticulum.
The interior of a vessel, such as the central space in an artery or vein through which blood flows.
Within a cell, the inner membrane space of a thylakoid, endoplasmic reticulum, Golgi apparatus, lysosomes, mitochondria or microtubule.
↑ Stedman's Medical Dictionary, 24th ed.
↑ Adds, John; Erica Larkcom, Ruth Miller. Exchange and transport, energy and ecosystems, Nelson Advanced science (Nelson Thornes web site).

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Retrieved Text: CHAPTER OUTLINE CELL THEORY AND DISCOVERY The cell is the smallest structural and functional unit capable of carrying out life processes. Cells are the building blocks for all multicellular organisms including humans. Cells of a hummingbird, a human, and a whale are all about the same size. Larger species have more cells, not larger cells. The human body has about 200 different types of cells based on structure and specialization. AN OVERVIEW OF CELL STRUCTURE Most of the trillions of cells making up the human body share three major subdivisions: -The plasma membrane is composed of a bilayer of phospholipids containing proteins, carbohydrates, and cholesterol and functions to provide a semipermeable barrier around the cell. The membrane functions to prevent intracellular fluid from mixing with extracellular fluid (which separates the cell’s contents from its surroundings), yet it functions to assist in the transport of life-sustaining substances into the cell and waste materials out of the cell. -The nucleus is bounded by the double-layer membrane (nuclear envelope) and contains deoxyribonucleic acid (DNA). The nucleus is the site for the synthesis of all types of RNA (transcription). The nuclear envelope is pierced by many nuclear pores that allow necessary traffic to move between the nucleus and the cytoplasm. -The cytoplasm consists of the cytosol and both membranous and non-membranous organelles. ENDOPLASMIC RETICULUM AND SEGREGATED SYNTHESIS The endoplasmic reticulum (ER) is a complex membrane system with two distinct, but connected, regions: rough (RER) and smooth endoplasmic reticulae (SER). The RER membrane is studded with ribosomes, which are the “workbenches”

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Retrieved Text: Enduring understanding 2.B: Growth, reproduction and dynamic homeostasis require that cells create and maintain internal environments that are different from their external environments.
Essential knowledge 4.A.2: The structure and function of subcellular components, and their interactions, provide essential cellular processes.
1. Rough endoplasmic reticulum functions to compartmentalize the cell, serves as mechanical support, provides site-specific protein synthesis with membrane-bound ribosomes and plays a role in intracellular transport.
2. In most cases, smooth ER synthesizes lipids.
1. Functions of the Golgi include synthesis and packaging of materials (small molecules) for transport (in vesicles), and production of lysosomes.
1. Mitochondria have a double membrane that allows compartmentalization within the mitochondria and is important to its function.
2. The outer membrane is smooth, but the inner membrane is highly convoluted, forming folds called cristae.
3. Cristae contain enzymes important to ATP production; cristae also increase the surface area for ATP production.
1. The structure and function relationship in the chloroplast allows cells to capture the energy available in sunlight and convert it to chemical bond energy via photosynthesis.
2. Chloroplasts contain chlorophylls, which are responsible for the green color of a plant and are the key light-trapping molecules in photosynthesis. There are several types of chlorophyll, but the predominant form in plants is chlorophyll a.
3. Chloroplasts have a double outer membrane that creates a compartmentalized structure, which supports its function. Within the chloroplasts are membrane-bound structures called thylakoids. Energy-capturing reactions housed in the thylakoids are organized in stacks, called “grana,” to produce ATP and NADPH2, which fuel carbon-fixing reactions in the Calvin-Benson cycle. Carbon fixation occurs in the

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Retrieved Text: Electron microscopy of the cotton fibre: new observations on cell wall formation.
The ultrastructure of the cotton fibres was examined after developing successful fixation methods. Fibre cells were fixed at different stages of development. In cells which were elongating and producing primary cell walls, the Golgi apparatus appeared to be directly involved in secretion and synthesis of primary wall components. In cells which were synthesizing thick secondary cell walls, evidence suggested a major role for the endoplasmic reticulum and plasma memebrane in the synthesis and secretion of secondary wall materials. The possibility of a shift from a Golgi apparatus pathway for primary wall synthesis to an endoplasmic reticulum pathway for secondary wall synthesis is discussed. Plasma membrane micro-invaginations are present only during secondary wall synthesis and may represent sites of cellulose assembly. A model for primary wall biogenesis via the Golgi apparatus is presented, and the potential of the cotton fibre as a model system for studying cellulose biogenesis in higher plants is discussed.
beta-1,3-Glucan in Developing Cotton Fibers: Structure, Localization, and Relationship of Synthesis to That of Secondary Wall Cellulose.

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Score: 61.568382
Retrieved Text: "The Parkinson's Disease Protein α-Synuclein Disrupts Cellular Rab Home" by Aaron D. Gitler, Brooke J. Bevis et al.
α-Synuclein (α-syn), a protein of unknown function, is the most abundant protein in Lewy bodies, the histological hallmark of Parkinson's disease (PD). In yeast α-syn inhibits endoplasmic reticulum (ER)-to-Golgi (ER→Golgi) vesicle trafficking, which is rescued by overexpression of a Rab GTPase that regulates ER→Golgi trafficking. The homologous Rab1 rescues α-syn toxicity in dopaminergic neuronal models of PD. Here we investigate this conserved feature of α-syn pathobiology. In a cell-free system with purified transport factors α-syn inhibited ER→Golgi trafficking in an α-syn dose-dependent manner. Vesicles budded efficiently from the ER, but their docking or fusion to Golgi membranes was inhibited. Thus, the in vivo trafficking problem is due to a direct effect of α-syn on the transport machinery. By ultrastructural analysis the earliest in vivo defect was an accumulation of morphologically undocked vesicles, starting near the plasma membrane and growing into massive intracellular vesicular clusters in a dose-dependent manner. By immunofluorescence/immunoelectron microscopy, these clusters were associated both with α-syn and with diverse vesicle markers, suggesting that α-syn can impair multiple trafficking steps. Other Rabs did not ameliorate α-syn toxicity in yeast, but RAB3A, which is highly expressed in neurons and localized to presynaptic termini, and RAB8A, which is localized to post-Golgi vesicles, suppressed toxicity in neuronal models of PD. Thus, α-syn causes general defects in vesicle trafficking, to which dopaminergic neurons are especially sensitive.
Gitler, Aaron D.; Bevis, Brooke J.; Shorter, James; Strathearn, Katherine E.; Hamamichi, Shusei; Su, Linhui Julie; Caldwell,

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Retrieved Text: Oxysterol-binding Protein Activation at Endoplasmic Reticulum-Golgi Contact Sites Reorganizes Phosphatidylinositol 4-Phosphate Pools.
Oxysterol-binding protein (OSBP) exchanges cholesterol and phosphatidylinositol 4-phosphate (PI-4P) at contact sites between the endoplasmic reticulum (ER) and the trans-Golgi/trans-Golgi network.
CARTS biogenesis requires VAP-lipid transfer protein complexes functioning at the endoplasmic reticulum-Golgi interface.
Vesicle-associated membrane protein-associated protein (VAP) is an endoplasmic reticulum (ER)-resident integral membrane protein that controls a nonvesicular mode of ceramide and cholesterol transfer from the ER to the Golgi complex by interacting with ceramide transfer protein and oxysterol-binding protein (OSBP), respectively.
MicroRNA124 Regulated Neurite Elongation by Targeting OSBP.
In this study, we demonstrated that miR-124 directly targeted and downregulated the endogenous expression of oxysterol-binding protein (OSBP).
Delivery of Constitutively Active Mutant MKK6(E) With TAT-OSBP Induces Apoptosis in Human Ovarian Carcinoma HO8910 Cells.
In this study, we evaluated the tumor selectivity, cellular internalization, and biological activity of a cell-permeable ovarian cancer cell-specific therapeutic protein consisting of TAT-OSBP and constitutively active MKK6(E), an upstream kinase of the p38 signaling pathway that mediates cellular apoptosis.
Modulation of the Host Lipid Landscape to Promote RNA Virus Replication: The Picornavirus Encephalomyocarditis Virus Converges on the Pathway Used by Hepatitis C Virus.
The ensuing phosphatidylinositol 4-phosphate (PI4P) proved important for the recruitment of oxysterol-binding protein (OSBP), which delivers cholesterol to EMCV ROs in a PI4P-dependent manner.
Novel mechanisms of intracellular cholesterol transport: oxysterol-binding proteins and membrane contact sites.
Sterol transfer by lipid-binding proteins, such as OSBP (oxysterol-binding protein), coupled with phosphatidylinositol 4-phosphate exchange at membrane contact sites (MCSs) has emerged as a new theme of cholesterol transport between organellar membranes.
INTRACELLULAR TRANSPORT. PI4P/phosphatidylserine countertransport at ORP5- and ORP8-mediated

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======= Instance Index 4180 =========
Input Text: Answer the following question given this paragraph: 

The immune system includes lymph organs, lymph vessels, lymph, and lymph nodes.


Q: What system includes lymph organs, lymph vessels, lymph, and lymph nodes?

 Choices:

- nervous

- immature

- immune

- digestion

A:

Target Text: immune

#### Retrieved Documents ####

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Retrieved Text: Lymph system; drawing shows the lymph vessels and lymph organs, including the lymph nodes, tonsils, thymus, spleen, and bone marrow. One inset shows the inside structure of a lymph node and the attached lymph vessels with arrows showing how the lymph (clear fluid) moves into and out of the lymph node. Another inset shows a close up of bone marrow with blood cells.

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Retrieved Text: The lymphatic system is a series of vessels and nodes that collect and filter excess tissue fluid (lymph), before returning it to the venous circulation. It forms a vital part of the body’s immune defence.
In this article, we shall look at the components of the lymphatic system, their structure and their clinical correlations.
Fig 1 – Overview of the lymphatic system. It contains lymphoid organs, vessels, nodes and lymph fluid.
There are a number of organs that contain lymphatic tissue. They are involved in blood filtering and the maturation of lymphocytes.
Spleen – Functions mainly as a blood filter, removing old red blood cells. It also plays a role in the immune response.
Thymus – Responsible for the development and maturation of T lymphocyte cells.
Red bone marrow – Responsible for maturation of immature lymphocytes, much like the thymus.
In addition, some lymphatic tissue is located in the tonsils, appendix, and in the walls of the gastrointestinal tract.
Lymph nodes are kidney shaped structures which act to filter foreign particles from the blood, and play an important role in the immune response to infection. On average, an adult has around 400 to 450 different lymph nodes spread throughout the body – with the majority located within the abdomen.
Each node contains T lymphocytes, B lymphocytes, and other immune cells. They are exposed to the fluid as it passes through the node, and can mount an immune response if they detect the presence of a pathogen. This immune response often recruits more inflammatory cells into the node – which is why lymph nodes are palpable

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Retrieved Text: When sickness or infection invades the body, the immune system is the first line of defense. A big part of that defense is the lymph system. Lymph is carried through the body by lymph vessels that have valves and muscles to help move the fluid. Along the route are lymph nodes that serve as filters for harmful substances. This network of vessels and nodes together is called the lymph system.
If the cancer cells are carried through the lymph system, either of two things could happen: 1) They may reach nearby lymph nodes - essentially, small clusters of immune cells or 2) They may spread to other organs in the body.
They can't ventilate like a runner, so that makes the lymph system less efficient.
What makes the triathlon's swim leg dangerous?
Dormant infection TB is caused by a pathogen called Mycobacterium tuberculosis, which is most commonly found in the lungs although it can spread to other parts of the body, such as the lymph system.
This kind of cancer spreads to the lymph nodes and other parts of the body through the lymph system and bloodstream.
Previous research by the same study authors confirmed that the same beers also reduced the formation of harmful chemicals called polycyclic aromatic hydrocarbons (PAHs), which have been directly linked to DNA damage and the development of tumors in cells of the colon, breast, prostate and lymph system.
When cancer cells break away from a tumor, they can travel to other areas of the body through either the bloodstream or the lymph system.
The lymph system helps maintain

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Retrieved Text: Peyer's patches are clusters of lymphoid tissue found primarily in the large intestine.
Lymph always flows away from the heart.
If even a small part of the spleen is left in a ten-year-old child, it will most likely regenerate itself.
Small organs associated with lymphatic vessels are termed ________.
Which of the following would not be classified as a lymphatic structure?
The distal portion of the small intestine contains clumps of lymph follicles called ________.
Both lymph and venous blood flow are heavily dependent on ________.
The thymus is most active during ________.
Which lymphatic structure drains lymph from the right upper limb and the right side of the head and thorax?
What effect does age have on the size of the thymus?
The lymphatic capillaries are ________.
Antibodies that act against a particular foreign substance are released by ________.
Lymph leaves a lymph node via ________.
Functions of the spleen include all of those below except ________.
When the lymphatics are blocked due to tumors, the result is ________.
B cells produce plasma cells, which secrete antibodies into the blood.
A ring of lymphoid tissue that appears as a swelling of the mucosa in the oral cavity is called a(n) ________.
Which is not a mucosa-associated lymphatic tissue?
Peyer's patches are found in the ________.
Lymph collecting or pooling from the lower extremities would first pool in the ________ before moving on up.
It has no known significant function.
Particularly large clusters of lymph nodes occur in all of the following locations except the ________.
Digestive tract-associated lymphatic tissue includes all of the following except ________.
Functions of the lymphatic system include ________.
The tonsils located at the base

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Retrieved Text: The first thing to understand about your lymph system is its size. Like the circulatory system that supplies blood, the network of lymph vessels serves almost every cell in your body.
The lymphatic system is composed of a vascular network of thin-walled capillaries that drain protein-rich lymph from the extracellular spaces within most organs. A continuous single-cell layer of overlapping endothelial cells lines the lymphatic capillaries, which lack a continuous basement membrane and are, therefore, highly permeable. Lymph returns to venous circulation via the larger lymphatic collecting vessels, which contain a muscular and adventitial layer, and the thoracic duct. The lymphatic system also includes lymphoid organs such as the lymph nodes, tonsils, Peyer’s patches, spleen, and thymus, all of which play an important role in the immune response.
The lymphatic system develops in parallel with the blood vascular system through a process known as lymphangiogenesis, and lymphatic vessels are not normally present in avascular structures such as epidermis, hair, nails, cartilage, and cornea, nor in some vascularised organs such as brain and retina. Although studies of normal development and pathologic growth of the blood vascular system have thoroughly elucidated the molecular mechanisms that control these angiogenic processes studies of the lymphatic system have been hindered by the lack of specific lymphatic markers and growth factors. Consequently, the understanding of the development and function of the lymphatic system and its role in disease is still emerging.
The largest concentration of lymph tissue in the body surrounds the intestines. Called gut-associated lymphatic tissue, or GALT, this tissue is the guardian of

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Retrieved Text: 10% of its fluid escape into the surrounding tissues, as blood proceeds through the capillaries and is known as tissue fluid. Chemicals such as glucose and hormones is carried by this fluid to the cells of the body that are not next to the capillary.It then removes the waste products like as urea and CO2. The overall effect is to ensure that the tissue fluid is constantly on the move and so every cell in the body receives a fresh supply of nutrients.
Not all of the fluid forced out of the capillaries is returned by osmosis and a network of vessels known as the lymphatic system collects this excess fluid and returns it to the circulatory system. This system is known as lymphatic system.
Lymph is colourless liquid connective tissue. It is blood less RBCs, platelets and some plasma proteins.
The lymphatic system has no pump, so lymph must be moved through vessels by the squeezing of skeletal muscles.
Lymph passes through thin walled lymph capillaries present in the tissue spaces. Each lymph capillary is lined by endothelium of thin and flat cells. They are interwoven with blood vessels but are not connected to them. They are blind at one end and wider than blood capillaries. These lymph vessels join together to form wider lymphatic vessels.
The two main lymphatic vessel are thoracic or left lymphatic duct and right lymphatic duct. Thoracic duct is main collecting duct of lymphatic system. It collects lymph from left side of head, neck, chest left upper extremity and entire body below the ribs. The

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Retrieved Text: Why the role of the lymphatic system is so important for your health? How to support its better functioning incorporating some useful habits in your lifestyle? What not to do if you want to have a lymphatic system that works properly?
The lymphatic system is the body’s drainage net of small tubes that takes away the excessive fluid, called lymph, leaked from the blood vessels in the tissues and brings it back to the bloodstream through the lymph nodes. Another function of this system is its role in the immune defence of the organism against bacteria, fungus, waste products, toxins and any other dangerous substances and cells that may be found in the body. The lymphatic nodes and the organs connected to this system like the spleen and the thymus store white cells which are rapidly multiplied and released in the blood if any bacteria, virus or dying cells are detected.
If any disorders occur in the lymphatic system the overall health would be affected immediately, the lymph needs to move easily in the body, so the waste materials of any kind to be able to leave the organism. The lymphatic vessels doesn’t have their own pressure like the blood vessels and the lymph is moving upwards always. So, what can you do daily to support its work?
As soon as the lymph is not able to move on its own because of the lack of pressure in the lymphatic vessels, the only way to support its movement is through exercises and contraction of the muscles. The sitting or

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Retrieved Text: The lymphatic system works with other parts of your immune system to help your body fight infection and disease. It is made up of a network of lymph vessels, lymph nodes and the lymphatic organs. Lymph vessels carry lymph fluid, which contains lymphocytes and other white blood cells, antibodies and nutrients. Lymph nodes sit along the lymph vessels and filter lymph fluid. The lymphatic organs include the spleen, thymus, tonsils, adenoids and bone marrow.
B cells stay in the bone marrow until they mature.
T cells move to the thymus to mature.
Rare types of NHL can also develop. Post-transplant lymphoproliferative disease (PTLD) is a rare form of NHL that may occur after a solid organ transplant. Follicular NHL and marginal zone B-cell lymphoma are extremely rare in childhood.
The different types of NHL look different under a microscope. They also develop and grow differently. Most types of childhood NHL are high grade because they grow and spread quickly. Your child’s doctor will find out the type of NHL to make sure your child gets the treatment that works best for that type.
Because lymphocytes are found throughout the lymphatic system, childhood NHL can start almost anywhere in the body. It usually starts in a group of lymph nodes in one part of the body, such as in the neck, above the collarbone, or in the chest, abdomen or groin. Children may also have large spleens when they are diagnosed. Childhood NHL doesn’t spread in a predictable way. It can spread through the lymphatic system or the blood to almost any

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Retrieved Text: Lymph Nodes - want to learn more about it?
Lymphoid tissues are collections of lymphocytes strategically located at potential sites of infection. They can be classified as either primary lymphoid organs (bone marrow and thymus) where de novo synthesis and maturation of lymphocytes occur; or secondary lymphoid organs where activation of lymphocytes occur. Lymph nodes are secondary lymphoid organs widely distributed throughout the body.
They are strategically located at areas that are open to foreign microorganisms (e.g. the oral cavity). For the sake of completeness, other secondary lymphoid organs include (but are not limited to) the spleen, mucosa-associated lymphoid tissue (MALT), tonsils, and Peyer’s patches. The average young adult has about 450 lymph nodes throughout the body; most of which are in the abdominopelvic region, then the thorax and the remainder in the head and neck.
This article will focus on the anatomy and histology of lymph nodes, their various locations and clinically relevant points.
Lymph nodes are bean-shaped structures about 0.1 – 2.5 cm in length. The node is enclosed in a capsule and has an indentation on one surface (along one of its long axes) known as the hilum. The hilum is the point at which arteries carrying nutrients and lymphocytes enter the lymph node and veins leave it. Afferent lymphatic vessels enter the lymph node through the capsule peripherally and efferent lymphatic vessels leave the node via the hilum. The former takes lymph from peripheral sites to the node, while the latter takes processed lymph from the nodes back to the venous circulation.
A horizontal section through the

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Rank: 9
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Retrieved Text: Tumor cells use fatty acid rather than glucose as a fuel. The metabolic adaptation yields an insight into a novel platform for treating metastasis.
The spread of cancer to a new part of the body accounts for about 90 % of cancer death. Cancer cells can spread from its birthplace to other parts of the body through either blood vessels (blood-borne metastasis) or lymphatic system (LN metastasis). By invading surrounding lymph vessels, cancer cells migrate to adjacent lymph nodes and become a colonized tumor, leading their way to other organs. If they adapt and grow in lymph nodes, the cancer cells can easily reach other organs, resulting in a worse outlook for patient’s survival. Medical oncologist Dr. Choong-kun Lee, cancer biologist Dr. Gou Young Koh, and their colleagues at the Center for Vascular Research within the Institute for Basic Science (IBS) and Korea Advanced Institute of Science and Technology (KAIST) in Daejeon, South Korea revealed a mechanism to suppress the growth and spread of cancer cells in lymph nodes, forestalling any chance for them to invade new territories of the body.
The researchers used animal models with melanoma and breast cancer, which are considered to be most likely to spread first to lymph nodes. With the comparison of cancer cells grown in lymph nodes with those grown in primary site, researchers found that the metastatic cancer cells in lymph nodes boost the expression of the genes related to fatty acids broken down to produce energy, known as fatty acid oxidation (FAO). In the meantime, the cancer cells growing

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Rank: 10
Score: 90.665474
Retrieved Text: Definition: tissues and organs, including bone marrow, spleen, thymus, and lymph nodes, that produce, store, and carry white blood cells to fight infection and disease.
Definition: The system of vessels, glands (lymph nodes), and other lymphatic tissues (like the spleen) which collects, filters (at the lymph nodes), and transports lymphatic fluid from around the tissues and eventually puts it back into the blood circulatory system. Included in the fluid it picks up is the fluid that flows out of the capillaries during normal capillary functions.

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Retrieved Text: Axillary lymph nodes are the lymph nodes located in the armpits. They can become enlarged in many conditions including infections, lymphomas, and breast cancers, Lymph nodes are small structures located all over the body around blood vessels that act as filters and can accumulate germs or cancer cells. They are a part of the lymph system of the body.
Also Known As: Armpit nodes. The medical term for armpits is axilla.
What Do the Axillary Lymph Nodes Do?
There are about 30 axillary lymph nodes (anywhere from 20 to 40) in your underarm area. The lymph fluid draining from your breast, upper abdomen, arm and neck pass through these bean-shaped nodes on its way to returning to your blood circulatory system. Lymph is a clear fluid that is produced by blood nourishes your cells and tissues. It is eventually returned to your circulatory system to make up your blood plasma. Lymph includes white blood cells but not red blood cells.
Bacteria that are loose in the body can collect in the lymph and be taken to the lymph nodes. The white blood cells that live in the lymph nodes attack bacteria and multiply to fight off an infection. They also become stimulated to produce antibodies and immune reactions to foreign germs and substances they encounter in the lymph nodes.
Metastatic cancer cells can also travel through the lymph and into the lymph nodes. This is seen in breast cancer, where the cancerous cells may spread to the axillary lymph nodes. Lymphoma is a cancer of the lymph system. It can affect

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Rank: 12
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Retrieved Text: Breast cancer oncologist and health economist Dr. Gary Lyman said there is „absolutely no reason“ why the Centers for Medicare & Medicaid Services should not cover the cost of compression sleeves for patients diagnosed with lymphedema.
SCCA physical therapist Carol Baltaxe said if patients don’t have compression, the lymphedema will „slowly get worse over time.“ Baltaxe and her colleagues try to connect patients whose insurance doesn’t cover compression garments with additional resources. Patients can also get assistance through the National Lymphedema Network.
Kategorien: Behandlung/ Therapy approach, Cancer/Krebs, Wissenschaft/Science | Permanentlink.
When cancer cells break away from the main tumor, there’s a great possibility that they will become stuck to nearby lymph nodes. This is why doctors usually check the lymph nodes first when figuring out how far cancer has grown or spread.
When the cancerous cells make contact with the lymph node, they may divide and perform a tumor at the site of the lymph node. When doctors examine the lymph nodes and find evidence of metastases (especially in lymph nodes near the primary tumor), this is an indicator that metastasis exists in distant organs and often helps doctors make prognoses.
Proper lymph drainage lowers your risk of developing cancer, as it ensures proper removal of abnormal, cancerous cells and prevents metastasis.
The Key Takeaway: When cancer cells break away from the main tumor, they can travel through other parts of the body via the lymph system. When transported via the lymph system, cancerous cells may end up in your lymph nodes, where most are killed but one or two may settle

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Retrieved Text: The lymphatic system is a quiet system that works to keep us healthy. It is composed of lymph vessels, lymph nodes, and organs. The primary function of lymph nodes is to filter and purify. As part of the body’s defense system, the lymph nodes remove microorganisms and other foreign substances. By acting like a filtration system, the lymph nodes help prevent toxic materials like bacteria, from entering the blood. Rich lymphatic networks are highly amenable to the light touch of lymph drainage massage therapy. More and more, the lymphatic system is recognized in the medical community as a way to improve our overall health and well-being.
Why does lymphatic circulation slow down?
The lymphatic flow can slow for many reasons, such as swelling, chronic inflammation, lack of physical activity, stress, fatigue, emotional shock, age, poorly fitted bras, or bras worn for too long. When lymphatic circulation slows down, the regeneration of cells becomes less effective. This condition allows toxins and proteins to accumulate around the cells, causing cellular oxygenation to decrease and tissue regeneration to diminish.
As mentioned, a common result following breast cancer treatment is a compromised lymphatic system. “Lymphedema” is the result of a failure in the lymph drainage system and can occur after lymph nodes have been removed or damaged. Fluid retention occurs and is often accompanied by painful swelling.
Lymphatic Drainage Massage is the manual manipulation of the lymphatic ducts using gentle, rhythmic massaging of the skin to stimulate the flow of lymph and its return to the blood circulation system. The treatment is very gentle,

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Score: 89.319244
Retrieved Text: MLD is a massage technique which uses a gentle pumping action.
MLD is the most relaxing massage you will ever have because of its direct effects on the nerve cells.
MLD activates the lymphatic system.
The lymph system is a major component of the body’s immune system.
It is a network of organs (spleen, thymus, tonsils and adenoids) and lymph nodes (small bean shaped nodules), ducts, and vessels that transports lymph from tissues to the bloodstream.
The nodes are where immune cells such as lymphocytes, monocytes and plasma cells are produced.
When bacteria are recognized in the lymph fluid, the lymph nodes enlarge, producing additional white blood cells to help fight infection.
When people refer to swollen glands in the neck, they are usually referring to swollen lymph nodes.
Lymph nodes also filter the lymph fluid removing foreign material such as bacteria, proteins, fats, toxins, pollutants and cancer cells.
Common areas where lymph nodes can be easily felt, especially if they are enlarged, are: the groin, armpits (axilla), above the clavicle (supraclavicular), in the neck (cervical), and the back of the head just above hairline (occipital).
Helps to maintain a healthy environment for the cells of the connective tissue to produce elastin and collagen and enables the tissue to repair and heal itself.
Injury or surgery – speeds recovery time and enables the individual to regain full range of joint motion much quicker.
Arthritis, rheumatism, migraines, intestinal disorders, constipation, sinusitis.
Ideal treatment during detox and cleanses.
Ideal treatment if having a laser fat reduction.
How often are treatments recommended?
For injury or post surgery – 1 to 2 times a week.
Other conditions

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Score: 89.18821
Retrieved Text: Manual lymphatic drainage (MLD) is a type of gentle massage which encourages the natural drainage of fluid (lymph), which carries waste products and excess fluid away from the tissues back toward the heart to be returned to the circulation and drained from the body. The lymph system depends on intrinsic contractions of the smooth muscle cells in the walls of lymph vessels and the movement of muscles to propel lymph through the vessels to the lymph nodes and then beyond the lymph nodes to the lymph ducts which return lymph to the cardiovascular system. Manual lymph drainage uses a specific amount of pressure (less than 9 ounces per square inch or about 4 kPa – Very Gentle) and rhythmic circular movements to stimulate lymph flow. This massage is generally slow and lasts 1 to 1.5 hours.
This type of massage also concentrates on the lymph nodes to encourage their drainage. It is typically used where surgery has disrupted the lymph system (vessels, nodes, ducts) and excess fluid is built up (lyphoedema). It can also be used in acute conditions where excessive swelling is present (i.e. orthopaedic surgery).

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Retrieved Text: Lymphatic system is essentially a drainage system which is accessory to the venous system. Most of the tissue fluid formed at the arterial end of capillaries is absorbed back into the blood by the venous ends of the capillaries and the postcapillary venules. The rest of the tissue fluid (10-20%) is absorbed by the lymphatics which begin blindly in the tissue spaces.
It is important to know that the larger particles (proteins and particulate matter) can be removed from the tissue fluid only by the lymphatics. Therefore, the lymphatic system may be regarded as ‘drainage system of coarse type’ and the venous system as ‘drainage system of fine type’.
Certain parts of the lymphatic system (lympho-reticular organs), however, arc chiefly involved in phagocytosis, raising immune responses. and contributing to cell populations of the blood and lymph. The tissue fluid flowing in the lymphatics is called lymph. It passes through filters (lymph nodes) placed in the course of lymphatics, and finally drains into the venous blood. Lymph from most of the tissues is clear and colorless, but the lymph from small intestine is milky-white due to absorption of fat. The intestinal milky lymph is called chyle, and lymph vessels, the lacteals.
For information on Gross anatomy of the lymphatic system of human body, visit the page: Lymphatic System.
The lymph capillaries begin blindly in the tissue spaces and form intricate networks. Their calibre is greater and less regular than that of blood capillaries, and their endothelial wall is permeable to substances of much greater molecular size.
Lymph capillaries are absent from the

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Score: 88.71244
Retrieved Text: What is the Lymphatic System ?
The lymphatic system belongs to the circulatory apparatus, which provides one way for the blood to leave the heart, the arterial system, and two ways for it to return : the venous and lymphatic pathway. The lymphatic system is a second pathway back to the heart, parallel to the blood system.
Lymph is a fluid which originates in the connective tissue spaces of the body. Once it has entered the first lymph capillaries, the fluid is called lymph. The lymphatic circulation is a system with slow rhythm, low velocity and low pressure.
Part of the constituents of the blood will filter out of the blood capillaries. This blood capillary filtrate will join the surrounding tissues and to be reabsorbed in the lymphatic capillaries.
The lymphatic system fine tunes the drainage of the interstitium and constitutes a sort of overflow for the water and excess substances in the interstitial environment.
The lymphatics gradually increase in size : lymph capillaries feed into pre-collectors which connect to the lymphatic collectors, ducks and trunks and eventually join the major venous circulation just before reaching the heart behind the clavicles.
The lymphatic system transports large proteins and foreign bodies to lymphatic nodes which act as active purification centres. The nodes break down and destroy those particles so they can eventually be flushed out of the body through the organs of elimination.
Manual Lymph Drainage (MLD) is not a form of massage but it is a very gentle technique to detect the specific rhythm, direction, depth and quality of the lymph flow and

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Rank: 18
Score: 87.9655
Retrieved Text: Your lymph system is a complex and little-thought-of drainage system in the body. This system is mostly ignored, of course, until someone gets cancer. The entire system contains vital organs including the spleen, the thymus, lymph nodes, and blood vessels. Your lymph system plays an extremely important role when it comes to fighting infection, and removing fats, toxic waste, and excess fluid from the body. A deficiency in iodine, digestive problems, lack of exercise, and illnesses can all clog the lymph system, keeping it from doing its vital job.
But what can you do to keep this system from becoming clogged, trapping toxins and other waste, including excess fluids, inside the body? There are plenty of natural ways to keep your lymph system clean and free flowing. Doing so has many benefits as well including improving your skin tone, relieving recurring sinus infections, headaches, arthritis, fatigue, lowering cholesterol levels, improved energy levels, an improved immune system, and a general improvement in overall health.
Keep reading and find out the top ways you can keep your body’s drainage system in tip top shape. It’s easier than you think!
Eating a healthy diet is perhaps one of the best ways to avoid a sluggish lymph system. Adding the following foods will go a long way towards keeping your lymphatic system healthy and clear.
The more raw, organic vegetables and fruits you can add to your diet, the healthier your lymph system will be.

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Retrieved Text: Manual Lymphatic drainage is a type of a gentle massage which is intended to encourage the natural drainage of lymph, which carries waste products away from the tissues back toward the heart. The lymph system depends on intrinsic contractions of the smooth muscle cells in the walls of lymph vessels and the movement of skeletal muscles to propel lymph through the vessels to the lymph nodes and then beyond the lymph nodes to the lymph ducts which return lymph to the cardiovascular system. Manual lyphh drainage uses a specific amount of pressure and rhythmic circular movements to stimulate lymph flow.
We will work with your doctor and physical therapist to get you the best care needed. We customize all of our massages to your specific needs as Lymphatic massage is different for everyone.

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Retrieved Text: Lymph nodes in the human body playimportant role. They act as biological filters and are organs of the immune system. It is the lymph nodes that detain the infection and prevent its spread throughout the body. At the same time, not everyone knows where these organs are. In this article, let's talk about where the lymph nodes are on the neck.
When a person is healthy, then feel the lymph nodesneed more carefully. They have the shape of balls, which have mobility. To detect them, it is necessary to start probing the area located under the jawbone and further down to the end of the neck.
Determine where the lymph nodes are located in the neck inthe period of the disease, accompanied by their inflammation, is not difficult. After all, they increase in size and are easily felt on the neck, which often causes soreness.
You should know that the lymph nodes are not onlyon the neck, but also in the groin. Determine exactly where they are located in this area is quite simple. They are slightly above the pubic part, namely on the sides of it. In fact, they are located between the leg and groin. In size, such nodes are similar to peas of large sizes. When they are inflamed, they are visible to the naked eye, and when probed cause pain. They are provoked by an increase in various venereal diseases, which are easy to identify with the help of a number of analyzes.
In any case, having found themselves inflamedlymph nodes in the neck or in

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Retrieved Text: Lymphatic System Questions including "Can wisdom teeth cause enlarged lymph nodes or an enlarged spleen"
This category is for questions about the various vessels by which lymph, a watery fluid of leukocytes, circulates through the body, providing transportation for some materials and removing particulate from tissues.
Where are the supratrochlear lymph nodes located?
What is the fluid and particles absorbed into lymph capillaries?
The vast majority of the bodys lymph is drained by the?
Does lymph fluid contain erythrocytes?
Your lymph nodes in your groin under your arms and in your neck and back of neck are all enlarged not enormous but swollen a bit you have had a cbc that came back normal Is HIV the only other thing?
Composition and functions of lymph?
Does cold effect lymph flow?
What is the function of the lymphatics system?
What are monocytes and lymphocytes?
Why doesn't your immune system attack your own cells?
They have the same genetic structure as the rest of your body, it will only target foreign cells.
What does the immune system normally do?
How does the HIV virus damages the immune system?
What type of leukocyte would increase rapidly during allergy attacks?
How lymphatic organs fight infection?
Large phagocytic white cells that spend most of their time outside the blood as fixed and free phagocytic cells?
Does HIV weakin the immune system right away?
What are the after Effects of dengue followed by swine flu on immune system?
What body system includes lymph nodes?
They are included in two human body systems: The Lymphatic System and the Immune System.
What disease in horses cause swelling of the lymph nodes and nasal discharge?
Does alcohol lower

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Retrieved Text: B-cell —Makes antibodies that help the body identify foreign substances in the body. The sooner the substance is identified the sooner the immune system can work on eliminating it.
T-cell —T-cells have a number of jobs including destroying invading bacteria and viruses, or stimulating or slowing an immune response.
Lymph fluid —Clear fluid made up of plasma (a blood component that comes from general circulation), lymphocytes, cellular by-products, and proteins.
Lymph vessels —Fluid from spaces between the cells and other bodily structures is collected by lymph capillaries (microscopic vessels) and moved into larger lymph vessels. Lymph is moved toward the heart by lymphatic and muscular contractions. The lymph is filtered through lymph nodes and eventually returned to the blood supply by draining into large veins near the collarbone.
Lymph nodes —Lymphoid tissue that contains lymphocytes and other immune system cells. Lymph nodes are scattered throughout the body in clusters. Lymph vessels pass through lymph nodes. As lymph passes through, it is filtered for foreign bodies, including cancer cells. Lymph nodes can become swollen or painful when the body is fighting an infection.
Bone marrow —All blood cells start as stem cells and are formed in bone marrow. Stem cells can mature into a variety of different blood cell types that have specific functions in the body.
Spleen —Located under the rib cage on the left side of the body. The spleen helps the body fight infection by making lymphocytes and other immune system cells. It filters out cellular by-products from circulation. The spleen also removes and destroys old, damaged red blood cells.
Thymus

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Retrieved Text: This page is being re-written and restructured.
On L-W-O we encourage our members to become their own advocates or "expert patient" although the latter will require a degree of diplomacy. The more you learn on how to self-manage your condition the easier it will become to live with lymphoedema. Self-management however, can be daunting and I prefer to think of it as self-care. It starts with you learning to understand your condition and, on this page, I will explain in simple terms as much as I can about the lymphatic system, but I ask the reader to bear in mind I am not a medical person but someone who lives with secondary lymphoedema.
Learning how to manage lymphoedema or taking care of yourself is a major part of treatment. At first it may seem overwhelming and feel unfair they you have all this to deal with. It is normal to have these difficult feelings from time to time.
Your lymphoedema specialist will explain, and show you, what you can do to help yourself.
Gradually you'll find that you can develop a routine that builds lymphoedema self-care into your everyday activities.
Family and friends often want to help and there are many practical things they can do, such as heavy lifting or carrying, helping you with your compression garment, or massage.
Primary lymphoedema - that developed at birth or shortly after puberty and is caused by faulty genes or missing genes.
Secondary lymphoedema - caused by damage to the lymphatic system as a result of an infection, injury, trauma or cancer.
Lymph fluids flows through

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Retrieved Text: If you would like to set an appt, please Call or Text me at 614-431-8814 and share a couple times that will work for you. I'll be glad to get back to you as soon as I can!
Ever feel like your immune system is working overtime? If so, you might want to give it some help by working with a massage therapist or skin care professional trained in manual lymph drainage. This mysterious sounding name refers to a technique that was invented in Europe and is widely used there. The treatment can not only boost your immunity, it can help the body detox, move congestion out of the body, and reduce swelling, especially after surgery.
The lymphatic system supports the body's immunity function and involves several organs (adenoids, thymus, tonsils, spleen), hundreds of lymph nodes, and a network of vessels. A clear fluid called lymph flows through these vessels and filters metabolic waste through the lymph nodes. These wastes include bacteria, dead cells, fats, fluids, proteins, and viruses.
When a trained therapist gently stimulates lymph nodes, it helps correct swelling and stagnation in the nodes, boosts the immune system, reduces local fluid retention, and provides relaxation. Giving this treatment requires advanced training and is practiced with a very specific set of light, massage-like strokes.
These strokes are light, and there should be no discomfort. You may feel you are hardly being treated at all, but lymphatic drainage goes a long way in terms of the benefits you may gain.
After your lymph drainage treatment, it's important to drink plenty of

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Retrieved Text: Unless one comes down with an illness or an infection that results in swelling of the lymph nodes, one is unlikely to be aware of the importance of the daily functions of the lymphatic system. Would it surprise you to know that the lymphatic system provides support for the immune, digestive, detoxification and nervous systems, and plays a major role in illness prevention and injury recovery? Similar to the way our circulatory system moves oxygen and nutrient rich blood throughout the body, the lymphatic system’s extensive network of vessels carries lymph fluid, largely composed of mineral-rich water, proteins and infection-fighting specialized white blood cells, to our cells, tissues and organs and carries away toxins, dead cells and waste materials.
The heart, as part of the circulatory system, pumps blood throughout the body and returns it to the lungs, where blood is re-oxygenated and carbon dioxide is expelled. Dissimilar to the circulatory systems, lymphatic vessels carry fluid in one direction only, away from the tissues and towards the heart. Amazingly, the lymphatic system moves fluid throughout the body without active pumping, relying on the movement of our muscles and the action of lymph vessel walls and valves to control the movement of the lymph fluid. Vessels connect the lymphatic system, which consists of hundreds of lymph nodes, the bone marrow and the lymphatic organs–the tonsils, thymus and spleen.
The lymph nodes generate and store white blood cells and function as filters, cleansing the fluid of debris. The tonsils play a defensive role against bacteria and pathogens entering the body

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Retrieved Text: The lymph system plays a crucial part in detoxification and defense. About two liters of lymph fluid circulate in our lymphatic vessels that cover the body from the tips of the toes to the top of the head.
These two liters are formed continually from the interstitial fluid that is the extra cellular fluid surrounding each one of our body cells. This extra cellular fluid penetrates the membrane of the capillaries (the thinnest vessels), to keep the volume of lymph fluid constant and to allow the waste products to leave the cells and be carried away to the venous blood stream and evacuated.
The capillaries of the lymph and the capillaries of the venous blood work together, and one compensates for the deficiencies of the other. The network of lymphatic capillaries leads to bigger lymphatic vessels and finally to the lymphatic glands. They are placed in groups all along the lymphatic ways.
Their tasks are manifold, but always aiming at the defense of the body and purification of the body fluids to maintain its proper functioning. These lymphatic glands are stations where infectious agents are filtered and lymphocytes (white blood cells, “the police”) are produced.
Other sites of lymphocyte production are the spleen, the thymus, etc. If infectious agents intrude into the body, the production of white blood cells increases rapidly and proportionally to the intensity of the aggression. The lymph nodes that are closest to the site react first: they swell, get warm and hurt.
If the production of lymphocytes is insufficient, the body’s defense against invaders and against cancer

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Retrieved Text: Lymph node removal, known as medical lymphadectomy, is used to clarify unclear lymph node swellings. If a patient has cancer, suspicious lymph nodes are removed to stop it from spreading.
Lymph nodes are part of the immune system and therefore play an important role in the prevention of viruses and bacteria. They filter the lymph fluid and are thus often the first place where metastases from tumour cells spread.
Lymph nodes are therefore removed for diagnostic and therapeutic purposes. Diagnostic lymph node removal is used to determine the cause of unclear lymph node swellings. If a patient is diagnosed with cancer, the lymph nodes which are closest to the tumour (sentinel lymph nodes) are checked for cancer metastases. Therapeutic lymph node removal is used when the lymph nodes already contain metastases or to prevent the metastisation in the lymph nodes.
Typical places where lymph nodes are removed are: the armpits in the case of breast cancer, the groin area in the case of cancers of the pelvic organs, the neck in the case of tumours in the head, neck area.
What preparations are carried out before the procedure?
Different clarifications are undertaken before the lymph nodes are removed. Blood tests provide evidence of an infection or possible cancer. Suspicious lymph nodes are precisely localised with an ultrasound or with other examinations. Sometimes the lymph nodes are initially punctured before the removal.
The operation is usually performed on an outpatient basis. Surface lymph nodes in the neck, in the armpits or in the groin area can usually be removed under local anaesthesia. Deep-rooted

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Retrieved Text: What should I know about swollen lymph nodes (glands)?
What are lymph nodes? What do they do?
Where are the lymph nodes located in the body (pictures)?
Are swollen lymph nodes painful?
How do you check for swollen lymph nodes?
What infections and viruses cause swollen lymph nodes?
What bacteria, parasites, and fungi cause swollen lymph nodes?
When should I see the doctor for swollen lymph nodes?
What are treatments and remedies for swollen lymph nodes?
How long does it take swollen lymph nodes to resolve (go away )?
What are the complications of swollen lymph nodes?
Lymph nodes are located throughout the body but are visible and able to be felt (palpable) only when they are enlarged or swollen.
Doctors and other health care professionals check these areas for enlarged or swollen lymph nodes.
A wide variety infections are the most common causes of swelling of the lymph nodes, for example, strep throat, ear infections, and mononucleosis. More serious medical problems such as HIV infection, lymphomas (non-Hodgkin’s lymphoma) or other cancers, or lupus may cause swollen lymph glands.
Rarely, a medication can cause the problem.
Symptoms associated with lymph node swelling and related diseases can include pain in the area of the swelling, fever, and fatigue.
Swollen lymph glands are typically a result of local or widespread inflammation, but sometimes enlarged lymph nodes are due to cancer.
Lymph nodes are an important part of the body's immune system and to help fight infections. Swollen lymph nodes usually caused by infection are referred to as lymphadenitis.
Lymph is a watery fluid that circulates within the lymphatic vessels. Lymph nodes are found near these vessels.
Within

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Retrieved Text: Until now, no one knew that lymphatic vessels existed in the brain. That is why the announcement from the University of Virginia School of Medicine is stunning! People in Professor Kipris’ lab have found that there are indeed lymphatic vessels. This is the missing link between the brain and the immune system. This means that the brain is connected directly to the immune system. The true significance of this discovery lies in the effect it will have on the treatment of neurological diseases. In the article below, they only talk about neurological diseases, such as Alzheimer’s, multiple sclerosis, and autism. I would add mental illness to those illnesses above. After all mental illness is also a neurological disease. There are many immune symptoms associated with mental illness. People who have mental illness also, many times, have auto immune diseases like lupus, rheumatoid arthritis, Hashimoto’s thyroiditis. There is some sort of an immune component in mental illness. The finding of these lymph vessels directly in the brain may shed light on not only neurological illnesses, but mental illnesses as well. Amazing that it took this long to discover such an important discovery as the brain has lymph vessels.
The brain actually has it’s own immune cells, the microglia, which are the resident macrophages of the brain (they clean up cellular debris if there is a brain injury or illness) and astrorocytes which secrete neutrotrophic factors after a brain injury to help neurons grow and recover and survive.
The lymphatic system is a network of tissues and organs made up

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Input Text: Answer the following question given this paragraph: 

The DNA double helix. The two sides are the sugar-phosphate backbones, composed of alternating phosphate groups and deoxyribose sugars. The nitrogenous bases face the center of the double helix. As the base-pairing rules tell us, A always pairs with T, and G always pairs with C.


Q: Which structure includes sugar-phosphate "backbones", composed of alternating phosphate groups and deoxyribose sugars, and nitrogenous bases?

 Choices:

- mulecular triplex

- dna triple helix

- dna double helix

- molecule double helix

A:

Target Text: dna double helix

#### Retrieved Documents ####

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Score: 96.37957
Retrieved Text: Nucleic acids, such as deoxyribonucleic acid (DNA) and ribonucleic acid (RNA), are composed of smaller subunits called nucleotides. They have a sugar-phosphate backbone and can be single or double stranded. A nucleotide is an organic compound composed of three parts: a sugar (either ribose or deoxyribose), at least one phosphate group, and a nitrogen-containing base. The base can have a single- or double-ring structure. Nucleotides have many functions. In addition to acting as the building blocks for nucleic acids, nucleotides can act as energy carriers, as coenzymes, and as chemical messengers.
All nucleotides are composed of three parts: a sugar (either ribose or deoxyribose), at least one phosphate group, and a nitrogen-containing base.
DNA is a double-stranded molecule that consists of four types of nucleotides: adenine, thymine, guanine, and cytosine. RNA is usually single stranded and also consists of four types of nucleotides. Deoxyribose is different from the ribose sugar in RNA, as the 2′ hydroxyl group is replaced with a hydrogen. Unlike DNA, RNA contains the nitrogenous base uracil, in place of thymine. Like protein synthesis, the process of DNA and RNA synthesis from nucleotides occurs via a series of condensation reactions. Several nucleotides bond together through the formation of phosphate ester linkages. This happens when the hydroxyl group of a phosphate from one nucleotide participates in a condensation reaction with the hydroxyl group on the carbohydrate ring from a different nucleotide. As this reaction proceeds, nucleotides link together, forming a nucleic acid molecule. In terms of structure, the 5′ and 3′ end of carbons attached to

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Retrieved Text: DNA is a nucleic acid. Nucleic acids are biological macromolecules containing oxygen, hydrogen, carbon, nitrogen and phosphorus. There are two types of nucleic acids: ribonucleic acid (RNA) and deoxyribonucleic acid (DNA). Nucleic acids are made up of basic units called nucleotides, which bind together with covalent bonds to form a polynucleotide or the nucleic acid.
A nucleotide is made up of three parts: a five-carbon sugar (deoxyribose in the case of nucleotides in DNA), a phosphate group connected with a covalent bond to the sugar’s fifth carbon atom, and one of four possible nitrogen-containing bases connected with a covalent bond to the sugar’s first carbon atom. The nitrogen base may be one of the single-ring pyrimidine derivatives thymine (T) or cytosine (C), or one of the double ring purine derivatives adenine (A) or guanine (G).
When the nucleotides are linked together in a strand of DNA, the phosphate group attached to the 5′ (pronounced ‘five prime’) carbon of the deoxyribose sugar of one nucleotide becomes joined to the 3′ carbon on the sugar of an adjacent nucleotide. The strand in which the sugar alternates with phosphate is called a sugar-phosphate backbone. The backbone is not symmetrical. It has a definite orientation, with a free 3` hydroxyl group at one end and a free 5` phosphate group at the other end. The purine and pyrimidine bases stick out to one side of the sugar-phosphate backbone.
In each DNA molecule, the number of nucleotides containing adenine (A) equals the number containing thymine (T), and the number containing guanine (G) equals the

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Retrieved Text: Deoxyribonucleic acid (/diˈɒksiˌraɪboʊnjʊˌkliːɪk, -ˌkleɪɪk/; DNA) is a molecule that carries the genetic instructions used in the growth, development, functioning and reproduction of all known living organisms and many viruses. DNA and RNA are nucleic acids; alongside proteins, lipids and complex carbohydrates (polysaccharides), they are one of the four major types of macromolecules that are essential for all known forms of life. Most DNA molecules consist of two biopolymer strands coiled around each other to form a double helix.
The two DNA strands are termed polynucleotides since they are composed of simpler monomer units called nucleotides. Each nucleotide is composed of one of four nitrogen-containing nucleobases—either cytosine (C), guanine (G), adenine (A), or thymine (T)—and a sugar called deoxyribose and a phosphate group. The nucleotides are joined to one another in a chain by covalent bonds between the sugar of one nucleotide and the phosphate of the next, resulting in an alternating sugar-phosphate backbone. The nitrogenous bases of the two separate polynucleotide strands are bound together (according to base pairing rules (A with T, and C with G) with hydrogen bonds to make double-stranded DNA. The total amount of related DNA base pairs on Earth is estimated at 5.0 x 1037, and weighs 50 billion tonnes. In comparison, the total mass of the biosphere has been estimated to be as much as 4 trillion tons of carbon (TtC).
WHITEOUT CLOUDMAKER DNA AND SX PANELS!!!!!!
Thread by: MoneymanVape, 11/2/18, 2 replies, in forum: Help My Vape Broke!
Hi there, i was wondering if anybody knows where i can get a dna 250

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Retrieved Text: There are four main types of biomolecules: carbohydrates, proteins, lipids, and nucleic acids. These biomolecules make up the cells that make up organisms and are responsible for the mechanisms within the body. Carbohydrates are composed of carbons, hydrogens, and oxygens. Monosaccharides bond to form oligosaccharides that can be bound to cell surface proteins to aid in cell signaling. Proteins are made up of amino acids, which are composed of a central carbon bound to an amino group, a carboxyl group, and a variable "R" group. The R group can be nonpolar, polar without charge, negatively charged, or positively charged, and the polarity of the R group will influence how different amino acids interact intramolecularly or intermolecularly with other molecules. On the other hand, lipids are made up of mainly hydrocarbons and are therefore insoluble in water. The saturation of different lipids vary, affecting the solidity of the lipid at room temperature. Fully saturated lipids have carbons saturated with hydrogens, while unsaturated lipids have double bonds between carbons, resulting in less surrounding hydrogens. Lastly, nucleic acids are composed of nucleotides that consist of a sugar ring, a phosphate group, and a nitrogenous base. The most recognized nucleic acid is DNA, and in DNA, nucleotide phosphate groups and sugars form phosphodiester bonds that make up the sugar-phosphate backbone. The nitrogenous bases form hydrogen bonds across the two strands of DNA to form the DNA ladder.
Specify that carbon, hydrogen, and oxygen are molecules, saying "carbons, hydrogens, and oxygens" sounds a bit funky.
After completing the summary of what the biomolecules

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Retrieved Text: A chromosome is made up of long, coiled up molecule called DNA.
The phosphate and sugar group join, and the nitrogen base combines with the sugar group forming a nucleotide. The base pairs from two nucleotides are attracted together via hydrogen bonding. Although hydrogen bonds are weak but because they are thousands of nucleotides, together they form the double helix shaped DNA molecule in which the phosphate a sugar groups form the backbone. In this way a DNA molecule is similar in structure to a ladder in which the sugar and phosphate groups make the uprights and the nitrogen base groups the rungs.
There are four types of nitrogen bases or base groups.
The animation below shows how the nitrogen base groups pair up to form the DNA molecule.
These are the four base groups in a DNA molecule.
For simplicity, the chemical structures of the base groups are shown as simple shapes and their full names are replaced by the starting letter.
Nucleotides are the building blocks of a DNA molecule. Each nucleotide is made up of a phosphate group linked to a deoxyribose sugar which, in turn, is linked to one of the four nitrogen bases.
For simplicity, the chemical structures are shown as simple shapes.
The bases in the nucleotides always pair up in the same way.
Each pair is held together by hydrogen bonds.
The nucleotides in the DNA molecule are linked in series from one phosphate, to the next sugar, to the next phosphate and so on. The DNA molecule can be considered as a ladder with the phosphate and the

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Retrieved Text: A cell’s hereditary information is encoded in chromosomes in the cell’s nucleus. Each chromosome is composed of proteins and deoxyribonucleic acid (DNA). The chromosomes contain smaller hereditary units called genes, which are relatively short segments of DNA. The hereditary information is expressed or used through the synthesis of ribonucleic acid (RNA). Both nucleic acids—DNA and RNA—are polymers composed of monomers known as nucleotides, which in turn consist of phosphoric acid (H3PO4), a nitrogenous base, and a pentose sugar.
The two types of nitrogenous bases most important in nucleic acids are purines—adenine (A) and guanine (G)—and pyrimidines—cytosine (C), thymine (T), and uracil (U). DNA contains the nitrogenous bases adenine, cytosine, guanine, and thymine, while the bases in RNA are adenine, cytosine, guanine, and uracil. The sugar in the nucleotides of RNA is ribose; the one in DNA is 2-deoxyribose. The sequence of nucleotides in a nucleic acid defines the primary structure of the molecule.
RNA is a single-chain nucleic acid, whereas DNA possesses two nucleic-acid chains intertwined in a secondary structure called a double helix. The sugar-phosphate backbone forms the outside the double helix, with the purine and pyrimidine bases tucked inside. Hydrogen bonding between complementary bases holds the two strands of the double helix together; A always pairs with T and C always pairs with G.
Cell growth requires replication, or reproduction of the cell’s DNA. The double helix unwinds, and hydrogen bonding between complementary bases breaks so that there are two single strands of DNA, and each strand is a template for the synthesis of a new strand.

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Retrieved Text: "ACGT" redirects here. For the Japanese animation production company, see A.C.G.T.
Base pairing: Two base pairs are produced by four nucleotide monomers, nucleobases are in blue. Guanine (G) is paired with cytosine (C) via three hydrogen bonds, in red. Adenine (A) is paired with uracil (U) via two hydrogen bonds, in red.
Purine nucleobases are fused-ring molecules.
Pyrimidine nucleobases are simple ring molecules.
Nucleobases, also known as nitrogenous bases or often simply bases, are nitrogen-containing biological compounds that form nucleosides, which in turn are components of nucleotides, with all of these monomers constituting the basic building blocks of nucleic acids. The ability of nucleobases to form base pairs and to stack one upon another leads directly to long-chain helical structures such as ribonucleic acid (RNA) and deoxyribonucleic acid (DNA).
Five nucleobases—adenine (A), cytosine (C), guanine (G), thymine (T), and uracil (U)—are called primary or canonical. They function as the fundamental units of the genetic code, with the bases A, G, C, and T being found in DNA while A, G, C, and U are found in RNA. Thymine and uracil are identical excepting that T includes a methyl group that U lacks.
Adenine and guanine have a fused-ring skeletal structure derived of purine, hence they are called purine bases. Similarly, the simple-ring structure of cytosine, uracil, and thymine is derived of pyrimidine, so those three bases are called the pyrimidine bases. Each of the base pairs in a typical double-helix DNA comprises a purine and a pyrimidine: either an A paired with a T or a C paired with a G. These

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Retrieved Text: DNA is a nucleic acid (NA) with deoxyribose (D) sugar molecules. Its complex structure can be broken down into simple chemical blocks of sugar, base, and phosphate group, which together constitute the nucleotide. Yes, DNA is unaware of what we are doing with our knowledge of its structure after 60 years of its discovery! We are decoding the genetic recipe of life forms on the planet through genome sequencing, creating genetic profiles, manipulating the genetic sequences, recombining, mining and engineering them, modelling and designing artificial nucleic acid structures and so on. All this is possible because we know the chemistry of DNA.
In this article, I’ll focus on elementary chemistry concepts which form the basis for the understanding of the DNA structure. A brief on DNA’s structural discovery and details follow.
In late 1920s, the chemical components of DNA were identified to be phosphate, sugar, and base by Phoebus Levene, an American biochemist. Levene showed that the three components were linked in the same order as above to form a chemical unit, which he termed – ‘nucleotide’. There was speculation regarding the actual structure of the DNA molecule but it was only in 1953 that the structure was discovered, to what Henderson (2008) says is a story of luck, brilliance, and deviousness.
There were two major insights that led to the discovery of the structure of the deoxyribonucleic acid (DNA) molecule. The first came from the work of an Austrian biochemist, Erwin Chargaff. In 1952, while based in Columbia University in the United States, through meticulously designed experiments and

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Retrieved Text: What Causes the Double Helix to Twist in a DNA Picture?
Deoxyribonucleic acid is present in the nucleus of every cell in our body in compactly folded up forms called chromosomes. The four building blocks that make up the DNA are repeated to form a long chain. They encode a vast amount of information, ranging from eye color to the predisposition to a disease.
Nucleotides are the subunits of DNA. The four nucleotides are adenine, cytosine, guanine and thymine. Each of the four bases has three components, a phosphate group, a deoxyribose sugar and a nitrogen-containing base. The nitrogenous base attached to the bases may be a double-ringed purine or a single-ringed pyrimidine. Adenine and guanine are purine bases, while cytosine and thymine are pyrimidine bases. These four nucleotides, referred to as the A, C, G and T are the building blocks of DNA.
The four nucleotides join with each other and form what is famously known as the DNA ladder. Hydrogen bonds form only between a purine and a pyrimidine nucleotide base, so the adenine always binds to thymine and cytosine to guanine to form a long chain. Further linking on the DNA ladder occurs by the bonding of the sugar of one nucleotide to the sugar of the adjoining nucleotide by a phosphate group. The sugar phosphate bonding forms the sides of the DNA ladder and is responsible for the twist in DNA.
The Human Genome Project determined the sequence of the three billion bases present in human DNA. The arrangement of these bases encode for the 20,000

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Retrieved Text: Nucleotides are the basic structural units of nucleic acids, which control the production of proteins in living organisms. The nucleotides are made up of a phosphate group, a pentose sugar, and a nitrogen base.
This shows the basic structure of a nucleotide. This example has the sugar ribose, and is characteristic of RNA. The nucleotide could contain the sugar deoxyribose, characteristic of DNA. For DNA, the bases may be adenine, guanine, cytosine or thymine. For RNA the bases are adenine, guanine, cytosine and uracil.

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Retrieved Text: Nucleic acids are the fourth class of biological molecule. They store information. A nucleic acid is a nitrogen containing biological polymer that is involved in storage and transmission of genetic information.
The monomer that makes up a nucleic acid is called a nucleotide. Each nucleotide has three parts: 1. Inorganic phosphate group, 2. A five-carbon monosaccharide sugar, and 3. A nitrogen base.
In a nucleic acid, the sugar of one bonds to the phosphate of another. This makes them string together in a chain. Each sugar is also bonded to a nitrogen base.
DNA and RNA are nucleic acids. DNA carries genetic information. RNA allows cells to use the information found in DNA, and determines the sequence of amino acids that form proteins. DNA consists of two long chains of nucleotides wound together to form a spiral structure. The sugar is deoxyribose, and there are four nitrogen bases: adenine, thymine, guanine and cytosine. RNA is single stranded, and the sugar is ribose, with nitrogen bases A C G and U, which is uracil.

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Retrieved Text: Widespread throughout animal and plant tissue, purine components of DNA, RNA, and coenzymes. Vitamin Adenine (sometimes known as vitamin B4) combines with the sugar ribose to form adenosine, which in turn can be bonded with from one to three phosphoric acid units, yielding AMP, ADP and ATP . These adenine derivatives perform important functions in cellular metabolism. Adenine is one of four nitrogenous bases utilized in the synthesis of nucleic acids. A modified form of adenosine monophosphate (cyclic AMP) is an imporant secondary messenger in the propagation of many hormonal stimuli. Adenine is an integral part of the structure of many coenzymes. Adenosine (adenine with a ribose group) causes transient heart block in the AV node of the heart. In individuals suspected of suffering from a supraventricular tachycardia (SVT), adenosine is used to help identify the rhythm. Certain SVTs can be successfully terminated with adenosine.; Adenine forms adenosine, a nucleoside, when attached to ribose, and deoxyadenosine when attached to deoxyribose. It forms adenosine triphosphate (ATP), a nucleotide, when three phosphate groups are added to adenosine. Adenosine triphosphate is used in cellular metabolism as one of the basic methods of transferring chemical energy between chemical reactions.; Adenine is a nucleobase (a purine derivative) with a variety of roles in biochemistry including cellular respiration, in the form of both the energy-rich adenosine triphosphate (ATP) and the cofactors nicotinamide adenine dinucleotide (NAD) and flavin adenine dinucleotide (FAD), and protein synthesis, as a chemical component of DNA and RNA. The shape of adenine is complementary to either thymine in DNA

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Retrieved Text: Proteins are made up of amino acids which are joined together by peptide bonds.
Amino acids are amphoteric in nature as it contains an amino group (-NH2) and a carboxyl group (-COOH).
Structure of protein is determined by the number of amino acids and their kind and order in which they arranged in the polypeptide chain.
Proteins are globular or fibrous in shape.
Globular proteins play a functional role and fibrous protein plays a structural role.
Protein is the main constituent of enzymes which are responsible for biochemical reactions in cells.
It helps in respiration process by transport of oxygen.
Nucleic acids are polynucleotide made up of by joining two or more nucleotide unit together.
Each nucleotide is made up of three sub units – sugar, nitrogenous base and phosphoric acid.
Sugar is pentose type where DNA contains Deoxyribose sugar and RNA contains rebose sugar.
Phosphoric acid is associated with phosphate.
Nucleoside is then attached with phosphoric acid by ester bond and forms nucleotide.
Nucleotide joins together by phspho-di-ester bond and forms a chain of nucleotide called as polynucleotide.
RNA contains one polynucleotide chain whereas DNA contains two polynucleotide chains.
It acts as a currency of energy in cell in form of ATP.
They are responsible for inheritance inc all organism.
Example-1: Which of the following is not present in DNA?
Answer: DNA does not contain Uracil.
Example-3: Which of the following is the building block of proteins?

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Retrieved Text: Deoxyribonucleic acid (DNA) transcription is the process by which DNA inside cells in the human body are converted into ribonucleic acid (RNA) in order to create genes and produce proteins. DNA transcription occurs when an enzyme known as RNA polymerase unzips the double-stranded DNA molecule by breaking down the bonds between connecting nucleotides, the molecules that form the basis of DNA and RNA. Once the DNA is unzipped, RNA nucleotides join up with their complementary DNA nitrogenous bases to form a long strand of RNA. The RNA polymerase then helps to form a sugar-phosphate backbone that links all the RNA bases together. Upon completion of the RNA strand, it is released from the DNA molecule, and the process of transcription is accomplished.
RNA is very similar to DNA, except that it consists of a single strand and not a double strand. It also has a slightly different molecular structure in that it contains uracil, a nitrogen-based compound that is a part of live tissue. On the other hand, DNA contains thymine, a compound that consists of nitrogen and carbon. The process by which the code for a specific protein is transferred from DNA to RNA is known as DNA transcription.
Once DNA transcription has taken place, a new protein can be created through the process of DNA translation. In translation, the newly formed RNA strand pairs up with complementary bases to create a code for producing a protein. This code serves as a type of instruction manual and can then be used by ribosomes inside the cell to

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Retrieved Text: Nucleosides are the precursor molecules for the monomers (nucleotides) that make up the nucleic acids DNA and RNA. They consist of glycoslyamines made by attaching an organic nucleobase (like adenine, cytosine, guanine, uracil or thymine) to a five-carbon (pentose) ribose sugar ring for RNA or to a deoxyribose ring for DNA. They are converted into nucleotides by the addition of a phosphate group in the process of phosphorylation. They can also be formed by partial hydrolysis of a nucleic acid. Nucleotides are single monomer units for DNA and RNA molecules consisting of a base nucleoside, adenine, thymine, guanine or cytosine, a ribose or deoxyribose sugar and a phosphate group. Adenine, guanine and cytosine occur in both RNA and DNA. Thymine occurs only in DNA and uracil only in RNA. They are abbreviated A, G, C and T in DNA and A, G, C and U in RNA. Thousands of nucleotides linked together make up a DNA or RNA molecule. The base sequences in DNA and RNA contain the genetic information of a cell. The sequence of the bases within the nucleic acid determines which proteins will be made. The sequence of a DNA or RNA molecule is usually described as the sequence of its bases, e.g. AAAAGTTCGTCTAGGTC. Three nucleotides in a gene form a codon that encodes a single amino acid in a protein sequence. Ribose-containing nucleosides include ribonucleoside monophosphate (NMP), ribonucleoside diphosphate (NDP), and ribonucleoside triphosphate (NTP). When the nucleoside contains the sugar deoxyribose, the nucleotides are called deoxyribonucleoside mono-, di-, or tri-phosphates (dNMP, dNDP,

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Retrieved Text: On this page, you can see a double-stranded DNA molecule. While it spins, notice the larger major groove and the smaller minor groove.
Reset and spin this DNA molecule.
Notice the two strands of this DNA molecule.
The two strands of DNA are in opposite orientations so that one chain's 5' phosphate group (yellow) is near the other chain's 3' hydroxyl group (purple).
Look at the backbones for each strand. The backbones are composed of ribose + phosphate + ribose + phosphate.... There are only pale blue nubs where the bases have been deleted for clarity.
Look at the AT base pairs are shown in CPK colors. The backbones are colored by strands and all GC base pairs have been deleted. Hydrogen bonds are shown as dotted lines (even when GC pairs are deleted). How many H-bonds are there between AT base pairs?
Zoom out by using the shift key and mousing up.
Look at the GC base pairs are shown in CPK colors. The backbones are colored by strands and all AT base pairs have been deleted. Hydrogen bonds are shown as dotted lines (even when AT pairs are deleted). How many H-bonds are there between GC base pairs?

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Retrieved Text: Phosphate, chemical formula PO43-, is a chemical compound made up of one phosphorus and four oxygen atoms. When it is attached to a molecule containing carbon, it is called a phosphate group. It is found in the genetic material DNA and RNA, and is also in molecules such as adenosine triphosphate (ATP) that provide energy to cells. Phosphates can form phospholipids, which make up the cell membrane. Phosphate is also an important resource in ecosystems, especially in freshwater environments.
This figure depicts a phosphate group.
DNA and RNA, the genetic material of all living things, are nucleic acids. They are made up of nucleotides, which in turn are made up of a nitrogenous base, a 5-carbon sugar, and a phosphate group. The 5-carbon sugar and the phosphate group of each nucleotide attaches to form the backbone of DNA and RNA. When nucleotides are not attached to other nucleotides to form part of DNA or RNA, two more phosphate groups are attached.
Phosphate groups are important in activating proteins so that the proteins can perform particular functions in cells. Proteins are activated through phosphorylation, which is the addition of a phosphate group. Protein phosphorylation occurs in all forms of life. Dephosphorylation, the removal of a phosphate group, deactivates proteins.
Adenosine triphosphate, or ATP, is the main source of energy in cells. It is made up of adenosine and three phosphate groups, and the energy derived from ATP is carried in the phosphates’ chemical bonds. When these bonds are broken, energy is released. ATP is formed when the molecule ADP (adenosine diphosphate)

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Retrieved Text: ﻿ What Is The Structure Of A DNA Molecule?
A molecule of DNA is double-stranded. The molecule has the shape of a double helix.
The DNA molecule consists of two complementary strands oriented in an anti-parallel fashion. Each strand is composed of nucleotides. A nucleotide consists of a base (a purine or pyrimidine), a sugar (between the other two components) named deoxyribose, and a phosphate group. Nucleotides are linked to each other via phosphodiester bonds, forming a sugar-phosphate backbone to each strand.
The base of each nucleotide projects into the interior cavity of the helix. Each base is opposite another base: adenine (a purine) is always paired with thymine (a pyrimidine), and guanine (purine) with cytosine (pyrimidine); this phenomenon is called complementary base pairing.
Each nucleotide forms hydrogen bonds with its complementary base on the other strand. Two hydrogen bonds form between adenine and thymine; three hydrogen bonds form between guanine and cytosine.
What is the difference between the law of multiple proportions and the law of definite proportions? What is a medicine dropper?

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Retrieved Text: Describe why the cell makes polymers and the important polymers of the cell.
Explain how sugars monomers are put together to make polymers.
Explain the chemical and structural differences between DNA and RNA.
Living systems are made of organic molecules, and the cell has settled on just a few types of molecules to make up the majority of its structures: sugars, nucleic acids, amino acids and lipids. It is somewhat shocking that the list is so short, but it demonstrates the elegance of the whole system.
Monomers are all well and good, but cells are much larger than the molecular scale. How do they do it? These single molecular units are linked together by the cellular machinery into long chains of monomers, called polymers. Polymers make up the bulk of what a cell is, dictating its structure and function. Proteins are polymers of amino acids and they drive the chemical reactions of the cell or serve as parts of important structures. Starch is a polymer of glucose and polysaccharides are polymers of sugars that serve in the cell wall, the cell membrane and as storage products. DNA is a polymer of nucleic acids and is the library that stores the recipes for making an organism.
For polymers made up of more than one monomer, there are several important implications. How each polymer behaves is dictated by the order in which the monomers appear in the sequence of the polymer. Each specific combination of monomers will create a unique polymer that has a specific structure and function. Changing any one of the

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Retrieved Text: There is only one type of DNA.
The sugar in DNA is deoxyribose.
There a 2 strands held together in DNA.
DNA has 4 nitrogenous bases which are Thymine, Adenine, Cytosine, Guanine.
DNA replicates another copy of itself through mitosis and meiosis.
There are 3 different types of RNA. Messenger RNA (mRNA), Ribosomal RNA (rRNA), Transfer RNA (tRNA).
The sugar in RNA is ribose.
RNA is single stranded and connects with an anti-codon.
RNA has 4 nitrogenous bases which are Uracil, Adenine, Cytosine, and Guanine.
mRNA is transcribed from DNA.

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Retrieved Text: Deoxyribonucleic acid is better known by its shorter name DNA. The determination of DNA’s structure in 1953 by Francis Crick and Jim Watson is hailed by many to be the most important discovery ever in human history.
DNA is life’s hereditary material, i.e. it holds and passes on the genetic information from parents to offspring. The information carried by DNA directs the construction of each organism, its maintenance, proper functioning and reproduction.
The information is carried in coded form as sequence of specific chemicals called nitrogenous bases. Just as a computer code is a unique sequence of 0s and 1s, so is life’s genetic code a unique sequence of bases.
There are about 2.5 metres of DNA in the nuclear DNA of each human cell. Therefore, we each have about 250 billion kilometres of DNA in our body. Every second we make enough DNA to encircle the equator 3 times. We make about 50 million new cells every second.
DNA structure is described as a double helix. It is like a spiral ladder and is composed of two complementary polynucleotide strands held together by hydrogen bonds.
In DNA the sugar is deoxyribose and because there are four different bases – adenine (A), guanine (G), thymine (T) and cytosine (C) - there are four different nucleotides. The nucleotides are PSA, PSG, PST, PSC.

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Retrieved Text: Deoxyribonucleic acid (DNA) is the basic hereditary material found in the nucleus of most cells. This genetic information is passed on from one generation to the next and is required for protein synthesis. This important life information is packaged in the nucleus in a highly structured and organised manner. DNA is tightly wrapped around proteins called histones and this complex structure is the nucleosome. Nucleosomes are the structural and functional units of a chromatin. These are then folded and looped over other proteins and this chromatin is further compressed into the chromatid of a chromosome.
DNA is a linear polymer that is made up of nucleotide units. The nucleotide unit consists of a base, a deoxyribose sugar, and a phosphate. There are four types of bases: adenine (A), thymine (T), guanine (G), and cytosine (C). Each base is connected to a sugar via a ß glycosyl linkage. The nucleotide units are connected via the O3' and O5' atoms forming phosphodiester linkages.In normal DNA, the bases form pairs: A to T and G to C. This is called complementarity. A duplex of DNA is formed by two complementary chains that are arranged in an anti-parallel manner.
NDB ID: BD0002 Throughtout the site, in all DNA nucleotide block models, adenine is red, thymine is blue, cytosine is yellow, guanine is green.
DNA can have several conformations. The most common one is called B-DNA. B-DNA is a right-handed double helix with a wide and narrow groove. The bases are perpendicular to the helix axis. DNA can also be found in the A

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Retrieved Text: #42302952 - DNA structure: Nucleotide, Phosphate, Sugar, and bases (thymine,..
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#29139363 - Structural chemical formula and model of cytidine, 2D and 3D..

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Retrieved Text: CHITIN: used in fungi cell walls, arthropod, exoskeletons, and dissolving stitches.
1) TRIGLYCERIDES: consists of 3 fatty acids attached to a glycerol molecule. fatty acids vary in structure by the number of carbons and by the placement of single and double covalent bonds between the carbons.
2) PHOSPHOLIPID: looks just like a lipid except that one of the fatty acid chains is replaced by a phosphate group. the two fatty acid "tails"of the phospholipid are nonpolar and hydrophobic and the phosphate "head" is polar and hydrophilic. a phospholipid is termed an Amphipathic molecule because it has both polar and nonpolar regions.
Monounsaturated: fatty acid has one double covalent bond and each of the two carbon in this bond has only one hydrogen atom bonded to it.
Polyunsaturated: fatty acid is like a monounsaturated fatty acid except that there are two or more double covalent bond.
Saturated: fatty acid has a single bond between each pair of carbon atoms and each carbon has two hydrogen bonds.
Amino acid are joined by "peptide bonds"
2) SECONDARY STRUCTURE: of a protein three-dimensional shape that results from hydrogen bonding between Amino & Carboxyl group of adjacent amino acids. spiral (alpha helix) or folded plane (beta pleated sheets) both form Fibrous proteins.
3) TERTIARY STRUCTURE: of a protein additional three-dimensional shaping and often dominates the structure of Globular proteins. contributing factors: Hydrogen & ionic bonding between R groups of amino acids. Hydrophobic effect that occurs when hydrophobic R groups move toward the center of the protein (away from water). Formation of Disulfide bonds helps maintain turns of the amino

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Retrieved Text: Biomolecules and biomolecular assemblies interact in specific, highly-regulated ways to transfer sequence information between biopolymers in living organisms. By storing and transferring biological information, DNA and RNA enable living organisms to reproduce their complex components from one generation to the next. The nucleotide monomers of these biopolymers, being joined by phosphodiester linkages, form a polynucleotide molecule with a “backbone” composed of repeating sugar-phosphate units and “appendages” of nitrogenous bases. The unique sequence of bases in each gene provides specific information to the cell.
DNA molecules are composed of two polynucleotides that spiral around an imaginary axis, forming a double helix. The two polynucleotides are held together by hydrogen bonds between the paired bases and van der Waals interactions between the stacked bases. The pairing between the bases of two polynucleotides is very specific, and its complementarity allows for a precise replication of the DNA molecule.
The DNA inherited by an organism leads to specific traits by dictating the synthesis of the biomolecules (RNA molecules and proteins) involved in protein synthesis. While every cell in a multicellular organism inherits the same DNA, its expression is precisely regulated such that different genes are expressed by cells at different stages of development, by cells in different tissues, and by cells exposed to different stimuli.
The topics included in this category concern not only the molecular mechanisms of the transmission of genetic information from the gene to the protein (transcription and translation), but also the biosynthesis of the important molecules and molecular assemblies that are involved in these mechanisms. The control of gene

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Retrieved Text: A Bacterial cell under an electron microscope reveals many components, some of which are external to the cell wall and some are internal to the cell wall. Some of the structures are confined only to certain species and some other structures act as the characteristic features of certain species. Structures external to the cell wall include flagella, capsules and sheaths. Structures internal to the cell include cytoplasmic membrane and all other cytoplasmic inclusions.
Cell wall is a very rigid structure which provides support and gives shape to the cell. It is about 100-140 nm in thickness. Most of the bacteria live in hypotonic environments and tend to take up water due to the variation in the osmotic pressures between the bacterial cells and the existing environment. Hence, the main function of the cell wall is to prevent the cell from expanding and eventually bursting in the hypotonic environments. Bacterial cell has the ability to retain their original shape when subjected to very high pressures, due to the rigidity of the cell wall.
Cell wall is composed of two polymers, one consisting of saccharide subunits and the other consisting of amino acid subunits. Thus a bacterial cell wall is glycopeptide which is also known as peptidoglycan. The saccharide component of the cell wall has alternating repeating units of two amino sugars related to glucose. One of these two is NAM (N-Acetyl Muramic acid) and the other is NAG (N-Acetyl glucosamine). Both NAG and NAM form the back bone of the cell wall structure.
The alternating units of NAG and NAM

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Retrieved Text: A critical clue to understanding the structure of nucleic acids came from the work of Erwin Chargaff (1905–2002). When analyzing DNA from various sources, he found that the relative amounts of G, C, T and A nucleotides varied between organisms but were the same (or very similar) for organisms of the same type or species. On the other hand, the ratios of A to T and of G to C were always equal to 1, no matter where the DNA came from. Knowing these rules, James Watson (b 1928) and Francis Crick (1916–2004) built a model of DNA that fit what was known about the structure of nucleotides and structural data from Rosalind Franklin (1920–1958)206. Franklin got these data by pulling DNA molecules into oriented strands, fibers of many molecules aligned parallel to one another. By passing a beam of X-rays through these fibers she was able to obtain a diffraction pattern. This pattern is based on the structure of DNA molecules and defines key parameters that constrain any model of the molecule’s structure. But making a model of the molecule that would produce the observed X-ray data allowed Watson and Crick to make conclusions about the structure of a DNA molecule.
To understand this process, let us consider the chemical nature of a nucleotide and a nucleotide polymer like DNA. First the nucleotide bases in DNA (A, G, C and T) have a number of similar properties. Each nucleotide has three hydrophilic regions: the negatively charged phosphate group, a sugar which has a number of O–H

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Retrieved Text: In 28 September 1969, fragments of a meteorite landed 2 kilometres south of the small village of Murchison, Victoria, Australia. Local residents collected about 100 kg of material, and the largest fragment was about 7 kg.
The Murchison fragments came from a class of meteorite called carbonaceous chondrites, because they contain small nodules called chondrules. Since this class is rich in carbon and water, right from the beginning the Murchison meteorite has been analysed for organic molecules. Chemical evolutionists, who have faith that life evolved from non-living chemicals, were hoping to find evidence to support their faith. They had hoped that this meteorite would provide evidence that such processes were widespread in the universe, even if some of them were pessimistic that life could arise on earth.
One of the first discoveries was amino acids, the components of proteins. Later, there were dubious claims that some of the amino acids had a slight excess of the ‘handedness’ (chirality) required for life, as we have reported. Still later, there were claims that sugars and sugar-related compounds were discovered, which excited many because the backbones of DNA and RNA contain the sugars deoxyribose and ribose respectively. But see our report on why this offers no support for chemical evolution.
Read the rest of "Nucleic acid bases in Murchison meteorite?" here.

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Retrieved Text: Containing over three billion cells - each with a specific job to do - your body is a wonder to behold. Learn how it works, by creating your very own liquorice double helix (DNA), laced with gummy bear bases!
Some cells help us to see, others give us our sense of taste or touch. Other cells allow our bodies to jump, or run, or blow a bubble, or throw a ball. But how do the cells know which job to do? The answer is found in DNA: the body’s very own blueprint or instruction manual. Take your child on an adventure into the unknown with this fun, tasty STEM activity.
Begin by talking to your child about DNA.This video is a great place to start.
Gather your sweets. To make the sugar and phosphate sides, we recommend using strands of black and red liquorice. For the nitrogenous bases, we recommend using gummy bears. If you choose different sweets, ensure they’re soft enough to puncture with a toothpick.
Gather some string and at least a dozen toothpicks.
Cut the string to around a foot long.
Cut the liquorice into individual pieces, measuring around one inch each.
The four letters of the DNA alphabet are similar to pieces of a jigsaw puzzle. Cytosine and guanine (C and G) fit together, while thymine and adenine (T and A) fit together. Choose four different colored gummy bears to represent these nitrogenous bases, and help your child to pair them up accordingly. It doesn’t matter if a pair goes C–G or G–C, as long as those are always

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Retrieved Text: The term sugar is the generic term for any disaccharides and monosaccharides. Sugars are an essential structural component of living cells and a source of energy in many organisms. Sugars are classified based on the number of monomeric units present. The term simple sugars denote to the monosaccharides. The term table sugar or granulated sugar actually refers to sucrose, which is a disaccharide made of two monosaccharides: glucose and fructose. Sucrose is the form of sugar that many people are familiar with. It is used in food preparation, such as in cakes, pastries, and desserts. It is also used as an ingredient in several beverages, such as sodas, coffee, and juices.
Carbohydrates, especially polysaccharides, are one of the four major groups of biomolecules. The others are proteins, amino acids, and nucleic acids. A carbohydrate refers to any of the group of organic compounds consisting of carbon, hydrogen, and oxygen, usually in the ratio of 1:2:1, hence the general formula: Cn (H2O) n. Carbohydrates are the most abundant among the major classes of biomolecules. They are one of the major nutrients, providing energy that shall fuel various metabolic processes.
As a nutrient, carbohydrates may be classified based on their structural complexity: simple and complex. Simple carbohydrates, sometimes referred to as simply sugar, are those that are readily digested and serve as a rapid source of energy. Complex carbohydrates (such as cellulose, starch, and glycogen) are those that need more time to be digested and metabolized. They often are high in fiber and unlike simple carbohydrates they are less likely

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Input Text: Answer the following question given this paragraph: 

Figure 33.18 Smooth muscle cells do not have striations, while skeletal muscle cells do. Cardiac muscle cells have striations, but, unlike the multinucleate skeletal cells, they have only one nucleus. Cardiac muscle tissue also has intercalated discs, specialized regions running along the plasma membrane that join adjacent cardiac muscle cells and assist in passing an electrical impulse from cell to cell.


Q: Skeletal muscle cells and cardiac muscle cells share what property, which is not shared by smooth muscle cells?

 Choices:

- surfaces

- filaments

- overlap

- striations

A:

Target Text: striations

#### Retrieved Documents ####

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Retrieved Text: Animal tissues. Muscle. Atlas of Plant and Animal Histology.
Muscle tissue drives the body and organs movement. Muscle cells are known as myocytes or muscle fibers. They have the ability to decrease their length, which in turn produces muscle contraction. The contractile capacity depends on the association of actin filaments and myosin II motor protein filaments in the cytoplasm.
Muscle cells are divided into three types: skeletal, smooth and cardiac. Skeletal muscle cells are very long cells that show dark striations, which are perpendicular to the cell longitudinal axis when observed at light microscopy, hence they are also referred as striated skeletal muscle cells. Although cardiac muscle cells, or cardiomyocytes, also show striations, they are regarded as semi-striated. These dark transverse lines do not appear in smooth muscle cells.
Striated skeletal muscle cells of the upper part of the mouse esophagus.
Striated skeletal muscle is also referred as voluntary because it is responsible for conscious or voluntary movements. It is innervated by nerve fibers coming from the central nervous system. Striated skeletal muscle is usually attached to bones through tendons, but not always, like the muscles of the eye, upper esophagus and tongue.
Skeletal muscles is made up of striated muscle cells, also known as muscle fibers or myocytes, as well as connective tissue, nerves and blood vessels. Striated skeletal muscle cells join together to form muscle fascicles, and muscle fascicles form the skeletal muscle, main responsible for the movements of the animals. Muscle cells are wrapped by a special extracellular matrix known as basal lamina, plus reticular and collagen fibers

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Retrieved Text: Search for What Does The Cardiac Muscle Cell Do. Direct CBSi results here!
Search Cardiac Muscle Cell on Nation.com and Get Instant Results.
Cardiac muscle cells or cardiomyocytes (also known as myocardiocytes or cardiac myocytes) are the muscle cells that make up the cardiac muscle (heart muscle). Each myocardial cell contains myofibrils, which are specialized organelles consisting of long chains of sarcomeres, the fundamental contractile units of muscle cells.. Cardiomyocytes show striations similar to those on skeletal muscle cells.
Cardiac muscle fibers cells also are extensively branched and are connected to one another at their ends by intercalated discs. An intercalated disc allows the cardiac muscle cells to contract in a wave-like pattern so that the heart can work as a pump.
Cardiac Muscle Cells This is a high power view of cardiac muscle cells. Like smooth muscle, each cardiac muscle cell has a single (sometimes two) centrally located nucleus. Like skeletal muscle, cardiac muscle cells are striated due to a similar arrangement of contractile proteins.
Cardiac Muscle Definition. Cardiac muscle, also known as heart muscle, is the layer of muscle tissue which lies between the endocardium and epicardium.These inner and outer layers of the heart, respectively, surround the cardiac muscle tissue and separate it from the blood and other organs. Cardiac muscle is made from sheets of cardiac muscle cells.
A group led by Teruo Okano, a professor of regenerative medicine at Tokyo Women's Medical University, and Yoshiki Sawa, a cardiovascular surgeon at Osaka University, successfully cultivated newborn rats' cells to form a sheet of cardiac muscle and used the sheet

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Retrieved Text: What is a Smooth Muscle?
The iris is one of the body's smooth muscles, which lack striations and contract without conscious control.
Smooth muscle is one of three types of muscles in the body.
Smooth muscle may be found in the trachea.
Smooth muscle can be found in the bladder.
Smooth muscles exist in the female reproductive tract.
Smooth muscle is one of the three different muscle types found in the body. It is involuntary, or contracts without conscious control, and unlike other muscle types, it lacks striations. Since it allows elasticity while maintaining an ability to contract, this type of muscle is suited for hollow organs in the body that need to expand and contract in order to hold and pass different substances, such as urine or blood. Its locations include blood vessels, lymphatic vessels, the gastrointestinal (GI) tract, the uterus, male and female reproductive tracts, the bladder, the respiratory tract, the iris, the arrector pili, and the ciliary muscle.
The other two types of muscle, skeletal and cardiac, are quite different from smooth muscle in form as well as function. Most strikingly different is this muscles' lack of striations, or stripes that run across the muscle cells, or fibers. In skeletal and cardiac muscles, the contractile components of the muscle fibers are organized into sarcomeres, and the end and middle of each sarcomere appear as stripes. Smooth muscle is not organized into sarcomeres. Like cardiac muscle, but unlike skeletal muscle, the cells typically have just one nucleus, typically located in the middle of the fiber. Under a microscope, one can tell

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Retrieved Text: Highly specialized in form and function, each muscle cell optimally performs its required function, though there is variation amongst muscle cells within each category. Three different types of muscle cells make up the human body: skeletal, smooth, and cardiac. Humans classify them as either voluntary or involuntary, depending on whether humans consciously control their movements. Further classified by appearance, muscles can appear smooth or striated, having a striped appearance.
Bodies contain three types of muscle cell: skeletal, smooth, and cardiac. Each serves a different, but important, function in human life.
Skeletal muscle cells form elongated fibers in the body. They have multiple nuclei within each cell. This contrasts with the majority of other cells in human bodies. They also contain many mitochondria, cellular organelles that produce adenosine triphosphate (ATP), the body’s fuel. The short, non-striated — and, hence — smooth muscle cells contain only one nucleus. Cardiac muscle cells appear striated, though they also appear less organized into stripes than skeletal muscle cells. These cells may branch out, forming physical connections with many surrounding cells.
According to BMH Linguistics, skeletal muscle cells make up the bulk of muscles in human bodies. These muscle fibers attach to bones allowing movement in joints. As well, humans use skeletal muscles to maintain posture. Smooth muscle cells are found lining internal organs and blood vessels in humans, and they are responsible for the contraction of organs, such as the bladder. Smooth muscles act involuntary, scientists say. Cardiac muscle cells make up the heart and are responsible for pumping blood throughout the bodies of

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Retrieved Text: A myocyte (also known as a muscle cell) is the type of cell found in muscle tissue.
Myocytes are long, tubular cells. They develop from myoblasts to form muscles in a process called myogenesis.
There are various specialized forms of myocytes: cardiac, skeletal, and smooth muscle cells. They have different structures. The striated or striped cells of cardiac and skeletal muscles are called muscle fibers.
Cardiomyocytes are the muscle fibres which form the chambers of the heart. They have a single central nucleus. Skeletal muscle fibers help support and move the body. They usually have peripheral nuclei.
Smooth muscle cells control involuntary movements such as the peristalsis contractions in the oesophagus and stomach.
↑ Scott, W; Stevens, J; Binder-Macleod, SA (2001). "Human skeletal muscle fiber type classifications.". Physical Therapy 81 (11): 1810–1816. PMID 11694174. Archived from the original on 2015-02-13. https://web.archive.org/web/20150213021358/http://ptjournal.apta.org/content/81/11/1810.full.
↑ "Does anyone know why skeletal muscle fibers have peripheral nuclei, but the cardiomyocytes not? What are the functional advantages?". ResearchGate.

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Retrieved Text: <anatomy> Tissue specialised for contraction. See twitch muscle, catch muscle: Cardiac muscle (heart muscle) is a striated but involuntary muscle responsible for the pumping activity of the vertebrate heart. The individual muscle cells are joined through a junctional complex known as the intercalated disc and are not fused together into multinucleate structures as they are in skeletal muscle. Skeletal muscle is a rather non-specific term usually applied to the striated muscle of vertebrates that is under voluntary control. The muscle fibres are syncytial and contain myofibrils, tandem arrays of sarcomeres. Smooth muscle is muscle tissue in vertebrates made up from long tapering cells that may be anything from 20-500m long. Smooth muscle is generally involuntary and differs from striated muscle in the much higher actin/myosin ratio, the absence of conspicuous sarcomeres and the ability to contract to a much smaller fraction of its resting length. Smooth muscle cells are found particularly in blood vessel walls, surrounding the intestine (especially the gizzard in birds) and in the uterus. The contractile system and its control resemble those of motile tissue cells (for example fibroblasts, leucocytes) and antibodies against smooth muscle myosin will cross react with myosin from tissue cells, whereas antibodies against skeletal muscle myosin will not.

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Retrieved Text: Cardiac muscle groups have to be happy to plan, and also the excitation is realized by sending electric signals. The heart body microscopic cells are “syncytial,” which signifies they are interconnected by membranes with electronically synchronized gap junctions. Mobile membranes often known as “sarcolemma” encompass cardiac myocytes and “are brimming with mitochondria to present the secure way to obtain ATP required to preserve cardiac contraction.” 1 The autonomic central nervous system control buttons the cardiac muscular tissue, which long term contract better than smooth muscle tissue. Cardiac muscle tissue contain property of both skeletal and even muscle. The your muscles have important contractions like skeletal versions, which mandate a whole lot of electrical energy. At the same time, they really are “myogenic,” which signifies they do not really need to have concerned activation to contract, just as some comfortable muscle. Even if the contractions could be modified by outward stimuli, they really cheap essay writing service are organically begun by inherent devices. Cardiac fabric have routine and specific body cells, which can include autorhythmic tissues, which effortlessly blaze behavior potentials or electric signs at individual frequencies. These tissues come in the cardiac conduction process, which Tamarkin explain as “the program of power signaling that instructs these muscle mass skin cells to contract.” 2 Although, the ones that commitment for the speediest rate are located in an element of the most suitable atrium called the sinoatrial node (S-A node). The membranes from the microscopic cells factor 3 or more styles of voltage-gated ion channels, which all develop

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Retrieved Text: b. Its cells usually form concentric circles around osteonic canals. Canaliculi connect them.
c. It is an active tissue that heals rapidly.
12. Blood a. Blood is composed of cells suspended in fluid.
b. Blood cells are formed by special tissue in the hollow parts of certain bones.
1. General characteristics a. Muscle tissue contracts, moving structures that are attached to it.
b. Three types are skeletal, smooth, and cardiac muscle tissues.
2. Skeletal muscle tissue a. Muscles containing this tissue usually attach to bones and are controlled by conscious effort.
b. Cells or muscle fibers are long and threadlike, containing several nuclei, with alternating light and dark cross-markings.
c. Muscle fibers contract when stimulated by nerve impulses, then immediately relax.
3. Smooth muscle tissue a. This tissue of spindle-shaped cells, each with one nucleus, is in walls of hollow internal organs.
b. Usually it is involuntarily controlled.
4. Cardiac muscle tissue a. This tissue is found only in the heart.
b. Cells, each with a single nucleus, are joined by intercalated disks and form branched networks.
c. Cardiac muscle tissue is involuntarily controlled.
1. Nervous tissue is in the brain, spinal cord, and peripheral nerves.
2. Neurons a. Neurons sense changes and respond by transmitting nerve impulses to other neurons or to muscles or glands.
b. They coordinate, regulate, and integrate body activities.
3. Neuroglial cells a. Some of these cells bind and support nervous tissue.
b. Others carry on phagocytosis.
c. Still others connect neurons to blood vessels.
d. Some are involved in cell-to-cell communication.
1. Joints such as the elbow, shoulder, and knee contain considerable amounts of cartilage and loose connective tissue. How does

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Retrieved Text: Muscle Cells require a signal from the brain via nerve cells in order to make muscles move. The nerve cell releases acetylcholine onto the receptors of the muscle cell, which causes sodium to flow into the cell, which triggers a contraction. Smooth muscle, or involuntary muscle, does not necessarily rely on these electrical signals, and cardiac muscle has a special property where a signal to one cell might set off a contraction in many cells nearby, which is very helpful for pumping blood.
How do skeletal muscles move bones?
What is a Muscle Cell?
What does a muscle cell look like?
I dont know why a muscle cell can depolarize, or is it only in the cardiac muscle it does this. Plz explain. If its a special type of nueron I can understand.
I have a pulled muscle in my right thigh.
I got it yesterday at soccer conditioning and we’re having a game (just for fun) tonight at 7, another conditioning Tuesday the 12th, and then tryouts from 13-15! I need to get rid of it by Tuesday and should I go to the game if I can barely run?
I pulled a muscle in my calf today and it hurts really bad when I run. I have a basketball tryout tomorrow and I need it to be better. How can I do this? And I dont want to hear an answer like rest or just wait it out. I need help and now.
Why is repolarization important for action potentials in muscle cells?
How is the structure of muscle tissue related to its

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Retrieved Text: Muscle is one of the four primary tissue types. There are three types of muscle tissue: skeletal muscle, cardiac muscle, and smooth muscle. The three muscle types have some properties in common. They all exhibit excitability as their plasma membranes change their electrical states (depolarization) and send an electrical signal in a wave-like pattern called an action potential along the entire length of the skeletal muscle cell membrane. Skeletal muscle depends on the nervous system to work properly. This is referred to as voluntary motion. In contrast, the nervous system influences the activity of cardiac and smooth muscle to a lesser degree. On the other hand, both cardiac muscle and smooth muscle can respond to other stimuli, such as catecholamines (epinephrine and norepinephrine) from the blood, hormones and local stimuli.
Myoepithelium and myofibroblasts are specialized types of epithelium and fibroblasts, respectively, that have contractile ability. Myoepithelial cells are often located in and around glands where extracellular product produced by the epithelial cells needs to be moved by contractile action towards the duct system. Myofibroblasts are often seen in healing wounds and assist in maturation and contraction of the granulation tissue (immature fibrous connective tissue) as it matures and contracts.

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Retrieved Text: Smooth muscle is represented from the stomach wall.
Smooth muscle tissue is defined as a non-striated muscle tissue comprising involuntary contractile elements surrounding tissues and structures where contraction is part of normal function. The main cell type in smooth muscle tissue is the smooth muscle cell, which similar to myocytes in skeletal and cardiac muscle, predominatly contains actin and myosin proteins. Parenchymal smooth muscle cells are homogenous and tightly arranged together as larger muscular layers that can propagate movement. Parenchymal smooth muscle typically surrounds and forms an integrated part of the respiratory, gastrointestinal and urogenital tract. The main component of the uterus is also smooth muscle tissue, which allows for contraction and normal function at parturition (child birth). Smooth muscle is also a vital component of the vasculature, where more heterogeneous smooth muscle cells are located around blood vessels to control the flow of blood. Histologically, smooth muscle cells exhibit a fairly large cytoplasm with indistinct borders and have single blunt-ended oval nuclei.

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Retrieved Text: The tissue with loose arrangement of cells and the cells are scattered in an extracellular matrix are called connective tissue This non living matrix consists of a web of fibers. These fibers are embedded in a homogenous ground substance. This substance may be liquid, jelly like or solid. The nature of this – extracellular material determines the functional properties of the various.
Connective tissues mainly bind and support other tissues. In most cases, the substance of the matrix is secreted by the cells of the connective tissue. The major types of connective tissues are loose connective tissues, adipose tissue. fibrous tissues, cartilage, bone, and blood.
They Five strong, flexible fibers of collagens. These fibers are interwoven with fine, elastic, and reticular fibers. The collagens make the loose connective tissue elastic. So it makes the loose connective tissues an excellent binding tissue. .They bind epithelia to underlying tissues. They are also used as packing material to hold organ.
Adipose tissue is a type of loose connective tissue that store lipid. These cells accumulate in large numbers to.form fats.
cells osteocytes lie within lacunae. The matrix surrounds them. This matrix avily impregnated with calcium phosphate. It makes this kind of tissue hard. ey are ideally suited for the functions of suppOrt and protection.
d is a connective tissue. It has fluid called plasma. Plasma suspends initialized red and white blood cells and platelets. Blood transports various tances throughout the bodies of animals.
m sin. There are three types of muscles tissue in the vertebrate body: skeletal mu cie, cardiac muscle, muscle.
(a)keletal muscles: Skeletal muscles

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Retrieved Text: Parts Of Skeletal Muscle skeletal muscle definition & functionskeletal muscle also called voluntary muscle in vertebrates most mon of the three types of muscle in the body skeletal muscles are attached to bones by tendons and they produce all the movements of body parts in relation to each other unlike smooth muscle and cardiac muscle skeletal muscle is under voluntary control similar to cardiac muscle however skeletal muscle is striated its.skeletal musclethe cells are fed oxygen and nutrients like sugar and minerals and can grow into skeletal muscle that can be harvested within a few weeks — jacob bunge wsj "startup producing cell grown meat raises new funding " 16 july 2018 noviochok causes involuntary contraction of all skeletal muscles.
Parts Of Skeletal Muscle skeletal muscles and muscle groups david darling introduction there are more than 600 skeletal muscles in the human body which to her account for about 40 percent of a person s weight skeletal muscles are also called voluntary muscles because unlike the other two types of muscle in the body smooth muscle and cardiac muscle they are under conscious control. human skeletal system human skeletal system the internal skeleton that serves as a framework for the body this framework consists of many individual bones and cartilages there also are bands of fibrous connective tissue—the ligaments and the tendons—in intimate relationship with the parts of the skeleton this article is concerned primarily with the gross structure and the function of the skeleton of the. muscle diagram muscle the body diagrams 744×1054 diagram muscle the

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Retrieved Text: Human Myocardial Pericytes: Multipotent Mesodermal Precursors Exhibiting Cardiac Specificity.
Title Human Myocardial Pericytes: Multipotent Mesodermal Precursors Exhibiting Cardiac Specificity.
Perivascular mesenchymal precursor cells (i.e. pericytes) reside in skeletal muscle where they contribute to myofiber regeneration; however, the existence of similar microvessel-associated regenerative precursor cells in cardiac muscle has not yet been documented. We tested whether microvascular pericytes within human myocardium exhibit phenotypes and multipotency similar to their anatomically and developmentally distinct counterparts. Fetal and adult human heart pericytes (hHPs) express canonical pericyte markers in situ, including CD146, NG2, PDGFRβ, PDGFRα, αSMA, and SM-MHC, but not CD117, CD133 and desmin, nor endothelial cell (EC) markers. hHPs were prospectively purified to homogeneity from ventricular myocardium by flow cytometry, based on a combination of positive- (CD146) and negative-selection (CD34, CD45, CD56, and CD117) cell lineage markers. Purified hHPs expanded in vitro were phenotypically similar to human skeletal muscle-derived pericytes (hSkMPs). hHPs express MSC markers in situ and exhibited osteo- chondro-, and adipogenic potentials but, importantly, no ability for skeletal myogenesis, diverging from pericytes of all other origins. hHPs supported network formation with/without ECs in Matrigel cultures; hHPs further stimulated angiogenic responses under hypoxia, markedly different from hSkMPs. The cardiomyogenic potential of hHPs was examined following 5-azacytidine treatment and neonatal cardiomyocyte co-culture in vitro, and intramyocardial transplantation in vivo. Results indicated cardiomyocytic differentiation in a small fraction of hHPs. In conclusion, human myocardial pericytes share certain phenotypic and developmental similarities with their skeletal muscle homologs, yet exhibit different antigenic, myogenic, and angiogenic properties. This is the first example of an anatomical restriction

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Retrieved Text: Muscle cells—whether the skeletal muscles in the arms or legs, the smooth muscles that line the digestive tract and other organs, or the cardiac muscle cells in the heart—work by contracting. Skeletal muscle cells are comprised of thousands of contracting units known as sarcomeres. The proteins actin (thin filament) and myosin (thick filament) are the major components of the sarcomere. These units perform work by moving structures closer together through space; in the skeletal muscles, they pull parts of the body through space relative to each other (for example, when you walk or swing your arms).
To visualize how a sarcomere works, try the following: Interlace the fingers of your two hands with the palms facing toward you (represents actin, myosin); push the fingers together so that the overall length from one thumb to the other is decreased (sarcomere length decreases). And from there, realize that any object attached to either thumb would be pulled through space as the fingers move together (sliding filament theory).

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Retrieved Text: muscular strength; brawn: It will take a great deal of muscle to move this box.
power or force, especially of a coercive nature: They put muscle into their policy and sent the marines.
verb (used with object), mus·cled, mus·cling.
Informal. to force or compel others to make way for: He muscled his way into the conversation.
to strengthen or toughen; put muscle into.
Informal. to accomplish by muscular force: to muscle the partition into place.
Informal. to force or compel, as by threats, promises, influence, or the like: to muscle a bill through Congress.
verb (used without object), mus·cled, mus·cling.
Informal. to make one's way by force or fraud (often followed by in or into).
Informal. (of a machine, engine, or vehicle) being very powerful or capable of high-speed performance: a muscle power saw.
3. power, vigor, might, force.
I can see the implant in there, and see where the muscle is snatching that implant up.
Experts suggest that we need to think of self-control as a “muscle”; something we can train in order to increase our willpower.
Guys with a lot of muscle sometimes find it hard to hold up all that weight.
In fact, research has shown that hitting the weights without fuel can lead to the breakdown of muscle.
Appearance of a small portion of muscle under a moderate magnification.
The other two parts are the opposite ends, and are commonly called the origin and insertion of the muscle.
Broom's eyes opened, and instantly every muscle and nerve in his hard-trained body tensed for action.
late 14c., from Middle French muscle "muscle, sinew" (14c.) and directly from Latin musculus "a muscle,"

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Retrieved Text: SMN protein deficiency in spinal muscular atrophy (SMA) may lead to gastrointestinal (GI) dysfunction by shrinking the smooth muscle in the bladder and altering specific cells in the colon, according to a mouse study.
The study, “Smooth muscle atrophy and colon pathology in SMN deficient mice,” was published in the American Journal of Translational Research.
Unlike respiratory weakness and its associated muscle wasting, studies of SMA have rarely focused on GI problems, which are commonly observed in this disease.
Besides direct innervation of motor nerve cells to smooth muscle cells, nerve impulses may reach the GI tract through a type of cells called interstitial cells of Cajal (ICC). These cells are involved in the contraction and stimulation of smooth muscle cells, including those of the colon.
Aiming to address whether the enteric (gut) nervous system and ICCs may be vulnerable to SMN protein deficiency, researchers used a mouse model of SMA, in which the SMN protein is produced at high levels in the brain and spinal cord; low levels in the cardiac muscle, skeletal muscle, kidney, and lower GI tract; and absent in the upper GI tract, liver, and spleen.
These mice live longer than those with global SMN deficiency and, as a result, may be useful in studies of protein restoration in the central nervous system, according to the researchers.
Measurements conducted at 30 weeks — these animals’ average lifespan — revealed impaired feces excretion as well as smaller bladder mass compared with healthy, or wild-type, animals used as controls. In contrast, body weight was similar between SMA mice and controls.
SMA

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Retrieved Text: A type of striated muscle found specifically in the heart or myocardium.
A structure specific to cardiac muscle formed from gap junctions and desmosomes that allow cardiac muscle cells to contract in a coordinated fashion.
The term for a muscle cell. Applies to skeletal muscle, cardiac muscle and smooth muscle.
The tube like organelle present in skeletal muscle and cardiac muscle that coordinates contraction of the cell.
Modified cardiomyocytes that propagate electrical signals through the cardiac muscle of the myocardium allowing coordinated contraction.
The basic functional unit of striated muscle that is composed of myofilaments.
The organelle that is responsible for the storage and release of calcium into the cytosol of the myofiber.
A type of striated muscle responsible for voluntary movement.
Non-striated muscle that is responsible for involuntary movement within several organ systems.
Invaginations of the sarcolemma (cell membrane) into the cell that allows for the conduction of depolarization impulses from the outside of the cell to around the sarcomeres.

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Retrieved Text: Cells of the human body exhibit three main types of movements, namely, amoeboid, ciliary and muscular.
Amoeboid Movement: Some specialised cells in our body exhibit amoeboid movement, e.g. macrophages and leucocytes. Amoeboid movement is facilitated by pseudopodia formed by the streaming of protoplasm (as in Amoeba). Cytoskeletal elements are also involved in amoeboid movement.
Ciliary Movement: Ciliary movement occurs in most of our internal tubular organs which are lined by ciliated epithelium. The coordinated movements of cilia in the trachea help us in removing dust particles and some of the foreign substances inhaled along with the atmospheric air. Passage of ova through the female reproductive tract is also facilitated by the ciliary movement.
Muscular Movement: Movement of our limbs, jaws, tongue, etc, requires muscular movement. The contractile property of muscles is effectively used for locomotion and other movements by human beings and majority of multicellular organisms. Locomotion requires a perfect coordinated activity of muscular, skeletal and neural systems.
Skeletal Muscles: Skeletal muscles are closely associated with the skeletal components of the body. They have a striped appearance under the microscope and hence are called striated muscles. As their activities are under the voluntary control of the nervous system, they are also known as voluntary muscles. They are primarily involved in locomotory actions and changes of body postures.
Visceral Muscles: Visceral muscles are located in the inner walls of hollow visceral organs of the body like the alimentary canal, reproductive tract, etc. They do not exhibit striation and are smooth in appearance. Hence, they are called smooth muscles (nonstriated muscle). Their activities

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Retrieved Text: Species Reactivity: Tested in human. Shows a broad species reactivity.
Positive Control: Blood vessels in all tissues, smooth muscle or leiomyosarcoma.
Specificity: This monoclonal antibody is highly specific to actin from smooth muscles. This MAb does not stain cardiac or skeletal muscle; however, it does stain myofibroblasts and myoepithelial cells. In most cases of rhabdomyosarcoma, this antibody yields negative results whereas anti-muscle specific actin and myogenin are positive. Leiomyosarcomas are positive only with anti-muscle specific actin and anti-smooth muscle actin and are negative with anti-myogenin.

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Retrieved Text: The muscles of the head and neck perform many important tasks, including movement of the head and neck, chewing and swallowing, speech, facial expressions, and movement of the eyes. These diverse tasks require both strong, forceful movements and some of the fastest, finest, and most delicate adjustments in the entire human body.Producing the body’s ability to close the mouth, bite, and chew food, the muscles of mastication move the mandible relative to the rest of the skull. These muscles, including the masseter and temporalis, elevate the jaw forcefully during chewing and gently during speech.
The Neck Muscles, Facial Muscles and more..
The motion of the muscles of the neck are divided into four categories: rotation, lateral flexion, flexion, and hyperextension. Rotation describes the action of moving the head from side to side, lateral motion brings the ear to the shoulder, flexion moves the chin to the chest (as in looking down), and hyperextension moves the neck so that the head tilts upward.
Bad Posture: Keeping your neck, arms, and shoulders still for extended periods will affect your muscles. For example, it almost always leads to neck stiffness if you work on a computer all day long.
Injury: An injury resulting from a collision, automobile accident, or sports accident that may make your head to jerk around forcefully is more likely to cause stiffness. This may even damage the ligaments in your neck.
Muscle Spasm: You experience a muscle spasm when your nerves signal your muscles to contract. A spasm in the neck may lead to stiffness.
Injury- Bones and muscles can be

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Retrieved Text: The cell, has many pathways to avoid a process called Apoptosis. In contrast to necrosis, which is a form of traumatic cell death that results from acute cellular injury, apoptosis, in general, confers advantages during an organism’s life cycle. For example, the differentiation of fingers and toes in a developing human embryo occurs because cells between the fingers apoptose; the result is that the digits are separate. Unlike necrosis, apoptosis produces cell fragments called apoptotic bodies that phagocytic cells are able to engulf and quickly remove before the contents of the cell can spill out onto surrounding cells and cause damage. But many cells, can avoid this natural pathway and keep on proliferating, growing… CAN YOU REMEMBER SOMETHING LIKE THIS?
YEAP, CANCER…. Cancer cells have the skill to runaway from apoptosis. One of the main «roads» to follow it is a pathway called: The Akt/PKB signaling pathway. Akt/PKB is a pathway in cell signaling.
Proteins involved include AKT (also known as “protein kinase B”, PKB) and phosphoinositide 3-kinase (PI3K).
As you can see on the picture, there are several molecules that naturaly follow some activating/inhibiting pathawys. This complex phosphorylates many highly significant substrates. Akt indirectly activates (not phosphorylates) mTOR, which lies at the heart of growth regulatory pathways.
Akt also phosphorylates Bad (a pro-apoptotic protein,which in its non-phosphorylated state, promotes apoptosis) which sequesters it and keeps it out of action, promoting cell survival.
Exercise training vs Muscle gaining and loss….
How can we built muscle? How do we lose it????
Looking into several degenerative muscular diseases ( Cancer, Diabetes, Heart Disease, Hypertension….) that

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Retrieved Text: Congenital heart disease (CHD) represents the most prevalent inborn anomaly. Only a minority of CHD cases is attributed to genetic causes, suggesting a major role of environmental factors. Nonphysiological hypoxia during early pregnancy induces CHD, but the underlying reasons are unknown. We found that cells in the mouse heart tube are hypoxic, while cardiac progenitor cells (CPCs) expressing ISL1 in the secondary heart field are normoxic. In ISL1+ CPCs, induction of hypoxic responses caused CHD by repressing Isl1 and activating Nkx2.5, resulting in decreased cell proliferation and enhanced cardiomyocyte specification leading to CHD. Mechanistically, hypoxia-induced arrest of Isl1+ CPC proliferation is due to complex formation of HIF1α with the Notch effector HES1 and the protein deacetylase SIRT1 at the Isl1 gene. Our results indicate that spatial differences in oxygenation of the developing heart serve as signals to control CPC expansion and cardiac morphogenesis. We propose that physiological hypoxia coordinates homeostasis of CPCs, providing mechanistic explanations for some nongenetic causes of CHD.
Cardiomyocytes in the adult heart show a decline of differentiated functions and acquisition of immature, “embryonic” properties under various disease processes, which seems to protect cells from hypoxia by reduction of ATP consumption. Cardiomyocyte dedifferentiation in mice depends on the OSM receptor leading to the release of multiple cytokines including Reg3b, which is required for efficient homing of macrophages to the damaged myocardium. In a search for posttranscriptional regulatory processes controlling cardiomyocyte dedifferentiation, we identified miRNAs that suppress the FGFR and OSMR pathways, which are instrumental for the control of postnatal cardiomyocyte proliferation and dedifferentiation.
In contrast

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Retrieved Text: The mammalian esophageal musculature is unique in that it makes a transition from smooth to skeletal muscle, with most of this process occurring after birth. In order to better understand the mechanisms that control esophageal musculature development, we investigated the roles in this process of the paired box transcription factor, PAX7, a principal regulator of skeletal myogenic progenitor cells. Previous studies showed that Pax7 is important for determining the esophageal muscle composition.
We characterized the postnatal development of the esophageal musculature in Pax7 −/− mice by analyzing morphology, muscle composition, and the expression of markers of myogenesis, cell proliferation, and apoptosis. Pax7 −/− mice displayed megaesophagus with a severe defect in the postnatal developmental process whereby esophageal smooth muscle is replaced by skeletal muscle. Pax7 −/− esophagi have substantially reduced skeletal muscle, most likely due to diminished proliferation and premature differentiation of skeletal muscle precursor cells. This impaired the proximal-to-distal progression of skeletal myogenesis and indirectly affected the patterning of the smooth muscle-containing portion of the esophageal musculature.
Postnatal patterning of the esophageal musculature appears to require robust, PAX7-dependent cell proliferation to drive the proximal-to-distal progression of skeletal myogenesis. This process in turn influences distal smooth muscle morphogenesis and development of the mature pattern of the esophageal musculature.
The musculature of the esophagus controls passage of food into the stomach by waves of peristaltic contractions. The lower esophageal sphincter (LES) is a bundle of smooth muscles at the distal end of the esophagus, where it meets the stomach. During swallowing, tonic smooth muscles of the LES relax briefly in

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Retrieved Text: Smooth Musculature - want to learn more about it?
Smooth muscle is a type of tissue found in the walls of hollow organs, such as the intestines, uterus and stomach. You can also find smooth muscle in the walls of passageways, including arteries and veins of de cardiovascular system. This type of involuntary non-striated muscle is also found in the tracts of the urinary, respiratory and reproductive systems. In addition to that, you can find smooth muscle in the eyes, where it acts to change the size of the iris and the shape of the lens. The skin is also contains smooth muscle which allows hair to raise in response to cold temporatures or fear.
The smooth muscle cell is 3-10 µm thick and 20-200 µm long. The cytoplasm is homogeneously eosinophilic and consists mainly of myofilaments. The nucleus is located in the center and takes a cigar-like shape during contraction. The cell membrane forms small pouch-like invaginations into the cytoplasm (caveolae) which are functionally equivalent to the T-tubules of the skeletal musculature. The smooth muscle cells are anchored to the surrounding connective tissue by a basal lamina.
The smooth muscle fibers group in branching bundles. As opposed to skeletal muscle fibers these bundles do not run strictly parallel and ordered but consist in a complex system. Thus the cells can contract much stronger than striated musculature. The actin filaments are stretched between dense bodies in the cytoplasm and attachment plaques at the cell membrane. The myosin filaments lie between the actin filaments. Furthermore intermediate filaments such as desmin

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Retrieved Text: HPA013331 Strong cytoplasmic positivity was displayed in heart myocytes. Small intestine, smooth and skeletal muscle cells exhibited weak cytoplasmic staining. Remaining normal tissues were negative.
HPA039262 Smooth muscle cells, a subset of skeletal muscle cells and myoepithelial cells showed moderate cytoplasmic positivity. Heart muscle displayed strong immunoreactivity. Remaining normal tissues were weakly stained or negative.
CAB033884 Neuronal cells, respiratory epithelium, Leydig cells, epididymis, adrenal gland, muscle tissues, fallopian tubes and squamous epithelium showed weak to moderate nuclear and ytoplasmic positivity. Other normal tissues were in general negative.

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Retrieved Text: Skeletal muscle forms the muscle's attached to the skeleton, which move the limbs and other body parts. Its cells are long, striated, and multinucleate. Skeletal muscle fibers are subject to voluntary control. Connective tissue coverings (endomysium, perimysium, and epimysium) enclose and protect the muscle fibers and increase the strength of skeletal muscles. Skeletal muscles make up the muscular system (Figure 6.1).
Smooth muscle cells are uninucleate, spindle-shaped, and arranged in opposing layers in the walls of hollow organs. When they contract, substances (food, urine, a baby) are moved along internal pathways. Smooth muscle control is involuntary (Figure 6.2).
Cardiac muscle cells are striated, branching cells that fit closely together and are arranged in spiral bundles in the heart. Their contraction pumps blood through the blood vessels. Control is involuntary (Figure 6.3).
The sole function of muscle tissue is to contract or shorten. As it contracts, it causes movement, maintains posture, stabilizes joints, and generates heat.
The multinucleate cylindrical skeletal muscle fibers are packed with unique organelles called myofibrils (Figure 6.4). The banding pattern (striations) of the myofibrils and the cell as a whole reflects the regular arrangement of thin (actin-containing) and thick (myosin) filaments within the sarcomeres, the contractile units composing the myofibrils (Figure 6.5).
Each myofibril is loosely enclosed by a specialized ER, called the sarcoplasmic reticulum (SR), which plays an important role in storing and releasing calcium ions. Calcium ions are the final "trigger" for muscle fiber contraction.
All skeletal muscle cells are stimulated by motor neurons. When the neuron releases a neurotransmitter (acetylcholine), the permeability of the sarcolemma changes,

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Retrieved Text: Somites form during embryonic development and give rise to various cell and tissue types, such as skeletal muscles, ribs, vertebrae, brown fat and skin of the back. We have transcriptionally profiled human presomitic and somitic mesoderm, which has improved our knowledge on this critical process and enabled us to efficiently derive human somite cells from pluripotent stem cells in a dish. We are now using a similar strategy to study different stages of human developmental myogenesis to improve our understanding of myogenic specification in vivo and enhance myogenic cell derivation in vitro.
The developmental status of human pluripotent stem cell (hPSC) derived skeletal muscle cells is not well defined. By using directed differentiation and RNA sequencing, we are are identifying targets to mature HPSC derived muscle to fetal and adult satellite cells.
We reprogrammed DMD patient fibroblasts to DMD-hiPSCs and devised a correction strategy applicable to the majority of DMD patients. Using CRISPR/Cas9, we removed exons 45-55 to restore the dystrophin reading frame in DMD-hiPSCs and demonstrated that directed differentiation of these hiPSCs to skeletal and cardiac muscle restored dystrophin expression in vitro and in vivo.
The functional and therapeutic potential of human fetal, adult, and hPSC derived skeletal muscle progenitor cells (SMPCs) in vivo is not known. We are identifying the most engraftable cell type, signaling factors, and niche components to increase the potential of cell based therapy using SMPCs. This work will be combined with CRIPSR/Cas9 gene editing to develop personalized approaches for patients with muscle disease.

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Retrieved Text: Margaret Buckingham was presented as a newly elected member to the National Academy of Sciences on 28 April 2012. Over the course of her career, Dr Buckingham made many seminal contributions to the understanding of skeletal muscle and cardiac development. Her studies on cardiac progenitor populations has provided insight into understanding heart malformations, while her work on skeletal muscle progenitors has elucidated their embryonic origins and the transcriptional hierarchies controlling their developmental progression.
Dr Margaret Buckingham, a much-respected investigator who has made many significant contributions to our understanding of skeletal muscle and cardiac development, was elected to the National Academy of Sciences in 2011 and presented on 28 April, 2012. Dr Buckingham is Professor in the Department of Developmental Biology at the Pasteur Institute in Paris. She has been awarded many prestigious distinctions including that of Officier de la Légion d’Honneur and Officier de l'Ordre National du Mérite, to name but two.
Dr Buckingham’s early studies involved the cloning and characterization of actin and myosin genes from cardiac and skeletal muscle [1–4]. She has made seminal contributions to our understanding of cardiac development. She identified the second heart field  and showed its important contribution to the poles of the heart. These cardiac progenitors are regulated by a distinct genetic network and in this context, Dr Buckingham has worked on the role of fibroblast growth factor (FGF) signaling in the formation of the outflow tract and pharyngeal arteries . Her studies of cardiac development revealed that that two cell lineages contribute to the myocardium . Lineage studies also

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Retrieved Text: Genetic Testing - Glycogenosis Type 0 (Glycogen storage disease type 0) - Genes GYS1 and GYS2.
Glycogenosis type 0 (Glycogen storage disease type 0) - Genes GYS1 or GYS2.
The type 0 Glycogen (also known as GSD 0) is a disorder caused by the body's inability to form glycogen. This disease has two types: GSD 0 muscle, where the formation of glycogen in the muscles deteriorate, and GSD 0 liver, where glycogen formation in the liver deteriorates.
Signs and symptoms of muscle GSD 0 usually begin in early childhood. Often, those affected manifest pain and muscle weakness , or syncope after moderate physical activity, such as climbing stairs. Loss of consciousness that occurs with fainting usually lasts up to several hours. Some individuals have muscular GSD 0 arrhythmia, known as long QT syndrome. In all individuals affected by such capacity deteriorates heart to pump blood effectively and increases the risk of cardiac arrest and sudden death, especially after physical activity. Sudden cardiac death may occur in childhood or adolescence in people with muscular GSD 0.
Meanwhile, people with GSD 0 liver, often show signs and symptoms of the disease in childhood. People with this type have hypoglycemia after fasting. Signs of hypoglycemia are evident when affected infants start to sleep through the night and stop feeding during it. These children show lethargy, pallor and nausea. During episodes of fasting, concentrations of ketones in the blood can increase, leading to ketosis. Often these signs and symptoms of hepatic GSD 0 improve the short term when foods and sugar levels in the

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Input Text: Answer the following question given this paragraph: 

6.2 The Cell Cycle The cell cycle is an orderly sequence of events. Cells on the path to cell division proceed through a series of precisely timed and carefully regulated stages. In eukaryotes, the cell cycle consists of a long preparatory period, called interphase. Interphase is divided into G1, S, and G2 phases. Mitosis consists of five stages: prophase, prometaphase, metaphase, anaphase, and telophase. Mitosis is usually accompanied by cytokinesis, during which the cytoplasmic components of the daughter cells are separated either by an actin ring (animal cells) or by cell plate formation (plant cells). Each step of the cell cycle is monitored by internal controls called checkpoints. There are three major checkpoints in the cell cycle: one near the end of G1, a second at the G2–M transition, and the third during metaphase.


Q: What consists of these five stages: prophase, prometaphase, metaphase, anaphase, and telophase?

 Choices:

- evolution

- germination

- meiosis

- mitosis

A:

Target Text: mitosis

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Retrieved Text: Meiosis is the process by which gametes are made. In this process, we begin with a 4n cell (double the normal amount of DNA), and we will end up with 4 non-identical haploid (n) daughter gametes, after 2 divisions. There are 6 stages within each of the divisions; Prophase, Prometaphase, Metaphase, Anaphase, Telophase and Cytokinesis. In this article, we will look at all the stages of meiosis in addition to its significance in diseases.
Firstly the nuclear envelope disintegrates and the chromosomes begin to condense. Spindle fibres appear which will be important for successful division of the chromosomes.
Now the spindle fibres attach to the chromosomes at a points along the chromosomes called centromeres. While this is happening the chromosomes continue to condense.
Fig 2 – Image of prometaphase I.
Next, homologous (Maternal and Paternal versions of the same chromosome) chromosomes align along the equator of the cell and a process called random assortment occurs here – this is when maternal and paternal chromosomes line up randomly align themselves on either side of the equator, this leads to genetic diversity among offspring.
To further increase the genetic diversity, homologous chromosomes exchange parts of themselves such that one chromosome contains both maternal and paternal DNA. This process is known as crossing over, and the points at which this occurs on a chromosome are refund to as chiasmata.
Here each of the homologous chromosomes get pulled towards opposite poles of the cell as the spindle fibres retract to divide the DNA between the two cells which will be formed.
Fig 4 – Image of Anaphase

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Retrieved Text: Mitosis is the process by which one cell divides into two genetically identical daughter cells. There are several stages: Interphase, Prophase, Metaphase, Anaphase, Telophase (& cytokinesis). Mitosis is a key component of cell growth and repair.

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Retrieved Text: Lulú. “El GIF De La Semana: Mitosis En Tiempo Real.” Esceptica, 22 Jan. 2014, esceptica.org/2014/01/19/el-gif-de-la-semana-mitosis-en-tiempo-real/.
Mitosis and Meiosis sound very similar, but while they share some similar concepts they are two different biological terms. What is Mitosis? Mitosis is cell division creating two “daughter” cells. Daughter cells have the same number of chromosomes and the same kind of chromosomes as the parent cell. What is Meiosis? Meiosis is creating four “daughter” cells that have half of the chromosomes as the parent cell.
While Mitosis and Meiosis both create daughter cells they make two different kinds. Mitosis creates diploid cells or cells that have 23 chromosomes. While meiosis makes haploid cells or gametes which are your reproductive cells such as sperm in males and eggs in females.
Mitosis exists in six different stages each stage doing something different inside of the cell undergoing mitosis.
Interphase: This stage is when the cell is only preparing for Mitosis or Meiosis(Interphase happens in both). This is also where a cell spends most of its life.
Prophase: Prophase is the “first” stage where the nuclear membrane and the nucleus disappear, chromosomes condense and the mitotic spindles form.
Metaphase: This stage is when the duplicated chromosomes line up at the center of the cell. Fun fact this is called the metaphase plate.
Anaphase: Anaphase is when the duplicated chromosomes separate into two identical groups and move towards opposite ends of the cell.
Telophase: This is the second to last stage where membranes form around the two groups of chromosomes at different ends to produce the nuclei in the daughter cells.

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Retrieved Text: A phosphorylated epitope is differentially expressed at the kinetochores of chromosomes in mitotic cells and may be involved in regulating chromosome movement and cell cycle progression. During prophase and early prometaphase, the phosphoepitope is expressed equally among all the kinetochores. In mid-prometaphase, some chromosomes show strong labeling on both kinetochores; others exhibit weak or no labeling; while in other chromosomes, one kinetochore is intensely labeled while its sister kinetochore is unlabeled. Chromosomes moving toward the metaphase plate express the phosphoepitope strongly on the leading kinetochore but weakly on the trailing kinetochore. This is the first demonstration of a biochemical difference between the two kinetochores of a single chromosome. During metaphase and anaphase, the kinetochores are unlabeled. At metaphase, a single misaligned chromosome can inhibit further progression into anaphase. Misaligned chromosomes express the phosphoepitope strongly on both kinetochores, even when all the other chromosomes of a cell are assembled at the metaphase plate and lack expression. This phosphoepitope may be involved in regulating chromosome movement to the metaphase plate during prometaphase and may be part of a cell cycle checkpoint by which the onset of anaphase is inhibited until complete metaphase alignment is achieved.

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Retrieved Text: During the prophase stage of cell division, chromosomes begin to condense, coil and fold, making them visible under a light microscope. When the duplicated chromosomes continue to coil, the chromosomes are shortened and thickened to a more visible state.... prophase I - meiosis term refers to the first phase of meiosis I, which together with meiosis II results in the reductive cell division only occurring gametes. Prophase can be further divided into a number of stages: leptotene zygotene, pachytene, diplotene, diakinesis.
Go back to prophase 1 and write in alleles for your chromosomes. The drawing below shows what they would look like before they are copied during interphase. Make sure that you write in the alleles on the copied sister chromatids too! a A. B b g G . R r H h. D d. Now, show the alleles of one gene crossing over in one set of homologous chromosomes. Circle the set you chose. Now follow along and... During the prophase stage of cell division, chromosomes begin to condense, coil and fold, making them visible under a light microscope. When the duplicated chromosomes continue to coil, the chromosomes are shortened and thickened to a more visible state.
Prophase – The replicated chromosomes condense into compact rods. Each rod Each rod consists of two sister chromatids joined at the centromere or the chromosome.
☆ These questions asked the reader to describe and draw the cell when it was in the telophase and the late prophase stages of mitosis. ☆ During meiotic prophase in females, chromosomes condense and pair to

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Retrieved Text: The stage in mitosis and in the second meiotic division when the centromere splits and the chromatids separate and move to opposite poles.
The stage of the first meiotic division when the two halves of a bivalent chromosome separate and move to opposite poles.
With respect to the results listed in Table 2, the orange and grape juices of the five food companies, at both exposure times considered, induced significant formation of mitotic spindle changes, represented in this study by colchicine metaphase and anaphase and telophase bridges, proving to be genotoxic, and chromosome breaks, characterized by the formation of micronuclei.
To determine if aurora A kinase (AAK) plays a post-metaphase role in Drosophila S2 cell division, AAK was knocked down by RNA interference (RNAi), and microtubule (MT) intensity in the spindle midzone during late anaphase was quantified (Fig.
1 (b) IVM, in vitro maturation; GVBD, germinal vesicle breakdown; MI, Metaphase 1; AI, Anaphase 1; TI, TelophaseI; MII, MetaphaseII; SEM, standard error of the mean.
The damaged chromosomes, in the form of acentric chromatids or chromosome fragments, lag behind in anaphase when centric elements move towards the spindle poles.
Several chromosomal aberrations (CA's) like chromosomal break, stickiness, laggard, and multipolar anaphase have been formed.
It delivers the two groups of chromosomes to positions adjacent to the polar furrows midway between pairs of plastids in anaphase and a phragmoplast is constructed in the midzone (Fig.
10 and 50 [micro]g/ml number of prophases and telophases generally increases by prolonging treatments, and the number of metaphases and anaphases decreases.
This can be seen from the simulation results in To

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Retrieved Text: It's meiosis that gives us the male and female reproductive cells known as the egg and sperm. In meiosis, two cell divisions take place, which produces four genetically unique cells with half the number of chromosomes as the parent cell.
I have a brother. He has brown hair and brown eyes. I don't look much like him because I have blonde hair and blue eyes. We share the same parents, yet we don't share all of the same genes. For instance, my brother got the gene for brown eyes, and I got the one for blue eyes. While there are a number of things to consider, it's basically meiosis that gave me different genes than my brother.
Meiosis is a type of cell division that produces gametes. The term gametes is just the scientific way of saying sperm and eggs. During meiosis, one parent cell divides into two cells and then divides again to make a total of four cells. During all of this dividing, genes get shuffled around, and the number of chromosomes gets cut in half. So the result of meiosis is four genetically unique cells, or gametes, with half the number of chromosomes as the parent cell. Now that we kind of have an overview, let's take a closer look at how this works.
Before we go too far, I want to point out something. Meiosis is different than mitosis, which you might have learned about in a different lesson. In mitosis, we see body cells divide to form identical body cells. For example, skin cells

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Retrieved Text: Spindle assembly during meiosis I in primary Drosophila spermatocytes.
Recording of GFP-alphaTubulin84B in primary Drosophila spermatocytes reveals the location of two diametrically opposed asters around the nuclear envelope before meiosis I. Upon nuclear envelope breakdown, indicated by the sudden entry of GFP signal into the nuclear area, spindle assembly takes place. Intranuclear microtubules form a bipolar structure that connect the asters at the two poles. Extranuclear microtubules derived from both asters expand toward the cortex and converge in the equatorial plane of the cell.
Recording of GFP-alphaTubulin84B in primary Drosophila spermatocytes reveals the behaviour of intra- and extranuclear microtubules during the first stages of spindle assembly. Later, at anaphase I, intranuclear microtubules contacting the chromosomes shorten, whereas extranuclear microtubules expand towards the cortex and converge at the position where the cytokinesis furrow will form.
Spindle assembly and chromosome behaviour during meiosis I in primary Drosophila spermatocytes.
Recording of GFP-alphaTubulin84B (in yellow) and Histone2-YFP (in red) reveal microtubule and chromosome behaviour during spindle assembly in meiosis I. During prometaphase I bivalent chromosomes interact with astral microtubules and congress to the metaphase I plate.
Recording of GFP-alphaTubulin84B (in yellow) and Histone2-YFP (in red) reveal microtubule and chromosome behaviour during spindle assembly and division in meiosis I. During anaphase I homolog chromosomes separate and migrate to opposite poles as kinetochore microtubules shorten.
Spindle assembly and central spindle formation during meiosis I in primary Drosophila spermatocytes.
Recording of GFP-alphaTubulin84B in a primary Drosophila spermatocyte from the onset of meiosis I to telophase I. The different sets of microtubules can be tracked all throughout the cell cycle. Note

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Retrieved Text: We have identified a maize homologue of yeast MAD2, an essential component in the spindle checkpoint pathway that ensures metaphase is complete before anaphase begins. Combined immunolocalization of MAD2 and a recently cloned maize CENPC homologue indicates that MAD2 localizes to an outer domain of the prometaphase kinetochore. MAD2 staining was primarily observed on mitotic kinetochores that lacked attached microtubules; i.e., at prometaphase or when the microtubules were depolymerized with oryzalin. In contrast, the loss of MAD2 staining in meiosis was not correlated with initial microtubule attachment but was correlated with a measure of tension: the distance between homologous or sister kinetochores (in meiosis I and II, respectively). Further, the tension-sensitive 3F3/2 phosphoepitope colocalized, and was lost concomitantly, with MAD2 staining at the meiotic kinetochore. The mechanism of spindle assembly (discussed here with respect to maize mitosis and meiosis) is likely to affect the relative contributions of attachment and tension. We support the idea that MAD2 is attachment-sensitive and that tension stabilizes microtubule attachments.
The spindle checkpoint is a surveillance pathway that ensures metaphase is complete before anaphase begins (Elledge, 1996; Rudner and Murray, 1996; Wells, 1996; Hardwick, 1998). The components of the spindle checkpoint were originally identified in budding yeast as nonessential genes that allowed cells to divide even in the absence of fully formed spindles. At least seven yeast genes have been identified in the pathway, including Bub1, 2, and 3, Mad1, 2, and 3, and Mps1 (Hardwick, 1998). One of the most thoroughly studied spindle checkpoint genes is Mad2, which encodes a highly conserved

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Retrieved Text: 0:15Skip to 0 minutes and 15 secondsWelcome to the next video for 'Cancer in the 21st century; The Genomic Revolution'. Previously we've looked at cells, their components, and how they work and are controlled by genes under normal conditions. So we can now move on to thinking about how cells grow and divide and how these processes are normally regulated, before we begin to consider how these processes are interrupted in cancer cells. So what is the cell cycle? In most eukaryotic cells there is a series of events which must occur in a particular order which ultimately results in the cell's division and duplication or replication.
0:58Skip to 0 minutes and 58 secondsThe phases or steps in the cycle are controlled by checkpoints, which prevent the cell cycle progressing to subsequent stages until all the necessary molecular events have occurred. Cells begin the cycle by entering interphase. Interphase is where the cell prepares for division by growing and duplicating it's DNA. Interphase can be further broken down into three discrete phases-- G1, S, and G2. In G1, normal cellular functions occur, as well as cell growth where organelle and cytoskeletal components increase. S is the synthesis stage. Nuclear DNA replicates producing two identical copies of each chromosome. During the G2 phase, the cell continues to grow and prepare for mitosis and cell division.
1:58Skip to 1 minute and 58 secondsMitosis-- or the M-phase-- can be further subdivided into prophase, metaphase, anaphase, and telophase. During prophase, the chromosomes become visible and condense. Each identical copy of a single

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Retrieved Text: Paul Andersen compares and contrasts mitosis and meiosis. He shows how you can count cells in various phases of mitosis to construct a cell cycle pie chart.
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Updated Mitosis Video. The Amoeba Sisters walk you through the reason for mitosis with mnemonics for prophase, metaphase, anaphase, and telophase.
(OLD VIDEO) Mitosis: The Amazing Cell Process that Uses Division to Multiply!
This video has been updated! Visit: https://youtu.be/f-ldPgEfAHI Music used with permission from Adrian Holovaty (http://www.youtube.com/adrianholovaty).
https://www.mometrix.com/studyguides/teas/ Get free help for the ATI TEAS test with our ATI TEAS Science review video about mitosis.
LO QUE NECESITAS SABER PARA PASAR TU EXAMEN DE GED 2019 FACILMENTE.
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Meiosis and mitosis in all its glory!

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Retrieved Text: Animal Cell Mitosis - CELLS alive!
Events during Mitosis. Interphase: Cells may appear inactive during this stage, but they are quite the opposite.This is the longest period of the complete cell cycle during which DNA replicates, the centrioles divide, and proteins are actively produced.
Mitosis: Mitosis, a process of cell duplication, or reproduction, during which one cell gives rise to two genetically identical daughter cells. Strictly applied, the term is used to describe the duplication and distribution of chromosomes, the structures that carry the genetic information.
Mitosis - When Cells Split Apart Eventually cells need to duplicate. There are two main methods of replication, mitosis and meiosis.This tutorial will talk about mitosis. The big idea to remember is that mitosis is the simple duplication of a cell and all of its parts.
Mitosis Skit Students should write and perform a skit to show the process of mitosis, using the loose guidelines that follow. These guidelines are intended to help get you started, as well as provide room for the development of a skit that suits your class size, available supplies, and students' creativity.
In this cell division exercise, you drag and drop chromosomes to demonstrate your knowledge of the difference between mitosis and meiosis.
Mitosis definition is - a process that takes place in the nucleus of a dividing cell, involves typically a series of steps consisting of prophase, metaphase, anaphase, and telophase, and results in the formation of two new nuclei each having the same number of chromosomes as the parent nucleus.
You'll find out how cells divide, how organisms grow, and

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Retrieved Text: The process of meiosis creates 4 haploid gamete cells from a diploid cell. In animals these gametes are called eggs and sperm and in plants they are called eggs and pollen. For meiosis to occur it must go through two divisions, Meiosis I and Meiosis II. During Meiosis, the cell goes through the same stages as Mitosis (Interphase, Prophase, Metaphase, Anaphase, and Telophase/Cytokinesis), but it goes through these phases twice, but with some minor differences.
Creates 4 haploid gamete cells from a diploid cell.
At this point the DNA is in its chromatin form and the DNA replicates.
Homologous Chromosomes (matching chromosomes from mom and dad) join up together and exchange share genetic information. Happens during Prophase I of meiosis.
Matching chromosomes from mother and father. They are the same size, shape and carry genes for the same traits.
The chromosomes line up down the middle along with their homologous pair.
The homologous chromosomes pull apart from one another and move toward opposite poles.
Chromosomes are now at separate poles, nuclear membranes start to form around the 2 sets of chromosomes, and the chromosomes start to unwind back into chromatin. Cytokinesis occurs and the two cells split. These two cells are haploid at this point since each cell contains only 1 of each homologous pair. The next 4 phases occur to each of these cells.
Notice that we skip interphase this time around because there is no replication of DNA between Meiosis I and Meiosis II.
At this point the chromosomes reorganize and the nuclear membranes start to dissolve again. Sister chromatids are joined by

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Retrieved Text: DNA replication generally suggests producing two complete DNA lengths for every single girl cell associated with 5 Teaching Dna Replication instead of the one parent cell. Ahead of the mobile team, its genetics inside the nucleus is launched by an molecule to interrupt the hydrogen bonds involving the bottoms, causing two halves of the genetics. The uninhibited nucleotides inside the nucleus securities using the bottoms of both lengths. Securities with T alone while H with G, ultimately causing specific matches for both lengths.
You will find four stages in mobile division, or mitosis (typical cell division, meiosis varieties gender cells).
Prophase: Coupling of chromosomes happens and pursuing reproduction, the guardian cell has two comprehensive units. Two posts are created because the nucleus disappears.
Metaphase: Position of the chromosomes are at the equator involving the two posts.
Anaphase: The chromosomes separate towards each rod. Cell membrane department starts.
Telophase: Look of nuclei are at each rod and membrane breaks. Two cells get equivalent chromosomes.
Feel free to download the Photos under 5 Teaching Dna Replication content for free. Suport us by sharing this Photos to your family.
Publish at October 23, 2018 By: Lucas R. Cox in Cell Category.
Tagged with: bioteach dna replication, dna replication teaching resources, ideas for teaching dna replication, teachers domain dna replication, teaching dna replication, .

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Retrieved Text: Short Video on The Cell Cycle!
Your life began when a sperm, Verne the Sperm, met the love of his life, Meg the Egg!
The sperm gave the egg a package that was full of DNA.
You started out as a tiny, humble single cell called a zygote. From that single cell, you grew to the wonderful person you are today!
IN YOUR BODY... Millions of cells divide every second.
​ Your body has ~100 trillion cells.
That single cell, became you with your 100 trillion cells! That is a lot of cell division!
​This type of cell division is called MITOSIS.
Mitosis is Divided Into 4 Parts. Think... Paco Made A Taco!
1) Prophase - The "P" in Paco, stands for Prophase!
2) Metaphase - The "M" in Made, stands for Metaphase!
3) Anaphase - The "A" in the phrase Paco Made A Taco, stands for Anaphase!
4) Telophase - The "T" in Taco, stands for Anaphase!
Mitosis is only one small part (~10%) of the whole cell cycle.
​The rest of the cell cycle is called INTERPHASE.
Why do cells undergo mitosis in the first place?
Just like mitosis is subdivided into its 4 different parts (Prophase, Metaphase, Anaphase and Telophase), Interphase also has subdivision! Interphase is made up of the 3 parts, G1, S-Phase and G2!
G1 is also known as Gap 1.
G1, Is where the cell cycle BEGINS! It is a period of rapid growth of the cell. It duplicates its organelles and proteins to get ready for the next steps of the cell cycle!
S-Phase is also known as Synthesis.
S-Phase, is where the genetic material gets duplicated or copied.

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Retrieved Text: A single unattached kinetochore can delay anaphase onset in mitotic tissue culture cells (Rieder, C.L., A. Schultz, R. Cole, G. Sluder. 1994. J. Cell Biol. 127:1301–1310). Kinetochores in vertebrate cells contain multiple binding sites, and tension is generated at kinetochores after attachment to the plus ends of spindle microtubules. Checkpoint component Mad2 localizes selectively to unattached kinetochores (Chen, R.-H., J.C. Waters, E.D. Salmon, and A.W. Murray. 1996. Science. 274:242–246; Li, Y., and R. Benezra. Science. 274: 246–248) and disappears from kinetochores by late metaphase, when chromosomes are properly attached to the spindle. Here we show that Mad2 is lost from PtK1 cell kinetochores as they accumulate microtubules and re-binds previously attached kinetochores after microtubules are depolymerized with nocodazole. We also show that when kinetochore microtubules in metaphase cells are stabilized with taxol, tension at kinetochores is lost. The phosphoepitope 3f3/2, which has been shown to become dephosphorylated in response to tension at the kinetochore (Nicklas, R.B., S.C. Ward, and G.J. Gorbsky. 1995. J. Cell Biol. 130:929–939), is phosphorylated on all 22 kinetochores after tension is reduced with taxol. In contrast, Mad2 only localized to an average of 2.6 out of the 22 kinetochores in taxol-treated PtK1 cells. Therefore, loss of tension at kinetochores occupied by microtubules is insufficient to induce Mad2 to accumulate on kinetochores, whereas unattached kinetochores consistently bind Mad2. We also found that microinjecting antibodies against Mad2 caused cells arrested with taxol to exit mitosis after ∼12 min, while uninjected cells remained in mitosis for at least 6 h, demonstrating that Mad2 is necessary

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Retrieved Text: Mitotic cyclin-dependent kinase with their cyclin partners (cyclin:Cdks) are the master regulators of cell cycle progression responsible for regulating a host of activities during mitosis. Nuclear mitotic events, including chromosome condensation and segregation have been directly linked to Cdk activity. However, the regulation and timing of cytoplasmic mitotic events by cyclin:Cdks is poorly understood. In order to examine these mitotic cytoplasmic events, we looked at the dramatic changes in the endoplasmic reticulum (ER) during mitosis in the early Drosophila embryo. The dynamic changes of the ER can be arrested in an interphase state by inhibition of either DNA or protein synthesis. Here we show that this block can be alleviated by micro-injection of Cyclin A (CycA) in which defined mitotic ER clusters gathered at the spindle poles. Conversely, micro-injection of Cyclin B (CycB) did not affect spatial reorganization of the ER, suggesting CycA possesses the ability to initiate mitotic ER events in the cytoplasm. Additionally, RNAi-mediated simultaneous inhibition of all 3 mitotic cyclins (A, B and B3) blocked spatial reorganization of the ER. Our results suggest that mitotic ER reorganization events rely on CycA and that control and timing of nuclear and cytoplasmic events during mitosis may be defined by release of CycA from the nucleus as a consequence of breakdown of the nuclear envelope.
Funding: Funding provided by National Institute of Health, Minority Biomedical Research Support (MBRS) R25-GM059298Z, BMJ, ASE, Genentech Foundation MS Dissertation Scholarship, grant #3179555, JDM, National Institute of Health, Support of Competitive Research (SCORE) Program, 5SC2 GM098229-02, BR, ZJB, AQS. The funders had

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Retrieved Text: I love this science video. Creative and innovative. Great job ladies and gents. We need more of these to show that science really is fun.
Oh, and I want one of those hats for the next conference!!! How cool is that!
Enjoy, smile and Happy New Year to everyone!
Hello? Hello? Baby, you called. I can’t hear a thing.
I have got not service in the laboratory.
I have got no time for talking. Baby, can’t you see?
I am trying to study some biochemistry.
When the chromosomes condense then we call it prophase.
And when they line up then it is called metaphase.
When they pull apart then we call it anaphase.
And when they divide into two cells that is telophase.
Stop calling. Stop calling. I don’t wanna talk anymore.
I have a test that I am studying for.
It’s all in the chromosome.
And when those cells explode they call it apoptosis.
Different than necrosis. Not caused by osmosis.
It’s dangerous when the cell begin undergoing anoikis.
Then there’s metastasis. Cell death is so tasteless.
That you have a purine paired with a pyrimidine.
Which is twisted around like a spiral staircase.
Copying, copying like in vivo but much faster.
I got my genes from the lab thermocycler.
This entry was posted in Education and tagged Educational, General Information by Roberta Estes. Bookmark the permalink.
Great video! Girls w/Test tubes!
Love the chromosome fascinator! I think I need one of those.

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Retrieved Text: Indirect immunofluorescence was used to determine the distribution of calmodulin in the mitotic apparatus of rat kangaroo PtK2 and Chinese hamster ovary (CHO) cells. The distribution of calmodulin in PtK2 cells was compared to the distribution of tubulin, also as revealed by indirect immunofluorescence. During mitosis, calmodulin was found to be a dynamic component of the mitotic apparatus. Calmodulin first appeared in association with the forming mitotic apparatus during midprophase. In metaphase and anaphase, calmodulin was found between the spindle poles and the chromosomes. While tubulin was found in the interzonal region throughout anaphase, calmodulin appeared in the interzone region only at late anaphase. The interzonal calmodulin of late anaphase condensed during telophase into two small regions, one on each side of the midbody. Calmodulin was not detected in the cleavage furrow. In view of the differences in the localization of calmodulin, tubulin, and actin in the mitotic apparatus, experiments were designed to determine the effects of various antimitotic drugs on calmodulin localization. Cytochalasin B, an inhibitor of actin microfilaments, had no apparent effect on calmodulin or tubulin localization in the mitotic apparatus of CHO cells. Microtubule inhibitors, such as colcemid and N2O, altered the appearance of tubulin- and calmodulin-specific fluorescence in mitotic CHO cells. Cold temperature (0 degrees C) altered tubulin-specific fluorescence of metaphase PtK2 cells but did not alter calmodulin-specific fluorescence. From these studies, it is concluded that calmodulin is more closely associated with the kinetichore-to-pole microtubules than other components of the mitotic apparatus.

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Score: 53.959938
Retrieved Text: Here you have a list of opinions about Anaphase and you can also give us your opinion about it.
You will see other people's opinions about Anaphase and you will find out what the others say about it.
Anaphase (from the Greek ἀνά, "up" and φάσις, "stage"), is the stage of mitosis or meiosis when chromosomes are split and the sister chromatids move to opposite poles of the cell.
Anaphase accounts for approximately 1% of the cell cycle's duration. It begins with the regulated triggering of the metaphase-to-anaphase transition. Metaphase ends with the destruction of B cyclin. B cyclin is marked with ubiquitin which flags it for destruction by proteasomes, which is required for the function of metaphase cyclin-dependent kinases (M-Cdks). Anaphase starts when the anaphase promoting complex marks an inhibitory chaperone called securin with ubiquitin for destruction. Securin is a protein which inhibits a protease known as separase. The destruction of securin unleashes separase which then breaks down cohesin, a protein responsible for holding sister chromatids together. The centromeres are split, and the new daughter chromosomes are pulled toward the poles. They take on a V-shape as they are pulled back.
While the chromosomes are drawn to each side of the cell, the non-kinetochore spindle fibers push against each other, in a ratcheting action, that stretches the cell into an oval.
Once anaphase is complete, the cell moves into telophase.
In the image below, you can see a graph with the evolution of the times that people look for Anaphase. And below it, you can see how many pieces of news

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Retrieved Text: 8: Metaphase | Chromosomes line up in the middle of the cell.
9: Anaphase | Centromeres divide and Chromosomes move towards opposite poles.
10: Telophase | Nuclear envelope forms at each pole. Chromosomes uncoil and the spindle fibers dissolves.
11: Cytokinesis | The cytoplasm divides and produces two daughter cells that are identical to the original cell.

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Retrieved Text: The ability of all life to replicate itself for future generations originates in the reproduction of cells.
All cells arise from other cells.
Cells have a limited life span.
During cell division, one cell becomes split into 2 cells. The original cell is called the PARENT CELL. The 2 cells resulting from the division are called DAUGHTER CELLS.
– The cell cycle is the entire lifespan of a cell, starting with its production from a previous parent cell and ending with its division into 2 new daughter cells.
– Compared to the rest of the cells’ life, cell division is a brief and distinct stage in the cells’ life.
– The cell cycle is composed of an orderly sequence of phases that are controlled by the DNA of the cells’ nucleus.
– It is composed of an INTERPHASE where the cell is growing larger and replicating its DNA. Then there is nuclear division, called MITOSIS, that has 4 stages; prophase, metaphase, anaphase and telophase. Mitosis ends with the division of the cell into 2 separate daughter cells.
– Interphase is not part of cell division. It is a stage when the cell is growing, metabolizing and replicating its DNA.
– All cells spend most of their lives (about 90%) in Interphase. Some cells never leave the stage of interphase.
– Interphase provides enough time for the cell to grow large enough to eventually divide into 2 daughter cells.
– Interphase is divided into 3 stages; G1 phase, S phase and G2 phase.
– The cell experiences growth in volume and carries on its normal processes.
– If centrioles (small

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Rank: 22
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Retrieved Text: How Do Cells Keep From Growing Too Large?
Cells keep from growing too large by undergoing cell division, also known as mitosis. The mitosis process involves a cell splitting off into two daughter cells that contain the same DNA as the original cell.
Mitosis occurs because the outside part of a cell cannot grow as fast as the inside part of the cell. The cell exterior is necessary for transporting oxygen and food to the cell interior. When a cell grows, the interior develops at a quicker rate than the exterior of the cell. As such, the interior develops to the point where the exterior of the cell can no longer transport food and oxygen at a sustainable rate. To remedy this, the cell undergoes mitosis to make the transport of nutrients more efficient through two smaller cells.
The beginning stage of mitosis is called prophase. In prophase, a cell's chromosomes condense and structures called centrioles begin to move in opposite directions within the cell. The next stage is metaphase, which results in the chromosomes forming a line within the middle of the cell.
After metaphase, the chromosomes are pulled apart by spindle fibers and pulled in opposite directions of the cell. The separated chromosomes are genetically identical and are referred to as chromatids. The final stage is telophase, which involves the formation of a nuclear envelope and the completion of two new cells containing the same DNA.

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Rank: 23
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Retrieved Text: Explain why cloning begins with a stem cell.
a. Answer the following questions about the cell membrane.
ii. Describe the role of lipid molecules in making the cell membrane semipermeable.
Answer the questions concerning movement through cell membranes. How does osmosis differ from diffusion? . v. 3. i. What substances in the human body are transported by diffusion? iv. Describe facilitated diffusion. What is dialysis? Describe how it is used in an artificial kidney.3 Movement through Cell Membranes a.Mitochondria Lysosomes Peroxisomes Microfilaments & Microtubules Centrosome Cilia & Flagella Vesicles Nuclear Envelope Nucleolus Chromatin IV. In what direction do the molecules of solute move in diffusion? ii. vi. When does diffusion stop? iii.
b. i. What provides the necessary force for this process? iii. ii. In active transport. molecules move from regions of ___________________________ concentration to regions of ______________________________ concentration. What substances are transported by this membrane? d. i. Compare active transport to facilitated diffusion. Answer the questions concerning active transport. Label the tonicity of the solution in each drawing. ___________________________ ________________________ Answer the questions concerning the accompanying diagram. What transport mechanism is illustrated here? ii. Below are three drawings of a red blood cell in solutions of varying tonicity. . What is the source of this force? iv. How are molecules transported across the cell membrane? v. ________________________ c.
e. ii. i. What organelles are involved? iii. The process by which cells develop differences in structure and function is ________________________________. e. What mechanism is illustrated in this drawing? ii. . prophase metaphase anaphase telophase c. Answer these questions concerning cell differentiation.

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Rank: 24
Score: 49.102825
Retrieved Text: We’ve all been there before. It’s a few weeks to the exam, we’re starting to panic and we’re starting to prepare ourselves for a mad few weeks of late nights, textbooks and caffeine… #cramming. So with exams looming and the stress beginning to set in, I have 2 questions: how do we actually learn faster? What’s the best way to revise without cramming?
The aim of this phase is to get an overview of the topic as quickly as possible. Don’t waste your time reading your text book and making detailed notes on every single topic and sub topic. Instead, I use a simple method to get a quick overview. First, I skim read through the text, making sparse notes whilst going along. If I struggle to understand a topic or point I try and write a quick summary of what I’ve read or make a note of that specific section and move on. You’ll come back to this hurdle later. Second, I make a simple mind-map for each topic. Detail is not necessarily important here, although you may pull out a few key facts and/or quotations. This tests your own ability to summarize and break up a topic into themes or its constituent parts.
The second part of revision is completing practice questions. Elevate’s research demonstrates that this is single-handedly the best form of preparation. The simple reason for this is that by doing a lot of practice questions, a student is very quickly able to identify what it is they know and what it is they

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Rank: 25
Score: 48.04591
Retrieved Text: Centromere-associated protein-E (CENP-E) is an essential mitotic kinesin that is required for efficient, stable microtubule capture at kinetochores. It also directly binds to BubR1, a kinetochore-associated kinase implicated in the mitotic checkpoint, the major cell cycle control pathway in which unattached kinetochores prevent anaphase onset. Here, we show that single unattached kinetochores depleted of CENP-E cannot block entry into anaphase, resulting in aneuploidy in 25% of divisions in primary mouse fibroblasts in vitro and in 95% of regenerating hepatocytes in vivo. Without CENP-E, diminished levels of BubR1 are recruited to kinetochores and BubR1 kinase activity remains at basal levels. CENP-E binds to and directly stimulates the kinase activity of purified BubR1 in vitro. Thus, CENP-E is required for enhancing recruitment of its binding partner BubR1 to each unattached kinetochore and for stimulating BubR1 kinase activity, implicating it as an essential amplifier of a basal mitotic checkpoint signal.
Successful cellular propagation requires faithful replication and equal segregation of genetic information. Loss or gain of even a single chromosome during meiosis most often results in the production of gametes that are unable to produce viable offspring (for review see Cohen, 2002). Loss or gain of chromosomes during mitotic divisions leads to the production of cells with a DNA content greater or less than 2N, a condition known as aneuploidy, which is a hallmark of cancer cells. Maintenance of ploidy is ensured through action of the mitotic checkpoint, which prevents the transition to anaphase until all chromosomes have made productive, bipolar attachments through their kinetochores to the microtubules of the

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Rank: 26
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Retrieved Text: Within 24 hours, a human cell can divide into two daughter cells that are identical to the original. This cell cycle includes growth of the cell, duplication of the DNA and division of the chromosomes and cell contents. The stages of the cycle -- which occur in both plants and animals -- are called interphase, mitosis and cytokinesis. Kinetochore and nonkinetochore -- also known as interpolar -- microtubules play an important role in the separation of chromosomes and the formation of daughter cells. These microscopic structures are both made from subunits called tubulin, but they have different functions during cell division.
When a cell enters mitosis, a microtubule-based structure called a spindle forms with two poles at either end of the enlarged cell. The chromosomes align along the center of the spindle prior to separation of the chromatids -- half of the duplicated chromosomes. Kinetochore microtubules extend from the spindle poles toward the center of the cell and attach to the chromatids at a structure called the kinetochore. The nonkinetochore microtubules also extend from the spindle toward the center of the cell, but they do not attach to the chromatids. Instead they overlap at the center of the spindle.
During late prophase -- one of the phases of mitosis -- the plate-like kinetochore forms on the duplicated chromosomes. Each chromosome has two kinetochores -- one for each identical sister chromatid -- attached to kinetochore microtubules from opposite poles. Kinetochore microtubules attached to the kinetochore cause the chromosomes to line up along the middle of the spindle. Nonkinetochore microtubules

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Rank: 27
Score: 47.148247
Retrieved Text: Which cartoon shows the correct way for the chromosomes to line up at the metaphase plate during mitosis?
What would happen if one chromosome failed to have microtubules from both poles attach?
One daughter cell would not have a copy of that chromosome.
Diatoms are protists that have rigid glass walls. Based on this you can conclude that they carry out cytokinesis similarly to ______________.
What would happen if a cell were unable to properly condense its chromosomes during prophase?
The chromosomal DNA would be subjected to shearing forces, fragmenting the chromosome.
What would happen if cytokinesis occurred before telophase was completed?
A cell that has just exited the G1 phase of the cell cycle (and will eventually go on to divide) will next enter ___________________.
Chromosomes condense and begin to be visible during _____________.
A number of chemical treatments cause microtubules to fall apart. Colchicine (mitonic inhibitor) is one such drug. What would happen if a dividing cell was treated with colchicine?
What would happen to a cell if it went directly from prophase to anaphase (i.e., it failed to undergo metaphase)?
The daughter cells would probably not get equal numbers of chromosomes.
A chimpanzee bone marrow cell, in prophase of mitosis, contains 48 chromosomes. How many chromatids does it contain?
When do homologous chromosomes pair?
Starting with one cell, how many daughter cells will be formed when meiosis is complete?
Sperm cells and ova can be classified as ______________ cells.
How many pairs of homologous chromosomes are found in human males?
The cellular process by which gametes are formed from specialized nonreproductive cells is ________ .
Crossing over occurs during which stage

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Score: 46.93756
Retrieved Text: Ms. Peggy Nuyens has been teaching for over 35 years. In 1981, She started her career at Stanley Humphries and this year, she will bring her teaching career to a close at SHSS.
Ms. Nuyens worked at several schools including Beaver Valley Middle School and Trail Middle schools and taught everything from PE to spelling to textiles. But from the time she went into teaching, Ms. Nuyens knew that Home Ec was her fit and of all of the subject areas she explored, Foods was her favorite.
In her retirement, Ms Nuyens hopes to spend lots of time with her family, especially her grand daughters, and enjoy this next part of her life. She also said that she will enjoy going to the grocery store, just for fun!
Thanks to Ms Nuyens several generations of students got to discover the world of cooking. Her passion for food and nutrition, as well as her love of her students, will be missed at SHSS.
Thank you, Ms Nuyens, for your years of work, your countless hours of preparation, the care you put into each lesson and all of the great memories you created for our students. We will miss you!
Had a chance to check out some great projects in the Woodwork 9 class of Mr. Don Liszt. These two young ladies, who happened to be cousins, Stefanie and Allison Soukeroff were busy doing some finishing work on their projects had an opportunity to share thier awesome work. Thanks for sharing, ladies!
Posted on June 14, 2018 Leave a comment on Cousin Carpentry Inc.
These

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Rank: 29
Score: 43.543705
Retrieved Text: This image roughly shows a nucleus with chromatin inside of a cell. Interphase is where the DNA is copied.
In metaphase the chromosomes make there way into a single file line through the middle of the cell.
During anaphase the chromosomes are pulled apart and starting the cell division.
Telophase is the final phase of mitosis. this is the stage where the nucleur pore re forms around each of the new cells. now there are 2 cells where there use to be 1.
Which circuit has the largest current?
The circuit with the biggest bulb (180mA) has the largest current.
Which circuit has the smallest current?
The circuit with the long bulb (45mA) has the smallest current.
What is the purpose of the switch in this current?
The purpose of the switch is to turn the light on and off.
When you measure an unknown current, you should start with the meter set to a large current scale and then decrease the scale. Explain the purpose of starting with a higher setting.
You should start with a higher setting because starting with a small setting you can break the amp meter by overloading. It is better to start with a higher setting then working your way through the smaller settings so you can get an accurate reading easier.

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Input Text: Answer the following question given this paragraph: 

Mutations that lead to cancer usually occur in genes that control the cell cycle. These include tumor-suppressor genes and proto-oncogenes.


Q: Mutations that lead to cancer usually occur in genes that control the cell cycle. these include tumor-suppressor genes and what?

 Choices:

- apparition - oncogenes

- proto-oncogenes

- Darkness Oncogenes

- extinction - oncogenes

A:

Target Text: proto-oncogenes

#### Retrieved Documents ####

Rank: 0
Score: 95.822136
Retrieved Text: Cancer causes about one-fifth of the deaths in the United States each year. Worldwide, between 100 and 350 of each 100,000 people die of cancer each year.
Cancer is due to failures of the mechanisms that usually control the growth and proliferation of cells.
During normal development and throughout adult life, intricate genetic control systems regulate the balance between cell birth and death in response to growth signals, growth-inhibiting signals, and death signals.
Cell birth and death rates determine adult body size, and the rate of growth in reaching that size.
In some adult tissues, cell proliferation occurs continuously as a constant tissue-renewal strategy.
Intestinal epithelial cells, for instance, live for just a few days before they die and are replaced; certain white blood cells are replaced as rapidly, and skin cells commonly survive for only 2–4 weeks before being shed.
The cells in many adult tissues, however, normally do not proliferate except during healing processes. Such stable cells (e.g., hepatocytes, heart muscle cells, neurons) can remain functional for long periods or even the entire lifetime of an organism.
The losses of cellular regulation that give rise to most or all cases of cancer are due to genetic damage.
Mutations in two broad classes of genes have been implicated in the onset of cancer: proto-oncogenes and tumor suppressor genes.
Proto-oncogenes are activated to become oncogenes by mutations that cause the gene to be excessively active in growth promotion.
Either increased gene expression or production of a hyperactive product will do it.
Tumor suppressor genes normally restrain growth, so damage to them allows inappropriate growth.
Many of the genes

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Retrieved Text: The structure of DNA can be damaged in a number of ways such as exposure to chemicals or radiation. DNA is very susceptible to damage and if the damage is not corrected, it will subsequently be copied and passed on to daughter cells. Damage can include breaking of the DNA backbone, structural or spontaneous alterations of bases, or incorporation of the incorrect base during replication. Any defect in the genetic code can cause an increased risk of cancer, so the cell has multiple processes in place to catch and correct genetic errors. This helps maintain the integrity and stability of the genome from cell to cell, and from generation to generation.
Certain genes, when mutated, can lead to cancer. Cancer cells proliferate excessively because they are able to divide without stimulation from other cells and are no longer subject to the normal controls on cell proliferation. By definition, cancer cells are able to migrate by local invasion ormetastasis, a migration to distant tissues by the bloodstream or lymphatic system. Over time, cancer cells tend to accumulate mutations.
Mutated genes that cause cancer are termed oncogenes. Oncogenes primarily encode cell cycle-related proteins. Before these genes are mutated, they are often referred to as proto-oncogenes. The first gene in this category to be discovered was src (named after sarcoma, a category of connective tissue cancers). The abnormal alleles encode proteins that are more active than normal proteins, promoting rapid cell cycle advancement. Typically, a mutation in only one copy is sufficient to promote tumor growth and is therefore considered dominant.
Tumor

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Retrieved Text: Normal cell division ft Tumor-suppressor genes normally produce factors that inhibit cell division.
^ Mutant alleles are recessive (both alleles must be mutated to produce excessive cell proliferation).
21.24 Both oncogenes and tumor-suppressor genes contribute to cancer but differ in their modes of action and dominance.
Oncogene Cellular Location Function of Proto-oncogene sis Secreted Growth factor erbB Cell membrane Part of growth-factor receptor erbA Cytoplasm Thyroid hormone receptor src Cell membrane Protein tyrosine kinase ras Cell membrane GTP binding and GTPase myc Nucleus Transcription factor fos Nucleus Transcription factor jun Nucleus Transcription factor bcl-1 Nucleus Cell cycle become incorporated into the viral genome through recombination. Within the viral genome, the proto-oncogene may mutate to an oncogene that, when inserted back into a cell, causes rapid cell division and cancer. Because the proto-oncogenes are more likely to undergo mutation or recombination within a virus, viral infection is often associated with the cancer.
Proto-oncogenes can be converted into oncogenes in viruses by several different ways. The sequence of the proto-oncogene may be altered or truncated as it is being incorporated into the viral genome. This mutated copy of the gene may then produce an altered protein that causes uncontrolled cell proliferation. Alternatively, through recombination, a proto-oncogene may end up next to a viral promoter or enhancer, which then causes the gene to be overexpressed. Finally, sometimes the function of a proto-oncogene in the host cell may be altered when a virus inserts its own DNA into the gene, disrupting its normal function.
Many oncogenes have been identified by experiments in which selected fragments

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Score: 82.93128
Retrieved Text: NHS UK. Predictive gene tests for cancer risk genes.
Available here (Accessed: June 08, 2015).
Cancer is a complex multi-factorial disease; its development is triggered by a combination of genetic and environmental factors. Important hereditary factors include mutations in seven distinct protein groups that encompass proto-oncogenes, tumor suppressor genes, and DNA damage repair components.
Most oncogenes are activated via point mutations, gene amplifications and gene translocations in a proto-oncogene. This results in altered gene expression or protein activity levels (Lodish et al. 2000). However, mutations to another group of proteins, known as tumor suppressors, also play an important role in the development of various cancer types. Mutant tumor suppressor genes are recessive, and therefore both alleles need to be mutated in order to trigger tumor development (in most cases the protein expressed by the unaffected allele is sufficient to control cell growth). This phenomenon has been described by the American geneticist Alfred Knudson under the term “multiple-hit hypothesis”; it suggests that while inheriting one faulty allele will predispose an individual to cancer further “hits” or mutations to the second functioning allele are required to trigger cancer onset.
The inheritance of certain mutant tumor suppressor alleles, such as breast cancer 1, early onset (BRCA1) and breast cancer 2, early onset (BRCA2) mutant alleles, significantly increase the risk of developing breast and ovarian cancers. Actress Angelina Jolie recently made headlines for undergoing preventive surgery after having tested positive for carrying a BRCA gene mutation. Jolie expressed that her mother died of ovarian cancer, while her grandmother and aunt died of breast cancer.

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Score: 82.602
Retrieved Text: A classification for genetic disorders of interest to orthopaedists.
A human novel gene DERPC on 16q22.1 inhibits prostate tumor cell growth and its expression is decreased in prostate and renal tumors.
A mutant form of p135tyk2, an interferon-alpha inducible tyrosine kinase, suppresses the transformed phenotype of Daudi cells.
Allelic loss at the tuberous sclerosis 2 locus in spontaneous tumors in the Eker rat.
Aneuploidy of chromosome 9 and the tumor suppressor genes p16(INK4) and p15(INK4B) detected by in situ hybridization in locally advanced prostate cancer.
Association of a p73 exon 2 G4C14-to-A4T14 polymorphism with risk of squamous cell carcinoma of the head and neck.
Biology of small cell lung cancer.
Combined effects of the p53 and p73 polymorphisms on lung cancer risk.
Different cellular p16(INK4a) localisation may signal different survival outcomes in head and neck cancer.
Dinucleotide polymorphism of p73 gene is associated with a reduced risk of lung cancer in a Chinese population.
Effect of BRCA1 and BRCA2 on the association between breast cancer risk and family history.
Exome sequencing of gastric adenocarcinoma identifies recurrent somatic mutations in cell adhesion and chromatin remodeling genes.
Gene therapy for lung cancer.
Genetic alterations in prostate adenocarcinoma.
Genetic mechanisms of solid tumor oncogenesis.
Genotypic analysis of tumor suppressor genes PTEN/MMAC1 and p53 in head and neck squamous cell carcinomas.
Hereditary prostate cancer in African-American families.
Hereditary renal cell carcinoma in the Eker rat: a unique animal model for the study of cancer susceptibility.
Identification and functional characterization of the human glutathione S-transferase P1 gene as a novel transcriptional target of the p53 tumor suppressor gene.
Identification of p18 INK4c as a tumor suppressor gene in glioblastoma multiforme.
Implication

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Rank: 5
Score: 79.86991
Retrieved Text: PLoS Med. 2008 May 27;5(5):e114. doi: 10.1371/journal.pmed.0050114.
Convergence of mutation and epigenetic alterations identifies common genes in cancer that predict for poor prognosis.
Chan TA1, Glockner S, Yi JM, Chen W, Van Neste L, Cope L, Herman JG, Velculescu V, Schuebel KE, Ahuja N, Baylin SB.
Cancer Biology Program, The Johns Hopkins Kimmel Cancer Center, Baltimore, Maryland, United States of America.
The identification and characterization of tumor suppressor genes has enhanced our understanding of the biology of cancer and enabled the development of new diagnostic and therapeutic modalities. Whereas in past decades, a handful of tumor suppressors have been slowly identified using techniques such as linkage analysis, large-scale sequencing of the cancer genome has enabled the rapid identification of a large number of genes that are mutated in cancer. However, determining which of these many genes play key roles in cancer development has proven challenging. Specifically, recent sequencing of human breast and colon cancers has revealed a large number of somatic gene mutations, but virtually all are heterozygous, occur at low frequency, and are tumor-type specific. We hypothesize that key tumor suppressor genes in cancer may be subject to mutation or hypermethylation.
Here, we show that combined genetic and epigenetic analysis of these genes reveals many with a higher putative tumor suppressor status than would otherwise be appreciated. At least 36 of the 189 genes newly recognized to be mutated are targets of promoter CpG island hypermethylation, often in both colon and breast cancer cell lines. Analyses of primary tumors show that 18 of these genes are hypermethylated strictly in primary

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Rank: 6
Score: 79.22151
Retrieved Text: Cancer is the most common human genetic disease. The transition from a normal cell to a malignant cancer is driven by changes to a cell’s DNA, also known as mutations. The cells in the human body work together, dividing and reproducing in a strictly controlled and coordinated fashion.DNA replication is an essential part of cell division whereby the cell makes an identical copy of its genome? before it divides.Mistakes or ‘mutations’ can occur during DNA replication, changing the genome of the new cell being made.Most of these mistakes are quickly repaired by the cell’s machinery, but sometimes mistakes are missed and the change in the DNA remains.If these mutations occur in genes that control growth (proto-oncogenes and tumour suppressor genes) uncontrolled cell growth can occur, which can lead to tumour formation and cancer Proto-oncogenes encourage the cell to multiply. If these genes become mutated they tell the cell to multiply all the time and are then called oncogenes. Tumour suppressor genes stop the cell from multiplying. If these genes are mutated and stop working, the cells may carry on multiplying. To become cancerous, a cell must acquire mutations in several growth-controlling genes. In families with an inherited faulty gene there may be a pattern of specific types of cancer running in the family. Most people who have relatives with cancer will not have inherited a faulty gene. Cancer mostly occurs in older people. It is a common disease. 1 in 2 people in the UK (50%) will get cancer at some point in their lives. So,

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Rank: 7
Score: 78.212296
Retrieved Text: Deregulated Notch signaling is linked to a variety of tumors and it is therefore important to learn more about the frequency and distribution of Notch mutations in a tumor context.
In this report, we use data from the recently developed Cancer Cell Line Encyclopedia to assess the frequency and distribution of Notch mutations in a large panel of cancer cell lines in silico.
Our results show that the mutation frequency of Notch receptor and ligand genes is at par with that for established oncogenes and higher than for a set of house-keeping genes. Mutations were found across all four Notch receptor genes, but with notable differences between protein domains, mutations were for example more prevalent in the regions encoding the LNR and PEST domains in the Notch intracellular domain. Furthermore, an in silico estimation of functional impact showed that deleterious mutations cluster to the ligand-binding and the intracellular domains of NOTCH1. For most cell line groups, the mutation frequency of Notch genes is higher than in associated primary tumors.
Our results shed new light on the spectrum of Notch mutations after in vitro culturing of tumor cells. The higher mutation frequency in tumor cell lines indicates that Notch mutations are associated with a growth advantage in vitro, and thus may be considered to be driver mutations in a tumor cell line context.
Our understanding of the molecular basis for cancer is rapidly improving, to a large extent owing to the recent progress in DNA sequencing technologies, which now allows the mutational landscape to be explored in a genome-wide manner both

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Rank: 8
Score: 77.02041
Retrieved Text: Click on the targets in the map below to find Elabscience products related to the P53 Signaling Pathway.
P53 has been found most associated with human tumors of all genes. P53 mutations occur in the vast majority of tumor cells and in more than 50% of all malignant tumors. The protein encoded by this gene is a transcription factor that controls the initiation of the cell cycle. Many signals about cellular health are sent to P53 protein and it determines whether the cell enter a division cycle. P53 is a tumor suppressor protein that regulates the expression of a variety of genes, including apoptosis, growth inhibition, cell cycle progression inhibition, differentiation and acceleration of DNA repair, genotoxicity, and aging after cellular stress. Like all other tumor suppressors, P53 gene plays a slowing or monitoring role in cell division under normal conditions. In addition, P53 triggers apoptosis pathways only as a transcription factor which is independent from its activity.

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Rank: 9
Score: 76.93713
Retrieved Text: The etiology of most human cancers is unknown. Genetic inheritance and environmental factors are thought to have major roles, and for some types of cancer, exposure to carcinogens is a proven mechanism leading to tumorigenesis. Sequencing of entire cancer genomes has not only begun to provide clues regarding functionally relevant mutations, but has also paved the way towards understanding the initial exposures leading to DNA damage, repair and eventually to mutation of specific sequences within a cancer genome. Two recent studies of melanoma and small cell lung cancer exemplify what type of information can be gained from cancer genome sequencing.
The origins of human cancers have environmental and hereditary components. Germline mutations of tumor suppressor genes found in cancer predisposition syndromes are prominent examples of inheritance and include well known tumor suppressor genes, such as the retinoblastoma gene (RB), TP53, the breast cancer genes BRCA1 and BRCA2, the adenomatous polyposis coli gene APC, the mismatch repair genes MLH1 and MSH2 and a few others. Although mutations in these genes are very rare in the general population, they confer a high risk for developing the disease. Mutations in this group of genes account for only a small fraction of the excess cancer incidence in familial cancer. For some common cancers with significant aspects of heritability, such as prostate cancer, highly penetrant susceptibility genes are still unknown. For these reasons, attention has now shifted towards ascribing much of the observed familial cancer risk to polygenic models of predisposition in which variant alleles, each conferring a small added risk, cooperate

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Rank: 10
Score: 76.23821
Retrieved Text: MUB1501P – a well-characterized antibody against p53 - Exalpha Biologicals inc.
Although only a fraction of genes in the human genome have a direct association with the induction and development of cancer, two broad gene classes – proto-oncogenes and tumor suppressor genes – have demonstrated a clear link to progression of the disease. These genes encode various proteins involved in regulating cell growth and proliferation, and while gain-of-function mutations in proto-oncogenes give rise to oncogenes which may stimulate uncontrolled cell proliferation and survival, loss-of-function mutations in tumor suppressor genes may also be oncogenic.
p53 is the product of the p53 tumor suppressor gene, and was first discovered in 1979. SDS-PAGE analysis at the time indicated an apparent molecular weight of 53kDa, hence the name. p53 is activated in response to a wide variety of cellular stress signals including DNA damage, hypoxia, nutrient deprivation and oncogene expression, and its primary role is to limit cell proliferation under unfavorable conditions. Although p53 was originally thought to be an oncogene further research demonstrated it to be a tumor suppressor. It is now known to be one of the most commonly mutated tumor suppressor genes in human cancer.
MUB1501P is a mouse monoclonal antibody of isotype IgG2a/kappa, with clone number DO-1. Details of its production were first published in 1992 when Vojtĕsek et al described the hyper-immunization of mice with bacterially-expressed recombinant human wild-type p53 protein, and the subsequent production of hybridoma. The specificity of DO-1 was confirmed by immunoblotting, immunoprecipitation, immunocytochemistry and ELISA using a panel of cell lines with well-characterized homozygous

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Rank: 11
Score: 76.13655
Retrieved Text: © Springer Science+Business Media New York 2017. Cancer can be considered a disease caused by mutations and/or epigenetic changes in tumor suppressor genes and oncogenes that populate the host genome. It is well established that most of the genetic events in cancer result from a series of accumulated, acquired genetic lesions. These genetic events either inactivate tumor suppressor genes or activate oncogenes. With an enhanced understanding of the genetic lesions associated with malignant transformation and progression in a wide variety of human cancers, different therapeutic approaches are being identified. In this regard, gene therapy is emerging as a method of preventive and therapeutic intervention against cancer targeted at the level of cellular gene expression. In this approach, altering the complex cancerous pathophysiologic state is achieved by delivering nucleic acids into cells. These nucleic acids may be genes, portions of genes, oligonucleotides, or RNA. In conventional therapeutics, as in pharmacotherapy, altering a cell or tissue phenotype is accomplished by altering cell physiology or metabolism at the level of protein expression. In contrast, in gene therapy this is accomplished by changing the pattern of expression of genes whose products may correct defects in cellular phenotype.

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Rank: 12
Score: 75.82054
Retrieved Text: My group is interested in signalling pathways that promote colorectal tumorigenesis and we study (i) the alternative splice variant Rac1b overexpressed in tumours, (ii) the effect of activated b-catenin/TCF signalling on splicing, (iii) the effect on splicing of exonic missense mutations diagnosed by our department in colorectal tumour suppressor genes, and (iv) the role of a novel cell-cycle regulating protein that co-immunoprecipitates with cdc5L and Prp19.
Matos, P., Oliveira, C., Velho, S., Gonçalves, V., da Costa, L.T., Moyer, M.P., Seruca, R. and Jordan, P. (2008). B-RafV600E cooperates with alternative spliced Rac1b to sustain colorectal cancer cell survival. Gastroenterology 135, 899-906.
Vieira, L., Sousa, A.C., Matos, P., Marques, B., Alaiz, H., Ribeiro, M.J., Braga, P., da Silva, M.G., Jordan, P. (2006). Three-way translocation involves MLL, MLLT3, and a novel cell cycle control gene, FLJ10374, in the pathogenesis of acute myeloid leukemia with t(9;11;19)(p22;q23;p13.3). Genes Chromosomes Cancer 45, 455-469.
Matos, P., Collard, J. and Jordan, P. (2003). Tumor-related alternative- spliced Rac1b is not regulated by Rho-GDI and exhibits selective downstream signaling. Journal of Biological Chemistry 278, 50442-50448.
Clarke, L.A., Veiga, I., Isidro, G., Jordan, P., Silva Ramos, J., Castedo, S. and Boavida, M.G. (2000). Pathological exon skipping in an HNPCC proband with hMLH1 splice acceptor site mutation. Genes Chromosomes Cancer 29, 367-370.

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Rank: 13
Score: 75.78199
Retrieved Text: "Oncologists here at Moores Cancer Center at UC San Diego Health and elsewhere can often personalize cancer therapy based on an individual patient's unique cancer mutations," said senior author Trey Ideker, PhD, professor of genetics at UC San Diego School of Medicine. "But the vast majority of mutations are not actionable — that is, knowing a patient has a particular mutation doesn't mean there's an available therapy that targets it. The goal of this study was to expand the number of mutations we can pair with a precision therapy."
Most cancers have gene mutations that do one of two things — promote cell growth or prevent cell death. The first type is the target of many therapies, which inhibit cell growth. But it's much harder to develop therapies that restore malfunctioning genes that should be triggering cell death in abnormal cells, known as tumor-suppressor genes.
The researchers first used yeast to quickly and cheaply screen 169,000 interactions between yeast versions of human tumor-suppressor genes and genes that can be inhibited with drugs, sometimes called "druggable" targets. To do this, they deleted each gene one at a time, in combination with another mutation. Those experiments whittled down the best combinations — those lethal to the yeast cells — to a few thousand.
Here's one example of how this information might be useful for doctors and patients: Irinotecan is a drug only indicated by the FDA for use in colon cancer. But this study suggests that this class of drugs should be evaluated for efficacy in any tumor with a mutation

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Rank: 14
Score: 74.79512
Retrieved Text: Whoever studies the DNA of uncontrollably-growing tumor cells finds therein a seemingly wild confusion of mutations: translocations, base pair substitutions and differing sets of chromosomes. The results of the Cancer Genome Project should soon indicate which mutations are critical to the fate of these "cancer clones".
The theory is too simplistic to capture the essence of the story. Why does a normal cell at some point become a cancer cell? In the course of its life, influences from within and without are responsible for ever more points of mutation, areas where the sequence of letters, the sentence structure or even entire chapters in the book of DNA are no longer there in the way that they were written at the beginning. Eventually, it happens – but which mutations are the crucial ones in this transition to the “eternal cell life“ and which determine how fast this cloning proliferates and even migrates into other tissues?
In order to elucidate how, from a rather well-ordered text, a jumble of letters arises, and what meaning errors in individual chapters have, the Cancer Genome Project will sequence the genomes of more than 25,000 cancer patients, among whom are sufferers of about fifty different types of cancer. A mammoth task awaits researchers in Germany, Australia, China, India, Spain, England, the United States and some other participating nations.
Not all mutations in a cancer cell have the same significance. Most of the changes in the DNA code are known as „passenger mutations”. They arise in the course of many cell divisions of the clone, but

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Rank: 15
Score: 74.00194
Retrieved Text: ComprehensiveDx ClearTM is a comprehensive panel for hereditary breast, ovarian, uterine, colorectal, pancreatic, prostate and melanoma cancers.
Some types of cancer have a significant hereditary component and can develop due to a mutation in one of the hereditary cancer predisposition genes. Breast, ovarian, colorectal, endometrial, melanoma, pancreatic, gastric, and prostate cancers are among those with a significant hereditary component.
A family history includes a number of cancer cases of several different types indicating a presence of several hereditary cancer syndromes.
A family history is suggestive of inherited cancer; however the cancer type(s) do not seem to fit a particular hereditary cancer syndrome.
Are you at high risk for Hereditary Cancer Syndromes?
What are the possible benefits of genetic testing with ComprehensiveDx ClearTM?
ComprehensiveDx ClearTM is a comprehensive panel for hereditary breast, ovarian, uterine, colorectal, pancreatic, prostate and melanoma cancers. This next-generation sequencing (NGS) assay analyses point mutations, gross deletions and duplications in the following genes associated with various inherited cancers: APC, ATM, BAP1, BARD1, BMPR1A, BRCA1, BRCA2, BRIP1, CDH1, CDK4, CDKN2A, CHEK2, DICER1, EPCAM (CNV only), FANCC, MLH1, MRE11A, MSH2, MSH6, MUTYH, NBN, PALB2, PMS2, POLD1, POLE, PTEN, RAD50, RAD51C, RAD51D, SDHA, SDHB, SDHC, SDHD, SMAD4, STK11 and TP53. This panel includes emerging genes (such as BARD1, CDK4, DICER1, POLD1) with limited data on their association with hereditary cancer in addition to well-studied cancer predisposing genes. The variants identified by the test are classified according to the guidelines for sequence variant interpretation of the American College of Medical Genetics and Genomics (ACMG). Variant classification categories include pathogenic, likely pathogenic, variant of unknown

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Rank: 16
Score: 73.84812
Retrieved Text: The team, from Johns Hopkins University in Maryland, says this could have major consequences for how genetic analysis is done in humans.
Because of the way DNA is conserved across species, the researchers say their findings - published in the journal Molecular Cell - could be applicable to human genetics, particularly for certain areas of research, such as cancer.
Their research adds new evidence that genomes - the sum of species' genes - operate in an interconnected way so that the removal of a single part could stress the whole system, prompting another part to mutate as a result.
"The deletion of any given gene usually results in one, or sometimes two, specific genes being 'warped' in response. Pairing the originally deleted gene with the gene that was secondarily mutated gave us a list of gene interactions that were largely unknown before."
She says this work "has the potential to transform the field of cancer genetics," noting that it would encourage researchers to have greater scrutiny in genetic analyses, as they could unknowingly ascribe something to a gene they mutated, whereas it could be due to a secondary mutation.
Deletion of one gene causes instability in the genome, prompting another gene to mutate to offset the imbalance.
Hardwick and her team worked with yeast because it is easy to "knock out" or delete any particular gene. They wanted to know whether within a given strain of yeast, each cell has the same genetic sequence as the other cells, as was previously thought.
"We know, for example, that within a given tumor, different cells

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Rank: 17
Score: 73.21047
Retrieved Text: Anderson, Karen Sue Blattman, Joseph N.
Currently, there are few methods available to analyze the evolution of tumor heterogeneity; micro-dissection of tumors only provides information on major species of malignant cells but is unable to detect rare therapy-resistant subclones that have the potential to regenerate tumors. Identification of these rare cells by single-cell isolatio and sequencing is both time-consuming and prohibitively expensive. Recent next-generation deep sequencing studies have demonstrated the clinical relevance of clonal heterogeneity within individual cancers, but currently rapid and cost-effective methods to measure and track the rates of co-occurrences of mutations in cell populations do not exist. Therefore, the development of rapid, flexible, single- cell technologies with the capacity to identify heterogeneous mutations of multiple genes in individual cells within bulk populations is critical for the development of effective targeted therapies that prevent tumor relapse. To overcome this challenge, we propose to adapt novel nanomolecular scaffolds (termed DNA origami) to transfect tumor cells and capture mRNA encoding known-tumor suppressor genes. We propose to test the specificity of these scaffolds in breast tumor cell lines and primary breast tumor with known mutations in p53, PTEN, and PIK3CA genes. This approach will allow the rapid quantitation of genomic diversity and evolutionary order in cells from solid tumors for improved targeting of rare malignant subclones.
A key challenge in cancer therapeutics is the heterogeneity of the cancer cells. Rare mutated cells give rise to resistant cancers, and current methods to identify these rare subpopulations of cells by single-cell isolation and sequencing is both time-consuming and prohibitively expensive. These

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Rank: 18
Score: 73.13396
Retrieved Text: Inheritance of a mutated retinoblastoma gene (Rb*) greatly increases the likelihood of developing the disease.
two hits senescence a state in a cell in which it will not divide again, even in the presence of growth factors apoptosis programmed cell death quickly increase the chance that a cell will become cancerous. Repair genes include those in the DNA-ligase and excision-repair gene families.
Genes Involved in Cell Mortality. A normal cell can only undergo about forty divisions, after which it dies or enters senescence. If a tumor had this limitation it would be very limited in its size, as it would reach its forty divisions relatively quickly. This process is controlled by the enzyme telomerase, which maintains the telomeres (repetitive DNA sequences at the ends of chromosomes that shorten after each round of DNA replication, until they reach a length that causes the cell to die) by not allowing them to shorten. Some cancer cells become immortal as a result of mutations in the telomerase gene, causing the telomeres to be extended indefinitely, allowing the cell to continue dividing without limit. Other mutations affect the process of apoptosis.
Cancer does not usually arise by a single event. Instead, two or more "hits" are needed to convert a well-regulated cell to a cancer cell. This is the case because each cell contains two copies of each gene, one inherited from each parent. Most cancer-causing mutations cause a loss of function in the mutated gene. Often, having only one functional copy is enough to prevent disease. Thus, two mutations are needed.
This can

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Rank: 19
Score: 73.03998
Retrieved Text: Cancer genes and food that fight cancer – Bio-Synthesis, Inc.
Disclaimer: Due to the many posters and program items covered at this meeting and to my personal inability to attend them all I will only list highlights that are of personal interest to me.
Reducing tobacco use, improving diet and physical activity, reducing obesity, and expanding the use of established screening methods is recommended to avoid suffering and death from cancer.
Furthermore, vaccination against human papillomavirus and hepatitis B virus together with minimizing extensive exposure to ultraviolet radiation is recommended to reduce major risk factors of cancer.
More and more evidence has accumulated in recent years indicating that the food a human eats affects her or his risk for developing cancer. Many scientists now estimate that between 30 to 60% of all cancers are caused by environmental factors. Since all of us have to eat the type of food we eat and what lifestyle we have may increase or decrease our risk of developing cancer. In addition, there are many indications that the majority of cancers may be preventable. Altering one’s lifestyle may achieve this goal. However, the range in percentage of these estimates varies depending on which review articles are consulted.
Two out of three humans are resistant to the development of cancer and never get it.
According to George Klein two out of three humans, never get cancer. Klein suggests that resistance genes act at the level of tissue organization in a fashion that this prevents the development of cancer in close to 60% of all humans. Many genetic and

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Rank: 20
Score: 72.49634
Retrieved Text: Mutational analysis of the p21/WAF1/CIP1/SDI1 coding region in human tumor cell lines.
p21/WAF1/CIP1/SDI1 is an important cell-cycle mediator with tumor suppressor gene capabilities, and its inactivation could potentially lead to tumor progression. Because tumor suppressor genes are commonly inactivated by somatic and germline mutations, we analyzed a variety of human tumor cell lines for p21 mutations. We used single-strand conformational analysis and direct sequencing to identify possible mutations in the p21 coding region. Two base-alterations were observed in 41 immortalized human tumor cell lines. A previously reported polymorphism that results in a serine-to-arginine amino-acid substitution at codon 31 was found in 24% (10 of 41) of the tumor cell lines but was also found in 10% (six of 62) of normal parental DNAs tested and 7% (three of 43) of normal DNAs from patients with primary endometrial tumors. Another nucleotide substitution found at codon 80 resulted in the replacement of threonine with methionine. Codon 80 changes were found in 7% (three of 41) of the tumor cell lines (all endometrial) and in 2% (one of 62) of the normal parental DNAs. This change was not found in any of the primary endometrial tumors examined. The biological activity of these base changes was analyzed by using in vitro cyclin-dependent kinase 2-cyclin A kinase assays and calcium phosphate transfections. We observed that wild-type p21 and the p21 variants had similar growth-inhibitory abilities. Thus, our results suggest that mutation of the p21 gene is not prevalent in human tumor cell lines and is not a probable mechanism of inactivation of

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Rank: 21
Score: 72.45154
Retrieved Text: There is a growing body of evidence that epigenetic alterations play a pivotal role in a wide variety of cancers. Epigenetic alterations are changes in gene expression that are independent of changes to the underlying DNA sequence. In other words, genetic mutations change gene sequence while epigenetic changes impact gene expression.
What does gene expression have to do with cancer? Normal gene expression ensures that tumor promoter genes are properly silenced and that tumor suppressor genes are properly active, or expressed. These epigenetic pathways are like master switches that regulate gene expression, and are critical for maintaining normal biological function.
One type of epigenetic “switch” is through DNA acetylation and deacetylation – the addition or removal of acetyl chemical groups to DNA. Abnormal acetylation patterns in DNA can lead to improper epigenetic regulation of oncogenes and tumor suppressor genes, leading to tumor growth, proliferation and potentially metastasis.
A proper balance of acetylation and deacetylation is regulated by histone acetyltransferases (HAT) and histone deacetylases (HDACs) enzymes. HAT and HDAC enzymes act together in opposing roles to regulate the expression of other important genes involved in cell growth, survival and differentiation. HAT enzymes function as epigenetic “writers” by adding acetyl groups to key histone and non-histone proteins, while HDACs have an opposing function as epigenetic “erasers” by removing acetyl groups.
Combination therapies are an integral part of cancer treatment. The combination of mocetinostat (MGCD103) with agents that target other epigenetic pathways has a strong scientific rationale. The strength of the rationale is based on the crosstalk between epigenetic regulatory molecules which are

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Rank: 22
Score: 72.20229
Retrieved Text: Cancer is an abnormal growth of cells. Cancer cells quickly reproduce event without enough space and nutrients. They also grow despite signals sent from the body to stop reproduction. Cancer cells are often shaped differently from healthy cells. They do not work well and can spread to many parts of the body. Tumors, masses, or lesions are names for abnormal growths of tissue that can become cancer. Their growth is not regulated.
Oncology is the branch of medicine that studies the diagnosis and treatment of cancer.
What do the terms benign and malignant mean?
Tumors can be benign (noncancerous) or malignant (cancerous). Benign tumors tend to grow slowly and do not spread. Malignant tumors can grow quickly. They invade and destroy nearby normal tissues and spread throughout the body.
What do the terms locally invasive and metastatic mean?
Locally invasive. The tumor can invade the tissues surrounding it by sending out "fingers" of cancerous cells into the normal tissue.
Metastatic. The tumor can send cells into other tissues in the body. These may be far from the original tumor.
The original tumor is called the primary tumor. Its cells, which can break off and travel through the body, can start to form new tumors in other organs. These new tumors are called secondary tumors. The cancerous cells travel through your blood – the circulatory system – or lymphatic system to form secondary tumors. The lymphatic system is a series of small vessels that collect waste from cells. It carries it into larger vessels, and finally into lymph nodes. Lymph fluid eventually drains into

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Rank: 23
Score: 71.098
Retrieved Text: These prices reflect academic pricing. For-profit institutions should contact TopoGEN directly for a quote.
DNA methylation is an epigenetic encryption process that is a central feature of gene expression and control. DNA methylation is mediated by several DNA methyltransferases (DNMT1, 3a, 3b) that target selected genes and genomic regions. The overall process is essential for development, embryogenesis and normal tissue epistasis. Mis-regulation of DNA methylation is acutely detrimental to normal tissue function and can lead to loss of growth control in cancer ands many chronic human diseases (as well as aging). While genetic mutations in growth control gene circuits are a common antecedent step in cancer, epigenetic aberrations are very common as well, such as promoter silencing of tumor suppressing genes (p53, p21 among others). Specifically, promoter gene silencing, mediated by incorrect DNA methylation action, is an underlying etiology in these cases. Moreover, genetic alterations are fixed events (unalterable) while epigenetics, although generally stable and heritable, can be reversed using drugs (or epi-therapeutics). For example, 5’-Aza-2’-deoxycytidine (and 5-Azacytidine) are DNA hypomethylating drugs that will essentially reverse these inappropriate methylation marks at silenced tumor suppressor genes and/or activate antiviral defenses. This will in effect re-establish normal tissue epistasis and block growth and spread of malignant cells. The mechanism that controls DNA methylation in somatic cells is not well understood (2) and there is a need to: 1) identify regulatory factors in methylation; 2) identify novel pathway protein (or genes) that influence methylation; 3) characterize cell circuitry that can directly or indirectly impact epigenetic revisions; and, 4) establish the

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Rank: 24
Score: 70.84233
Retrieved Text: Purpose: The retinoblastoma gene (RB1) is a tumor suppressor gene that was first discovered in a rare ocular pediatric tumor called retinoblastoma (RB). The RB1 gene is essential for normal progression through the cell cycle and exerts part of its function through the family of transcription factors (E2F) and many other intermediaries. In the absence of normal RB1, genomic instability and chromosomal aberrations accumulate, leading to tumor initiation, progression, and ultimately metastasis. The purpose of this report was to identify the molecular pathways that are deregulated in retinoblastoma.
Methods: We compared gene expression signatures of matched normal retinal tissue and retinoblastoma (RB) tumor tissue from six individuals, using microarray analysis followed by statistical and bioinformatic analyses.
Results: We identified 1,116 genes with increased expression and 837 with decreased expression in RB tumor tissue compared to matched normal retinal tissue. Functional categories of the cognate genes with the greatest statistical support were cell cycle (309 genes), cell death (437 genes), DNA replication, recombination and repair (270 genes), cellular growth and proliferation (464 genes), and cellular assembly and organization (110 genes). The list included differentially expressed retinal cone-cell-specific markers. These data indicated the predominance of cone cells in RB and support the idea that the latter group of cells may be the cells of origin for RB.
Conclusions: The genes differentially expressed in RB as compared to normal retina belong mainly to DNA damage-response pathways, including, but not limited to, breast cancer associated genes (BRCA1, BRCA2), ataxia telangiectasia mutated gene (ATM), ataxia telangiectasia and Rad3 related gene(ATR), E2F, checkpoint kinase 1

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Rank: 25
Score: 70.40412
Retrieved Text: Isocitrate dehydrogenase (IDH) mutations are the first mutations that occur during the oncogenic process of lower-grade glioma (LGG) and confers a novel gain-of-function activity by converting α-ketoglutarate (αKG) to 2-hydroxyglutarate (2HG), promoting DNA hyper-methylation. Our analysis of LGG cases from The Cancer Genome Atlas (TCGA) database revealed that IDH-mutant (IDH-Mut) cases exhibit decreased expression of type-1 effector T cell response-related genes, which are critical for anti-glioma immunity, including: CD8A, IFNG, OAS2, GZMA, EOMES, CXCL9 and CXCL10, compared with IDH-wild type (IDH-WT) cases. On the other hand, type-2 and regulatory T cell response-related genes, such as IL5 and TGFB1, are not significantly different between IDH-Mut vs. WT cases, indicating that the observed down-regulation of type-1 response-related genes does not merely represent a possible global gene suppression. Furthermore, IDH-Mut cases exhibit increased CXCL10 promotor methylation compared with WT cases. We thus hypothesized that IDH mutation-mediated tumor intrinsic mechanisms occurring within glioma cells may inhibit anti-tumor immunity to promote tumor growth. In vitro, a normal human astrocyte (NHA) cell line transfected with IDH1-Mut cDNA expressed lower levels of CXCL10 compared to NHA cells transfected with WT IDH1. Consistently, C57Bl/6 mouse-syngeneic astrocyte and glioma cell lines transfected with IDH1-Mut expressed lower levels of CXCL10 gene and protein, compared to control cells transfected with IDH-WT, which was restored following 30 day treatment of the cells with the IDH1 inhibitor, IDH-C35. Furthermore, in vivo orthotopic IDH1-Mut gliomas at 21 days post-intracranial injection in syngeneic mice expressed lower levels of T cell chemokines CXCL9 and CXCL10 as determined by RT-PCR and ELISA and

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Rank: 26
Score: 69.88243
Retrieved Text: For the first time, CRISPR-Cas9 gene-editing technology has been employed in a whole organism model to systematically target every gene in the genome. A team of scientists at the Broad Institute and MIT's David H. Koch Institute for Integrative Cancer Research have pioneered the use of this technology to "knock out," or turn off, all genes across the genome systematically in an animal model of cancer, revealing genes involved in tumor evolution and metastasis and paving the way for similar studies in other cell types and diseases. The work appears online March 5 in Cell.
"Genome-scale guide RNA libraries are a powerful screening system, and we're excited to start applying it to study gene function in animal models," said co-senior author Feng Zhang, core member of the Broad Institute of MIT and Harvard, investigator at the McGovern Institute for Brain Research at MIT, and assistant professor in the MIT Departments of Brain and Cognitive Sciences and Biological Engineering. "This study represents a first step toward using Cas9 to identify important genes in cancer and other complex diseases in vivo."
"Tumor evolution is an extremely complex set of processes, or hallmarks, controlled by networks of genes," said co-senior author Phillip Sharp, Institute Professor at the Massachusetts Institute of Technology, board member at the Broad Institute, and member of the Koch Institute. "The in vivo application of gene-editing is a powerful platform for functional genomic discovery, offering a novel means to investigate each step in tumor evolution and identify the genes that regulate these hallmarks."
CRISPR-Cas9 gene-editing technology enables scientists to

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Rank: 27
Score: 69.834114
Retrieved Text: There are more than 30 cytokines of the TGFβ family in the human genome, including the TGFβs, the nodals, the activins, the bone morphogenetic proteins (BMPs), the myostatins, and others. These factors control many aspects of cell behavior, from early embryonic development to the regeneration and homeostasis of adult tissues.
The basic elements of the TGFβ pathway came to light more than a decade ago. Since then, the concept of how the TGFβ signal travels from the membrane to the nucleus has been enriched with additional findings, increasingly clarifying its multifunctional nature and medical relevance. However, an old mystery has endured: How does the context determine the cellular response to TGFβ? A major objective of our current research is to solve this question, which is key to understanding the biology of TGFβ and the many ways in which this pathway may malfunction.
Working in embryonic stem cells, we recently discovered that TGFβ receptors stimulate SMAD transcription factors to form a complex with the histone-binding protein TRIM33. Signal-driven SMAD-TRIM33 binds to repressive histone marks on master differentiation genes, relaxing their poised chromatin to enable companion SMAD complexes to trigger transcription. The lab is currently defining the specific mechanisms and regulatory implications of this process in both embryonic and adult stem cells.
Disseminated cancer cell in the brain. — A metastatic cell (geen) hugs a brain capillary for survival (red) in the brain parenchyma (blue nuclei). (Image, M. Valiente).
TGFβ is a powerful tumor suppressor signal. Premalignant cells that have acquired driver oncogenic mutations become sensitive to TGFβ-induced death. We are interested

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Rank: 28
Score: 69.011284
Retrieved Text: Hundreds of tumor genomes are sequenced routinely around the world every day as part of research projects or to guide therapeutic decisions. In some cases only a small portion of the genome—the part that is most likely to inform treatment options—is sequenced, while in others the coding region of the genes, or even the whole genome, is sequenced.
In both clinical and research applications, the DNA sequencing step is followed by calling the somatic variants in a tumor genome. However, the major bottleneck of tumor analysis is currently the identification of those variants that have biological or clinical relevance. This is because most of the alterations observed in a tumor, including those in well-known cancer genes, are of uncertain significance. Moreover, although new highly potent and selective anti-cancer drugs have been developed and tested in recent years, information on the tumor variants that influence their response is patchy across the literature and in several specialized resources.
To address this challenge, we have developed the Cancer Genome Interpreter, an open platform that carries out extensive annotation of the tumor variants to guide clinicians and researchers in their prioritization.
The interpretation of cancer variants is based on knowledge acquired from the analysis of cancer genomics and the accumulation of results of trials on the effectiveness of drugs on cohorts of patients or individual cases.
Decades of research on cancer genetics and the more recent mining of large tumor cohorts, sequenced by large consortia like TCGA and ICGC, have led to the identification of the genes that carry cancer-causing mutations (i.e., the drivers

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Rank: 29
Score: 68.956474
Retrieved Text: "Cells as Devices: Engineering the Genome"
"Semi-synthesis of a Neuroprotective Natural Product of Unknown Origin"
"Using Genome Engineering to Create Biomedical Swine Models"
"Transposons and Targeted Nucleases for Cancer Gene and Pathway Discovery"
This symposium will highlight emerging areas of science and technology development at the interface of biology with engineering to deliver improved healthcare. The full day symposium is comprised of three sessions that engage with scientific and thought leaders at the University of Minnesota, the Mayo Clinic and local biotech industry. The topics of the sessions are genome engineering, cancer bioengineering, and Alzheimer's disease and aging. We intend to develop a pre-eminent annual meeting for cutting-edge medical science and technology, one that embraces the full spectrum of biomedical applications and technological approaches to include molecular, genetic, and cell-based therapeutic strategies.
Dr. Largaespada is an authority on mouse genetics, gene modification, cancer genes, and disease models. His lab specializes in cancer functional genomics using in vivo transposon mutagenesis and targeted nucleases. Current projects are focused on sarcomas, brain tumors, hepatocellular carcinoma, and Neurofibromatosis Type 1 syndrome. He is currently a Full Professor in the Department of Pediatrics and the Department of Genetics, Cell Biology and Development at the University of Minnesota. He is the Associate Director for Basic Research in the Masonic Cancer Center at University of Minnesota. Dr. Largaespada currently holds the Hedberg Family/Children’s Cancer Research Fund Endowed Chair in Brain Tumor Research. Dr. Largaespada was awarded the University of Minnesota McKnight Land-Grant Professorship in 2000 and the American Cancer Society Research Professor Award in 2013. He has published

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======= Instance Index 3458 =========
Input Text: Answer the following question given this paragraph: 

Dense Connective Tissue Dense connective tissue contains more collagen fibers than does loose connective tissue. As a consequence, it displays greater resistance to stretching. There are two major categories of dense connective tissue: regular and irregular. Dense regular connective tissue fibers are parallel to each other, enhancing tensile strength and resistance to stretching in the direction of the fiber orientations. Ligaments and tendons are made of dense regular connective tissue, but in ligaments not all fibers are parallel. Dense regular elastic tissue contains elastin fibers in addition to collagen fibers, which allows the ligament to return to its original length after stretching. The ligaments in the vocal folds and between the vertebrae in the vertebral column are elastic. In dense irregular connective tissue, the direction of fibers is random. This arrangement gives the tissue greater strength in all directions and less strength in one particular direction. In some tissues, fibers crisscross and form a mesh. In other tissues, stretching in several directions is achieved by alternating layers where fibers run in the same orientation in each layer, and it is the layers themselves that are stacked at an angle. The dermis of the skin is an example of dense irregular connective tissue rich in collagen fibers. Dense irregular elastic tissues give arterial walls the strength and the ability to regain original shape after stretching (Figure 4.15).


Q: Dense connective tissue contains more collagen fibers than does loose connective tissue. as a consequence, it displays greater resistance to what?

 Choices:

- freezing

- contracting

- stretching

- stiffening

A:

Target Text: stretching

#### Retrieved Documents ####

Rank: 0
Score: 95.71498
Retrieved Text: Why are tendons made of dense regular connective tissue but the dermis contains dense irregular connective tissue?
Tendons and ligaments are made of dense regular connective tissue because they need a strong structure.
The dense regular connective tissue (CT) is different than dense irregular connective tissue. Both tissues are densely packed with collagen, a strong fibrous protein. However, they are organized differently. The dense regular CT's collagen fibers are arranged in parallel lines where the dense irregular CT's collagen fibers are packed in all different directional orientations.
The more organized the tissue, the stronger it is. The tendons and ligaments have to be strong to stand up to all of the stress we put on them, including holding much of our body weight. The reticular layer of the dermis (where you find dense irregular CT) doesn't have to be as strong. Therefore, the collagen fibers don't have to be as organized.

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Rank: 1
Score: 89.34563
Retrieved Text: Connective Tissue is the most diverse and abundant tissue type. Connective tissue makes up a variety of physical structures including, tendons, blood, cartilage, bone, adipose tissue, and lymphatic tissue.
Connective tissue has relatively few cells separated by a large amount of extracellular matrix (as opposed to epithelial tissue which exhibits high cellularity). The matrix of blood is not fibrous though and is the plasma.
All have a common embryonic origin known as mesenchyme. Mesenchyme’s are undifferentiated loose connective tissue that are capable of developing into connective tissue, such as bone and cartilage.
The suffix -BLAST roughly means immature cell or tissue and is involved in making something, in this case, the matrix. Anything with a -cyte suffix means CELL and is maintaining or involved with the final product.
Fibroblasts are cells in connective tissue that make fibrous proteins and secrete the molecules that form ground substances and collagen.
Chondroblasts secrete matrix in cartilage (to make chondrocytes).
Osteoblasts secrete matrix in bone to help create bone.
Blood cells don’t produce matrix. In blood, the ECM is plasma.
Fat cells, white blood cells and mast cells may also be present in connective tissue.
Extracellular Matrix = Ground substance that has a lot of sugar-proteins and large sugars. Extracellular matrix is composed of ground substance (ranges from gel-like to hard in texture) and protein fibers (collagen, reticular, elastic). It provides cushioning and protection such as the kidneys, which are surrounded by fat.
Collagen fibers: very strong, comparable to iron or steel but they are very tiny. These are the thickest and strongest of the 3 fibers.
Reticular fibers are found

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Retrieved Text: Connective tissues are found throughout the body. They are characterized by widely spaced cells (with one exception), and a large amount of non-living, intercellular material called the matrix. The basic function of connective tissues is to connect things together. There are eleven connective tissues. Three of these: blood, compact bone, and cancellous bone are more thoroughly discussed in the chapters on blood and skeletal tissue respectively.
The other connective tissues can be determined by the answers to two questions: 1. Are the cells in lacunae? 2. What kind of fibers are in the tissue? Before you can answer the questions, you must have a thorough understanding of lacunae and fibers!
Lacunae (sing. - lacuna) are holes within the matrix of the tissue. The cells of the tissue live inside these holes like hermits in a cave.
There are three kinds of fibers found in connective tissues. These are collagenous, elastic, and reticular. Collagenous fibers (also called dense, white, and regular) are composed of the protein collagen. They are white, long, unbranched, tightly packed, and often assume a wavy appearance. Elastic fibers are composed of the protein elastin and are elastic, that is they return to their original shape when they are stretched and released. Elastic fibers are branched. Reticular (reticulum = L. net) fibers are also branched. The branching pattern of reticular fibers is such that they form a net-like arrangement.
To identify connective tissues under the microscope ask and answer two questions: 1. Are the cells in lacunae? If so, you are looking at either osseous or cartilaginous material,

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Retrieved Text: This image shows the dense fibrous connective tissue and the nonkeratinized stratified squamous epithelium that comprise the cornea.
This is perhaps the simplest presentation of connective tissue and epithelium in the body, lacking blood vessels and complex epithelial derivatives (in contrast with, e.g., skin).
In spite of its apparent simplicity, corneal tissues are also highly specialized for transparency and precise curvature.
Corneal connective tissue, also called corneal stroma or substantia propria, consists of numerous layers of collagen fibers embedded in a glycosaminoglycan ground substance. Collagen fibers are arranged into many layers parallel to the corneal surface. The fiber orientation differs from layer to layer. Scattered within the substantia propria are the flattened fibroblasts which produce the collagen and ground substance.
Corneal epithelium consists of several (5 to 6) layers of cells. These cells are cuboidal through most of the thickness of the epithelium but become squamous (thin and flat) at the surface.
Note that epithelial tissue is classified according to the number of cell layers and the shape of surface cells, making this a stratified squamous epithelium.
Deep to the substantia propria, the single layer of cells adjacent to the aqueous humor is the so-called corneal endothelium.
Specialization for transparency. Apart from the obvious absence of blood vessels, the tissue composition of cornea appears almost identical to that of the sclera (the white of the eye). But unlike the sclera, the cornea is marvellously transparent.
The tissue elements of the cornea are specialized to minimize the scattering of light.
Although most cells and fibers are colorless, the surfaces of these elements can scatter light when

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Retrieved Text: Each day as we walk, run, sit, bend, lift or rest, our body’s complex web of fascia, ligaments and tendons work synergistically to help those movements occur. Strung in perfect balance and function throughout our structure, these connective tissues stretch, tighten and hold as needed when we engage our daily activities. Ideally movement is smooth and painless but injury, surgery and other damage can cause disruptions to this inner network inhibiting motion and causing discomfort. Such constrictions are the result of the formation of scar tissue in specific areas where wounding took place.
Any damage to connective tissues through cuts (surgery, wounds), fractures, inflammation, burns, rips or tears generates scarring as a natural repair response in the body. The scar tissue that forms consists of collagen, a strong, fibrous protein that makes up one-third of the protein in the body.
Collagen molecules are dense, fibrous strings of material that act as strong and flexible supporting structures responsible for anchoring the cells to each other in normal tissue. They also build scar tissue that glues severed connective tissue back together.
The collagen fibers in normal tissue have a random, multidirectional interwoven formation. The collagen in scar tissue has a different fibrous make-up that is more cross-linked and uni-directional than normal tissue. This scar tissue collagen alignment is more rigid and less functional than the normal collagen configuration.
An overproduction of collagen in the forming of scar tissue can overwhelm the damage site causing areas where the tissues begin to stick together rather than glide smoothly over each other. This prevents healthy

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Rank: 5
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Retrieved Text: Genacol Review – Is This Product Safe To Use?
With the need for effective healthcare services increasing every day, a lot of people are turning to supplements for their medication. In this article, we sought to explore Genacol, which is one of the many supplements available in the mart that claim to relieve pain.
What is the Company Behind Genacol?
What are the Ingredients Used in Genacol?
What are the Pros of Genacol?
What are the Cons of Genacol?
To offer you the information you require before making a decision, we have analyzed the various aspects of Genacol to help you make an informed decision before buying and using it. In particular, we have analyzed the manufacturers, the product’s pros and cons, possible side effects, and the dosage. Then, we have finally offered our verdict concerning the suitability of Genacol.
This is a joint care supplement that is developed from pure collagen through a compound formulation procedure. The product promises to help soothe joint pain and other symptoms associated with arthritis. The manufacturer claims that this supplement contains 100 percent collagen, which was recently indicated by clinical studies to have many health benefits.
The product is manufactured by Genacol Canada Corporation Inc., a company that claims to have many years of experience in the pharmaceutical industry. The manufacturer claims that it is a result of more than twenty years of intensive research.
Collagen: The supplement contains collagen as the only active ingredient. Collagen is found mostly in many multicellular living organisms. In the body, collagen is important in making the white fibers of the skin,

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Retrieved Text: Loose connective tissue, or areolar tissue, contains numerous fibroblasts that produce collagenous and elastic fibers (250x micrograph enlarged to 1,000x).
located some distance apart and are separated by a gellike ground substance that contains many collagenous and elastic fibers that fibroblasts secrete (fig. 5.18).
Loose connective tissue binds the skin to the underlying organs and fills spaces between muscles. It lies beneath most layers of epithelium, where its many blood vessels nourish nearby epithelial cells.

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Retrieved Text: The amniotic sac permits the passage of nutrients, metabolites and metabolic gases, while providing physical and immunological protection to the developing fetus. This inner most lining of the placenta consists of a thin inner amnion layer and a thick outer chorion layer.
Also known as the amniotic sac, the amnion tissue is composed of a single layer of epithelium cells, thin reticular fibers (basement membrane), a thick compact layer, and a fibroblast layer. The tissue itself contains collagen types III, IV, and V1. Amniotic tissue is derived from trophoblasts. These cells cover the developing embryo and primarily exhibit major histocompatibility complex (MHC) Class II antigens, not MHC Class I, which are present in all cadaveric tissue and are responsible for rapid rejection of the allograft.
Chorion tissue consists of a reticular layer, a basement membrane containing a layer of dense connective tissue and a trophoblast layer. In addition, the reticular and basement membrane layers contain collagen types I, III, IV, V, and VI2.

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Retrieved Text: Bone Broth — Beef, Chicken or Mushroom Chicken — Build Your Box — Save on Shipping! Certified Organic Ingredients — Non-GMO — Nourish and Repair Skin, Gut, & Joints.
Cancellous bone is a spongy type of bone inside the cortical bone. It’s not as dense as the outer cortical bone. Some bones have a lot of it, and some bones have less. A broken bone may heal faster if it has more cancellous bone inside. Bone Marrow. Your bone marrow is deep inside your bones – inside the middle of the cortical and spongy bones.
n the layer of connective tissue that varies considerably in thickness in the different areas of bone. It consists of two layers: an outer layer, which is rich in blood vessels and nerves and shows a dense arrangement of collagenous fibers, and an inner layer, the cambium, in which the fibers are loosely arranged, the cells numerous, and the blood vessels relatively sparse.
The inner osteogenic layer of bone consists of what?
The top layer is called periosteum, which is a slippery thin tissue that covers the areas where tendons (the things that connect bone to muscle) and ligaments (the things that connect bone to bone).
Compact Bone is the tough outer layer of bone while spongy bone isthe porous bone where the red and yellow marrow is. Spongy is softer bone, with holes in it. It is found inside thebone.
Periosteum, dense fibrous membrane covering the surfaces of bones, consisting of an outer fibrous layer and an inner cellular layer (cambium).The outer layer is composed mostly

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Retrieved Text: The tissue with loose arrangement of cells and the cells are scattered in an extracellular matrix are called connective tissue This non living matrix consists of a web of fibers. These fibers are embedded in a homogenous ground substance. This substance may be liquid, jelly like or solid. The nature of this – extracellular material determines the functional properties of the various.
Connective tissues mainly bind and support other tissues. In most cases, the substance of the matrix is secreted by the cells of the connective tissue. The major types of connective tissues are loose connective tissues, adipose tissue. fibrous tissues, cartilage, bone, and blood.
They Five strong, flexible fibers of collagens. These fibers are interwoven with fine, elastic, and reticular fibers. The collagens make the loose connective tissue elastic. So it makes the loose connective tissues an excellent binding tissue. .They bind epithelia to underlying tissues. They are also used as packing material to hold organ.
Adipose tissue is a type of loose connective tissue that store lipid. These cells accumulate in large numbers to.form fats.
cells osteocytes lie within lacunae. The matrix surrounds them. This matrix avily impregnated with calcium phosphate. It makes this kind of tissue hard. ey are ideally suited for the functions of suppOrt and protection.
d is a connective tissue. It has fluid called plasma. Plasma suspends initialized red and white blood cells and platelets. Blood transports various tances throughout the bodies of animals.
m sin. There are three types of muscles tissue in the vertebrate body: skeletal mu cie, cardiac muscle, muscle.
(a)keletal muscles: Skeletal muscles

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Retrieved Text: What are symptoms and signs of a connective tissue disease?
What tests to doctors use to diagnose connective tissue diseases?
Connective tissue diseases are actually a group of medical diseases. A connective tissue disease is any disease that has the connective tissues of the body as a primary target of pathology. The connective tissues are the structural portions of our body that essentially hold the cells of the body together. These tissues form a framework, or matrix, for the body. The connective tissues are composed of two major structural protein molecules, collagen and elastin. There are many different types of collagen protein that vary in amount in each of the body's tissues. Elastin has the capability of stretching and returning to its original length, like a spring or rubber band. Elastin is the major component of ligaments (tissues that attach bone to bone) and skin. In patients with connective tissue diseases, it is common for collagen and elastin to become injured by inflammation.
Diseases in which inflammation or weakness of collagen tends to occur are also referred to as collagen diseases. Collagen vascular disease is a somewhat antiquated term used to describe diseases of the connective tissues that typically include diseases that can be (but are not necessarily) associated with blood vessel abnormalities.
A common symptom of a connective tissue disease is nonspecific fatigue. Depending on which connective tissue disease is present, and how active it is, a wide variety of symptoms may occur. These include fevers, muscle and joint pain and stiffness, weakness, and many other symptoms. Please refer

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Retrieved Text: There are two primary influences in skin aging - chronological aging and extrinsic aging. Chronological aging is the natural progression of aging while extrinsic skin aging is caused by external factors, mainly chronic sun exposure, pollution, smoking, poor diet and lifestyle.
The most visible effect of skin aging occurs when there is a decline in the skin’s connective tissue and water content. Fine lines and wrinkles are created due to the overall weakening and loss of skin collagen structure, resulting in a decline in skin health.
WHAT IS COLLAGEN? WHAT DOES IT DO FOR THE SKIN?
There are approximately 27 types of collagen, classified by their size, function and amino acid composition. Type I is the most important collagen for skin tissue.
Collagen is an abundant protein and main building block in the body. A vital component of connective tissue in our joints, tendons and ligaments, collagen is also the primary protein that keeps skin smooth, firm and helps to lock in skin moisture.
The skin is comprised of three distinctive layers, the epidermis, dermis and hypodermis. The outer most layer (the epidermis,) provides protection against foreign substances and a barrier from the external environment. The dermis is directly below and gives skin its strength and support. It is the dermis that contains nerves, blood vessels and fibroblasts (a cell in connective tissue that produces collagen and elastin fibers,)that receive essential nutrients to produce new skin cells and maintain the structural foundation of the skin. Collagen is the most abundant protein within this structural framework that gives skin its strength. Elastin

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Retrieved Text: Smooth Musculature - want to learn more about it?
Smooth muscle is a type of tissue found in the walls of hollow organs, such as the intestines, uterus and stomach. You can also find smooth muscle in the walls of passageways, including arteries and veins of de cardiovascular system. This type of involuntary non-striated muscle is also found in the tracts of the urinary, respiratory and reproductive systems. In addition to that, you can find smooth muscle in the eyes, where it acts to change the size of the iris and the shape of the lens. The skin is also contains smooth muscle which allows hair to raise in response to cold temporatures or fear.
The smooth muscle cell is 3-10 µm thick and 20-200 µm long. The cytoplasm is homogeneously eosinophilic and consists mainly of myofilaments. The nucleus is located in the center and takes a cigar-like shape during contraction. The cell membrane forms small pouch-like invaginations into the cytoplasm (caveolae) which are functionally equivalent to the T-tubules of the skeletal musculature. The smooth muscle cells are anchored to the surrounding connective tissue by a basal lamina.
The smooth muscle fibers group in branching bundles. As opposed to skeletal muscle fibers these bundles do not run strictly parallel and ordered but consist in a complex system. Thus the cells can contract much stronger than striated musculature. The actin filaments are stretched between dense bodies in the cytoplasm and attachment plaques at the cell membrane. The myosin filaments lie between the actin filaments. Furthermore intermediate filaments such as desmin

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Retrieved Text: Collagen and elastin are two types of proteins that form the fibrous component of the connective tissue. Collagen is wide spread in the body than elastin. The main difference between collagen and elastin is that collagen gives strength and flexibility whereas elastin returns the stretched structures into the original shape. Collagen is a white color protein whereas elastin is a yellow color protein. Collagen is the third abundant protein in a mammal’s body. It is found in connective tissues as well as in skin, tendon, ligaments, and bones. Elastin is the major protein found in elastic connective tissues. It is mainly found in blood vessels and skin.
Collagen is the main fibrous protein in the body. It is mainly found in the extracellular matrix of connective tissues. Collagen makes up the 25% of the total protein mass of a mammal. Collagen mainly comprises of amino acids, glycine and proline. It also consists of hydroxyproline and arginine. The collagen is stained in pink in H&E staining. Fibroblasts in the connective tissue secrete collagen as procollagen. Vitamin A, vitamin C, and copper are required for the production of collagen in fibroblasts. The cleavage of the end amino acids in procollagen forms the collagen, which ultimately aggregates into fibers. A collagen molecule is composed of three protein chains wrapped around each other, forming a helix. A large collagen aggregate is called a tropocollagen, which is formed by the aggregation of collagen fibrils. Collagen fibrils are cross-linked together in order to achieve a large tensile strength. Around 15 types of collagen

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Retrieved Text: The extracellular matrix is a meshwork of proteins and carbohydrates that binds cells together or divides one tissue from another. The extracellular matrix is the product principally of connective tissue , one of the four fundamental tissue types, but may also be produced by other cell types, including those in epithelial tissues. In the connective tissue, matrix is secreted by connective tissue cells into the space surrounding them, where it serves to bind cells together. The extracellular matrix forms the basal lamina, a complex sheet of extracellular matrix molecules that separates different tissue types, such as binding the epithelial tissue of the outer layer of skin to the underlying dermis, which is connective tissue. Cartilage is a connective tissue type that is principally composed of matrix, with relatively few cells.
Collagens are the principal proteins of the extracellular matrix. They are structural proteins that provide tissues with strength and flexibility, and serve other essential roles as well. They are the most abundant proteins found in many vertebrates. There are at least nineteen collagen family members whose subunits, termed α chains, are encoded by at least twenty-five genes . The primary protein sequence of all collagen subunits contains repeating sequences of three amino acids , the first being glycine with the second and third being any amino acid residue (sometimes referred to as a GLY–X–Y motif).
Most, if not all, collagens assemble as trimers , with three subunits coming together to form a tightly coiled helix that confers rigidity on each collagen molecule. Assembly of the collagen trimer occurs

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Retrieved Text: Warning: This video contains footage of dissections of human bodies that may be disturbing for sensitive viewers.
The 2018 DW Documentary, “The Mysterious World Beneath the Skin,” delves into the workings and functions of your fascia, the fibrous connective tissue found throughout your body. Remarkably, this thin layer of tissue accounts for about 20 percent of your body mass.
As explained by Dr. Jerry Tennant in his book, “Healing Is Voltage: The Handbook,” your muscles are stacked one on top of the other in a specific order (much like batteries in a flashlight) to form a power pack. Each organ has its own battery pack, which is a stack of muscle batteries.
These muscle batteries are in turn surrounded by fascia, which acts as a semiconductor — an arranged metabolic molecule designed to move electrons at the speed of light, but only in one direction.
Together, the muscle stack and the surrounding fascia serve as the wiring system for your body, carrying the voltage from the muscle battery inside, out, through the fascia and to the appropriate organ. In addition to moving electricity, fascia also acts as a hydraulic pump, and is responsible for moving fluid around your body.
As noted by Dr. Dana Cohen, a doctor of internal medicine and author of “Quench: Beat Fatigue, Drop Weight, and Heal Your Body Through the New Science of Optimum Hydration,” a book about optimizing hydration, your fascia is actually a movement system for water in your body. To activate this system — and optimize cellular hydration — you have to engage in

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Retrieved Text: It is harder to identify nerve fibers and connective tissue in this cross section of a dorsal root ganglion because both stain pink/red.
Compare this slide with MH 051 Dorsal Root Ganglion (Azan).
Ganglion Cells - large, nerve cell bodies with large nuclei and prominent nucleoli. Their cytoplasm contains abundant Nissl substance.
Lipofuscin - yellow-brown pigment granules in some nerve cell bodies.
Nerve Fibers - unmyelinated and myelinated axons of different diameters seen in cross-section.
Axon - pink material at the center of each nerve fiber..
Schwann Cells - glial cells that wrap axons in the peripheral nervous system. Their large, round nuclei are adjacent to some axons.
Myelin Sheath - pink/red material surrounding myelinated axons. Often has a fluted appearance.
Endoneurium - connective tissue (dark blue) surrounding each nerve fiber.
Capsule - dense irregular connective tissue (pink/red) that is continuous with the epineurium of the nerve.

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Retrieved Text: Cosmetically seen this circumstance is for many women the beauty problem no. 1: After all, eight out of ten women more or less affected. Age and weight do not always play a significant role.
Man is born with a genetically fixed number of fat cells. These fat cells can store unused, partly superfluous fats and thus be extended to the 3 to 10 times its original size. The female body is programmed to the so-called menopause on pregnancy and the creation of reserves for bad times. During evolution, a skin structure with a loose federation of parallel collagen and elastic fibers has, controlled by hormones, formed. This enables optimum matching the required elongation of the connective tissue during pregnancy. In men, the connective tissue is like a grid connected and thus significantly less stretchy.
Physiologically, cellulite is an uneven distribution of enlarged fat cells in the connective tissue, especially on bottom and thighs, the natural reservoirs of the body. At the same time, the enlarged fat cells connect lump-like, tissue fluid accumulates in itself. This complicates the natural disposal of the connective tissue metabolism of residual products and toxins through the lymphatic vessels and blood vessels. Manifested externally is Cellulite, also called orange peel, with dents and waves. There are many different cellulite structures. In the mild form it only shows up when the fabric is pushed with hands together. Stronger cellulite is already visible when tensing the muscles.
As we know now is to bring the positive capacity of the female body during pregnancy the fetus safely through

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Retrieved Text: 8.4: What else does a piece of meat contain?
is responsible to hold all the muscles together.
Actually, it can able to organize and coordinate the actions.
For those muscle, which require more force, or more energy.
muscle, so that it able to do much harder work.
So, that's why the connective tissue, normally, it is tough, and very strong.
on the land, basically, they require the muscle function quite often.
the connective tissue is relatively tougher.
So you may wonder what's inside the connective tissue.
In fact it contains three type of tissues.
try to heat it for certain temperature, the collagen is become softer.
The main reason is for the structure of collagen.
In fact, it contains three strands of amino acids.
which has much softer textures as compared to collagen.
once it's born basically the amount of collagen is more or less constant.
contains certain amounts of collagen, you still can able to change to gelatin.
those collagen, as times goes by, it becomes coalescing to each other.
a really important role in the meat textures.
heat it to about 60 degrees the three strands of amino acids start to unwind.
hit it at 60 degree for a longer period of time, it becomes so in structure.
the fish, they hardly move, so that they contain much less collagen.
feeling of dried meat, normally, more or less in the middle of the fish muscle.
But, however, for the tail, it actually contain more connective tissues.
At a high temperature, it can able to connect to gelatin.
It gives you a much more juicy texture afterwards.
The next I'm going to tell you is the fat.
Fat in fact we

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Retrieved Text: (corium, cutis, true skin), the connective-tissue part of the skin in vertebrates and man, located beneath the epidermis.
The dermis is normally more or less loosely connected to the subjacent organs by loose subcutaneous connective tissue, which is often rich in fatty deposits. The dermis consists of two layers. The surface (papillary, spongy, subepithelial) layer functions mainly to nourish the epidermis and its derivatives (glands, feathers, hairs); it is rich in blood vessels, has a relatively loose structure, and, in some animals, forms papillae that project into the epidermis. The layer beneath it (reticular, compact) constitutes most of the dermis. It consists of solid connective tissue and has mainly a supportive function.
The deep layer of the skin, a dense connective tissue richly supplied with blood vessels, nerves, and sensory organs. Also known as corium; cutis.
Histopathology shows the presence of mature adipocytes in the dermis that mostly lacks any connection with the subcutaneous fat.
En la dermis se observan vasos sanguineos muy enrollados y dilatados.
Thinning of the dermis sees a reduction in blood vessels, nerve endings and collagen.
In the present study five different protocols were used to obtain the acellular dermis from the deepithelialized skin.
To stiffen the dermis, the repetitive compression of 15% strain at the frequency of 1 Hz for 90 s was applied.
Generally, the skin of mammals can be divided into three components: epidermis, dermis, and hypodermis.
Prof Maitz said initial testing of the artificial dermis in mice demonstrated it does not scar and contract when it is transplanted.
The subcutaneous layer, or subcutis, is a layer of fatty

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Retrieved Text: Brisket can be cooked many different ways. Basting the meat is essential during cooking. Brisket of beef on the bone needs to be slowly cooked at a low temperature due to the collegen fibers that make up the significant connective tissue in the cut. The slow cooking helps tenderize the brisket, as the collagen gelatinizes, resulting in more tender beef. The fat cap can be left attached to the brisket, which helps to keep the meat from drying during the prolonged cooking necessary to break down the connective tissue in the meat. Water is necessary for the conversion of collagen to gelatin.

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Retrieved Text: Grape seed extract (GSE) contains proantho-cyanidins. These compounds have potent anti-oxidant properties, and have a high affinity for collagen fibers in the body. They appear to work both by increasing the production of new collagen as well as inhibiting its breakdown. They strengthen the collagen by their presence, and protect it from free-radical,and inflammatory,damage. GSE inhibits the activity of the enzymes that break down collagen (hyaluronidase, elastase, and collagenase), and thereby decreases the breakdown of connective tissue in general and collagen in particular.

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Retrieved Text: As you may know, a supply of cellular nutrients in MS is very important. That's why we have two important ingredients in one product for you to get to know!
Dr. Rath LyCin™ - with the essential amino acid lysine and vitamin C. It supports the connective tissue, musculoskeletal and calliper system of the body. Connective tissue surrounds the nerves, vessels and organs and connects all components with each other.
At the same time, connective tissue also has protective functions for the body, so that the buildup and maintenance of collagen fibers and connective tissue are important metabolic processes overall. Lysine is an essential but non-self-producible amino acid and must be supplied through the diet.
Get to know our product Dr. Rath LyCin™ and convince yourself of its excellent properties.
Your introductory price of 29.50 € is valid until 15.06.2018. This offer cannot be used with member discounts or any other discounts.

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Retrieved Text: proto-col collagen pro sports tablets are a special blend of type I and type III collagen.
Contains 1000mg of hydrolysed collagen.
Each collagen tablet contains 1000mg/1 gram of pure collagen hydrolysate. Our collagen is type I and III with an optimised type II grade. Our jar contains 150 tablets with a recommended serving of 3 to 5 tablets per night.
Collagen is the main structural protein of the various connective tissues in all humans and animals. Collagen is also the main component of connective tissue; it is the most abundant protein in mammals, making up from 25-35% of the whole-body protein content, which in turn is approximately 30% of total body mass. Depending on your goal i.e. beauty enhancement with the reduction of lines and wrinkles, or connective tissue repair, collagen hydrolysate can play a key role.
There are numerous types of collagen hydrolysate in the marketplace; collagen hydrolysate can be derived from fish (marine), chicken sternum, porcine and bovine. However to date there is no clinical evidence that any collagen other than from a bovine source actually works. This research has been authenticated by the CRI (Collagen Research Institute) which is based in Kiel, Germany and headed by the world’s leading authority on Collagen Hydrolysate research Dr Steffen Oesser.
You also have to take into account the production method and the grade of collagen. This plays a huge factor in whether you will see results for skin or for connective tissue. For tissue repair which incorporates ligaments, tendons, muscles and cartilage you require far larger amounts of collagen than what

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Retrieved Text: It is the unique combination of amino acids in concentrated levels. The body's natural ability to repair supporting connective tissue (Bone, tendons, ligaments, cartilage, skin, hair and nails) diminishes in one's mid-twenties. Collagen contains amino acid such as glycine, lysine and proline, which are important amino acids and can be used by the body to build connective tissue structures to support the functions of the cells. Hot or cold liquid soluble for use in cold beverages or recipes. Collagen Hydrolysate will not congeal because it has been hydrolyzed for quick assimilation into the body. Collagen is important to nitrogen balance, and may prevent age related cartilage damage and collagen loss.
Contains protein of low molecular weight, providing quick absorption in digestive tract.
Contains amino acids such as glycine, lysine and prolineto help build and repair connective tissue.
Hydrolyzed collagen is the same collagen naturally found in bones, skin and cartilage.
Collagen is important to nitrogen balance and may prevent cartilage damage and collagen loss.
Cold liquids: Add two tablespoons to one or two ounces of room temperature liquid and stir. Add cold liquid and mix completely.
Room temperature liquids: Pour two tablespoons into a glass of your favorite juice or drink and mix well.
Hot liquids: Add two tablespoons to container, Then add HOT liquid, stir until dissolved.

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Retrieved Text: Tendinitis is one of the most common diagnoses for soft tissue pain resulting from repetitive motion. As repetitive motion disorders have dramatically increased, so has the incidence of tendinitis. However, recent investigations into the cellular nature of tendon pathologies have brought forth interesting discoveries that may alter the way tendinitis is treated. In this month's column, let's take a look at some of these fascinating discoveries.
The first stop along the way is to take a closer look at the anatomical and biomechanical characteristics of tendons. Tendons are connective tissue structures that are primarily composed of collagen and elastin fibers. Collagen fibers primarily give the tendon its strength, and elastin fibers give it a small amount of flexibility.
Since the tendon fibers are primarily designed to transmit a strong tensile (pulling) load from the muscle directly to the bone, the tendon is not designed to be very flexible. If it were very flexible, much of the muscle's contraction force would be absorbed by the tendon and not transmitted to the bone. It would be like trying to pull a heavy object across the floor with a bungee cord instead of a rope.
The tendon gets its strength not only from the quantity of collagen fibers it contains, but also from the arrangement of the fibers. In tendons, the collagen fibers are arranged mostly in a parallel direction, in line with the direction of the muscle fibers. This arrangement will give the tendon the greatest amount of strength in the direction that the muscle fibers are pulling. Ligaments, on the

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Retrieved Text: You may already know that 70% of your body weight is water, which is essential for your connective tissue hydration and the ability to keep your body mobile and healthy. But did you also know that proteins are also a big part of your body composition? They have an important role to play by providing structure and function to your heart, lungs, kidneys, brain, and of course skin, bones, and the rest of your connective tissue.
With a presence of approximately 30%, collagen is the most frequently found protein in the body and a very significant component of your connective tissue, playing a main role as a building block of your bones, cartilage, tendons, ligaments, fascia, and everything surrounding it. Collagen is stabilizing and it gives elasticity to your connective tissue!
Collagen architecture is the key to fascia functionality, which is an important part of your connective tissue health. Collagen density and architectural patterns are deciding factors in tissue stability and elasticity. Collagen is an active force transmitter and has amazing tensile strength—scientists like to compare it to a steel cable. These qualities can make your movement more energy conservative rather than energy consuming and improve your overall performance!
Type I Collagen: Accounts for about 90% of the body’s total collagen content, mainly in the connective tissue of the skin, bones and tendons.
Type III Collagen: Found in skin and muscles.
Types I & III are the types of collagen present in Resync Collagen Blend.
What are collagen peptides and why are they beneficial?
Collagen peptides are smaller pieces of collagen that are

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Retrieved Text: What is Radiofrequency Skin tightning?
This technology painlessly delivers focused and optimal radio-frequency (RF) energy to the skin surface and to subcutaneous fat layers. Controlled energy is delivered via three or more electrodes and limited to the treatment area. This focused delivery results in immediate visible results. For improved results it is recommended to undergo a series of treatments.
Different modes allows practitioners to choose between body and/or facial treatments. Targeted facial treatment regenerates collagen fibers in the dermis layer. Targeted body treatments shrink fat cells in the hypodermis layer and accelerate collagen regeneration.
How does RF technology work?
As our skin matures and is continuously subjected to environmental effects, its connective tissue begins to break down, causing wrinkles and other signs of ageing develop.
The Tripolar RF energy penetrates the skin layers to selectively heat the skin tissue and the extra-cellular matrix (ECM) where the Collagen fibers are embedded. The local heating causes an immediate contraction of the collagen fibers, and at the same time increases the metabolism of the Fibroblasts thereby accelerating the production of new Collagen and Elastin fibers.
The contraction of Collagen fibers and the regeneration of the Collagen and Elastin deposits, tighten the skin layers creating smoother, healthier and younger looking skin.

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Retrieved Text: 1. A hard connective tissue consisting of cells embedded in a matrix of mineralized ground substance and collagen fibers. The fibers are impregnated with inorganic components, including crystals of calcium phosphate, such that using X-ray defraction, they are seen to be organized in a hydroxyapatite pattern (calcium phosphate is 85% by weight) as well as calcium carbonate (10%), and magnesium; by weight, bone is composed of 65–75% inorganic and 25–35% organic material; a portion of osseous tissue of definite shape and size, forming a part of the animal skeleton; in humans there are approximately 200 distinct bones in the skeleton, not including the auditory ossicles of the tympanic cavity or the sesamoid bones other than the two patellae. A bone is enveloped by a fibrous membrane, periosteum, that covers the bone's entire surface except for the articular cartilage. Beneath the periosteum is a dense layer, compact bone, and beneath that a cancellous layer, spongy bone. The core of a long bone is filled with marrow.

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Retrieved Text: Slide #DMS 033 [Thick Skin]. Glabrous "thick skin" is found in limited areas of the bodu, such as the soled of the feet and palms of the hands.
Identify the following epidermal strata: basale (germinativum), spinosum, granulosum. lucidum (often difficult to discern), and corneum. In which one of these layers would you expect to find mitotic figures? Study the spinosum at high mag. Note the so-called "intercellular bridges" (spines) between the keratinocytes from which this layer derives its name. Recall that this appearance reflects a shrinkage artifact as the cells pull away from each other during dehydration, and remain connected only by their desmosomal junctions. Note the keratohyaline granules in the stratum granulosum. What is their composition/function? At what strata do the keratinocytes become so heavily keratinized that they die and become cornified plates (squames)? Identify the papillary and reticular layers of the dermis. Find dermal papillae. What important sensory organs are found within the papillae? Now define the hypodermis. Note the abundance of blood vessels, nerves, and glands. What specific kind of glands? Find their secretory units and ducts. What type of epithelium lines the ducts. Try to follow the ducts through the epidermis proper to their openings at the surface of the stratum corneum. Look at the skin of your finger tip using an inverted ocular as a hand lens. Where are the openings of the ducts located?
A distinct basement membrane separates the epidermis from the underlying connective tissue dermis. The interface between these two strata, the dermoepidermal junction, varies over the body from relatively

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Input Text: Answer the following question given this paragraph: 

Sexual reproduction involves haploid gametes and produces a diploid zygote through fertilization.


Q: Sexual reproduction involves haploid gametes and produces a diploid zygote through what process?

 Choices:

- infection

- vivisection

- fertilization

- sedimentation

A:

Target Text: fertilization

#### Retrieved Documents ####

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Retrieved Text: Young to old. A life cycle?
Not in the biological sense. Life cycles describe the amount of DNA present at a specific stage or time in the life of an organism. Is there a haploid or diploid amount of DNA? That is the key question.
Sexual reproduction occurs in a cycle. Diploid parents produce haploid gametes that unite and develop into diploid adults, which repeat the cycle. This series of life stages and events that a sexually reproducing organism goes through is called its life cycle. Sexually reproducing organisms can have different types of life cycles. Three are represented in Figure below and described following sections.
Life cycles can vary in sexually reproducing organisms. Three types of sexual life cycles are shown here. Do you see how they differ? The letter n indicates haploid stages of the life cycles, and 2n indicates diploid stages.
The haploid life cycle is the simplest life cycle. It is found in many single-celled eukaryotic organisms. Organisms with a haploid life cycle spend the majority of their lives as haploid gametes. When the haploid gametes fuse, they form a diploid zygote. It quickly undergoes meiosis to produce more haploid gametes that repeat the life cycle.
Plants, algae, and some protists have a life cycle that alternates between diploid and haploid phases, known as alternation of generations. In plants, the life cycle alternates between the diploid sporophyte and haploid gametophyte. Spore forming cells in the diploid sporophyte undergo meiosis to produce spores, a haploid reproductive cell. Spores can develop into an adult without fusing with another cell.

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Retrieved Text: Download "Rhizarians. Forams. Radiolarians. Cercozoans"
14 Figure 29.3 Exploring Derived Traits of Plants Charophyte algae lack the key traits of plants described in this figure: alternation of generations; multicellular, dependent embryos; walled spores produced in sporangia; multicellular gametangia; and apical meristems. This suggests that these traits were absent in the ancestor common to plants and charophytes but instead evolved as derived traits of plants. Not every plant exhibits all of these traits; certain lineages of plants have lost some traits over time. Alternation of Generations The life cycles of all plants alternate between two generations of distinct multicellular organisms: gametophytes and sporophytes. As shown in the diagram below (using a fern as an example), each generation gives rise to the other, a process that is called alternation of generations. This type of reproductive cycle evolved in various groups of algae but does not occur in the charophytes, the algae most closely related to plants. Take care not to confuse the alternation of generations in plants with the haploid and diploid stages in the life cycles of other sexually reproducing organisms (see Figure 13.6). Alternation of generations is distinguished by the fact that the life cycle Mitosis n Alternation of generations: five generalized steps 5 The spores develop into multicellular haploid gametophytes. n MEIOSIS 1 The gametophyte produces haploid gametes by mitosis. Gametophyte (n) Spore includes both multicellular haploid organisms and multicellular diploid organisms. The multicellular haploid gametophyte ( gamete-producing plant ) is named for its production by mitosis of haploid gametes eggs and sperm that fuse during

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Retrieved Text: A cell or nucleus that may participate in sexual fusion to form a *zygote. It is normally haploid and thus on fusion of two gametes a diploid zygote is formed. In virtually all plants (exceptions are those with a *diplontic life cycle ) meiosis is separated from *gametogenesis by the development of a somatic gametophyte generation (see alternation of generations ). In the primitive algae and fungi the gametes are often naked and *isogamous. In more advanced forms there is a trend through *anisogamy to *oogamy and specialization of the gametes, so that they become better protected and less dependent on water for survival and dispersal. See also sexual reproduction.

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Retrieved Text: Individual organisms come and go, but, to a certain extent, organisms transcend time through producing offspring. Reproduction in animals occurs in two primary ways: through sexual reproduction and through asexual reproduction.
Now let's take a look at sexual reproduction.
In sexual reproduction, two individuals produce offspring that have genetic characteristics from both parents. Sexual reproduction introduces new gene combinations in a population.
In animals, sexual reproduction encompasses the fusion of two distinct gametes to form a zygote. Gametes are produced by a type of cell division called meiosis.
The gametes are haploid (containing only one set of chromosomes) while the zygote is diploid (containing two sets of chromosomes).
In most cases, the male gamete, called the spermatozoan, is relatively motile and usually has a flagellum. On the other hand, the female gamete, called the ovum, is nonmotile and relatively large in comparison to the male gamete.
There are two mechanisms by which fertilization can take place.
The first is external (the eggs are fertilized outside of the body); the second is internal (the eggs are fertilized within the female reproductive tract).
For example, many animals have estrous cycles that occur during certain parts of the year so that offspring can typically be born under favorable conditions. Humans however, do not undergo estrous cycles but menstrual cycles.

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Retrieved Text: Asexually reproducing organism can cope with a changing environment only through relatively rare spontaneous mutations that prove to be beneficial.
This process does not allow any variation in their population, though it is opposite in the case of sexual reproduction, which accepts variations in their population.
These offsprings are parents again give rise to new one.
No fertilization occurs during asexual reproduction. And due to which sexual reproduction is considered as the most fundamental aspect of evolution. These offspring are usually referred to as clones . Time is taken to complete Multiplication is very rapid and in lesser time. Starfish Regenerating its Legs Agamogenesis Any form of reproduction which does not involve male gametes is known as agamogenesis.
What is asexual reproduction? Types of asexual reproduction There are several different types of asexual reproduction but the most common ones include binary fission, budding, fragmentation and spores.
The number of offspring may vary from two to many and are genetically similar in asexual reproduction whereas the number of offspring produced are less in number comparatively which are genetically different from their parents.
There are specialized organs present in male and female gametes for sexual reproduction in plant and animals. If it continues to grow normally it can eventually become a baby. This combination of gametes is named treatment.
Both of these forms of reproduction occur in plants, fungi and animals however the specific form of reproduction will depend on the species . Puffballs Emitting Spores Sexual Reproduction of Plants Bryophytes like liverworts, mosses, and hornworts consist of motile sperms with flagella.
Fertilization takes place in

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Retrieved Text: Plants are multicellular organisms in the kingdom Plantae that use photosynthesis to make their own food. There are over 300,000 species of plants; common examples of plants include grasses, trees, and shrubs. Plants have an important role in the world’s ecosystems. They produce most of the world’s oxygen, and are important in the food chain, as many organisms eat plants or eat organisms which eat plants. The study of plants is called botany.
Plants are autotrophs; they produce their own food. They do so via photosynthesis, which is the process of making nutrients such as sugars from light energy and carbon dioxide. Photosynthesis occurs in cell organelles called chloroplasts, which contain chlorophyll and carotenoids, molecules that absorb light energy and change it into a usable form. Heterotrophs, on the other hand, are organisms that cannot make their own food and must eat other organisms to survive. Many heterotrophs eat plants. Other heterotrophs eat animals that have eaten plants. Plants are primary producers in many ecosystems, giving them a vital role in the survival of many other organisms. In addition, oxygen is a byproduct of photosynthesis, and many organisms depend on oxygen to survive. We couldn’t live without plants.
Plants are multicellular organisms with eukaryotic cells. A eukaryotic cell is a relatively large cell with a true nucleus and other organelles that perform specific functions. Plants, protists, fungi, and animals all have eukaryotic cells. Plant cells are distinguished by their cell walls containing cellulose, chloroplasts that perform photosynthesis, and a large central vacuole that holds water and keeps the

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Retrieved Text: Distinguish, differentiate, compare and explain what is the main difference between Gametogenesis from Embryogenesis. Comparison and Differences.
1. Gametogenesis is the formation of male and female gametes. Embryogenesis is the formation of an embryo from the zygote.
2. In Gametogenesis, gametes are the haploid cells. In Embryogenesis, an embryo is a diploid cell.
3. Both mitotic & meiotic cell division take place in Gametogenesis. Only mitotic division occur in Embryogenesis.

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Retrieved Text: die „Reduktionsteilung“ beginnt im Diplonten mit einer eigenartigen Zelle [...], deren Nachkommen, die „Haploten“ [...] auf die ursprüngliche Chromosomenzahl herabgesetzt sind, und wiederum ein einfaches Lebewesen, den „Haplonten“ [...] durch neue Zellenteilungen erzeugen.
From this organism [the haplont] arise the gametes by ordinary mitosis; and by their union is produced the zygote from which arises a diploid, asexual spore-producing diplont (in plants the sporophyte), thus completing the life-cycle.
1: The diploid stage of a life cycle; diplophase, 2: An organism having a life cycle in which the direct products of meiosis act as gametes; only the gametes of diplonts are haploid; cf. haplont.

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Retrieved Text: (Solved) The union of gametes produces a zygote.
The union of gametes produces a zygote.
Solved If gametes were diploid like somatic cells, how many chromosomes would the zygote contain?

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Retrieved Text: 1. the process of reproduction.
2. a class composed of all individuals removed by the same number of successive ancestors from a common predecessor, or occupying positions on the same level in a genealogical (pedigree) chart.
alternate generation reproduction by alternate asexual and sexual means in an animal or plant species.
asexual generation (direct generation) production of a new organism not originating from union of gametes.
first filial generation the first-generation offspring of two parents; symbol F1.
parental generation the generation with which a particular genetic study is begun; symbol P1.
second filial generation all of the offspring produced by two individuals of the first filial generation; symbol F2.
sexual generation production of a new organism from the cell formed by the union of a male gamete (spermatozoon) and a female gamete (oocyte).
spontaneous generation the discredited concept of continuous generation of living organisms from nonliving matter.
reproduction by fission, gemmation, or in any other way without union of the male and female cell, or conjugation.
Reproduction by fission, gemmation, or in any other way without union of the male and female cells, or conjugation.
Synonym(s): heterogenesis (2) , nonsexual generation.
2. a class composed of all individuals removed by the same number of successive ancestors from a common predecessor, or occupying positions on the same level in a genealogical (pedigree) chart. Said also of antibiotics or other chemicals derived from parent compounds.
reproduction by alternate asexual and sexual means in an animal or plant species.
production of a new organism not originating from union of gametes. Called also direct generation.
the first generation offspring of two parents; symbol F1.
all of

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Retrieved Text: Mitosis is the process of cell division that enables organisms to maintain cell populations and grow. All chromosomes duplicate themselves prior to cell division, followed by partitioning of these exact copies into daughter cells. In the image to the right, two sets of chromosomes are going through mitosis.
In contrast, meiosis is a two-part cell division process which results in reproductive cells (eggs and sperm) with one-half the number of chromosomes of the parent cell.
In males, the process results in four equal gametes with one chromosome each (sperm cells—not shown). In females, each ovum is produced by two chromosome divisions, called the first and second meitic divisions, and the parent cell's cytoplasm and organelles end up in one gamete.
When a haploid sperm cell fertilizes a haploid ovum, a diploid zygote is formed, with one set of chromosomes donated from each parent.

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Retrieved Text: This biphasic life cycle that plants demonstrate is referred to as an?
The life cycle of a plant from?
The leafy green gametophyte is the haploid generation that produces sperm and eggs. The sperm must swim through a film of water to the egg. The zygote develops into a stalked, diploid sporophyte that emerges from the gametophyte plant. The sporophyte is topped by a brown capsule in which haploid spores are produced by meiosis. These are dispersed and germinate, producing another green gametophyte generation.
What is the function and structure of the flower?
Flowers are the part of the sporophyte generation in flowering plants that is dedicated to sexual reproduction.
Insect and vertebrate pollination is ____ efficient than wind pollination.
that put more efforts into mechanisms to attract the animals (i.e. nectar, odoriferous compounds, appearance and etc.) ensured the success of those flowering plant lineages.
Stamens and carpels are composed of two to three distinctly different parts.
1.) To recap pollination is when a pollen grain lands on the stigma of a flower's carpel.
2.) The pollen generates a tube to transfer the sperm from the male gametophyte to the female gametophyte.
3.) In flowering plants we see a double fertilization from the fusion of the sperm to specific cells of female gametophyte.
4.) This double fertilization gives rise to a zygote and endosperm.
5.) When the female gametophyte develops in the manner previously illustrated (polygonum type), which is the most common, the double fertilization gives rise to a (2n) zygote and a (3n) endosperm.
How do seeds germinate and grow?
Seeds need moisture and warmth to germinate. If conditions

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Retrieved Text: Spirogyra is one of the commonest and large genus with about 300 species growing as free-floating masses in stagnant or slowly moving waters (streams). Some species, e. g., Spirogyra adnata are attached to the substratum through a basal rhizoidal cell. The masses of plants are slimy to touch because the filaments are surrounded by pectic sheaths which when come in contact water forms mucilage, therefore it is known as water-silk or pond-scum. The spirogyra grows abundantly in spring.
Spirogyra is unbranched with cylindrical cells connected end to end in long green Filaments. The individual cell is cylindrical, much longer than broad. In free-floating species, there is no distinction between the basal and distal ends, whereas in attached forms the lowermost cell develops a rhizoidal outgrowth called holdfast which helps in attachment.
Each has a well-developed cell wall. The cell wall has two layers the outer wall is composed of cellulose while the inner wall is of pectin.
The cytoplasm forms a thin lining between the cell wall and the large vacuole. Electron microscope studies show that mitochondria, endoplasmic reticulum, dictyosomes and other cytoplasmic inclusions are also present in the cell. The chromosomes vary from species to species from 5-24.
Each cell has a prominent nucleus in the center, suspended by the thin strands of cytoplasm from the inner part of the cell wall.
Chloroplasts are embedded in the peripheral Cytoplasm and their numbers are variable (as few as one). The chloroplasts are ribbon shaped and spirally resulting in the prominent and characteristic green spiral on each filament chloroplast contains several pyrenoids,

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Retrieved Text: Algaes are difficult to define. Some classify the group as all eukaryotic photosynthesizing microorganisms. This definition includes the Euglenoid and Dinoflagellates groups, both of which are known to be more closely related to other groups of non-photosynthesizing protozoa than to other algae. For this reason, those two groups are sometimes classified as protozoa rather than algae. In this discussion, we will group euglenoids and dinoflagellates with the algae so that we may compare their photosynthetic characteristics. Keep in mind that this inclusion does not imply close relation to other algae.
Another difficulty in classifying algae is determining whether they are protists, plants, or whether they merit their own kingdom. Different classification systems answer this question in different ways, with some even splitting the group between the kingdoms Protista and Plantae. Here we have grouped algae with protozoa and slime molds in Protista because mthe majority of algae are unicellular, and even the multicellular algae are structurally simple compared to true plants.
Within the classification of algae, individual species are divided into five groups, based on characteristics such as type of chlorophyll molecule used in photosynthesis and type of reproductive cycle. The structure of the chloroplast is also used, for a very important reason. According to the endosymbiotic theory of chloroplast evolution, proposed by Lynn Margulis of the University of Massachusetts, Amherst, chloroplasts may have evolved when small photosynthesizing cells were engulfed, but not digested, by larger cells. Instead, the two types of cells developed a symbiotic relationship, with the photoautotroph living inside the larger cell. The number of

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Retrieved Text: Why don’t cyanobacteria and bacteria reproduce by mitosis?
Damaged cells of an organism are usually ___ by mitosis.
All the chromosomes in a diploid cell are paired.
How many chromosomes are produced by the first division during meiosis?
Which statement(s) correspond(s) correctly to a mutation?
The kind of cell division associated with an increase in size and weight of an organism is called ___.
Gametes have ___ the chromosome number of the parent cell.
Chromosomes are attached to the ___ during the metaphase of mitosis.
The spindle apparatus disintegrates during the ___ of mitosis.
-Plant cells divide by means of a cell plate.
How does mitosis in animal cells differ from mitosis in higher plant cells?
Occasionally asexual reproduction can cause undesirable proliferation of an organism.
Nearly all plants can be reproduced asexually.
The new plant produced by the technique of layering must remain attached to the stem of the original plant.
A successful scion will produce the product of the rootstock with greater quality.
The technique of asexual reproduction most commonly used in the production of fruit trees is ___.
The vigor of a rootstock is usually ___ than that of the root system produced by the scion.
Asexual reproduction is most common in plants growing in ___ climates.
An elongated, horizontal stem that grows at the surface of the ground or just below it is called a rhizome.
Animals have more mechanisms for asexual reproduction than plants.
The stock is inserted into the scion during grafting.
The most commonly used method of asexual reproduction used in gardening is the cutting.
Root cuttings are more commonly used than stem cuttings.
A ___ is a plant structure with enlarged

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Retrieved Text: Like all plants Toxicodendron diversilobum exhibits an alternation of generations. This means that during the life cycle of the plant it alternates between a multicellular diploid sporophyte generation and a multicellular haploid gametophyte generation. Since the Pacific poison oak is in the phylum Angiosperm it has a dominant sporophyte generation which means that the gametophyte generation will be more dependent on the sporophyte generation.
The first part of the angiosperm life cycle takes place in the flower of the plant. Here in the anther the microsporocytes develop and undergo meiosis which produces haploid microspores. Each microspore undergoes one division of mitosis to form a generative cell and a tube cell. Together they form an immature pollen grain. The generative cells then go through a second mitotic division which produces two sperm nuclei. Inside the ovule one megaspore undergoes meiosis to form four haploid megaspore. Three die off and one remains. The remaining megaspore undergoes three mitotic divisions and generates an 8 nucleate embryo sac also known as a megagametophyte.
Next pollination occurs. The pollen grain germinates on the stigma where a pollen tube grows down into the style. Eventually it grows down into the ovary through the micropyle. One sperm nucleus then fuses with the egg which creates a diploid zygote, and the other sperm fuses with the central cell of the egg to form the endospore.
Now that the embryo has formed it grows inside the embryo sac. The ovule creates a protective seed coat around the embryo and embryo sac. Then the seed is dropped from fruit

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Retrieved Text: Check new design of our homepage! Reproduction is one of the distinguishing features of living organisms, and is essential for the survival of any species. Such perpetuation of species is achieved through two fundamental Reproduce asexually - sexual and asexual. Sexual reproduction involves the formation of a zygote, through the fusion of gametes from two parents.
The zygote develops into an embryo, and grows into an offspring. On the other hand, asexual reproduction involves Reproduce asexually formation of a genetically identical offspring from a single individual. The primitive life forms predominantly exhibit asexual reproduction. The ability to exist in two genders evolved with the changing environment. With the increase in complexity of the newly evolved life forms, the dominance of asexual reproduction decreased.
Nevertheless, each kingdom encompasses a set of strictly asexual organisms, as well as a set of organisms characterized by the presence of both sexual and asexual phases. What is Asexual Reproduction? Asexual reproduction is a reproductive process devoid of gamete formation and fertilization, and mostly proceeds via mitosis. The resultant offspring is a clone of the parent organism due to Reproduce asexually absence Reproduce asexually genetic exchange.
Budding, fission, fragmentation, vegetative propagation, etc. Such reproductive cycles complete in less time, as compared to sexual reproduction, which serves as an evolutionary advantage. However, owing to the lack of genetic variation, the ability to adapt to changing environment is limited.
In asexual organisms, genetic Reproduce asexually can Reproduce asexually only through random mutations. Being so, they are dependent on favorable mutations to cope with environmental changes. List of Organisms

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Retrieved Text: This set contains 67 questions on plant reproduction, anatomy and physiology as well as plant evolution.
A) formation of motile male gametes.
B) alternation of sporophyte and gametophyte generations.
C) presence of both haploid and diploid stages.
Which of the following is NOT a characteristic of plants?
A) Glucose is made from photosynthesis.
B) Cell walls contain cellulose.
D) Diploid and haploid generations alternate in their life cycle.
E) Diploid and haploid phases of their life cycle produce spores.
Cactus plants are adapted to the hot and dry deserts of North and South America. Which of the following characteristics would NOT help cacti to survive the extreme heat and low rainfall?
A) A thick, waxy cuticle.
B) A stem with a small surface area.
C) Stomata that are closed during the day.
D) Thin leaves with a large surface area.
Transport of the products of photosynthesis is understood to occur by pressure flow through the phloem from a source (such as the leaves where the products are produced) to a sink (such as a developing fruit where they are used or stored). Which of the following statements about this transport is FALSE?
A) Water enters the phloem by osmosis.
B) Phloem tubes in a source have a low water pressure.
C) Water and sugar move through the phloem tubes because of pressure.
D) Sugar is removed from phloem by active transport in the sink area.
E) Solutes are pushed along by the flow of water in the phloem.

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Retrieved Text: Life is made up of many special events, one of them is fertilization. It ‘a phenomenon of sexual reproduction, in which two gametes from different species bind to bring the formation of a new cell, which later take the name of the zygote.
There are several cases of fertilization: there is the inner one, in which the male gametes are released directly into the female apparatus, and the external one which is that fertilization which mostly takes place in water, in which the individual releases the gametes so that the another individual may collect them in opportune moments. Finally there is the assisted reproduction in which the union of gametes occur via artificial. But what are the stages of fertilization? Firstly million sperm reach the fallopian Faloppio, which are later attracted the oocyte, but only one of them manages to penetrate the egg, and then finally to fertilize the zygote. As a result of this process is followed by others, such as the development of the embryo, placenta and fetus.
The placenta begins to develop at conception.
It is therefore a vital organ to the fetus, with which it is in close relation. The main task of the placenta to the fetus is to ensure the necessary nutrients for proper development.
The fetus is nothing but the product of “mutations” that the embryo undergoes from the third month. Life is made up of many events, processes unknown to us, we begin to know them without dwelling on what’s appearance.
Previous articleWHAT TIME IS IT?

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Retrieved Text: Which cartoon shows the correct way for the chromosomes to line up at the metaphase plate during mitosis?
What would happen if one chromosome failed to have microtubules from both poles attach?
One daughter cell would not have a copy of that chromosome.
Diatoms are protists that have rigid glass walls. Based on this you can conclude that they carry out cytokinesis similarly to ______________.
What would happen if a cell were unable to properly condense its chromosomes during prophase?
The chromosomal DNA would be subjected to shearing forces, fragmenting the chromosome.
What would happen if cytokinesis occurred before telophase was completed?
A cell that has just exited the G1 phase of the cell cycle (and will eventually go on to divide) will next enter ___________________.
Chromosomes condense and begin to be visible during _____________.
A number of chemical treatments cause microtubules to fall apart. Colchicine (mitonic inhibitor) is one such drug. What would happen if a dividing cell was treated with colchicine?
What would happen to a cell if it went directly from prophase to anaphase (i.e., it failed to undergo metaphase)?
The daughter cells would probably not get equal numbers of chromosomes.
A chimpanzee bone marrow cell, in prophase of mitosis, contains 48 chromosomes. How many chromatids does it contain?
When do homologous chromosomes pair?
Starting with one cell, how many daughter cells will be formed when meiosis is complete?
Sperm cells and ova can be classified as ______________ cells.
How many pairs of homologous chromosomes are found in human males?
The cellular process by which gametes are formed from specialized nonreproductive cells is ________ .
Crossing over occurs during which stage

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Retrieved Text: Gametes are specialised haploid cells that are used to combine and when they do they combine to form a new diploid cell. That process of combination is called fertilization.
Now, you are hopefully familiar with sperm and egg, the two most common kinds of gametes that you've heard of. Where sperm they're small specialized for quick delivery of the DNA to the other cell, the other kind of gamete which is called the egg. Eggs are large. Why are they so large? It allows them to accumulate or store up large amounts of resources to provide for their newly developed diploid cell which will eventually become some new offspring like you and I became came from a single fertalized egg.
We take a look over here we can see in this scale, this thing that looks almost like a planet, that's the egg and you can see how much larger the egg is in size comparison to the sperm. Now if they were both the same size, they would be called isogametes.
We take a look at an isogamete. Every isogamete looks like the other. Now how are iso- how are sperm and egg made different? That happens during the process of either spermatogenesis or oogenesis.
Here we see a generic description of meiosis. The process of making gametes where here we have a cell that has let's suppose four chromosomes. Ultimately it can create four haploid cells. So this is a diploid cell. See it has pairs of homologous chromosomes. These are individual haploid cells, no more do they

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Retrieved Text: Haploid is the term used when a cell has half the usual number of chromosomes. A normal eukaryote organism is composed of diploid cells, one set of chromosomes from each parent. However, after meiosis, the number of chromosomes in gametes is halved. That is the haploid condition.
In humans, the diploid number of chromosomes is 46 (2x23). The number in haploid cells (sperm and eggs) is 23. Some types of animals are haploid, such as male Hymenoptera (ants, bees and wasps). This is a special genetic system called haplodiploidy.
Some plants and animals are polyploid, with more than two sets of chromosomes. For example, one species of wheat is hexaploid, with six sets of chromosomes, although other species of wheat have only two sets. Because so many organisms are diploid, it can become confusing whether haploid refers to one set of chromosomes or more than one. The special term monoploid can be used; it means one set of chromosomes.
Haploid Facts for Kids. Kiddle Encyclopedia.

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Retrieved Text: Spirogyra is a large genus (about 400 species) of freshwater green algae found in shallow ponds, ditches and amongst vegetation at the edges of large lakes, generally growing free-floating. It often grows in short-lived ('ephemeral') ponds that build up during wet weather, and dry up subsquently. Spirogyra is a great favourite of second-level and third-level course, but is a very unusual alga that strictly speaking does not form any gametes and reproduction takes place entirely within the alga.
Cells, 10-100 µm in width, are joined end-to-end in an unbranched, largely unspecialised, stiff filament and are cylindrical with one or two spirally-wound chloroplasts on which many pyrenoids are borne. The cell wall is of two layers, the outer of cellulose and the inner of pectin. Filaments can be several centimeters in length. It generally has a rather silky feel and a shiny green colour.
Most of the interior of the cell is occupied by a large vacuole (a largely water-filled space) in which the central nucleus is suspended by cytoplasmic strands. The chloroplasts wind around in the peripheral cytoplasm.
Asexual reproduction is by fragmentation only. The strands grow until they break, thus forming more individuals. This only takes place under favourable conditions of moisture, temperature, light and nutirent availability.
Sexual reproduction only takes place under adverse conditions, for eample, when the pond dries up. This can be simulated in a dish in the laboratory by allowing a collection dry up gradually over a few days.
Two or more filaments come to lie side by side and projections grow out from cells which

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Retrieved Text: You covered the issue of sexual vs. asexual reproduction, but an interesting question that wasn’t addressed is “Why are there males?” I understand the benefits of gene-sharing, conferred by sexual reproduction, but why does this require sexual dimorphism? One can easily imagine a system where two individuals can share genes without having to be of different sexes. Ursula K. Le Guin envisioned one such possibility in her 1969 novel The Left Hand of Darkness, where individuals can change gender, but especially if we don’t restrict ourselves to viviparous reproduction, why does there even have to be gender? Why does one partner have to contribute the “egg”, and the other the “sperm”? Why not have two equivalent (non-gendered) haploid cells which combine to form a merged offspring (and, speaking of haploid cells, it took me a while to figure out that the word you were tossing around was “ploidy”; a mention of the words “haploid” and “diploid” in the explanation would have helped.)? This ought to double your chances of finding a mate.

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Retrieved Text: Selection can also work at the gene level. When a diploid individual (one that has two copies of its genome) produces haploid gametes (sperm cells or eggs, which have only one copy of the genome), each parental gene has a 50-50 chance of ending up in the gamete population — usually. Sometimes, though, for reasons that are poorly understood, one gene is better than another at making it into the gametes. This phenomenon is selection at the gene level, or meiotic drive.
Meiotic drive occurs when a particular gene has better than a 50 percent chance of making it into the gamete pool and from there to the offspring. Although on its face, selection at the gene level seems to be at odds with how you expect evolution to work, by taking a closer look at meiotic drive, you can see that the same evolutionary forces are at play.

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Retrieved Text: Rescan, Lenormand and Roze (2016) recently published new models on the evolution of life cycles in The American Naturalist.
Most animals and protists have diploid life cycles in which the haploid stage is reduced to a single-celled gamete.
Other organisms, such as charophytes and dinoflagellates, have a haploid life cycle in which the diploid phase is reduced to the zygote and meiosis occurs before any mitotic development.
There’s a third type of life cycle, that regular TME readers may have stumbled across with my posts: haploid-diploidy in which somatic development occurs in both haploid and diploid stages. In seed plants, the haploid stage is rather limited, but in fungi, mosses and macroalgae, the haploid stage is much more important.
[Due to the difference in duration of one phase and the corresponding limits to selection], the problem of the evolution of life cycles (i.e., the relative degrees of development of the haploid and diploid phases) is often recast in terms of the opportunity of selection within each phase.
One model suggests diploids may benefit from the masking of deleterious mutations. But, this assumes deleterious mutations have the same effect in both haploids and homozygous diploids. Recent transcriptomic studies in haploid-diploid species, such as Coelho et al. (2007), have demonstrated some genes are only expressed in one policy and mutations in these genes would have no effect in the other stage as they are not expressed.
Moreover, these genetic models cannot explain the evolutionary stability of haploid-diploid life cycles without considering additional mechanisms, such as ecological niche differentiation (Hughes and Otto 1999).
the interplay between

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Retrieved Text: Abortion is a process of terminating a baby while it is in its mothers stomach. People should be allowed to decide for themselves whether or not they want to terminate their child as it may have been accidental or they may think they can't handle the responsibility. The government should not be able to decide if citizens can go through the process of abortion, as the baby is going to be their responsibility and they may not want that.
Lets be on the same page and go through some definitions.
Murder-the unlawful premeditated killing of one human being by another.
Abortion is the murder of a human. The sole reason is for the mothers benefit and or father. That is evil. There are other ways to handle unwanted humans than killing them which is immoral. The justification my opponent presented for murder is " it may have been accidental or they may think they can't handle the responsibility ". Well, killing the human will benefit the mother so the murder is justified. That is the equivalent of a poor person killing a rich person for money. ( without the rich person knowing or without his ability for self defence) My question is - Should we kill humans?
My opponent argued a embryo is not a human being.
When the two haploid cells( sperm and egg) meet, each with 23 chromosomes, they create a 46 chromosome diploid, zygote. This zygote contains DNA patterns that match many of it's parents DNA patterns. This zygote divides with a unique DNA and creates a embryo

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Retrieved Text: ^ Jump up to: a b William K. Purves, David E. Sadava, Gordon H. Orians, H. Craig Heller (2000). Life: The Science of Biology. Macmillan. p. 736. ISBN 978-0-7167-3873-2. Retrieved March 23, 2018. A single body can function as both male and female. Sexual reproduction requires both male and female haploid gametes. In most species, these gametes are produced by individuals that are either male or female. Species that have male and female members are called dioecious (from the Greek for 'two houses'). In some species, a single individual may possess both female and male reproductive systems. Such species are called monoecious ("one house") or hermaphroditic.

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Retrieved Text: Plants Transpiration involves losing water vapor from aerial parts of plants. Diploid and Haploid Cells Diploid and haploid cells are involved in sexual reproduction of higher eukaryotic organisms. Forests with numerous tree species, and therefore a mix of water-management strategies, appear more tolerant of drought. Ecological Isolation Explained With Examples What is ecological isolation and how does it prevent the occurrence of inter-species hybrids? Natural and artificial selection forms the basis of evolution on this planet. The two stages of meiosis are meiosis I and meiosis. In the 1940s and 1950s, studies regarding genes and DNA progressed to the discovery of the double helical DNA structure. Framing Guide for Article Summaries - how to write a summary for any article. As a result, it makes sweet hot topic birmingham things taste a lot less sweet. Buzzle explains what is a missense mutation and also explains certain examples of disorders that it may cause.
This post explains the basic difference between the two. Mimic each other as a protective measure. Mullerian Mimicry Müllerian mimicry is a survival technique wherein two species that are equally noxious.
Articles in Easy Understandable English for Learners.Articles about biology and biological sciences written by scientists and researchers internationally.
Which will tell you how the cellular life on planet Earth is classified. Read on to know the details. What is a Gene Pool, refer to the following article, this post explains this type of mutation in a comprehensive manner. Refers to the reappearance of an ancestral trait in an individual. When discussing chemosynthesis, and Brown University

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Retrieved Text: The process of meiosis creates 4 haploid gamete cells from a diploid cell. In animals these gametes are called eggs and sperm and in plants they are called eggs and pollen. For meiosis to occur it must go through two divisions, Meiosis I and Meiosis II. During Meiosis, the cell goes through the same stages as Mitosis (Interphase, Prophase, Metaphase, Anaphase, and Telophase/Cytokinesis), but it goes through these phases twice, but with some minor differences.
Creates 4 haploid gamete cells from a diploid cell.
At this point the DNA is in its chromatin form and the DNA replicates.
Homologous Chromosomes (matching chromosomes from mom and dad) join up together and exchange share genetic information. Happens during Prophase I of meiosis.
Matching chromosomes from mother and father. They are the same size, shape and carry genes for the same traits.
The chromosomes line up down the middle along with their homologous pair.
The homologous chromosomes pull apart from one another and move toward opposite poles.
Chromosomes are now at separate poles, nuclear membranes start to form around the 2 sets of chromosomes, and the chromosomes start to unwind back into chromatin. Cytokinesis occurs and the two cells split. These two cells are haploid at this point since each cell contains only 1 of each homologous pair. The next 4 phases occur to each of these cells.
Notice that we skip interphase this time around because there is no replication of DNA between Meiosis I and Meiosis II.
At this point the chromosomes reorganize and the nuclear membranes start to dissolve again. Sister chromatids are joined by

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Input Text: Answer the following question given this paragraph: 

The Nitrogen Cycle Getting nitrogen into the living world is difficult. Plants and phytoplankton are not equipped to incorporate nitrogen from the atmosphere (which exists as tightly bonded, triple covalent N2) even though this molecule comprises approximately 78 percent of the atmosphere. Nitrogen enters the living world via free-living and symbiotic bacteria, which incorporate nitrogen into their macromolecules through nitrogen fixation (conversion of N2). Cyanobacteria live in most aquatic ecosystems where sunlight is present; they play a key role in nitrogen fixation. Cyanobacteria are able to use inorganic sources of nitrogen to “fix” nitrogen. Rhizobium bacteria live symbiotically in the root nodules of legumes (such as peas, beans, and peanuts) and provide them with the organic nitrogen they need. Free-living bacteria, such as Azotobacter, are also important nitrogen fixers. Organic nitrogen is especially important to the study of ecosystem dynamics since many ecosystem processes, such as primary production and decomposition, are limited by the available supply of nitrogen. As shown in Figure 46.17, the nitrogen that enters living systems by nitrogen fixation is successively converted from organic nitrogen back into nitrogen gas by bacteria. This process occurs in three steps in terrestrial systems: ammonification, nitrification, and denitrification. First, the ammonification process converts nitrogenous waste from living animals or from the remains of dead animals.


Q: The nitrogen that enters living systems by nitrogen fixation is successively converted from organic nitrogen back into nitrogen gas by what?

 Choices:

- pollen

- algae

- bacteria

- viruses

A:

Target Text: bacteria

#### Retrieved Documents ####

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Retrieved Text: process in which atmospheric nitrogen is converted to ammonia.
1. The conversion of atmospheric nitrogen into compounds, such as ammonia, by natural agencies or various industrial processes.
2. The conversion by certain soil microorganisms, such as rhizobia, of atmospheric nitrogen into compounds that plants and other organisms can assimilate.
the process by which free nitrogen in the atmosphere is converted by biological or chemical means to ammonia and to other forms usable by plants and animals. Biological nitrogen fixation is the more important process and is accomplished by microorganisms in the soil, either free living or in close association with root nodules of certain plants. In contrast, chemical nitrogen fixation, as is used in industry, requires extremely high temperatures and pressures.
the utilization of atmospheric nitrogen in the synthesis of AMINO ACIDS by some bacteria. Such bacteria can be free-living (e.g. Azotobacter, an aerobe; Clostridium, an obligate anaerobe) while others (e.g. Rhizobium) live in association with plants, occupying swellings in the root called root nodules. The latter relationship is one of SYMBIOSIS, in that the plant gains nutrients and thus can live in nitrogen-poor soils, while the nitrogen-fixer obtains a supply of carbohydrates from the plant. The nitrogen is reduced to ammonia in the microbes by action of the enzyme nitrogenase: N2 + 3 H2 → 2 NH3, the ammonia then reacting with keto acids to form amino acids.
Nitrogen fixation potential of beans (Phaseolus vulgaris L.
Variation in seedling growth, nodulation and nitrogen fixation of Acacia nilotica inoculated with eight rhizobial strains.
Nitrogen fixation and its improvement through genetic engineering.
Nitrogen fixation associated

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Retrieved Text: You are a little tiny nitrogen (N) atom floating around the atmosphere in a gaseous state, the state that you and your nitrogen friends are usually in. You are an element on the periodic table that is very important to life on Earth. You make up DNA, which carries genetic information in organisms.
You also make up about 78% of the air surrounding all living things. The problem is, you like to hang really close to your nitrogen boyfriend in the air, joining together as N2. You have a very strong bond to your nitrogen boyfriend, and the two of you are hard to break apart, which makes you unable to be used by living organisms. That is why you must go through the nitrogen cycle in order to be useful.
The nitrogen cycle is composed of four steps: nitrogen fixation, nitrification, ammonification, and denitrification.
During the first step of the nitrogen cycle, nitrogen fixation, you and your boyfriend (N2) are pulled out of the air by bacteria in the soil. The bacteria turns you both into ammonium by mixing you with hydrogen atoms.
In the next step, nitrification, is the transition of ammonia to nitrite and then nitrate through oxidation. Look at it this way: you start off as a nitrogen atom in ammonium, surrounded by hydrogen atoms. More bacteria in the soil convert you into nitrite and then nitrate, so you are now surrounded by oxygen atoms. As part of nitrate, you can now be brought into plants through their roots in order to be used. You might

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Retrieved Text: Read this article to learn about the nitrogen cycle and the oxygen cycle.
The most abundant element in the atmosphere is nitrogen. In its elemental form it is a colourless and odorless gas which cannot be used by plants or animals. But in combination with oxygen or other elements, nitrogen is available to living organisms as a nutrient. The nitrogen cycle may be defined as the circular flow of nitrogen from free nitrogen gas in the atmosphere to nitrates in the soil, and, finally, back to atmospheric nitrogen.
By this process, nitrogen gas is converted to nitrates.
(i) There are some Nitrogen-fixing bacteria that live in the soil or in nodules on the roots of leguminous plants. They can convert nitrogen gas to nitrate. Nitrogen fixation is also done by some types of blue-green algae and fungi.
(ii) Nitrogen fixation also occurs in the atmosphere. This is natural nitrogen fixation. It takes place when lightning occurs, because the electrical current that passes through the atmospheric nitrogen converts some of the nitrogen gas to nitrogen compounds. These compounds can be used by plants.
(iii) Nitrates are also released from dead and decaying plants and animals and animal wastes.
At the same time, when nitrates are being produced from nitrogen gas, other nitrates are breaking down and releasing nitrogen gas back to the atmosphere. This process of reversal is called de-nitrification.
(ii) When run-off water carry nitrates into surface water which constantly exchanges nitrogen with the atmosphere.
There are some ecosystems where the process of nitrogen fixation and de-nitrification are attuned according to the productivity demands

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Retrieved Text: Let’s talk about nitrogen. What is nitrogen, and why does it matter to us?
Nitrogen is chemical element number 7. It’s crucial to living organisms. It’s a necessary component in amino acids, the building blocks of proteins. While it’s common knowledge that proteins make up muscles, they also perform a wide variety of functions and are involved in virtually all cell processes that keep you alive.
Nitrogen is also a component of nucleic acids in DNA, the blueprint of life. DNA determines your eye color, your height, your metabolism, even to an extent your intelligence and behavior. Clearly, living organisms require nitrogen to survive.
Eye color is determined by DNA, made from proteins built up with nitrogen.
In many types of ecosystems, however, there is a scarcity of usable nitrogen. Nitrogen has a limited availability for biological use. Yet, nitrogen is the most abundant element in the earth’s atmosphere. 78% of the air around us consists of nitrogen in the form N2.
78% of the atmosphere is composed of N2.
How do you explain this apparent dichotomy between abundant atmospheric nitrogen, and the scarcity of nitrogen in ecological systems?
While abundant, atmospheric nitrogen is in the form N2. Other significant forms of nitrogen in ecosystems are ammonia (NH3), nitrite (NO2-), and nitrate (NO3-).
Nitrogen from animal waste is excreted in the form of ammonia. Plants intake nitrogen in the form of nitrate. From N2 in the atmosphere to nitrate absorbed as nutrients by plants, nitrogen is converted through different chemical forms by ecological processes and cycled over and over again.
These processes compose the nitrogen

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Retrieved Text: Carbon Cycle VIDEO by FUSE SCHOOL!
What in the world is BIOGEOCHEMICAL RECYCLING?
YOU SHOULD BE ABLE TO..
These cycles are different from the energy cycles of the food chain and food web in whic h the Energy Flow through the ecosystem flows in ONE DIRECTION. Also some of this energy gets lost from “the system” as heat.
These five cycles are particularly important to organisms because these materials make up the chemical compounds of cells.
THE CARBON CYCLE is the global circulation of carbon from the environment to living organisms and from living organisms back to the environment. Carbon EXISTS in the abiotic environment as 1) Carbon dioxide [CO2 (gas)] in the atmosphere, 2) dissolves in H2O to form HCO3 (BICARBONATE) and Carbonic Acid (H2CO3)., 3) Carbonate rocks (limestone & coral = CaCO3 [Calcium Carbonate], 4) Deposits of coal, petroleum, and natural gas which are derived from once living things (fossil fuels), and 5) Dead organic matter.
The Carbon Cycle Step 1 - Carbon enters the atmosphere as carbon dioxide from respiration (breathing) and combustion (burning).
The Carbon Cycle Step 2 - Carbon dioxide is absorbed by producers (life forms that make their own food e.g. plants) to make carbohydrates in photosynthesis . These producers then put off oxygen.
The Carbon Cycle Step 3 - Animals feed on the plants. Thus passing the carbon compounds along the food chain. Most of the carbon these animals consume however is exhaled as carbon dioxide. This is through the process of respiration. The animals and plants then eventually die.
The Carbon Cycle Step 4 - The dead

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Retrieved Text: Provide an example of an ecosystem evolving in a manner that preserves or recycles nutrients.
In tropical environments with stable geological topography, there is very little phosphorus in the soil. This is due to the age and stability of the soil. The soil itself is so old that the clays in it have broken down. Because rain is the only input of water, there is no opportunity for the addition of new minerals. The phosphorus necessary to sustain the ecosystem is stored in the vegetation, and is retained phosphorus during growth. When those plants die, the return the phosphorus to the ecosystem in the form of plant litter detritus, and is quickly taken back up into other organisms in the system. The other organisms in the environment have evolved to pull the phosphorus directly out of the litter instead of the soil.
How is it that a nutrient like nitrogen, which is typically qualified as limiting, is present in such excess in many locations?
Nitrogen is historically not easily obtained in natural systems. It exists primarily as N2 gas in the atmosphere and plants are not able to obtain this form directly. Most plants rely on other organisms to fix nitrogen into usable forms like NH4+ and NO3- which they are able to use. This means that the plants are dependent primarily on microorganisms in the soil or in their root structures thus their growth is limited by the productivity of the microorganisms.
Humans have changed this case in three ways. Humans cultivate a variety of plants such as legumes

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Retrieved Text: I don’t know what it is, but I love falling asleep to the sound of a thunderstorm. Not the violent storms mind you! Those can be quite scary and I prefer not having to hunker down in the basement! No, I’m talking about the ordinary, “garden-variety” thunderstorms. There’s just something about laying there listening to the steady patter of rain as it hits the ground, then seeing a blue-white flash of light brighten the sky and you count the seconds until you hear the thunder rumble, that I find soothing.
But why do we have thunderstorms? What’s the matter with just rain?
Everybody knows that plants need water to survive, but did you know that they also need nitrogen? In fact, we all do. ALL living organisms need it to survive. It’s an important part of proteins and amino acids. We get it from eating plants, but where do plants get it?
Nitrogen makes up about 78% of our air. Unfortunately, it is in gas form. Plants need it in mineral form, but that is not as abundant. In order for plants to use nitrogen, it first must be converted by a process called nitrogen fixation.
Plants that are a part of the legume family, such as clover, beans and peas, are able to fix nitrogen in this way and are important in reintroducing nitrogen to the soil where other plants can access them. Unfortunately, unlike legumes, other plants are not able to do so. And what happens if they’re not sitting next to one of their nitrogen-fixing neighbors? Here

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Retrieved Text: The work, carried out at Ulsan National Institute of Science and Technology (UNIST) in South Korea and published in Scientific Reports, could be a step towards replacing conventional platinum (Pt)-based catalysts for energy conversion.
The search for economically viable alternatives to fossil fuels has attracted attention among energy communities because of increasing energy prices and climate change. Solar cells and fuel cells are to be promising alternatives, but Pt-based electrodes are expensive and susceptible to environmental damage.
Nitrogen fixation is where nitrogen (N2) in the atmosphere is converted into ammonia (NH3). Fixation processes free up nitrogen atoms from their diatomic form to be used in other ways, but nitrogen does not easily react with other chemicals to form new compounds.
The UNIST team previously reported that dry ball-milling can efficiently produce chemically modified graphene particles in large quantities*. This research, in Scientific Reports, presents another innovation to improve the materials. Along the way, the research team discovered a novel nitrogen fixation process.
They focus on modifications with nitrogen, developing a technique with direct nitrogen fixation, carbon-nitrogen bond formation, at the broken edges of graphite frameworks using ball-milling graphite in the presence of nitrogen gas.
The research was led by Jong-Beom Baek, professor and director of the Interdisciplinary School of Green Energy/Low-Dimensional Carbon Materials Center, UNIST, Liming Dai, professor of Case Western Reserve University and Noejung Park, professor of the Interdisciplinary School of Green Energy, UNIST.
"Nitrogen is the most abundant constituent in air and it is inert diatomic gas while graphite is the most thermodynamically stable form of carbon allotropes," said Prof.

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Retrieved Text: Why are artificial nitrogen fertilisers used and how do they affect sustainability?
In many natural environments nitrogen is the primary factor in limiting plant growth (provided there is sufficient water supply and an absence of pests and disease). It is an essential macronutrient for plant metabolic pathways, protein synthesis and is a major component of chlorophyll. Although nitrogen accounts for 78% air, plants can only utilise reduced sources of this element such as the inorganic forms of ammonium (NH4–) and nitrate (NO3–) salts from soil. In order to become available for uptake, plants rely on a process of nitrogen fixation which is carried out naturally by fixation microorganisms. Some nitrogen fixing bacteria symbiotically associate with particular plant groups such as rhizobium bacteria and legumes. Despite this only about 2% of soil nitrogen is naturally found in inorganic form.
As with any business, farmers seek to maximise profit and typically in cropping systems this equates to optimising yield. In wheat systems, high yields of high quality grain (i.e. high % nitrogen content) requires high input and uptake of nitrogen (Barraclough et al., 2010). Whilst grain and fertiliser price ratios are favourable, farmers are driven to apply high levels of nitrogen above those that are most efficient for crop stability in an effort to maximise potential yields and returns.
The process of nitrogen fixation is energy intensive since it requires the breaking of the triple covalent bond of N2 and as in nature, the industrial manufacture of nitrogen fertilisers requires significant amounts of energy to break the bonds of N2 molecules.

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Retrieved Text: Humans affect the nitrogen cycle through activities that increase the amount of nitrogen that is biologically available in an ecosystem. The major culprits are fossil fuel combustion and the application of nitrogen-based fertilizer. Fossil fuel combustion releases nitric oxides and combines with other elements in the air to form smog and acid rain.
The US National Library of Medicine reprinted a study by Scott Fields that concludes humans inject nitrogen compounds into the air in ever increasing quantities, causing serious impacts on biodiversity, human health, water quality, global warming and also the rate of population growth in developing nations.
Most scientists agree that humans disrupt the nitrogen cycle by altering the amount of nitrogen stored in the biosphere. Burning fossil fuels results in a change in carbon storage, thus affecting the nitrogen cycle and other vital processes. It adds nitrogen to terrestrial ecosystems and leads to nutrient imbalance in trees, a decline in biodiversity, and changes in the health of forests.
Moreover, agricultural systems use fertilizers to improve plant production. Unused nitrogen, typically in the form of nitrate, tends to enter rivers and streams and eventually reach people’s drinking water. It also enters coastal marine systems near the shore and causes anoxia, which means no oxygen, and hypoxia, which means low oxygen. It alters biodiversity, degrades habitat and changes the food-web structure.
An increase in the availability of nitrogen usually limits the productivity of both terrestrial and aquatic systems. Due to human activities, industrial nitrogen fixation has exponentially increased over the years.
How Do Humans Affect the Carbon Cycle?

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Retrieved Text: Dr. Gina Holguin who participated in the development of this technique.
Why do we need this technique?
The heavy nitrogen non-radioactive isotope (15N2) is often used as a label for nitrogen fixation experiments, in which it is desirable to monitor directly the rate of nitrogen fixation and the destination of the resulting metabolites in an organism or ecosystem. This is one of the most acceptable and reliable techniques for this purpose, and it has been used for decades.
Heavy nitrogen gas can be purchased in a pressurized cylinder, or produced in the laboratory with specialized equipment. However , both methods of obtaining the gas are expensive, and for some laboratories, particularly those in developing countries, this represents an insurmountable obstacle to their research. These methods of obtaining the gas also introduce a complication, because a typical nitrogen fixation experiment requires samples of gas at atmospheric pressure. The pressure must be reduced with a pressure regulator in the case of gas in a pressurized cylinder, and traditional laboratory methods produce heavy nitrogen at pressures well below atmospheric that are not generally suitable for direct use in nitrogen fixation experiments. This is because there is no easy way in which to equalize the gas to atmospheric pressure for subsequent injection into a sample bottle.
Previously, a simple technique was developed in Australia by Wood and Kennedy (2001) to produce 15N2 gas at a research laboratory involved in biological nitrogen fixation research (not a specialized chemical production facility). This technique, and the modification to it described here, are both limited by the volume

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Retrieved Text: To what extent can a mixed farm be self sufficient in nitrogen by growing nitrogen-fixing legumes and recycling animal manures? An opportunity to examine this question was provided by an upland farm in the Annapolis Valley of Nova Scotia where faba beans (Vicia faba L. minor) were grown on 1/3rd of the cultivated land, grains from cereals and faba bean were fed to laying hens and the manure was applied to cereals. The farmer had ceased to apply commercial fertilizers and herbicides after 1975, thinking that inputs of N (nitrogen) via legume nitrogen fixation should be sufficient, and that weeds could be adequately controlled by mechanical means. His cereal yields fell abruptly, apparently because of insufficient N. Was the apparent N deficiency due to low nitrogen fixation in faba beans and/or to high losses via leaching, export of N from the farm in eggs, ammonia volatilization, denitrification and/or to excessive weeds? To address this question, in 1978-79 we examined patterns of faba bean root+nodule nitrogenase activity, leaf nitrate reductase activity and N accumulation and removals in faba bean on this upland farm and on a nearby dykeland farm. The total N input via N2 fixation was estimated by applying a reported ratio of acetylene reduction to N2 fixation, and by comparison of N accumulation in faba bean with that in non-legume plots. Observations on crop and weed biomass and N content, manure N, soil nitrate and ammonia volatilized after application of manure to microplots were conducted on the upland farm; denitrification in soil cores on the

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Retrieved Text: The Crop Monitoring Program is a carefully designed plan which enables growers to check systematically the status of the nutrients in their plants and act accordingly. By following this program, growers can obtain vital information about the nutrient levels of plants during the critical growing cycles and add or modify the fertilizer intakes of their plants to maximize the yields.
Peat or sandy soil nutrients are easy to leach or wash out from the cranberry bogs. Nitrogen is a nutrient which is contained in soils and sediments chiefly as a complex organic substance in the form of ammonia, molecular nitrogen, and nitrate. It needs to be monitored often because of its variable nature. Due to fluctuations in moisture and temperature of the soil, nitrogen loss can take place through leaching, volatilization of ammonia, or denitrification. Loss of other nutrients can also occur. But deficiencies of some nutrients like sulfur, boron, and molyb denum are hard to recognize visually. However, a complete tissue analysis can often detect a nutrient deficiency before symptom appear in the plant.
Diagnosis of "hidden hunger" can be followed by a proper treatment by observing tissue crop monitoring program. It has been found that once the symptoms of nutrient deficiency appear in the plant, it is usually too late to avoid production loss. Therefore, a crop monitoring program, like the one administered by K Laboratories, is very crucial to healthy growth and production of plants.
How Many Crop Monitoring Programs are Available?
K Laboratories offers intensive crop monitoring programs for various crops including ginseng, blueberry, strawberry, cranberry,

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Retrieved Text: Nitrogen exists in nature in several oxidation states: N(-III) as in NH3, NH+, and various organic compounds; N(III) in nitrites, NO- , and N(V) in nitrates, NO- as well as N(0) in N2 in addition to other formal oxidation states in oxides of which nitrous oxide (N2O), nitric oxide (NO), and nitrogen dioxide (NO2), are most important environmentally.
The elemental form N2 contains a triple bond with a large bond energy (946kJ/mol). Consequently, reactions that require the N—N bond to be broken are likely to take place with difficulty, even if the overall energy change of the reaction is favorable. As a result, N2 is relatively inert. Some of its most important environmental reactions are produced by microorganisms, which can provide a reaction mechanism of low activation energy to convert N2 to ammonia and amines.
These reactions depend on pH, and the equilibrium composition of a nitrogenous system depends on this as well as on the redox potential pE of the system (Section 9.4). Nitrite has a comparatively narrow range of pE over which it can exist at significant concentrations (Figure 10-5); most commonly the stable forms of nitrogen are NH+ or ammonia in reducing environments, and NO-in oxidizing ones. At pH ranges near neutrality, the NO2- stability region lies near pE 6.5.
The essential features of the nitrogen cycle are shown in Figure 10-6. There are several processes of importance.
FIGURE 10-5 The relative concentrations of the nitrogen species in solution as a function of pE at pH 7.
FIGURE 10-6 The nitrogen cycle. Terms are defined later in the

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Retrieved Text: The overarching goal of the Tezcan Lab is to create and understand biological complexity through chemical and protein design approaches. Our research is motivated by the fact that proteins are the most versatile building blocks for the construction of biological machines (e.g., photosystem II, nitrogenase and cytochrome c oxidase) and advanced scaffolding materials (e.g., collagen superstructures, microtubules, viruses) that provide the necessary molecular components to sustain the complexity of living systems. However, the ability of laboratory scientists to control the self-assembly of proteins or to use them as synthetic building blocks has been limited owing to the chemical and structural complexity/heterogeneity of protein molecules. Inspired by fundamental principles of inorganic coordination chemistry and supramolecular chemistry, our group develops new chemical strategies for the construction of complex protein assemblies with sophisticated structures and physicochemical properties, and integrate such systems into living systems.
In parallel, we are interested in understanding the molecular details of biological nitrogen fixation. The conversion of molecular nitrogen into bioavailable forms such as ammonia is essential for the biosynthesis of amino and nucleic acids, as well as the production of fertilizers and countless industrial chemicals. The extreme conditions required by the industrial nitrogen fixation processes, however, translate into an immense dependence on fossil fuels and account for 1-2% of all human energy consumption. Our goal in this project is to elucidate the molecular mechanism of nitrogenase, a redox-metalloenzyme that catalyzes nitrogen fixation at ambient conditions. In particular, we aim to understand why and how ATP-hydrolysis is involved in nitrogen fixation, and use this knowledge to

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Retrieved Text: Many present-day coffee plantations use chemical fertilizers, especially nitrogenous and phosphatic ones. These types of fertilizers are bad for two main reasons: they are very expensive, and these chemical fertilizers often make use of non-renewable energy resources like fossil fuels, which can deplete nature’s precious resources. Furthermore, these synthetic fertilizers can harm Mother Earth due to water pollution. Thus, these chemical fertilizers are disastrous for the fragile ecology of coffee-growing regions.
Many generations of coffee farmers have ignored and abused the soil. The soil imbalance process takes time and the changes in each generation are minute, so no one cared – and many people still don’t care. Now, many farmers need to enrich the soil, so they turn to chemical fertilizers. The core issue for farming is how can we foster development and production without negatively affecting environment?
Faced with a problem of such a enormous magnitude, one can find a easy, yet effective solution for fertilizer needs of Coffee Plantations by just looking at the soil as a major natural resource. Most people think of soil as a dead, inert material. However, from an agricultural standpoint a healthy soil is the lifeline of any nation.
Soil itself is a living system with millions of beneficial microbes, acting as factories that provide biological nitrogen and other nutrients to the plant. Consider that 83.3% of the earth’s atmosphere is made up of inert nitrogen gas. Microorganisims can convert this atmospheric nitrogen and make it available to the plant in the soluble form (such as ammonia) that the plant can absorb

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Retrieved Text: Subjects Eutrophication--Florida. ; Water--Nitrogen content. ; Nitrogen--Fixation.
Collation x, 167 pages : illustrations ; 27 cm.
1. Conclusions -- 2. Recommendations -- 3. Introduction -- 4. Review of the nitrogen cycle in natural waters -- 5. Transport of nitrogen into lakes -- 6. Nitrogen fixation as an in situ nitrogen source for natural waters. I, Algal fixation in lakes -- 7. Nitrogen fixation as an in situ nitrogen source for natural waters. II, Bacterial fixation in lakes and sediments -- 8. Other in situ nitrogen sources and sinks -- 9. Analytical investigations -- 10. Acknowledgements -- 11. References -- 12. Publications and patents -- 13. Appendix. Sources of nitrogen were reviewed to determine their significance in lacustrine budgets. Nutrients in rainfall were found significant although their variability obviates precise conclusions. Using literature values for nutrient export from various land uses, nutrient budgets were calculated for 55 Florida lakes. Critical N and P loading rates (above which eutrophication is likely) were estimated from the calculated budgets and lake trophic conditions. Algal fixation in two eutrophic Florida lakes was studied in detail; the total amount of N fixed and factors affecting the occurrence of fixation were evaluated. A survey of fixation in 55 Florida lakes showed significant fixation only in eutrophic lakes. Bacterial fixation in the anoxic hypolimnion of a small lake contributed substantial nitrogen to the lake, and N fixing activity was found in both estuarine and lacustrine sediments. The acetylene reduction assay for N fixation was evaluated; short incubations were found essential. Reduction was light-dependent and N2 acted

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Retrieved Text: The author is Principal Scientist, Centre for Environment Science and Climate Resilient Agriculture, Indian Agricultural Research Institute, New Delhi. hpathak.iari@gmail.com.
Nitrogen fertiliser has increased food production tremendously all over the world. However, it also contributes to climate change through emission of nitrous oxide and other greenhouse gases. Efficient management of nitrogen offers opportunities for climate change adaptation and greenhouse gas mitigation.
Nitrogen is the most limiting nutrient controlling the primary production of all agricultural systems. Intensively cultivated systems, therefore, require exogenous application of nitrogen both in inorganic and organic forms. Worldwide, use efficiency of external nitrogen supplied is as low as 33 per cent (J K Ladha, et al., 2005, ‘Efficiency of fertiliser nitrogen in cereal production: retrospects and prospects’, Journal of Advances in Agronomy), while the unaccounted for 67 per cent represents loss of nitrogen fertiliser from agricultural systems and is a cause of serious concern. Soil nitrogen dynamics is an integral component of the global nitrogen cycle. A single nitrogen molecule (N2) introduced anywhere in system can have cascading effects in various parts of the environment, after it has been converted to reactive nitrogen forms, such as ammonia (NH3), nitrogen oxides (NOx), nitrous oxide (N2O), nitrate (NO3-), urea, amines, proteins and nucleic acids. Nitrous oxide, as a greenhouse gas is responsible for global warming and climate change (Fig. 1).
The objective of this article is to assess the role of nitrogen use in gaseous-N emission from Indian agriculture and assess its mitigation options.
Agricultural activities have greatly altered the global nitrogen cycle and produced nitrogenous gases of environmental

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Retrieved Text: FIGURE 11.3 Nitrogen dynamics in a stream ecosystem. Bioavailable inorganic nitrogen consists mainly of nitrate and ammonia, which is immobilized by autotrophs and microbial heterotrophs in biofilms or in suspension, and by higher plants. Assimilatory uptake refers to nutrients that are incorporated into cellular constituents and are potentially available to higher trophic levels. Excretion, decomposition, and production of exudates are the principal pathways by which elements are recycled to an inorganic state. Various dissimilatory transformations of inorganic forms of nitrogen by bacteria add to the complexity of the nitrogen cycle. Cyanobacteria and other microorganisms capable of nitrogen fixation transform N2 gas into ammonia. Nitrification, which takes place under aerobic conditions, and denitrification, which takes place under anaerobic conditions, further influence the quantities and availability of dissolved inorganic nitrogen (DIN).
the central role of bacteria in its transformation from one form to another. To understand the complexities of the N cycle, it helps to recognize that some transformations are to obtain N for structural synthesis (assimilatory uptake), while others are energy-yielding reactions (dissimi-latory uptake). Nitrogen fixation and assimilation of DIN by autotrophs and heterotrophs are in the former category, whereas nitrification and denitrification are reactions where bacteria obtain energy by using ammonia as a fuel or nitrate as an oxidizing agent.
Primary producers rely primarily on the surrounding water to supply the nutrients needed for protein synthesis. Bacteria and fungi can meet much of their nutrient requirements from their C substrate, but when that substrate is poor in nutrients, these microorganisms also rely on nutrients in the water. Biological

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Retrieved Text: Uncertainty in the global patterns of marine nitrogen fixation limits our understanding of the response of the ocean’s nitrogen and carbon cycles to environmental change. The geographical distribution and ecological controls on nitrogen fixation are difficult to constrain with limited in-situ measurements. Here we present convergent estimates of nitrogen fixation from an inverse biogeochemical and a prognostic ocean model. Our results demonstrate strong spatial variability in the nitrogen to phosphorus ratio of exported organic matter that greatly increases the global nitrogen-fixation rate. We find that new nitrogen supports up to 50% of export in subtropical gyres, that nitrogen fixation and denitrification are spatially decoupled and that current-era nitrogen sources and sinks largely balance on multidecadal timescales. Moreover, we propose a role for top-down grazing control in shaping the global patterns of nitrogen fixation. Our findings suggest higher than expected ocean carbon export and weaker stabilizing nitrogen-cycle feedbacks than previously thought.
Francois Primeau is a Professor of Earth System Science at the University of California, Irvine. His research is at the interface between physical oceanography and biogeochemistry where he develops computational methods to make better inferences from data and models about the physical and biogeochemical state of the ocean.

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Retrieved Text: Nitrogen reduction (or "fixation") has been a longstanding target of study in chemistry because of the compelling goal of utilizing abundant, cheap atmospheric nitrogen for chemical synthesis. Current methods reduce nitrogen to ammonia at high temperatures and pressures. This seminar will discuss our research into low-temperature nitrogen fixation, as well as new mechanisms that lead to organic products from nitrogen. One of our strategies borrows from the natural enzyme, nitrogenase, which uses an unusual iron-sulfur cluster whose atomic-level mechanism is mysterious. This motivates the development of iron-sulfur complexes with unusual shapes, and study of their interactions with nitrogen and other nitrogenase substrates. Another strategy involves low-coordinate iron coordination compounds, which display new mechanisms for breaking the N-N bond of nitrogen. Studies on low-valent iron compounds have led to the first example of converting nitrogen and arenes directly into aniline products.

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Retrieved Text: Bacteria that able to convert nitrogen gas from the atmosphere into nitrous compound accessible by plants are called nitrogen-fixing bacteria. These bacteria are found both in the soil and in symbiotic relationships with plants. Their capability to convert nitrogen into ammonium compound is associated with specific enzymes in the cell. This ability completes the Nitrogen Cycle on Earth and it is believed that 90% of nitrogen fixation occurs through biological method.
Two kinds of nitrogen-fixing bacteria are recognized. The first kind, the free-living (non-symbiotic) bacteria, includes the cyanobacteria (or blue-green algae) Anabaena and Nostoc and genera such as Azotobacter, Beijerinckia, and Clostridium. The second kind comprises the mutualistic (symbiotic) bacteria; examples include Rhizobium, associated with leguminous plants (e.g., various members of the pea family); Frankia, associated with certain dicotyledonous species (actinorhizal plants); and certain Azospirillum species, associated with cereal grasses.
The symbiotic nitrogen-fixing bacteria invade the root hairs of host plants, where they multiply and stimulate formation of root nodules, enlargements of plant cells and bacteria in intimate association. Within the nodules the bacteria convert free nitrogen to ammonia, which the host plant utilizes for its development. To ensure sufficient nodule formation and optimum growth of legumes (e.g., alfalfa, beans, clovers, peas, soybeans), seeds are usually inoculated with commercial cultures of appropriate Rhizobium species, especially in soils poor or lacking in the required bacterium.
Due to the many positive feedbacks obtained for RealStrong fertilizer formulations, All Cosmos Industries have set up and exclusive research center in Malaysia on the different microorganisms in RealStrong fertilizers. RealStrong fertilizers are manufactured based

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Retrieved Text: One of the objectives and targets of the project is to preserve the soil used for crops destined to human consumption thanks to the development of novel practices of alternate cultivation of legumes to replenish and optimize the soil nitrogen before a new wheat crop.
The project will investigate the saving achieved through nitrogen fixation, analysing the fertilizer required for growing the subsequent wheat crop cycles, incorporating biological nitrogen fixation into the bioenergy cycle. The project will compare the crop yields in two successive years, evaluating the amount of wheat grains produced in the presence of a reduced use of fertilizers supported by nitrogen enrichment of natural source (nitrogen fixing rhizobia).
Legume-supported rotations are used in many countries such as China and India, and have returned to the forefront in Canada and Australia. Rotation of soil use is an optimum practice to reintroduce nitrogen without using costly chemical fertilizers. However rotations have only been studied for soybeans and this will be a pilot study using chickpeas. Grain legume crops are usually incorporated into crop rotations every 3-6 years in a limited zone of central Europe, and the present experiments extend to all the pedoclimatic zones of Europe. The existence of many benefits of legumes to the cropping system, however, suggests that some of the benefits are either not known to or not valued by the grower. Life Cycle Analysis has, on a limited scale, already helped to breach this gap and now needs to be extended into many more regions of Europe, to put monetary values on some

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Retrieved Text: An important and economic source of nitrogen for Mediterranean crop and forage systems arises from symbiotic nitrogen fixation, which contributes also to a high environmental protection and sustainability.
This papers refers on the quantification of nitrogen fixation in sweetvetch, by the isotopic dilution and nitrogen balance methods. In addition, the effect of sweetvetch inoculation with a Sardinian strain of Rhizobium sullae was evaluated against an uninoculated treatment.
The potential of nitrogen fixation in sweetvetch, estimated by the isotopic dilution method, resulted high, reaching 180 kg ha-1 of nitrogen fixed in the biennium. The nitrogen balance method underestimated the nitrogen fixation compared to the isotopic dilution.
Very low differences between inoculated and uninoculated sweetvetch were due to a presence of resident rhizobia in the soil. This result outlines the need of evaluating where inoculation is necessary or useless.

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Retrieved Text: Michigan Tech rented a HD camera (same model as the ones used for filming the “Hobbit” movie). We also set up some photo shoots in Dr. Werner’s lab and the Medical Laboratory Science teaching lab with Brigitte Morin and Karyn Fay.
Amy Marcarelli (Bio Sci) is one of the authors of A critical assessment of the ecological assumptions underpinning compensatory mitigation of salmon-derived nutrients. In the May online issue of Environmental Management.
Marcarelli, Ashley Coble (GLRC) and Evan Kane (SFRES) authored Ammonium and glucose amendments stimulate dissolved organic matter mineralization in a Lake Superior tributary in the Journal of Great Lakes Research.
Earlier this month, Coble also had another paper, Strontium source and depth of uptake shifts with substrate age in semiarid ecosystems, published in the Journal of Geophysical Research – Biogeosciences based on her MS research at Northern Arizona University.
Photographs and details of awards and fellowships coordinated by the Graduate School can be found online.
Casey Huckins, (Bio Sci/GLRC) is the principal on a research project that received a $331,979 research grant from the Michigan Department of Natural Resources. The project is titled, Innovative and Multifaceted Control of Invasive Eurasian and Hybrid Watermilfoil Using Integrative Pest Management Principles.
Also involved in the project are Amy Marcarelli (Bio Sci), Erika Hersch-Green (Bio Sci) and Colin Brooks (Michigan Tech Research Institute).
Photos from Spring 2015 graduation.
She’s looking at two biological processes: nitrogen fixation and denitrification. Nitrogen fixation is sort of like a magic show where microbes take nitrogen out of thin air, turning it into a usable form for all organisms. The trick

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Retrieved Text: Describe the short term cycling of carbon through the processes of photosynthesis and respiration.
Identify carbon sinks and carbon sources.
Describe short term and long term storage of carbon.
Describe how human actions interfere with the natural carbon cycle.
Carbon is a very important element to living things. As the second most common element in the human body, we know that human life without carbon would not be possible. Protein, carbohydrates, and fats are all part of the body and all contain carbon. When your body breaks down food to produce energy, you break down protein, carbohydrates, and fat, and you breathe out carbon dioxide.
Carbon occurs in many forms on Earth and is found throughout the environment (Figure below). The element moves through organisms and then returns to the environment. When all this happens in balance, the ecosystem remains in balance too. In this section, let’s follow the path of a carbon atom over many years and see what happens.
These are some of the structures that carbon takes.
Nitrogen is also a very important element, used as a nutrient for plant and animal growth. First, the nitrogen must be converted to a useful form. Without “fixed” nitrogen, plants, and therefore animals, could not exist as we know them.
The short term cycling of carbon begins with carbon dioxide (CO2) in the atmosphere.
The production of food energy by land plants.
Plants and animals engage in the reverse of photosynthesis, which is respiration. In respiration, animals use oxygen to convert the organic carbon in sugar into food energy they can use. Plants also go through

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Retrieved Text: Two relatively recent independent developments stand behind the current major research effort on nitrogen fixation, the process by which bacteria symbiotically render leguminous plants independent of nitrogen fertilizer. The one development has been the rapid, sustained increase in the price of nitrogen fertilizer. The other development has been the rapid growth of knowledge of and technical sophistication in genetic engineering. Fertilizer prices, largely tied to the price of natural gas, huge amounts of which go into the manufacture of fertilizer, will continue to represent an enormous and escalating economic burden on modern agriculture, spurring the search for alternatives to synthetic fertilizers. And genetic engineering is just the sort of fundamental breakthrough that opens up prospects of wholly novel alternatives. One such novel idea is that of inserting into the chromosomes of plants discrete genes that are not a part of the plants’ natural constitution: specifically, the idea of inserting into nonleguminous plants the genes, if they can be identified and isolated, that fit the leguminous plants to be hosts for nitrogen-fixing bacteria. Hence, the intensified research on legumes.
Nitrogen fixation is a process in which certain bacteria use atmospheric nitrogen gas, which green plants cannot directly utilize, to produce ammonia, a nitrogen compound plants can use. It is one of nature’s great ironies that the availability of nitrogen in the soil frequently sets an upper limit on plant growth even though the plants’ leaves are bathed in a sea of nitrogen gas. The leguminous plants—among them crop plants such as soybeans, peas, alfalfa, and clover—have solved the

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Retrieved Text: We report the discovery of novel subcellular structures related to bacterial nitrogen fixation in the strictly respiratory diazotrophic bacterium Azoarcus sp, BH72, which was isolated as an endophyte from Kallar grass, Nitrogenase is derepressed under microaerobic conditions at O-2 concentrations in the micromolar range. With increasing O-2 deprivation, bacteria can develop into a hyperinduced state, which is characterized by high specific rates of respiration and efficient nitrogen fixation at approximately 30 nM O-2 Ultrastructural analysis of cells in the course of hyperinduction revealed that complex intracytoplasmic membrane systems are formed, which consist of stacks of membranes and which are absent under standard nitrogen-fixing conditions, The iron protein of nitrogenase was highly enriched on these membranes, as evidenced by immunohistochemical studies, Membrane deficiency in NifH/K- mutants, a deletion mutant in the nifK gene and the character of NH4+-grown cells suggested, in concert with the membrane localization of nitrogenase, that these structures are specialized membranes related to nitrogen fixation. We propose the term 'diazosomes' for them, Development of intracytoplasmic membranes coincides with the appearance of a high-molecular-mass form of the iron protein of nitrogenase, which was detectable in membrane fractions, Mutational analysis, and determination of the N-terminal amino acid sequence indicate that the nifH gene product is covalently modified by a mechanism probably different from adenosine diphosphoribosylation. Development of diazosomes in nitrogen-fixing cells can be induced in pure cultures and in co-culture with a fungus isolated from the rhizosphere of Kallar grass.
Hurek, Thomas, Marc Van Montagu, Eduard Kellenberger, and Barbara Reinhold-Hurek. 1995. “Induction of Complex Intracytoplasmic Membranes Related

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Retrieved Text: Crop treatment practices have a possible effect on nitrogen and carbon cycling as nitrogen and carbon are used as plant nutrients. As part of the denitrification process in the soil, nitrous oxide, a greenhouse gas, is released into the atmosphere. By evaluating the amount of greenhouse gases released by specific crop management practices, a reduction in the amount of greenhouse gases released can be developed in future agricultural systems. Crop treatment of miscanthus, switchgrass, maize, prairie, and sorghum were varied to determine the effects of differing levels of nitrogen fertilizer treatment. The effects on nitrogen and carbon cycling of the different crop management practices were measured by determining the total organic carbon in a sample, the level of greenhouse gas emission, and the amount of ammonium and nitrate in the soil sample. This project’s outcomes may increase understanding of soil carbon and nitrogen cycling and greenhouse gas emission from the soil. The type of crop and type of fertilizer have strong impacts on the pathways for nitrogen loss and carbon availability.
Orenstein, Emily, "Nitrogen and Carbon Cycling of Sustainable Agricultural Methods in Second Generation Biofuel Grasses" (2014). Chemistry and Physics Undergraduate Theses. 10.

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Retrieved Text: Copy to Clipboard Experienced and driven Compliance Officer with a proven track record of helping to lead companies by ensuring they are functioning in complete compliance with all national and international rules and regulations.
If students can draw a picture of the problem even using simple representations like squares or circles for the units discussed in the problemthen it can help them visualize exactly what's occurring.
Pada tahunkebanyakan dari perangkat lunak yang mereka miliki bebas karena mereka tidak berpikiran untuk membatasinya. Para pengguna hanya menerima berkas berupa deretan angka-angka yang dapat dijalankan.
This template, Velli, is great if you have images of visual work that you'd like to form part of your resume, and there's also space for a cover letter.
For Students: Essay in punjabi on internet and academic success!
Computer is very safe tool for data storage which is being used in various fields. Old generations of the computer were less effective with less functions but new generations of it are amazing with high capacity, easy to handle and more functions.
Building capacity in health research in the developing world. The access to the English-speaking reviews is a dominating factor in a scientific community which publishes mainly in English.
A number of explanations are possible.
We should recognize this as a parabola that opens up and has been shifted 2. Completing the Square and Shifting Parabolas getting parabola to vertex form and analyzing the shift of a vertex F-IF.
We may also: Do I need to attend an interview?
Step 4: Atmospheric ammonia and nitric acid also damage respiratory systems. New vs. The best

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======= Instance Index 11115 =========
Input Text: Answer the following question given this paragraph: 

CHAPTER SUMMARY 1.1 Themes and Concepts of Biology Biology is the science of life. All living organisms share several key properties such as order, sensitivity or response to stimuli, reproduction, adaptation, growth and development, regulation, homeostasis, and energy processing. Living things are highly organized following a hierarchy that includes atoms, molecules, organelles, cells, tissues, organs, and organ systems. Organisms, in turn, are grouped as populations, communities, ecosystems, and the biosphere. Evolution is the source of the tremendous biological diversity on Earth today. A diagram called a phylogenetic tree can be used to show evolutionary relationships among organisms. Biology is very broad and includes many branches and sub disciplines. Examples include molecular biology, microbiology, neurobiology, zoology, and botany, among others.


Q: Living things are highly organized following a hierarchy that includes atoms, molecules, organelles, cells, tissues, organs, and organ systems. organisms, in turn, are grouped as populations, communities, ecosystems, and this?

 Choices:

- hydrosphere

- endosphere

- biosphere

- bionicsphere

A:

Target Text: biosphere

#### Retrieved Documents ####

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Retrieved Text: 1.1. An atom is the smallest constituent unit of ordinary matter that has the properties of a chemical element.
1.1.1. the basic unit of a chemical element.
2.1. A group of atoms bonded together, representing the smallest fundamental unit of a chemical compound that can take part in a chemical reaction.
2.1.1. A molecule is an electrically neutral group of two or more atoms held together by chemical bonds.
2.1.2. Molecules are distinguished from ions by their lack of electrical charge.
3.1. A molecule containing a very large number of atoms, such as a protein, nucleic acid, or synthetic polymer.
3.1.2. They are typically composed of thousands of atoms or more.
4.1. Any of a number of organized or specialized structures within a living cell.
4.1.1. Individual organelles are separately enclosed within their own lipid bilayers.
5.1. Cells are the basic building blocks of living things.
5.1.1. Cells provide structure for the body, take in nutrients from food and carry out important functions.
5.1.2. Cells are the basic structures of all living organisms.
6.1. any of the distinct types of material of which animals or plants are made, consisting of specialized cells and their products.
6.1.1. A tissue is an ensemble of similar cells and their extracellular matrix from the same origin that together carry out a specific function.
6.1.2. Organs are then formed by the functional grouping together of multiple tissues.
7.1. Organs are collections of tissues with similar functions.
7.1.1. Organs are composed of main tissue, parenchyma, and "sporadic" tissues, stroma.
7.1.2. Plant and animal life relies on many organs that coexist in organ systems.
8.1. The 11 organ systems of the

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Retrieved Text: Get a quick insight into the different levels of biological organization and the prime aspects related to each one of them, from the following write up.
Our environment is a bag full of components which are different from each other, yet are mutually dependent on each other. The components are both living and non-living and they play vital roles in their own domain. With anyone of the components being absent, the biological organization will suffer in more than one way. In all the levels of this organization, the individual components are responsible for everything which make life possible. It would be unfair to establish a distinction between each of these components, regarding their level of importance. As said, each component holds its own importance in its own place and it is equally dependent on the other components, which again are important to the biological organization.
These particles are smaller than the atom of a substance. Protons, neutrons and electrons are the main subatomic particles which reside in a substance. Protons are positively charged particles and neutrons are charge-less. These reside inside the nucleus of the atom. Electrons are negatively charged particles and revolve around the nucleus in certain energy levels or shells. Photon is also a subatomic particle. A photon is a quantum of electromagnetic energy, that possesses zero mass and rest energy and moves with the speed of light.
Atoms are defined as the smallest unit or the basic building blocks of matter which make up all objects. Atoms are made up of equal number of protons and

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Retrieved Text: The three fundamental propositions of classical cell theory are that the cell is the most basic unit of life, all life is made up of cells and cells are formed only by other cells. Each tenet of this theory is important to understanding the way living things function on every level.
The first proposition, that the cell is the most basic component of living things, can be observed directly. Single-celled organisms are well known and may comprise the bulk of Earth's living biomass. Any unit, such as a tissue, that can be broken down still further cannot be regarded as basic. Units more simple than a cell, however, cannot truly be said to be alive. A cell's organelles, for example, function only in the context of their cellular environment.
From this it follows that all life must be made up of cells. Cells build tissues, tissues make organs, organs are organized into systems and these systems make up the bodies of organisms. Across the domains of life, whether eukaryotic or prokaryotic, all living things can be described in terms of their cells.
Finally, the cell theory posits that the origin of a living cell must be a result of the action of another living cell. Cells do not spontaneously form, and they are too complicated to self-assemble.

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Retrieved Text: With the exception of single-celled organisms and very simple life forms, living things have complex bodies that contain many functional parts. You can organize these parts into different levels of complexity or cellular organization. They range from the smallest, simplest functional units of living things to the largest and most complex.
Most organisms have functional parts with five levels: cells, tissues, organs, organ systems and whole organisms. Cells hold genetic material and absorb outside energy. Tissues make up the bones, nerves and connective fibers of the body. Organs work to perform specific bodily tasks, such as filtering blood. Organ systems are groups of organs that perform a specific kind of function together, such as digesting food. Together, these smaller systems make up an entire living organism, which is capable of growing, using energy and reproducing.
Cells are the smallest functional units of all livings things. Both plants and animals contain various kinds of cells. Cells help living things absorb nutrients. In the case of animals, these nutrients come from food. In the case of plants, they come mostly from sunlight, which plant cells convert into usable nutrients via a process called photosynthesis.
Both plant and animal cells carry genetic material in the form of DNA. Without DNA, livings things would not be able to pass on their individual characteristics or the characteristics of their species to the next generation.
Different kinds of cells perform different functions. For example, in animals, red blood cells help to attack viruses, while sperm and egg cells aid in reproduction.
Tissues are the organic material from

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Retrieved Text: Anatomy describes the form, structure, and location of body parts, while physiology explains their function in important processes and how they relate to each other. Anatomy begins with understanding the building blocks of matter. Sub-atomic particles like protons, neutrons, and electrons form atoms, such as oxygen, carbon, and hydrogen, the most common elements in the human body. Atoms combine to form molecules, which can range from two atoms to several hundred as in macromolecules. Bigger structures include organs, which are composed of tissues made of cells which contain organelles. Organ systems (e.g. respiratory and circulatory), cooperate to form organisms. In anatomy, positions in the body are carefully described according to their relative positions (i.e. anterior vs. posterior); body planes (coronal vs. sagittal and transverse); and quadrants and regions.
Can I use these videos for MCAT preparation?. I would be grateful if you could let me know. I am really struggling to choose as there are so many videos online.
hi, Sir, My internet cannot watch your lessons video .Is there any way else to get it? please help me!
I was wondering if you can recommend a textbook or your personal liking or one that follows your course.
Does membrane belong to organ level of organization ?
I love your lessons very much! and I just pay $300 for it. please let me know how to download your lessons so that I can use it in my iPod.
Your lessons are brilliant! Best biology teacher I have ever had.
hi Bryan, great lectures and a huge thanks for that! Are there any lectures

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Retrieved Text: 1. Indicate whether the following statements are True (T) or False (F).
2. Make a sketch of the human nerve cell. What function do nerve cells perform?
The function of a nerve cell is to transmit messages to the brain and also to take away messages from the brain to the receptor organs.
(a) Cytoplasm: It is a fluid that fills the cell and occurs between the plasma membrane and the nucleus. Cell organelles such as mitochondria, ribosomes, Golgi bodies, etc. are suspended in the cytoplasm. The cytoplasm helps in the exchange of materials between cell organelles.
(b) Nucleus of a cell: Nucleus is the master of the cell. It commands all the functioning of the cell. It is generally located in the center of the cell and is spherical in shape. A membrane called nuclear membrane separates it from cytoplasm. It contains the genetic material DNA and RNA in it. This porous membrane allows the transfer of material in the nucleus and cytoplasm. Nucleus contains a dense body called Nucleolus which actually contains Chromosomes, the genetic material.
4. Which part of the cell contains organelles?
Cytoplasm is the part of the cell that contains various organelles such as mitochondria, ribosomes, Golgi bodies, etc.
5. Make sketches of animal and plant cells. State three differences between them.
They are generally small in size. They are usually larger than animal cells.
Cell wall is absent. Cell wall is present.
Vacuoles are small in size. Vacuoles are larger in size.
No other animal cell possesses plastids except for the protozoan Euglena. Plastids are present.
6. State the difference between eukaryotes

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Retrieved Text: Living Science Solutions for Class 8 Science Chapter 8 Cell Structure And Functions are provided here with simple step-by-step explanations. These solutions for Cell Structure And Functions are extremely popular among class 8 students for Science Cell Structure And Functions Solutions come handy for quickly completing your homework and preparing for exams. All questions and answers from the Living Science Book of class 8 Science Chapter 8 are provided here for you for free. You will also love the ad-free experience on Meritnation’s Living Science Solutions. All Living Science Solutions for class 8 Science are prepared by experts and are 100% accurate.
Which of these is multicellular?
Multicellular means made of more than one cells. Mushroom is a multicellular organism. All the other organisms mentioned here, are unicellular.
The egg of a hen is a cell. It divides repeatedly and differentiates into various tissues to develop into a chicken.
Which of these is not present in an animal cell?
In an animal cell, chloroplasts are not present. Chloroplasts are present in green plants and serve as the sites of photosynthesis in plants.
Which of these is the control centre of the cell?
The control centre of the cell is nucleus. The nucleus contains chromosomes, which divide during cell division.
Which organelles are responsible for energy production in a cell?
Mitochondria is responsible for energy production in a cell.
Which of these is not stated by the cell theory?
(a) Cells are the basic structural units of living organisms.
(b) All cells are identical.
(c) New cells are formed due to division in old cells.
(d) The way an organism functions

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Retrieved Text: Under the influence of ionizing radiation, atoms and molecules of living cells get ionized, which results in complicated physical and chemical processes that affect the nature of human’s further vital activity.
There exists an opinion that ionization of atoms and molecules under the influence of radiation emission leads to breaking bonds in protein molecules, which results in cell death and irradiation of the whole body. However, there is a different opinion that radiolysis products of water, which is known to make up 70% of human body mass, take part in the formation of the biological consequences of ionizing emission. When water is ionized, free radicals H+ and OH- are formed, and, if oxygen is present, peroxide compounds, which are powerful oxidants, are formed as well. The latter enter into a chemical reaction with molecules of protein and enzyme, ruining them, and, as a result, compounds not native to living organisms are formed. This leads to violation of metabolism, oppression of enzyme and certain functioning systems, which means the violation of vital activity of the whole human body.
The peculiarity of ionizing radiation activity is that the intensity of chemical reactions caused by free radicals is growing, and hundreds and thousands of molecules which are not irradiated are involved.
– different organisms have different sensitivity to radiation.
The strongest effect is experienced by the cells of the red bone marrow, thyroid, lungs, and internal organs’ that is the organs with the cells that have a high level of division. The same radiation dose affects more cells in children’s organisms than in

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Retrieved Text: There are many types of tissues in animals, and in plants.
A cell is the smallest unit that can truly be called living.
Most cells are so small that they can only be seen with a microscope.
We can see that inside cells there are smaller parts.
These are called organelles. They are tiny biological machines.
Each organelle has its own job. Examples include the nucleus, ribosome, mitochondria, Golgi, etc.
What is the role of enzymes in cells?
The amazing cell and DNA size and scale app!
Feb 2016 MCAS. Beginning with one parent cell, how many daughter cells are typically produced from one mitotic division?
6.MS-LS1-2. Develop and use a model to describe how parts of cells contribute to the cellular functions of obtaining food, water, and other nutrients from its environment, disposing of wastes, and providing energy for cellular processes.
(unicellular) or many cells (multicellular). Within cells, specialized structures are responsible for specific functions. In multicellular organisms, cells work together to form tissues and organs that are specialized for particular body functions.
Grades 9-10: Systems of specialized cells within organisms carry out essential functions of life. Any one system in an organism is made up of numerous parts. Feedback mechanisms maintain an organism’s internal conditions within certain limits and mediate behaviors.

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Retrieved Text: Key concept - Relations - What are the links between microorganisms and our health?
Related concepts - Function, Balance and Consequences - Does investigation and understanding of the interaction between ourselves and pathogens help us achieve equilibrium in our physical well-being?
Global context - Globalization and Sustainability - Which are the reasons for the differences in health between different countries? Would it be possible for everyone to have access to proper health care?
Health is a complete state of physical, mental and social well-being, and not merely the absence of disease or infirmity.
The tasks and questions on the Weebly will be coloured to represent the different style of questions that you will find in your exams. The task should be completed in your "Natural Sciences" GoogleDrive document.
There will also be "extension" tasks for students who finish tasks quickly! Also look out for links to interactive resources and videos.
The cell is the basic structural, functional and biological unit of all living things. For this reason, it is considered the smallest collection of matter that can be classed as alive; a cell is the smallest form of life.
Prokaryotic cells are simple cells that do not have a true nucleus. They have simple organelles, but lack membranous organelles, and they have a cell wall.
Eukaryotic cells are those which do have a true nucleus. They are larger than prokaryotes, do not always have a cell wall, and have organelles which perform specialised functions.
a) Insert a table and use it to compare and contrast prokaryotic and eukaryotic cells.
b) Explain why a cell from our

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Retrieved Text: Karl August Möbius was the German zoologist who took the credit for the usage of a diminutive or organ. Organula was the tern used by this zoologist for the cellular structure.
The term organelle is considered similar with the cell compartment based on the opinion of most cell biologists.
The cell biologists who choose the specific definition of cell organelles state that a term can only be applied on those which contain DNA.
The organelles which contain DNA include plastids which can be found on some protists, algae and plants. Almost all eukaryotes contain mitochondria.
There are several organisms which have the organelles without DNA. It can be found on the flagellum.
The structure of Eukaryotic cells is very complex. The lipid membranes enclose the interior compartments of the cells.
You can use the light microscope to scrutinize the large organelles on the eukaryotic cells. You will be able to observe the vacuoles and nucleus. Mitochondria are considered as the common organelle that can be found in most eukaryotic cells.
If you compare the Eukaryotic cells and prokaryotic cells, the latter ones are less complex. In the past, people believe that the internal organization of the prokaryotic cells was little. Find facts about cell wall here.
It is stated that some prokaryotes have the micro compartments based on the current research about this cell. The diameter of the compartment is around 100–200 nm. The shell of protein is seen as the enclosure of this sub cellular compartment. Get facts about cell membrane here.
Based on the report in 2006, bacteria have the membrane-bound magnetosomes. In

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Retrieved Text: The diagram below needs explanation, but it won’t be easy, because the ecosystem is so complicated that it is impossible humanly to represent or to fully understand.
If you find it mind boggling to comprehend the levels of organization, all interacting among and between themselves, then you are just like the scientists, the politicians, the religious and everyone else. Fortunately, we do not need to understand all the little details of the system in order to have a good idea of how it functions — the structural and functional requirements for it to stay alive — and that is our goal. A basic appreciation of the beautiful idea of networking. and of the levels of organization. is background for understanding the flow of energy, and of other things, through the living ecosystem. Life is possible because of the internet of living and nonliving things through all the levels. The basic format of these realities is outlined in the below diagram.
We are only one component of the metabolism of the ecosystem. Our lungs breathe the oxygen that is provided by plants; our food gives us the energy we require for life; the environment degrades our wastes, so that we are not suffocated in a dung-heap of the unused byproducts of our metabolism. These processes are carried out by other organism that all are interacting within all the big and little ecosystems of life on earth. We could not survive without the other elements of the ecosystem, and we also contribute to the other elements of the ecosystem.
1-The whole

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Retrieved Text: All living organisms on Earth are divided into cells. The main concept of cell theory is that cells are the basic structural unit for all organisms. Cells are small compartments that hold the biological equipment necessary to keep an organism alive and successful. Living things may be single-celled or they may be very complex such as a human being.
There are smaller pieces that make up cells such as macromolecules and organelles. A protein is an example of a macromolecule while a mitochondrion is an example of an organelle. Cells can also connect to form larger structures. They might group together to form the tissues of the stomach and eventually the entire digestive system. However, in the same way that atoms are the basic unit when you study matter, cells are the basic unit for biology and organisms.
In larger organisms, the main purpose of a cell is to organize. Cells hold a variety of pieces and each cell type has a different purpose. By dividing responsibilities among different groups of cells, it is easier for an organism to survive and grow.
If you were only made of one cell, you would be very limited. You don't find single cells that are as large as a cow. Cells have problems functioning when they get too big. Also, if you were only one cell you couldn't have a nervous system, no muscles for movement, and using the internet would be out of the question. The trillions of cells in your body make your way of life possible.
There are many types

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Retrieved Text: Organisms that are unicellular and lack a membrane bound nucleus are called _____.
Organisms that are unicellular or multicellular and have a membrane bound nucleus are called ______.
These organisms are found almost everywhere including the air and soil as well as your digestive tract.
Biology is the study of _____.
Which of the following is generally tested by experimentation?
Which two of these are typically use to test a hypothesis?
A representation of an actual subject that can be studied firsthand and that aids in our understanding of a process is called a(n) ______.
Which group in an experiment, is a test group that isn't exposed to the experimental variable?
The results of an experiment are referred to as _______.
In science, a concept that is supported by a broad range of observations, experiments, and data is called a scientific ______.
Also known as the independent variable, the factor in an experiment that is being tested is called the experimental _____.
The manner in which a scientist intends to conduct an experiment.
Two statements that best describe the responding (dependent) variable.
It is due to the experimental treatment.
It is called the dependent variable.
It is held constant throughout the experiment.
It is the factor that is being tested.
It is due to the experimental treatment. AND It is called the dependent variable.
The basic building block of life, and the biological level in which the properties of life are first observed is the _____.
The hereditary information for an organism is held by _____ molecules.
The capacity to do work is called ______.
Which of the following is a characteristic of all living organisms?
Unicellular organisms

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Retrieved Text: Research Journal of Biology [ISSN: 2322-0066] is an International, fully open accessed, peer-reviewed, medical biology journal that is purely dedicated to collect and disseminates basic and applied research knowledge belonging to almost all area of biological research work across globe. The research work may belong to Plant, Animal, Microbial, Medical Science and other Interdisciplinary Sciences.
Research Journal of Biology encourage and motivate researchers to submit their research manuscripts in various competing areas of Biology viz., Human Physiology and Medical Biology, Biotechnology, Agriculture, Microbiology, Biochemistry, Plant Biology, Animal Biology, Genetics and Molecular Biology, Pharmacy & Pharmacology, Entomology and Toxicological Sciences, Fisheries, Food Science & Nutrition, Bioinformatics, Bioengineering, Marine Biology, medical biology, Environmental Sciences & Ecology, Bioethics, Biomedical Engineering and many more branches in the field of biological Science and Technology for publication of their significant research work in order to validate their work and prepare a path for upcoming researchers in the same field.
Research Journal of Biology is a leading journal of biosciences and medical biology which includes research paper from all available domain under biological research and facilitates fast and accurately validated research publication in india. A wide variety of researcher community can take benefit with this great platform in regards of research work validation and fast and effective exposure of research to world researchers community.
Research Journal of Biology welcomes full "Original Research Papers", “Research Article (Short)”, as well as “Review Articles”. All the accepted papers will be published in English language only. The primary criteria for publication are originality of research, scientific quality and biological significance

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Retrieved Text: The organic deterioration experienced by people with the passage of time is mainly due to the damage caused by free radicals on cellular tissues. These free radicals are highly reactive molecules, which over time, with cumulative effects, can damage tissues and organs, affecting their functions. This damage is known as oxidative stress or cellular oxidation and is the main responsible aging and age-associated diseases.
The production of free radicals in the cells increases as the person to have more exposure to environmental and industrial contaminants such as smoke, pesticides, chemicals, fatty foods, sunlight, cigarette smoke, alcohol, stress, etc. And therefore the aging and deterioration of the body depends on the lifestyle of people. For this reason the average life span of people is shorter in poor countries, high pollution, and less healthy habits.
The deterioration of the organs that are affected from free radicals is not always uniform, but some organs that carried hereditary conditions, trauma or infectious and degenerative diseases, deteriorates more than others. For these cases Biocell Ultravital, offers a set of restorative therapies, which benefit specific organs or the whole body.
Therapies Cellular Renewal of Biocell act directly on the cells, inducing through its embryonic tissues and cleaning the accumulated biological material natural enzymes, promoting “Autophagy " by which the cell digests the waste material, which a once reduced to its basic elements, is reused to make new proteins, enzymes, lipids, etc. Thus, cells devoid of biological material accumulated, can gradually recover its functionality supported by the various components of the therapy.
The embryonic tissues, coenzymes and

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Retrieved Text: As atomic radiation permeates living tissues, highly-organized units of living matter in the cell are disrupted. Fundamentally, the cell is composed of atoms and molecules which are split by radiation into electrically-charged fragments. This ionization process is completed in less than a trillionth of a second, yet it triggers off a chain reaction of subtle events within the cell leading to its damage or eventual death. Since cells are not inert blobs of matter but living, reproducing, organisms, they react to the radiation-induced injury by repair processes which lead to apparent recovery. If the radiation dose is overwhelming, immediate or only slightly delayed death of the cell ensues when the cell attempts to divide.
A single dose of 50 r to the whole body causes the number of lymphocytes to drop by one-half in about “two to three days. It takes about a week for it to return to the preradiation level. After higher but nonlethal doses of radiation, the lymphocyte drop is abrupt and little or no evidence of recovery may be apparent for several months. In fact, it may take years before the number of white cells returns to normal. Another significant observation is the fact that individuals previously exposed to radiation show a greater depression of cell numbers upon subsequent radiation exposure.
days. These effects were confirmed in another experiment involving 120 persons.
There have also been several reports of brain damage in persons given heavy doses of radiation for brain tumors or for scalp lesions.

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Retrieved Text: Cellular biophysics analyses life processes at the level of organelles and whole cells.
Cellular biophysics is a branch of biophysics that focuses on the physical principles of cell function. It performs a bridging function from the atomic or molecular understanding of proteins, membranes and polynucleotides to the highly complex and highly integrated systems of organelles and whole cells. Finally, the investigation of tissues and organs ties in with medical biophysics.
Current areas of cellular biophysics are intracellular signal dynamics and transport, cell mechanics, molecular motors and electrophysiology. The field has benefited greatly from recent advances in the imaging of living cells that allow spatial and temporal measurement of macromolecules and their function. The control of cellular processes by light (optogenetics) also provides unique possibilities for the investigation of physiological processes. The combination of novel experimental tools with mathematical models is a particular strength of this area.
Section III of the DGfB provides a platform for discussion and collaboration in the field of cellular biophysics. The biennial section conference, which attracts international biophysicists and researchers from related disciplines, is particularly suitable for this purpose. The next section workshop entitled "The workings of ion transporters and channels" will take place from August 9-11, 2019 in Berlin-Wannsee.

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Retrieved Text: Regenerative medicine is the process of creating living, functional tissues to repair or replace tissue or organ function lost due to age, disease, damage or congenital defects. It includes the injection of stem cells or progenitor cells (also known as cell-based therapies), the induction of regeneration by biologically active molecules, and transplantation of in vitro grown organs and tissues. The core mission of the Center of Regenerative Medicine and Cell-Based Therapies (CRMCBT) is to productively engage related expertise in the local community, both inside as well outside Ohio State and to deliver innovative health care solutions through multidisciplinary partnerships. CRMCBT is committed to developing core as well as shared resources that may be leveraged by investigators throughout the campus to develop research on regenerative medicine and cell-based therapies.

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Retrieved Text: A prokaryotic cell does not contain any true nucleus. This is why it is called a cell with a primitive type of nucleus. The term nucleotide fits nice in this case. Nuclear materials in a prokaryotic cell are not surrounded by any nuclear membrane. They are dispersed in its cytoplasm. Though the cell organelles such as mitochondria, plastids, endoplasmic reticule etc. are not found in a prokaryotic cell, ribosomes are present in it. Only the unwrapped DNA constitutes the chromosomal structure of a prokaryotic cell. For example, blue, green algae and bacteria are constituted of this type of cell.
In this type of cell, the nucleus is well structured that means nuclear materials are well organised and surrounded by a nuclear membrane. Chromosomes are organised with DNA, histone protein, and other components. From algae to higher flowering plants and from Amoeba to advanced animals, the basic structural and functional component is eukaryotic type of cell. Along with ribosome, other cell organelles are present in the cell.
On the basis of function, there are two other types of cells: somatic cell and gametic cell.
This type of cell takes part in the organization of the body of an organism. The cell divides through the process of binary fission and mitotic division. Organisms grow in this way. Moreover, cells take part in the organization of different organs and organ systems.
Gametal cells are produced in the organisms in which sexual reproduction and alternation of generations occur. Primordial germ cells divide through meiotic division and produce gametic cells. In a gametic cell, a

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Retrieved Text: Biology is the subject which deals with study of all life forms existing on the Earth. It comprises of Bo tony (Study of plants) and Zoology (Animals). On the other hand, Chemistry is the subject which deals with chemicals in terms of the interaction occurring between them, how a new molecules or compound are formed based upon such interaction.
When these two subjects are studied together it is biochemistry. In nutshell biochemistry is biological chemistry. It is laboratory based science that ties up biology and chemistry.
Biochemistry is concerned with the molecules that make up the structure of cells and organs that is molecular anatomy. It deals with the carbon compounds and the reactions they undergo in living organisms. It is also concerned with molecular physiology; that is, the functions of molecules in carrying out the needs of the cells and organs.
It emphasis on the mechanism happening inside cells, studying components like proteins, lipids and organelles, how cells communicate with each other.
Carl Alexander Neuberg was an early discoverer in biochemistry, and called as the "Father of Biochemistry". We all are aware of the fact that human body is made up of different types of organ system. Organs are nothing but a group of tissues. The tissues are the group of cells. For the formation of cell into an organ it needs lots of metabolic activities and macro and micro molecule substances. Mainly these substances include- Carbohydrates, Proteins, Fats and Lipids. Among these glucose plays a vital role as it is the major source of energy. Plant in the

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Retrieved Text: Zooming in on the cell-- what makes animals and plants different?
Zooming in on the cell– what makes animals and plants different?
Plants and animals are about as different as you can get. Plants make their own food and are stuck in one place, while animals need to find food to eat and can move around on their own. But, what makes plants and animals truly different? Each living organism is built from cells, and though plant and animal cells are very similar, there are key differences between these organisms.
What makes the deer and ferns different? Image credits: Max Pixel.
As a small high school biology recap, all cells, regardless of whether they are in plants or animals, are bound in a membrane and contain organelles that perform tasks that keep the cell going. The core organelles in plant and animal cells are responsible for essential tasks such as processing energy, making new proteins, and getting rid of waste as performed by the mitochondria, endoplasmic reticulum, the Golgi Apparatus, and others. The activities going on in these cells are coordinated by the nucleus, which also stores precious DNA. Now, on to what make plant and animal cells special.
Plants have three main differences that distinguish them from animals. Chloroplasts allow plant to make their own food by harnessing the energy of the sun. A really long time ago (millions of years), single celled organisms evolved the ability to use solar energy to split water molecules and generate oxygen. Cells engulfed some of these photosynthetic organisms, and likely formed a symbiotic

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Retrieved Text: Living tissues are ultimately made of chemical building blocks. Thus, in the study of anatomy and physiology, some understanding of chemistry is necessary.
Chemistry deals with the study of the composition, structure, properties and change of matter. It deals with the properties of atoms, how atoms form chemical bonds to create chemical compounds, interactions of substances through intermolecular forces that give matter its general properties, and the interactions between substances through chemical reactions to form different substances.
Biochemistry is the study of chemical processes within and relating to living organisms. It deals with the structures, functions and interactions of biological macromolecules such as proteins, nucleic acids, carbohydrates and lipids. These molecules form the structure of cells and perform many of the functions associated with life.

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Retrieved Text: According to cell theory, living organisms are composed of cells.
Organisms consisting of only one cell carry out all functions of life in that cell. e.g. Paramecium, Chlorella.
Surface area to volume ratio is important in the limitation of cell size.
Specialised tissues can develop by cell differentiation in multicellular organisms.
Differentiation involves the expression of some genes and not others in a cell.
Stem cells can divide and differentiate along different pathways in embryonic development which makes stem cells useful for therapeutic uses (e.g. Stargart's disease).
There are ethical concerns about the use of embryo stem cells.
The compartmentalised structure of Eukaryotic cells.
The resolving power of electron microscopes is between 10µm and 1nm whereas light microscopes resolve details between 1mm and 1µm.
Explain how the composition of organelles will be different in cells with different functions, e.g. exocrine gland cells (eg. goblet cells which make mucus and palisade mesophyll cells which do photosynthesis).
Application: explain how the structure of prokaryotes allows them to divide by binary fission.
Know how the structure helps the function of sodium–potassium pumps for active transport and potassium channels for facilitated diffusion in axons.
Understand why tissues (or organs) waiting to be used in medical procedures must be bathed in a solution with the same osmolarity as the cytoplasm to prevent osmosis.
Draw a diagram of the fluid mosaic model.
Explain how evidence from electron microscopy led to the proposal of the Davson-Danielli model.
Outline the evidence which led to the falsification of the Davson-Danielli model and support of the Singer-Nicolson model.
Can you draw a diagram of the fluid mosaic model.
Can you explain how evidence

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Retrieved Text: SSC Biology Board Question Dhaka Board 2016. Biology is a natural science concerned with the study of life and living organisms, including their structure, function, growth, evolution, distribution, and taxonomy. Modern biology is a vast and eclectic field, composed of many branches and subdisciplines. However, despite the broad scope of biology, there are certain general and unifying concepts within it which govern all study and research, consolidating it into the single, coherent field. Biology generally recognizes the cell as the basic unit of life, genes as the basic unit of heredity, and evolution as the engine that propels the synthesis and creation of new species. It is also understood today that all organisms survive by consuming and transforming energy and by regulating their internal environment to maintain a stable and vital condition.
Subdisciplines of biology are defined by the scale at which organisms are studied, the kinds of organisms studied, and the methods used to study them: biochemistry examines the rudimentary chemistry of life; molecular biology studies the complex interactions among biological molecules; botany studies the biology of plants; cellular biology examines the basic building block of all life, the cell; physiology examines the physical and chemical functions of tissues, organs, and organ systems of an organism; evolutionary biology examines the processes that produced the diversity of life; and ecology examines how organisms interact in their environment.

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Retrieved Text: the kingdom on the other side.
Foldable. Label it as shown.
sugars form a netlike structure that is porous and strong.
Copyright © McGraw-Hill Education. Permission is granted to reproduce for classroom use.
on cell type, structure, and nutrition.
more abundant than any other organism.
that do not have a nucleus or other membrane-bound organelles.
What are the characteristics of archaea?
of marshes. Little or no oxygen is found in these environments.
waters. The water temperatures can reach 98˚C, almost boiling.
What are the characteristics of Kingdom Protista?
protists, animal-like protists, and funguslike protists.
plantlike protists because they perform photosynthesis.
What are the characteristics of Kingdom Fungi?
4. Define What are hyphae?
chitin, which is a rigid polymer that gives cells structural support.
70,000 species of fungi have been identified.
the nutrients directly into their cells.
food from algae that live among the fungi’s hyphae.
What are the characteristics of Kingdom Plantae?
Members of Kingdom Plantae (PLAN tuh) are called plants.
Plantae. Plants form the base of all land habitats.
plant. It obtains food through suckers connected to the host plant.
vascular plants have organs such as roots, stems, and leaves.
What are the characteristics of Kingdom Animalia?
organisms and have membrane-bound organelles.
organized into organs such as skin, a stomach, and a brain.
such as digestive, circulatory, and nervous systems.
Animals range in size from a few millimeters to many meters.
Is there an exception to the classification system?
not usually placed in the biological classification system.
on a variety of factors.
table, think of organisms that fit into each kingdom.

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Retrieved Text: Cell biology is the branch of life sciences which deals with the physiology and functional biology of the cells. cells are the basic unit of life which collects in a large number to form an organ, organ system and subsequently a living organism. In this branch, a student is required to study the organelles they contain, interactions with their environment, their life cycle, division, and death. This is done both on a microscopic and molecular level. Cell Biology Assignment Help research encompasses both the great diversity of single-celled organisms like bacteria and protozoa, as well as the many specialized cells in multicellular organisms such as humans.
Appreciating the similarities and differences between cell types is particularly important to the fields of cell and molecular biology as well as to biomedical fields such as cancer research and developmental biology. These fundamental similarities and differences provide a unifying theme, sometimes allowing the principles learned from studying one cell type to be extrapolated and generalized to other cell types. Therefore studies in cell biology is closely related to genetics, biochemistry, molecular biology, immunology, and developmental biology. Within cells there is an intricate network of organelles that all have unique functions. These organelles allow the cell to function properly. Arranged below according to location (nucleus, cytoplasm, and surface) is a description of common organelles. This subject of life sciences is highly complicated and requires undying attention of a student. it is very important that a student have sufficient time to understand the concepts of subjects and have a developed skill set

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Retrieved Text: Mitochondria are essential components of nearly all cells in the body. These organelles are the powerhouses for cells, providing energy to carry out biochemical reactions and other cellular processes. Mitochondria make energy for cells from the chemical energy stored in the food we eat.
Mitochondria are found in all body cells, with the exception of a few. There are usually multiple mitochondria found in one cell, depending upon the function of that type of cell. Mitochondria are located in the cytoplasm of cells along with other organelles of the cell.
How did mitochondria come about?
This question has been raised due to many characteristics shared by mitochondria and other single cellular living organisms. For example, mitochondria are the only organelles in the cell which contain their own DNA, as well as their own protein making machinery. Researched has shed light on the possibility of a theory known as endosymbiosis.
When life first began on our planet, single celled organisms produced energy in a way that was highly inefficient (anaerobic respiration, meaning without oxygen) compared to what most multi-cellular organisms use today (aerobic respiration, using oxygen). Through evolutionary time, plants came about and were able to produce oxygen in the atmosphere giving rise to aerobic respiration which produced energy in a highly efficient manner. The theory of endosymbiosis suggests that mitochondria were once free living organisms on their own that used aerobic respiration. Larger anaerobic cells simply engulfed these aerobic mitochondria to use their energy, giving rise to complex cells we find today such as those in our bodies.
Our food contains

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Retrieved Text: Mitochondria were isolated from lymphoblasts derived from normal (squares) or TRMA individuals (circles) were incubated for 15 minutes with various concentrations of radioactive thiamine.
Mitochondria were isolated from normal (open squares) or TRMA (open circles) lymphoblasts and were incubated for 15 minutes with various concentrations of radioactive ThDP.
Uptake of thiamine and ThDP by mitochondria was determined by a rapid filtration procedure [26,28].
Mitochondria are membrane-enclosed organelles distributed through the cytosol of most eukaryotic cells.
This has strengthened the theory that mitochondria are the evolutionary descendants of a bacterium that established an endosymbiotic relationship with the ancestors of eukaryotic cells early in the history of life on earth.
Perhaps rickettsias are the closest living descendants of the endosymbionts that became the mitochondria of eukaryotes.
Mitochondria are responsible for converting nutrients into the energy-yielding molecule adenosine triphosphate (ATP) to fuel the cell's activities.
This function, known as aerobic respiration, is the reason mitochondria are frequently referred to as the powerhouse of the cell.
Mitochondria are unusual organelles in that they contain deoxyribonucleic acid (DNA), typically found in the cell’s nucleus, and ribosomes, protein-producing organelles abundant in the cytoplasm.
Mitochondria are able to modify their structure to meet the changing requirements of the cell.
Mitochondria may fuse or increase in size to form giant mitochondria or megamitochondria, and they are also able to divide in a sequence that morphologically resembles bacterial division.
Mitochondria tend to locate near the structures were the energy is required, as illustrated by the close association with rough endoplasmic reticulum in cells with high synthetic activity.
Mitochondria are sometimes described as "cellular power plants", because their

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Retrieved Text: Confusion may sometimes surround terms used in the fields of generics and biosimilars. This has been recognised as a problem by EMA, who has expressed the need to propose a more precise definition for biosimilars due to problems arising from imprecise usage of the terms in the scientific literature and elsewhere.
The source of some of this confusion is due to authorities in various regions of the world defining terms differently and other instances are due to a misunderstanding of the actual nature, characteristics, and method of research and manufacture of these biological products.
In an attempt to prevent any such confusion for GaBI Online readers, here is a glossary of the relevant terms for biosimilars and generics as used in GaBI Online.
Active ingredient or molecule that goes into a specific medicine and provides this medicine with properties for treating or preventing one or several specific disease(s).
The occurrence of an undesirable, unpleasant or life-threatening reaction to a medicinal product.
A response to a medicinal product, which is noxious and unintended.
Building blocks of proteins. There are 20 common amino acids found in proteins.
A condition that is due to a reduced number of red blood cells or reduced amounts of haemoglobin within them. This results in reduced oxygen-carrying capacity and reduced aerobic activity in blood cells. The symptoms include marked tiredness. Anaemia often occurs after chemotherapy.
An acute and severe allergic reaction in humans.
Antibodies (also known as immunoglobulins, abbreviated to Ig) are proteins found in blood or other bodily fluids. They are produced by humans and animals in response to the presence

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Input Text: Answer the following question given this paragraph: 

Figure 34.16 Digestion of carbohydrates is performed by several enzymes. Starch and glycogen are broken down into glucose by amylase and maltase. Sucrose (table sugar) and lactose (milk sugar) are broken down by sucrase and lactase, respectively.


Q: Digestion of carbohydrates is performed by several enzymes. starch and glycogen are broken down into glucose by amylase and maltase. sucrose (table sugar) and lactose (milk sugar) are broken down by sucrase and this?

 Choices:

- lipase

- lactase

- pepsin

- hydrolase

A:

Target Text: lactase

#### Retrieved Documents ####

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Retrieved Text: 1. Ingestion - Taking in food into the buccal cavity through mouth.
2. Deglutition - The passage of food bolus from oral cavity to stomach. This is also called swallowing.
3. Digestion- Since the organic constituents of the food are large and cannot diffuse through the gut wall to enter the blood stream. Hence these constituents have to be broken down to simpler forms.
Mechanical -this includes physical breaking of solid pieces, churning of food and movement of food along the digestive tract.
Chemical- this includes hydrolysis of food macromolecules with the aid of enzymes present in the digestive juices.
4. Absorption- The process by which the digested nutrient molecules are taken into the cells of a living organism.
5. Assimilation- The process by which the absorbed nutrients are incorporated into the cells/tissues..
6. Egestion- The elimination of the undigested food. The process is called defaecation.
The food we eat contains carbohydrates, fats and proteins which are broken down to simpler molecules for absorption.
Carbohydrates in the food are in the form polysaccharides (starch, glycogen and cellulose) oligosaccharides (dextrin) and disaccharides (sucrose and lactose).
These carbohydrates are broken down by carbohydrases to monosaccharides that can be absorbed easily.
The carbohydrate digestion begins in the buccal cavity and is completed in the small intestine.
Food remains in the buccal cavity for a very short time, hence only 30% of digestion takes place here.
Mastication breaks the food into small pieces hence, facilitates the action of salivary amylase.
The gastric juice in the stomach does not contain any carbohydrate digesting enzymes.
The HCl present here also destroys ptylain.
Hence there is no carbohydrate digestion

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Rank: 1
Score: 84.65903
Retrieved Text: Which pancreatic cells secrete insulin?
Which pancreatic cells secrete glucagen?
What is the role of insulin? And how does it function?
What is the role of glucagen? And how does it function?
What happens when a mammal lives in a particularly cold environment for several weeks?
Why leptin treatments were not successful in controlling obesity?
Breaking down of macromolecules from food into monomers for absorption and assimilation.
Secretion of pancreatic juice into the lumen of small intestine.
The circular (inside) and longitudinal muscle layers in the wall exert continuous moderate force, leading to waves of vigorous contractions along the alimentary canal.
Circulary M behind the bolus contract, restricting the gut to prevent the bolus from being pushed back --> longitudinal M at where the bolus is located also contracts, moving the bolus along the gut.
M contractions controlled unconsciously by the enteric nervous system.
Slow to allow maximum digestion and absorption: mixing with enzymes, diffusion etc.
Why do the epithelium cells of the small intestine has immobolized enzymes attached to it?
Therefore, these macromolecules need to be broken down further by enyzmes secreted by gland cells in the intestine wall in intestinal juice.
Absorbed monomers from digestion, mineral ions, and vitamins.
Hydrolysis of starch is catalyzed by pancreatic amylase and maltase, glucosidase and dextrinase found in intestinal epithelium cells.
Amylase breaks 1-4 bonds in amylose and amylopectin. 1-6 bonds cannot be broken down by amylase --> enzyme-substrate specifity.
Sodium-potassium pumps on the in-ward facing membrane of epithelium cells generate low Na concentration by pumping 3 Na ions out to interstitial space and 2 K in per time.
Na-glucose co-transporter transfer a Na and a

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Rank: 2
Score: 75.29933
Retrieved Text: WHICH ENZYMES DO WE REQUIRE FOR DIGESTION?
Every enzyme is responsible for digesting a specific substance. If we are deficient in any particular enzyme needed for the digestion process then the particles not digested fully will render a list of side effects that most of us are too familiar with. This lack of proper digestion may also lead to health issues and sometimes serious illness. Depending on the types of enzymes we are depleted in will usually determine the side effects link to them. It is vital that we consume the correct types and amounts of digestive enzymes to breakdown the all the food groups that we consume.
Lactase – Lactase is essential for digestive hydrolysis of lactose in milk. Deficiency of the enzyme causes lactose intolerance. Lactose intolerance is an inability to digest and absorb lactose (the sugar in milk) that results in gastrointestinal symptoms when milk or products containing milk are drunk or eaten. Lactose is a larger sugar that is made up of two smaller sugars, glucose and galactose. In order for lactose to be absorbed from the intestine and into the body, it must first be split into glucose and galactose. The glucose and galactose then are absorbed by the cells lining the small intestine. The enzyme that splits lactose into glucose and galactose is called lactase, and it is located on the surface of the cells that line the small intestine.
Bromelain – An enzyme that is derived from pineapple, this nutrient also facilitates the digestion of proteins. Bromelain has also been associated with

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Rank: 3
Score: 75.11736
Retrieved Text: The term sugar is the generic term for any disaccharides and monosaccharides. Sugars are an essential structural component of living cells and a source of energy in many organisms. Sugars are classified based on the number of monomeric units present. The term simple sugars denote to the monosaccharides. The term table sugar or granulated sugar actually refers to sucrose, which is a disaccharide made of two monosaccharides: glucose and fructose. Sucrose is the form of sugar that many people are familiar with. It is used in food preparation, such as in cakes, pastries, and desserts. It is also used as an ingredient in several beverages, such as sodas, coffee, and juices.
Carbohydrates, especially polysaccharides, are one of the four major groups of biomolecules. The others are proteins, amino acids, and nucleic acids. A carbohydrate refers to any of the group of organic compounds consisting of carbon, hydrogen, and oxygen, usually in the ratio of 1:2:1, hence the general formula: Cn (H2O) n. Carbohydrates are the most abundant among the major classes of biomolecules. They are one of the major nutrients, providing energy that shall fuel various metabolic processes.
As a nutrient, carbohydrates may be classified based on their structural complexity: simple and complex. Simple carbohydrates, sometimes referred to as simply sugar, are those that are readily digested and serve as a rapid source of energy. Complex carbohydrates (such as cellulose, starch, and glycogen) are those that need more time to be digested and metabolized. They often are high in fiber and unlike simple carbohydrates they are less likely

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Rank: 4
Score: 74.083176
Retrieved Text: Simple carbs, being sugars (glucose), are absorbed into the bloodstream very quickly. The exception is fruit sugar (fructose) which needs to be converted into glucose first.
Complex carbs (especially low glycemic index complex carbs) many of which are starchy carbohydrates, need more time to be digested.
The process begins in the mouth when an enzyme in saliva (amylase) begins to break down starchy carbohydrates.
After swallowing, the starchy carbs reach the stomach where hydrochloric acid combines with them and acts on the protein in the food. The stomach also acts as a reservoir for food, squirting out small amounts into the intestines at intervals.
In the small intestine (where most carb-digestion occurs) the starch is processed by the enzyme amylase and converted into maltose and sucrose.
The maltose and sucrose are then absorbed into the lining cells of the intestine and are further simplified, being converted into glucose.
Once the starchy or sugary carbs are digested and converted to glucose, the glucose then enters the bloodstream and the level of blood-glucose rises. This induces the pancreas to secrete insulin into the blood which "mops up" the glucose and helps convert it into the storage-type of carbohydrate, called glycogen, which is deposited in the liver and in the muscles.
When the liver and muscle glycogen stores are full, any extra glucose is converted into fat. This adds to fat stores, but to a lesser extent than fat released from fatty foods.
The liver glycogen helps to keep blood-sugar levels in the normal range. If blood sugar falls, glycogen is converted into glucose which enters the

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Rank: 5
Score: 71.304085
Retrieved Text: GutZyme™ is a digestive supplement is perfect for people who have adequate HCL levels but want to maximize their absorption of fats, proteins, minerals and other nutrients.
This high-potency, multi-enzyme formulation offers an unusually complete range of plant/microbial-based enzymes that work in concert to help maintain normal enzyme levels that support the body’s digestive capabilities and assist intestinal repair mechanisms. The broad-spectrum combination of enzymes in GutZyme™ maximizes the breakdown, absorption, and utilization of macronutrients from the widest spectrum of foods, including proteins and protein peptides, carbohydrates, lipids and fats. As such, GutZyme™ can serve as an important dietary adjunct for individuals requiring maximal nutrient uptake and for those with compromised gastrointestinal function such as maldigestion, malabsorption, dysbiosis, or intestinal inflammation.
You can even open up the capsules to consume since it does not contain HCL and Pepsin.
Glucoamylase helps to break down starch that occurs naturally in most vegetables.
Invertase is a carbohydrate-digesting enzyme that splits sucrose (common table sugar) into its component parts, glucose and fructose.
Maltase breaks down the disaccharide maltose in to two glucose molecules, which are easily oxidized by the body for energy.
Alpha-Galactosidase helps break down the polysaccharides and oligosaccharides found in foods that are typically more-challenging to digest such as peanuts, beans, lentils and cruciferous vegetables, such as cauliflower, cabbage, broccoli and Brussels sprouts.
Beta-Glucanase represents a group of carbohydrate enzymes which break down glycosidic bonds within beta-glucan.
Three different types of Lipase to maximize the absorption of healthy fats and oils.
Phytase to boost mineral bioavailability and absorption.
Protease to assist in the proper digestion of protein.
Amylase to

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Score: 69.48591
Retrieved Text: YOU CAN CLICK ON THE SLIDE SHOW BELOW TO PAUSE, PLAY, OR NAVIGATE BACK AND FORTH!
AMYLASE is an enzyme that is found in our bodies that functions to help the body in the digestion food. Amylase is found in saliva and in the pancreas. Amylase catalyzes the hydrolysis (breaking down) of starch, glycogen and related polysaccharides into more simple and readily usable forms of sugar.
​In this lab you will explore the effects of concentration, pH and temperature on amylase's ability to break down starch into sugar.
AMYLASE has an OPTIMAL RANGE of pH and Temperature which is pH = 7 (neutral) and 37 degrees C. These are the same conditions that exist in our bodies. When an enzyme is within its Optimal Range or conditions, it will be able to catalyze reactions at its fastest rate.
Enzymes are not products or reactants in the chemical reaction, they just assist (catalyze) the reaction by making it proceed much more quickly than it would in the absence of the enzyme. For this reason, amylase can be used again and again! Enzymes are a special class of proteins. In the absence of the enzyme, the chemical reactions of digestion would occur at such a slow rate, the body would essentially starve to death. The digestive system would take about 50 years to process just one meal, if it did not have the needed enzymes to speed up the process.

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Rank: 7
Score: 68.78571
Retrieved Text: Digestion is a fine-tuned, complicated process that allows you to utilize nutrients from the food you eat. Several organs and accessory organs release enzymes that aid in the digestive process. When you eat a meal rich in all of the macronutrients -- carbohydrates, proteins and fats – the digestive enzymes work together to break down the nutrients into particles that are small enough for your body to absorb.
Amylase helps turn carbohydrates into simple sugars, like glucose, that your body can absorb. The enzyme is produced in two places in your digestive tract -- your mouth, via your salivary glands, and your pancreas. The salivary glands release amylase, along with mucus, electrolytes and water, in the form of saliva when food enters your mouth. The amylase in saliva begins the breakdown of starches. When the digested material reaches your duodenum -- the first section of your small intestine -- the pancreas releases amylase to finish the breakdown of carbohydrates so that your small intestine can absorb the sugars.
Lipase breaks the fat you eat down into smaller molecules that can pass through your small intestine and into your blood. Your mouth and stomach produce some lipase, but the largest volume is produced by the pancreas. Most people produce enough lipase to adequately break down the fats they eat, but those with celiac disease, cystic fibrosis and Crohn’s disease may be lacking in the enzyme.
Protein digestion begins in the stomach, but the bulk of digestion occurs in the small intestine where proteases from your pancreas are released. There are

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Rank: 8
Score: 67.017456
Retrieved Text: We must explore some fairly intricate hormonal issues if we want to understand the effects of a high-carbohydrate diet on insulin and glucagon ratios. While the body is blessed with an enormous capacity to maintain homeostasis in a very unbalanced world, its homeostatic mechanisms are not infinite. If we want to maintain homeostatic balance and thus keep our weight under control, we must learn how these unbalanced hormones cause weight gain and what we can do to stop their squabbling.
First of all, we need to understand how eating a diet high in carbohydrates affects blood sugar, because the secretion of insulin and glucagon is determined by the level of sugar in the blood.
Think about the source of carbohydrates. Foods like apples, carrots, pasta, cereals, potatoes, rice, baked beans, candy bars, potato chips, and soft drinks have at least one thing in common: They are sugars. Complex carbohydratesraw fruits, grains, and vegetablescontain complex sugars called disaccharides or polysaccharides, two or more sugar molecules bound together by molecules of water.1 Because these sugars are too large to be absorbed into the bloodstream and burned as energy, they must be digested into single molecules, or simple sugars, for conversion to blood sugar (glucose). The tough fibers encasing these molecules in complex carbohydrates are very beneficial to the body because they help sweep the intestinal tract clear of dietary debris, encourage the proliferation of friendly bacteria, lower blood fats, and eliminate used estrogens from the body.
Both simple and complex carbohydrates must be broken down into glucose to be used for

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Rank: 9
Score: 67.00843
Retrieved Text: Biochemical catalysis by enzymes can hydrolyse starch in very specific ways.
α-Amylase breaks the starch chain in such a fashion as to produce only minor amounts of low and medium molecular weight sugars but major amounts of soluble higher saccharides.
β-Amylase breaks the starch chain at every other unit bond, producing optimal quantities of the disaccharide maltose.
Glucoamylase hydrolyses the starch chains unit by unit, producing large amounts of dextrose in the hydrolysate.
Pullulanase or isoamylase hydrolyse the branching points of amylopectin allowing higher maltose and glucose yield.
Current processes use thermostable bacterial α-amylase in the first step breaking down the starch into oligosaccharides, which are then broken into glucose molecules by use of fungal glucoamylase.
Dr Michael Radeloff is a carbohydrate chemist from Hamburg University. He held several international management positions in the starch industry in R&D, Product Development and Marketing. Michael is the owner of Thales-Consult Berlin, a long established consultancy specialised in renewable agricultural raw materials, their derivatives and applications. The consultancy services are addressing client product development strategies, are analysing market opportunities, provide technical product application assessments and develop in-house customer training programmes.

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Rank: 10
Score: 65.985214
Retrieved Text: The energy patterns of carboxypeptidase, enterokinase, lactase, lipase, lysozyme, maltase, pepsinogen, pepsin, peptidase, amylase, sucrase, trypsin, etc. 16 vials / ampules for use in testing by naturopaths, kinesiologists, EAV practioners, NAET practitioners and others who are similarly qualified.
Peptides into other peptides and amino acids (protein digestion).
Protein into peptides (protein digestion).
Converts deoxyribonucleic acid nucleotides(DNA) into pentoses and nitrogenous bases.
Converts inactive trypsinogen into active trypsin in small intestine (protein digestion).
Small intestine Converts lactose into glucose and galactose.
Converts fat into fatty acids and glycerol (fat digestion).
Destroys bacteria and so helps prevent tooth decay; works to limit the growth of the bacteria that cause infections and diarrhoea, and encourage the growth of good bacteria.
Converted by hydrochloric acid into pepsin (protein digestion).
Converts proteins into peptides (protein digestion).
Peptides into amino acids(protein digestion).
Milk protein into casein which allows pepsin to act on it.
Converts ribonucleic acid (RNA) into pentoses and nitrogenous bases.
Polysaccharides into maltose, which is a disaccharide (carbohydrate digestion).
Small intestine Sucrose into glucose and fructose.
Protein into peptides; activates procarboxypeptidase into carboxypeptidase (protein digestion).
There are more enzymes in the Body Biochemical Test Kits.

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Rank: 11
Score: 65.56294
Retrieved Text: Numerous enzymes are involved in breaking down different compounds in food as it passes through the digestive tract. Amylase is found in two main areas – saliva in the mouth and pancreatic juice in the pancreas. Pancreatic juice is secreted into the small intestine where it helps continue digestion. In both areas amylase helps to break down starch into simpler sugars.
Amylase produced in the mouth is known as salivary amylase and in the pancreas it is known as pancreatic amylase. Both are forms of alpha-amylase, the main type found in humans and other animals. Amylase breaks down starch, a type of insoluble carbohydrate produced by plants to store energy into smaller glucose units. It does this by successively cleaving the linkages between glucose molecules, forming first smaller soluble starches and eventually maltose and dextrin.
Like most enzymes, amylase requires certain conditions for its activity. In the mouth and pancreas, it needs an optimum pH of 6.7 to 7.0. It also works best at human body temperature and needs various other compounds to be present. In the stomach, conditions are quite different from those in the mouth. The presence of gastric acid makes the stomach strongly acidic, with a pH during digestion of around 1.0 to 3.0. This is outside the range at which amylase can work.
However, salivary amylase is not inactivated as soon as it reaches the stomach. Since being secreted in the mouth, it has continued to remain active as food is swallowed and passed through the esophagus. From here, food passes into the first part

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Score: 64.996475
Retrieved Text: The primary source of muscle energy production is Adenosine Triphosphate ->ATP). To produce ATP, living cells draw glucose from glycogen, a long-chain complex carbohydrate stored nearby in the muscles or liver. Each muscle store of glycogen has a chemical structure nearly identical to common starch and similar to long-chain maltodextrin. Glycogen is an endogenous Glucans Polysaccharide, very complex carbohydrate consisting of long-chains of glucose linked together. During exercise, the body's first choice is reducing glycogen to individual glucose molecules, which are shuttled into tiny mitochondria cells, which convert glucose to ATP for energy metabolism. Complimentary fat and amino acids ->from lean muscle tissue) are mobilized to postpone rapid depletion of glycogen and makeup any glycogen glucose shortfalls. ATP synthesis from muscle glycogen is the most efficient energy source, regenerating over double the rate energy from fat and lean muscle protein combined.
Glycogen, ->or "animal starch"), has a structure identical to plant starch Amylopectin. Starchy foods with the highest % of Amylopectin are structurally most like human muscle glycogen. Spirulina is the only known food source that contains pure glycogen ->24% of its calories from complex carbohydrates are "pure"glycogen.) Potato starch is the 2nd food-like glycogen and a close 3rd is grain maltodextrins.
Starch is a white, granular or powdery, odorless, tasteless, complex carbohydrate, ->C6H10O5)x, abundant in the seeds of cereal plants and in bulbs and tubers. Molecules of starch are made of hundreds or thousands of atoms, corresponding to values of x, as given in the formula above, that range from about 50 to many thousands. Native starch

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Rank: 13
Score: 64.84372
Retrieved Text: Carbohydrates – sugars, starches, and fibre – are sources of energy in common commercial pet foods, if used responsibly. However, irresponsible carb contents of current commercial pet food offerings is the reason for the current raw feeding debate taking place. That said, the body of the pet actually contains only small amounts of unused carbs; carbs in the diet that your fur kids do not need is stored as glycogen and body fat. Plants, however, contain a large amount of carbs and are included in most commercial diets to provide energy, fibre or as a filler.
Natural sugar and starches found in plants are useful for supplying energy and are more easily digested by your fur kids, given the correct source is selected. However, you should avoid feeding excess sugars, especially man-made sugars, that is often added by commercial pet food companies to increase the flavouring in processed foods. This is due to sugars competing with essential dietary nutrients for digestion and absorption, and in most cases, contribute to obesity. In the long term, high sugar contents may also predispose your fur kids to diabetes.
With a few exceptions, most dogs and cats have no established dietary requirement for carbohydrates. - this notion has been acknowledged by many academia as well as the U.S. Pet Food Manufacturer's Association [ref] (requires Adobe PDF Reader) themselves.
Once digested and absorbed by your fur kids, one of three things can happen to the sugars and starches: they are immediately used for energy, they are stored as glycogen in the liver (to be

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Rank: 14
Score: 64.82697
Retrieved Text: NOW PHASE 2 helps you achieve dietary managment objectives without the use of stimulants or laxatives. PHASE 2 is an all-natural bean extract that has been shown in non-clinical studies to help reduce the breakdown and abosrption of complex carbohydrates, by limiting the action of alpha-amylase, a digestive enzyme.
Alpha-amylase helps break down dietary starches into glucose so that they can be absorbed by the digestive tracts. With less alpha-amylase activity, there may be less excess glucose available to convert into fat and store as adipose tissue.
Now you don't have to feel bad about consuming carbohydrates. NOW Starch Neutralizer works by neutralizing the enzymes in the digestive system responsible for converting carbs to fat. Clinical studies show that Phase 2 white kidney bean extract really works.
One eight week study found that individuals who took Phase 2 carb blocker lost 129% more weight than the rest of the participants. Each capsule blocks more than 1,000 calories of starch. Multiple clinical studies that have proven its safe for consumption and effective at blocking carbs.
Suggested Use: As a dietary supplement, take 3 Vcaps® before any meal containing complex carbohydrates or starches, or as directed by a health care practitioner.
Free of: sugar, salt, yeast, wheat, gluten, corn, soy, milk or preservatives.
Other Ingredients: Cellulose (capsule), Cellulose and Gum Acacia. Vegetarian Formula.

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Rank: 15
Score: 64.39739
Retrieved Text: We don't hide behind our label. The CARBION+ formulation reads like a published journal of highly engineered carb sources. Every carb, electrolyte and insulin-receptor sensitizing ingredient is clearly listed. Some call it Transparent Label Protocol. We call it telling the truth. Take a look at other carb products and see if they have some random undisclosed blend of rice, corn and potato.
Train with CARBION+ and never look back.
Why Do I Need a Carb Drink?
Carbohydrates are the most effective and readily available workout fuel you can take.
Properly supplemented, they provide a highly stable and reliable energy source for optimal performance - shifting to fat metabolism and protein breakdown via gluconeogenesis is dramatically less effective and reduced performance is the result.
Recovery from intense training and replenishment of glycogen stores.
to power you through the toughest training."
Starting at the high end, AWM2300™ Waxy Maize is highly-branched and extremely complex and comes in at 200,000 g/mol, next in order of complexity is the Rice and Potato starch, while lower in inclusion rates, they are also very high on the molecular weight scale, and range between 80,000 and 120,000 g/mol, CCD™: Clustered Cyclic Dextrin is derived from Waxy Maize (Amylopectin) and has a molecular weight of 60,000 g/mol and finally, DE-5™: Dextrin is the least complex coming in at 45,000 g/mol; all far larger and more complex than the monosaccharides Glucose, Dextrose or Fructose which is 180 g/mol.
the length of the chain of glucose molecules"
The degree of complexity of carbohydrates indicates the length of the chain of glucose molecules; at the very

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Rank: 16
Score: 64.334175
Retrieved Text: White beans are the protein rich vegetable, loaded with minerals, vitamins, and the best source of the dietary fiber. By adding them in your diet it offers you a wide range of the health benefits like promoting the digestive health & preventing heart disease. The white beans are squared and large at the edges, not like smaller beans, like navy beans.
α-Amylase blocker: Referred as phaseolamin, the lectin acts as the carbohydrate blocker just by preventing binding of the starch to enzyme, which breaks this down. It means that lesser carbohydrates will be absorbed in your body.
Carbohydrates get digested by enzymes found in pancreas and saliva. Plants have developed many amylase blockers as their defense mechanisms against mammals and insects feeding on them. So, α-amylase found in the white beans, is active against the human α-amylases. And this fat and carb inhibitor will bind to α-amylase enzyme & prevents access of starch. Thus, starch can’t get degraded and lesser sugars get absorbed by intestines.
Time: The blocking activity is achieved after ten to forty minutes. But, over 120 minutes are required if pH isn’t optimal.
pH level: The activity is highest in acid conditions.
Other active compound in white beans, phytohemagglutinin, generally binds to inner surface of small intestine. It triggers release of hormones that enhance satiety and prevents production of hormone causing hunger and suppressing appetite.
Because commercial kidney bean extracts had very low amylase blocker activity, concentrate was developed. This broke down α-amylases from small intestine and mouth and reduced intestinal amylase activity & starch digestion.

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Score: 64.307755
Retrieved Text: 1. Humans must ingest proteins, carbohydrates and lipids to maintain tissue and organ function.
2. Most of these nutrients consist of large polymers that must be broken down before they can be made available to the intestinal cells for transport.
3. Dietary proteins are cleaved by hydrolases with specificity for the peptide bond (peptidases).
4. Endopeptidases (aka Proteases): attack internal protein bonds liberating large peptide fragments.
NH3+, aminopeptidases or COO- terminus, carboxypeptidase.
1. Gastric HCl is responsible for the low pH <2 of gastric juice.
2. Gastric acid kills microorganisms and denatures dietary proteins preparing them for hydrolysis by proteases.
3. Gastric juices contain the acid stable proteases of the pepsin family, which produce large peptide fragments and some free amino acids.
4. Protein digestion at this stage is partial, as the amino acids and small proteins enter the duodenum, they trigger the release of cholectystokinin-pancreozymin (CCK-PZ) into the bloodstream.
This release initiates the secretion of protease zymogens from the pancreas and release of enteropeptidase in the gut.
1. The pancreatic juice is rich in the proenzymes of endopeptidase and the carboxypeptidases.
2. Enteropeptidase converts pancreatic trypsinogen to trypsin.
3. Trypsin autocatalytically activates more trypsinogen and other proenzymes, liberating chymotrypsin, elastase and the carboxypeptidases A and B.
1. Since pancreatic juice does not contain appreciable aminopeptidase activity, final digestion of di- and small peptides depends on brush border enzymes.
2. The surface of intestinal epithelial cells is rich in endopeptidases and aminopeptidases.
3. The end products of cell surface digestion are free amino acids and di- and tripeptides.
1. Following digestion, amino acids and small peptides are co-absorbed w/ sodium via group

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Score: 63.845097
Retrieved Text: Ultimate Nutrition Carb Bloc at Netrition.com.
Carbs have been identified as one of the causes of weight gain for people who are having difficulty losing weight. Carbs are not easily burned by the body, and are stored as fat. Carbohydrates are found in almost any kind of food, even vegetables, not just bread and pasta. Research has proven that dietary fat is not necessarily converted into body fat. Carbohydrates, however, are readily converted into fat.
Ultimate Nutrition Carb Bloc helps block carbohydrate digestion. Carb Bloc is made with an extract from white kidney beans. This extract neutralizes the digestive enzyme alpha amylase before it can convert starch into glucose and then fat. Essentially, it allows the carbohydrates to pass through the system with possibly less caloric intake.
White kidney bean has been shown to be of great value in reducing the rate at which starch is converted into sugar in the digestive process, thereby reducing caloric intake. During the digestive process, the body converts carbohydrates in starchy foods such as potatoes and pasta into sugar. The body produces sugar by breaking down the carbohydrate molecule with alpha amylase, an enzyme produced in the pancreas. These sugar calories are either burned off through exercise or stored as fat cells for future use.

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Score: 62.668175
Retrieved Text: If we talk about the “timing” post-workout nutrition we should talk about protein and carbohydrates. Because it is a fairly broad topic, we try only what carbohydrates take and when to take them.
In this article we will focus on carbohydrate sources that we can find from sports supplement products. However, and as I mentioned in the section of questions, we can use directly source from this macro nutrient food. Still, it analyzes why certain people, perhaps more interested picking a product quickly absorbed, leaving then distributed other carbohydrate requirements during the day and also after other (s) session (s) training.
1 Why take carbohydrates after training?
2 How to store carbohydrates?
3 What is the rate of glycogen replenishment?
7 Are carbohydrates are necessary if we train once a day?
8 What is the maximum amount of carbohydrates a day?
Why take carbohydrates after training?
A clear example of what I mean we see in those athletes who train more than once a day, for example, a CrossFit athlete. Because of the nature that holds this discipline, especially with a view to a competitive event, the scheme planning and training are very high volume to accommodate complete all the necessary parameters to ensure a good performance during the competition (s).
Before going to rag on what carbohydrates are better or worse when it comes to recover from a workout, we must know which sites store glucose we eat. When we eat carbohydrates, such are digested and absorbed into the bloodstream in the form of glucose, which is directed to the muscle and liver glycogen

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Score: 62.405933
Retrieved Text: "عسى أن تكون علما ينتفع به"
4. Introduction Chickens are Omnivores An omnivore is a kind of animal that eats either other animals or plants. Meaning that, in addition to a commercial feed, they can eat meat (grubs, worms, the occasional mouse) and vegetation (grass, weeds and other plants).
6. Digestion Digestion is completed by the action of various enzymes secreted by different organs and accessory gland of the digestive system.
9. Organs and Functions The Mouth Mouth: It all starts here. A small bit of saliva and digestive enzymes are added as the food moves from the mouth into the esophagus.
10. Organs and Functions The Mouth Mouth (beak) is made up of: 1. Upper mandible – attached with skull – non-movable part of beak 2. Lower mandible – It is the movable part of beak  The chicken does not have teeth to chew its feed.
11. Cont. …  The roof of mouth is made up of hard palate that is divided by a long narrow slit in the center that is opened to the nasal passage.  The soft palate is absent in chicken.
12. Cont. …  The slit in the hard palate and the absence of soft palate make it impossible for the birds to create a vacuum to draw the water or feed into the mouth  Thus birds have to scoop up the water when drinking, elevates its head, and then let the water run down the gullet by the action of gravity.
15. Organs and Functions The Esophagus Esophagus: Transports food from the mouth

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Score: 62.25871
Retrieved Text: Amylases are secreted proteins that hydrolyze 1,4-alpha-glucoside bonds in oligosaccharides and polysaccharides, and thus catalyze the first step in digestion of dietary starch and glycogen.
Diurnal and stress-response salivary alpha amylase patterns were related to child adiposity: decreased morning alpha amylase was associated with increased BMI.
results show a strong association between acute physical stressor-induced elevations in sAA levels and patients with MDD.
These findings confirm that sAA is sensitive to the effects of potentially stressful stimuli (state variance) and at the same time demonstrate its relative robustness and stability across time and conditions (trait variance).
Amylases are secreted proteins that hydrolyze 1,4-alpha-glucoside bonds in oligosaccharides and polysaccharides, and thus catalyze the first step in digestion of dietary starch and glycogen. The human genome has a cluster of several amylase genes that are expressed at high levels in either salivary gland or pancreas. This gene encodes an amylase isoenzyme produced by the salivary gland.

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Score: 62.076347
Retrieved Text: The pancreas is a narrow, 6-inch long gland that lies posterior and inferior to the stomach on the left side of the abdominal cavity. The pancreas extends laterally and superiorly across the abdomen from the curve of the duodenum to the spleen. The head of the pancreas, which connects to the duodenum, is the widest and most medial region of the organ. Extending laterally toward the left, the pancreas narrows slightly to form the body of the pancreas. The tail of the pancreas extends from the body as a narrow, tapered region on the left side of the abdominal cavity near the spleen.
Glandular tissue that makes up the pancreas gives it a loose, lumpy structure. The glandular tissue surrounds many small ducts that drain into the central pancreatic duct. The pancreatic duct carries the digestive enzymes produced by endocrine cells to the duodenum.
The pancreas is classified as a heterocrine gland because it contains both endocrine and exocrine glandular tissue. The exocrine tissue makes up about 99% of the pancreas by weight while endocrine tissue makes up the other 1%. The exocrine tissue is arranged into many small masses known as acini. Acini are small raspberry-like clusters of exocrine cells that surround tiny ducts. The exocrine cells in the acini produce digestive enzymes that are secreted from the cells and enter the ducts. The ducts of many acini connect to form larger and larger ducts until the products of many acini run into the large pancreatic duct.
The endocrine portion of the pancreas is made of small bundles

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Retrieved Text: Digestive Enzymes: new information lists numerous health benefits of enzymes.
We could not assimilate our food without digestive enzymes, but these "micro-miracles allow our bodies to do so much more. Enzymes enable our bodies to break down and absorb the foods we eat, they help manufacture neurotransmitters that allow our nervous system to function properly, they help our body to heal when we are injured, they break down and carry away toxic substances, they purify the blood, they deliver hormones, they help the body to build muscle, and they are catalysts that allow metabolism to take place. There are more than 3,000 enzymes in our bodies, about 22 of which are digestive enzymes.
With regard to digestion, enzymes are present in every step of the digestion process. Three enzyme groups break down basic foods into materials our bodies can utilize: proteolytic enzymes (proteases); lipolytic enzymes (lipases); and amylolytic enzymes (amylases). Proteases break-down the twenty amino acids that compose protein, with each protease targeting a different amino acid. Lipases decompose various fats, including oils, lecithin (phospholipids), and cholesterol (sterols). Amylases break down the various sugars such as: sucrose, milk sugar, and fruit sugar.
Where do our Enzymes come from?
The three main categories of enzymes are: systemic (metabolic), digestive, and food. Food enzymes come from the foods we eat, whereas systemic and digestive enzymes are produced by our bodies. The majority of the enzymes produced by our bodies are systemic, and the human body can produces systemic enzymes as it requires. However, many nutrition experts believe that each of us inherits

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Retrieved Text: What is miglitol, and how does it work (mechanism of action)?
What brand names are available for miglitol?
Do I need a prescription for miglitol?
What is the dosage for miglitol?
Which drugs or supplements interact with miglitol?
Is miglitol safe to take if I'm pregnant or breastfeeding?
What else should I know about miglitol?
Miglitol is an oral medication used to control blood glucose (sugar) levels in type 2 diabetes. It belongs to a class of drugs called alpha-glucosidase inhibitors which also includes acarbose (Precose). Carbohydrates that are eaten are digested by enzymes in the intestine into smaller sugars which are absorbed into the body and raise blood sugar levels. The process of carbohydrate digestion requires the pancreas to release into the intestine alpha-amylase enzymes which digest the large carbohydrates into smaller carbohydrates called oligosaccharides. The cells lining the small intestine then release alpha-glucosidase enzymes that further digest the oligosaccharides into single sugars, like glucose, that can be absorbed. Miglitol is a man-made oligosaccharide designed to slow down the actions of alpha-amylase and alpha-glucosidase enzymes thereby slowing the appearance of sugar in the blood after a meal (postprandial hyperglycemia). It does not increase insulin production, and its effect on glucose is additive to the effect from other types of drugs used to treat type 2 diabetes. Miglitol may reduce the weight gain that frequently is caused by sulfonylureas, another type of drug used to treat type 2 diabetes. The FDA approved miglitol in December 1996.
The initial miglitol dose may start at 25 mg three times daily and then increase after four to

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Retrieved Text: Helps the bodys efforts to maintain blood sugar levels already within the normal range.
Carbo Grabbers contains an amylase inhibitor derived from northern white kidney beans which may help reduce the calories available to your body. It naturally and safely interferes with the digestion of starchy carbohydrates. Because the enzymatic breakdown of some dietary starch may be inhibited these undigested starches can be carried through the intestinal tract where the body can eliminate them. This makes avoiding carbohydratesa common practice among some dietersa thing of the past!
We added 18 mcg of patented food-bound chromium per serving. Chromium helps transport glucose from the blood into the cells. This means Carbo Grabbers provides additional help toward maintaining blood sugar levels already within the normal range. Chromium may also have a positive effect on blood fat levels.
Take 12 capsules up to three times daily before eating foods high in carbohydrates. Do not take in combination with digestive enzymes that contain proteases.

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Retrieved Text: Carbohydrates (CHOs) are a major fuel source for exercising muscle, especially in high-intensity or long-duration activities Carbohydrates can influence fluid absorption from the intestine (hydration) Some CHOs can cause gastrointestinal intolerance and thereby impair exercise performance Types of CHOs Exogenous: CHO intake from the diet Endogenous: CHO stored in the body (ie, glycogen) that can be used for energy needs Glycogen is stored glucose in the body It is a network of glucose molecules connected together, similar to starch United States Anti-doping Agency. Optimal dietary intake guide. Available at: Accessed January 31, 2011.
1. Free monosaccharides (1 sugar unit) Glucose (aka dextrose, from corn and other plants) Fructose (from fruit) Galactose (from milk) 2. Di-, tri-, oligo- (4 to 10 units), or polysaccharides (chain of 11+ monosaccharides) Sucrose (disaccharide of glucose + fructose) Lactose (disaccharide of glucose + galactose) Maltose (disaccharide of 2 glucose molecules) Trehalose (disaccharide of 2 glucose molecules, with a different linkage between the two) Starch (polysaccharide of glucose) Add pictures Berg JM, et al. Biochemistry. 5th ed. New York, NY: WH Freeman and Co; 2002.
Carbohydrates are absorbed as monosaccharides Enzymes must digest di-, tri-, oligo-, and polysaccharides into individual monosaccharides Enzymes exist in the saliva, stomach, and small intestine to break the different linkages between the various sugars There are special transporters in the cell membranes of intestinal cells that selectively absorb monosaccharides Monosaccharides are then transported into the blood stream, where they are distributed throughout the body Carbohydrates that escape digestion and absorption make their way to the colon (with variable degrees

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Retrieved Text: You will take a look at the major types of molecules found in living cells. Start off by exploring the function of molecules and then examine the factors that affect the activity of enzymes, and much more.
Describe the structure of carbohydrates.
List the functions of carbohydrates.
Give examples of different types of carbohydrates such as monosaccharides, disaccharides, and polysaccharides.
What atoms bond together to form carbohydrates? What are the constituents of carbohydrates?
What is a disaccharide? Give some examples of disaccharides.
~ When two monosaccharides come together, they form a disaccharide. Sucrose, or table sugar, is a disaccharide made from glucose and fructose. Lactose, or milk sugar, is another disaccharide made from galactose and glucose. Maltose is formed when two glucose molecules join together.
What is a polysaccharide? Give examples.
~ Sugars made up of more than two monosaccharides are polysaccharides, which are more complex molecules. Plants store starch, which is made from glucose. Humans store glucose as glycogen. Both starch and glycogen are polysaccharides. Cellulose is another polysaccharide that is used to build cell walls. In industrial production, cellulose is used to make paper. Chitin is also a polysaccharide that is found both in insects' shells and in fungi such as mushrooms.
Pre-requisite Concepts Students should be familiar with the terms biochemistry, biology, carbohydrate, carbon, and cellulose.

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Retrieved Text: Glucose contains six carbon atoms and an aldehyde group and is therefore referred to as an aldohexose. The glucose molecule can exist in an open-chain (acyclic) and ring (cyclic) form, the latter being the result of an intramolecular reaction between the aldehyde C atom and the C-5 hydroxyl group to form an intramolecular hemiacetal. In water solution both forms are in equilibrium, and at pH 7 the cyclic one is the predominant. As the ring contains 5 carbon and one oxygen atoms, which resembles the structure of pyran, the cyclic form of glucose is also referred to as glucopyranose. In this ring, each carbon is linked to an hydroxyl side group with the exception of the fifth atom, which links to a sixth carbon atom outside the ring, forming a CH2OH group.
Glucose has 4 optic centers which means that in theory glucose can have 15 optical stereoisomers. Only 7 of these are found in living organisms, and of these galactose (Gal) and mannose (Man) are the most important. These eight isomers (including glucose itself) are all diastereoisomers in relation to each other and all belong to the D-series.
An additional asymmetric center at C-1 (called the anomeric carbon atom) is created when glucose cyclizes and two ring structures, called anomers, can be formed — α-glucose and β-glucose. They differ structurally in the orientation of the hydroxyl group linked to C-1 in the ring. When D-glucose is drawn as a Haworth projection, the designation α means that the hydroxyl group attached to C-1 is below the plane of

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Retrieved Text: Equus Gold NB with Amylase is a concentrated source of essential nutrients designed to balance grains and roughage for protein, energy, vitamins and minerals to ensure that nutritional imbalances do not occur.
As a supplement to poor pasture for spelling.
Amylase Leading the Way – Naturally, Effectively & Safely!
Gold NB contains added Amylase to aid starch digestion in the small intestine naturally, effectively and safely without the need for expensive heat processing.
The addition of Amylase to Gold NB is one of the most advanced improvements in performance horse nutrition to occur in many years.
Amylase is a natural protein enzyme that is responsible for efficient starch digestion in the small intestine.
Horses do not produce adequate Amylase necessary for the digestion of large amounts of starch, this is why they have more problems digesting starch compared to other grain eating animals.
Lack of Amylase can result in incomplete starch digestion in the small intestine resulting in excessive undigested starch reaching the large intestine where it is fermented producing lactic acid. Excessive lactic acid can cause serious problems such as caecal acidosis which can lead to colic, laminitis, diarrhoea and poor fibre digestion.
Oat Free – For flexible diet formulation!
Gold NB does not contain oats as some feeding applications require an oat free diet. This allows for individual diets to be mixed to suit different horses within the stable.
Gold NB is balanced for essential amino acids, particularly Lysine, and as can be seen in the "Lysine" chart (below) contains a substantially higher level of lysine than typical horse feeds. The high lysine and

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Input Text: Answer the following question given this paragraph: 




Q: What part of the sporophyte produces microspores that form male gametophytes and megaspores that form female gametophytes?

 Choices:

- chloroplasts

- pollen

- flower

- leaves

A:

Target Text: flower

#### Retrieved Documents ####

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Retrieved Text: Angiosperm life cycle comprises of two generations, the Sporophytic and the Gametophytic. These two generations alternate with each other in regular sequence. This phenomenon is known as Alternation of Generation.
The angiospermic plant, that is usually differentiated into roots, stems, leaves and flowers, is the Sporophyte as it consists of diploid cells (2n). It is the dominant phase of the angiosperm life cycle. As a result of reduction division, it produces haploid Microspores and Megaspores. The Gametophytic phase (n) is represented by two structures, the Male Gametophyte and the Female Gametophyte. The male gametophyte is represented by the microspores (pollen grains) and the pollen tube with two sperm nuclei and a tube nucleus. The female gametophyte is generally, represented by eight-nucleate embryo sac. Both gametophytes are highly reduced and completely dependent on the sporophyte.
The reduction division occurs at the time of formation of microspores and megaspores and the diploid number is restored when zygote is formed. The zygote, therefore is the first cell of the sporophyte.
Another significant point is the formation of Endosperm. Endosperm in angiosperms is usually triploid as it develops from Primary Endosperm Nucleus formed as a result of the union of two polar nuclei and one sperm nucleus. It is thus formed after the process of fertilization.
During the course of evolution there has been gradual reduction and loss of independence in gametophytic generation whereas sporophytic generation has registered a gradual increase in size to attain even tree like proportions in angiosperms.
The oospore (thick-walled zygote) produces Embryo by segmentation; the ovule produces Seed and the

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Retrieved Text: Gymnosperms are naked seeded plants. Gynmosperms are a group of ancient plants. They become dominant in the Jurassic period Most of the gymnosperms are evergreen trees. Some shrubby pl..flas are also found in this group. They have worldwide distribution. They are most abundant in the temperate region. The fossils of gymnosperms are found near coal and oil deposits.
Gymnosperm shows a dear alternation of sporophytic and gametophytic generations. The plant body is sporophytic generation. The gametophytic is very much reduced. It had completely lost independent existence.
The plant body is a sporophyte. It is well differentiated into root, stem and leaves.
Roots: Primary or tap root is well developed. Root develops root caps.
without a reticulate venation. The branching of the veins is dichotomous type. Their leaves are modified to withstand the xerophytic conditions. The leaves have tough cuticle, sunken stomata and mesarch bundle. Stem: The stem is woody. Vascular bundles are collateral (arrange in rings) and open. They are arranged in a ring in the primary stem. Secondary growth takes plan by the activity of the cambium. It produces the secondary xylem (wood). Xylem is formed of xylem parenchyma and tracheid. They have no true vessels except the order Gnetales The phloem is formed of phloem parenchyma and sieve tubes. But they are without any companion cells. Primary cambium may remain active throughout the life of the plant. Then secondary and tertiary cambia are formed. It produces alternate zones of wood. The activity of phellogen produces bark on the surface.
Gymnosperms are heterosporous. They produce micro and megaspores. They develop

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Retrieved Text: "Ferns and Fern Allies;" "Vascular Cryptogams"
...freeliving, usually photosynthetic, but without vascular tissue, cuticle, and stomates, and hence inconspicuous and small (101 cm), confined to relatively moist situations.
...producing male and female gametangia, i.e. antherida and archegonia, respectively. Male gametes flagellated, female gametes sessile, within archegonium. Fertilization depends upon the availability of a film of liquid water within which sperm can swim to the archegonia (illustrations not to same scale, redrawn from Sporne 1975; images of prepared slides © 2009 Royal Ontario Mueum).
...independent of the gametophyte at maturity, photosynthetic, with vascular tissue, cuticle, and stomates, and hence varying considerably in size (101 - 103 cm) and complexity.
...producing spores in sporangia classified according to their development as eusporangiate or leptosporangiate (compare diagrams above, below). Spores all of one size (homosporous), or of two sizes (large, small; heterosporous).
...represented today by a variety of growth habits (life forms), hence occupying a wide range of habitats, notwithstanding the dependence on the availability of liquid water for sexual reproduction.
...as a group, much more abundant and diverse during the latter part of the Paleozoic and the Mesozoic than presently.
...dispersal occurs via spores, of whatever kind, i.e. by single cells however large.
...have only recently been examined in light of thinking about the theoretical importance of outcrossing.
...is the production of (two) different kinds of spores; microspores and megaspores.
...megaspore germinates to give rise to female gametophyte; microspore to male gametophyte, in both cases the gametophytes being retained within the spore wall.
...male prothallus reduced to a single antheridium from which varying numbers of motile sperm are released.
...female prothallus

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Retrieved Text: Download "Rhizarians. Forams. Radiolarians. Cercozoans"
14 Figure 29.3 Exploring Derived Traits of Plants Charophyte algae lack the key traits of plants described in this figure: alternation of generations; multicellular, dependent embryos; walled spores produced in sporangia; multicellular gametangia; and apical meristems. This suggests that these traits were absent in the ancestor common to plants and charophytes but instead evolved as derived traits of plants. Not every plant exhibits all of these traits; certain lineages of plants have lost some traits over time. Alternation of Generations The life cycles of all plants alternate between two generations of distinct multicellular organisms: gametophytes and sporophytes. As shown in the diagram below (using a fern as an example), each generation gives rise to the other, a process that is called alternation of generations. This type of reproductive cycle evolved in various groups of algae but does not occur in the charophytes, the algae most closely related to plants. Take care not to confuse the alternation of generations in plants with the haploid and diploid stages in the life cycles of other sexually reproducing organisms (see Figure 13.6). Alternation of generations is distinguished by the fact that the life cycle Mitosis n Alternation of generations: five generalized steps 5 The spores develop into multicellular haploid gametophytes. n MEIOSIS 1 The gametophyte produces haploid gametes by mitosis. Gametophyte (n) Spore includes both multicellular haploid organisms and multicellular diploid organisms. The multicellular haploid gametophyte ( gamete-producing plant ) is named for its production by mitosis of haploid gametes eggs and sperm that fuse during

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Retrieved Text: Bryophytes are the group of plants that are the closest extant relative of early terrestrial plants. The first bryophytes (liverworts) most likely appeared in the Ordovician period, about 450 million years ago. Because of the lack of lignin and other resistant structures, the likelihood of bryophytes forming fossils is rather small. Some spores protected by sporopollenin have survived and are attributed to early bryophytes. By the Silurian period, however, vascular plants had spread through the continents. This compelling fact is used as evidence that non-vascular plants must have preceded the Silurian period.
More than 25,000 species of bryophytes thrive in mostly damp habitats, although some live in deserts. They constitute the major flora of inhospitable environments like the tundra, where their small size and tolerance to desiccation offer distinct advantages. They generally lack lignin and do not have actual tracheids (xylem cells specialized for water conduction). Rather, water and nutrients circulate inside specialized conducting cells. Although the term non-tracheophyte is more accurate, bryophytes are commonly called nonvascular plants.
In a bryophyte, all the conspicuous vegetative organs—including the photosynthetic leaf-like structures, the thallus, stem, and the rhizoid that anchors the plant to its substrate—belong to the haploid organism or gametophyte. The sporophyte is barely noticeable. The gametes formed by bryophytes swim with a flagellum, as do gametes in a few of the tracheophytes. The sporangium—the multicellular sexual reproductive structure—is present in bryophytes and absent in the majority of algae. The bryophyte embryo also remains attached to the parent plant, which protects and nourishes it. This is a characteristic of

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Retrieved Text: Plants are multicellular organisms in the kingdom Plantae that use photosynthesis to make their own food. There are over 300,000 species of plants; common examples of plants include grasses, trees, and shrubs. Plants have an important role in the world’s ecosystems. They produce most of the world’s oxygen, and are important in the food chain, as many organisms eat plants or eat organisms which eat plants. The study of plants is called botany.
Plants are autotrophs; they produce their own food. They do so via photosynthesis, which is the process of making nutrients such as sugars from light energy and carbon dioxide. Photosynthesis occurs in cell organelles called chloroplasts, which contain chlorophyll and carotenoids, molecules that absorb light energy and change it into a usable form. Heterotrophs, on the other hand, are organisms that cannot make their own food and must eat other organisms to survive. Many heterotrophs eat plants. Other heterotrophs eat animals that have eaten plants. Plants are primary producers in many ecosystems, giving them a vital role in the survival of many other organisms. In addition, oxygen is a byproduct of photosynthesis, and many organisms depend on oxygen to survive. We couldn’t live without plants.
Plants are multicellular organisms with eukaryotic cells. A eukaryotic cell is a relatively large cell with a true nucleus and other organelles that perform specific functions. Plants, protists, fungi, and animals all have eukaryotic cells. Plant cells are distinguished by their cell walls containing cellulose, chloroplasts that perform photosynthesis, and a large central vacuole that holds water and keeps the

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Retrieved Text: Boisson-Dernier, A; Roy, S; Kritsas, K; Grobei, M A; Jaciubek, M; Schroeder, J I; Grossniklaus, U (2009). Disruption of the pollen-expressed FERONIA homologs ANXUR1 and ANXUR2 triggers pollen tube discharge. Development, 136(19):3279-3288.
The precise delivery of male to female gametes during reproduction in eukaryotes requires complex signal exchanges and a flawless communication between male and female tissues. In angiosperms, molecular mechanisms have recently been revealed that are crucial for the dialog between male (pollen tube) and female gametophytes required for successful sperm delivery. When pollen tubes reach the female gametophyte, they arrest growth, burst and discharge their sperm cells. These processes are under the control of the female gametophyte via the receptor-like serine-threonine kinase (RLK) FERONIA (FER). However, the male signaling components that control the sperm delivery remain elusive. Here, we show that ANXUR1 and ANXUR2 (ANX1, ANX2), which encode the closest homologs of the FER-RLK in Arabidopsis, are preferentially expressed in pollen. Moreover, ANX1-YFP and ANX2-YFP fusion proteins display polar localization to the plasma membrane at the tip of the pollen tube. Finally, genetic analyses demonstrate that ANX1 and ANX2 function redundantly to control the timing of pollen tube discharge as anx1 anx2 double-mutant pollen tubes cease their growth and burst in vitro and fail to reach the female gametophytes in vivo. We propose that ANX-RLKs constitutively inhibit pollen tube rupture and sperm discharge at the tip of growing pollen tubes to sustain their growth within maternal tissues until they reach the female gametophytes. Upon arrival, the female FER-dependent signaling cascade is activated to mediate pollen

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Retrieved Text: The life cycle of a fern is complex compared to that of a flowering plant, and the cycle involves both sexual and asexual reproduction. Some ferns are able to produce new plants entirely asexually, but usually a fern's reproductive process includes a sexual stage.
Ferns differ from flowering plants in that they don't reproduce via seeds. Instead, most ferns produce tiny seedlike structures called spores, and when the spores germinate, they grow into new plants that begin the next stage in the life cycle. In flowering plants, seeds are produced sexually, which means they contain a mixture of genetic material from distinct sperm and egg cells that may come from different plants. Fern spores, however, are produced asexually, which means their genetic material is identical to that of the parent fern.
This asexual stage, though, is only the first step in a fern's life cycle. The next step involves sexual reproduction.
Fern spores are dispersed by wind or water, and when they land in a place with the right growing conditions, which typically involves plenty of moisture and shelter from direct sunlight, the spores germinate and grow into tiny plants called gametophytes. Most ferns' gametophytes are very small compared to the size of the parent plants, and they may go entirely unnoticed as they develop.
Gametophytes develop sexual organs and produce sperm and egg cells. One gametophyte's egg cell may be fertilized by a sperm cell from a nearby gametophyte, or the little plant may fertilize itself. Even if the egg is self-fertilized, however, the new plant that grows from

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Retrieved Text: The high elevations and relatively low temperatures of Cameron Highlands brings about a persistent fog that surrounds the rainforest, reducing the sunlight that reaches the canopy which in turn drops the rates of evapotranspiration. Because of this, the water retention in these 'cloud forests' is very high as the fog ends up condensing on the leaves, which then drips down to the ground. Epiphytes abound in conditions like this. They grow on other organisms such as on the trunks of trees, but unlike parasites, they obtain their nutrients and water from the air instead of through their hosts.
Unfortunately, because cloud forests depend so heavily on the climate, these delicate ecosystems are strongly affected by climate change. The 'heating up' and 'drying out' of these temperate zones will inevitably lead to the death of epiphytes, and an overall decline in the biodiversity of these areas.
As you walk along the path, you may occasionally see stalks portruding from the moss that look almost like bean sprouts. These are the stalks of mature sporophytes and they support something called a 'sporangium' that both produces and stores spores for reproduction. The release of these spores then gives rise to new gametophyte plants. The gametophytes produce male and female gametes that then go on to form the zygote, which in turn becomes a newly emerging sporophyte.
Other plants such as ferns also produce sporangium but they are instead located in 'nodules' that are arranged in lines along the leaf edges, something that veteran hikers are probably quite familiar with. The immature sporangia

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Retrieved Text: For the physician, see Stamen Grigorov.
The stamen (plural stamina or stamens, from Latin stamen meaning "thread of the warp") is the male organ of a flower. Each stamen generally has a stalk called the filament (from Latin filum, meaning "thread"), and, on top of the filament, an anther (from Ancient Greek anthera, feminine of antheros "flowery," from anthos "flower"), and pollen sacs, called microsporangia. The development of the microsporangia and the contained haploid gametophytes, (called pollen-grains) is closely comparable with that of the microsporangia in gymnosperms or heterosporous ferns. The pollen is set free by the opening (dehiscence) of the anther, generally by means of longitudinal slits, but sometimes by pores, as in the heath family (Ericaceae), or by valves, as in the barberry family (Berberidaceae). It is then dropped, or carried by some external agent — wind, water or some member of the animal kingdom — onto the receptive surface of the carpel of the same or another flower, which is thus pollinated. It is the part that contains the sperm cells.
Typical flowers have six stamens inside a perianth (the petals and sepals together), arranged in a whorl around the carpel (pistil). But in some species there are many more than six present in a flower (see, for example, the spider tree flower, below). Collectively, the stamens are called an androecium (from Greek andros oikia: man's house). The anthers are bilocular, i.e. they have two locules. Each locule contains a microsporangium. The tissue between the locules and the cells is called the connective. In an

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Retrieved Text: Like all plants Toxicodendron diversilobum exhibits an alternation of generations. This means that during the life cycle of the plant it alternates between a multicellular diploid sporophyte generation and a multicellular haploid gametophyte generation. Since the Pacific poison oak is in the phylum Angiosperm it has a dominant sporophyte generation which means that the gametophyte generation will be more dependent on the sporophyte generation.
The first part of the angiosperm life cycle takes place in the flower of the plant. Here in the anther the microsporocytes develop and undergo meiosis which produces haploid microspores. Each microspore undergoes one division of mitosis to form a generative cell and a tube cell. Together they form an immature pollen grain. The generative cells then go through a second mitotic division which produces two sperm nuclei. Inside the ovule one megaspore undergoes meiosis to form four haploid megaspore. Three die off and one remains. The remaining megaspore undergoes three mitotic divisions and generates an 8 nucleate embryo sac also known as a megagametophyte.
Next pollination occurs. The pollen grain germinates on the stigma where a pollen tube grows down into the style. Eventually it grows down into the ovary through the micropyle. One sperm nucleus then fuses with the egg which creates a diploid zygote, and the other sperm fuses with the central cell of the egg to form the endospore.
Now that the embryo has formed it grows inside the embryo sac. The ovule creates a protective seed coat around the embryo and embryo sac. Then the seed is dropped from fruit

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Retrieved Text: The objective of this study was to examine the effects of temperature and light intensity on growth of female gametophytes of Eisenia bicyclis and Ecklonia cava and responses of these female gametophytes to Fe addition and daylength. Female gametophytes of each species were cultured at four temperatures (10, 15, 20, and 25℃) and under a combination of four light intensities (10, 20, 40, and 80 μmol photons/(m2·s)) with two temperatures (15 and 20℃ for Ei. bicyclis; 20 and 25℃ for Ec. cava) to clarify their optimal growth conditions. Growth and maturation of female gametophytes of these two species under a combination of five Fe-EDTA concentrations (0, 1, 2, 4, and 8 μmol/L) and three daylengths (10, 12, and 14 h) were also examined. The growth of Ei. bicyclis gametophyte was maximal at approximately 15-20℃, 20 μmol photons/(m2·s), Fe-EDTA concentration of 8 μmol/L and daylengths of 12-14 h. While Ec. cava gametophytes showed optimal growth at approximately 20-25℃, 20 μmol photons/(m2·s), FeEDTA concentration of 8 μmol/L and daylength of 14 h. Maturation of gametophytes was enhanced at Fe-EDTA concentration of 4 μmol/L for Ei. bicyclis and at 2 μmol/L for Ec. cava. In conclusion, optimal growth temperatures and Fe-EDTA concentrations for maturation of Ei. bicyclis and Ec. cava gametophytes were different. Higher optimal growth temperature for Ec. cava gametophytes may contribute to its wider geographical distribution compared to Ei. bicyclis which has restricted habitats in Korea. This suggests that addition of Fe ion could be used to recover beds of these two species in barren grounds of

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Retrieved Text: Steeves, T.A.. "Seed Plants". The Canadian Encyclopedia, 04 March 2015, Historica Canada. https://www.thecanadianencyclopedia.ca/en/article/seed-plants. Accessed 21 April 2019.
The common feature uniting seed plants is the "seed habit," a unique method of sexual reproduction. In all vascular plants, the conspicuous plant is a spore producer (sporophyte) that alternates, in the life cycle, with a sexual phase (gametophyte).
Seed Plants, the most abundant and familiar component of Earth's vegetation, comprise an estimated 250 000-300 000 species. They outnumber all other PLANT groups, dominate the land, thrive in bodies of fresh water and are found to a limited extent in the oceans. They include the largest (giant sequoia) and oldest (bristlecone pine) living things, and encompass tiny water-meal scarcely 1 mm long and ephemeral annuals that survive only a few weeks. Seed plants share with other vascular plants (plants with woody conducting systems) basic organs (root, stem and leaf), cell types and tissues. In response to different environments, they have evolved many forms.
The common feature uniting seed plants is the &QUOT;seed habit,&QUOT; a unique method of sexual reproduction. In all vascular plants, the conspicuous plant is a spore producer (sporophyte) that alternates, in the life cycle, with a sexual phase (gametophyte). In seed plants, the spore that produces the female gametophyte is not shed to initiate an independent plant but is retained in the sporangium (reproductive structure), which is surrounded by a protective covering (integument). This is the immature seed or ovule.
Spores that produce male gametophytes are released as the gametophytes begin to develop. These are the pollen grains which are

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Retrieved Text: This is one of a series of short articles about ferns in Belfast Botanic Gardens, compiled by members of the Friends group (FoBBG).
The Killarney fern is one of the filmy ferns, a group of delicate plants restricted to very moist conditions. There are some 350 species of Trichomanes of which the Killarney fern is the only one native to the British Isles; the rest are mostly tropical and epiphytic, typically growing on the trunks of trees in tropical rain-forests.
Description Leaves 8-25cm long with a long wiry stalk growing out of a black scaly rhizome. The blade is repeatedly divided with the margins of the segments untoothed (Photo 1). The leaves are mostly one cell thick and translucent except along the midrib. Spores are produced in sporangia in a flask-shaped sorus with a distinct bristle which persists after the spores are shed (Photo 2).
The gametophyte stage of the life-cycle is filamentous. As well as producing the male and female gametes that lead to a new sporophyte plant, the gametophyte produces asexual gemmae that will grow into more gametophyte plants. The gametophyte plant can remain sterile and spread and multiply by the gemmae. The gametophyte plant is more common in the wild than the sporophyte and can easily be mistaken for an alga.
Habitat Beside waterfalls, in crevices between boulders, under overhanging rocks and other shady, damp, sheltered situations. In Ireland the Killarney fern has been largely exterminated by enthusiastic fern collectors, but a few small wild populations do survive.
The Killarney fern in Belfast Botanic Gardens For a long

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Retrieved Text: The water ferns are so-called because of their aquatic or semi-aquatic habitats. There are two families the free-floating mosquito ferns, Azolla and Salvinia, and the rhizomatous clover ferns, Marsilea, Regnellidium, and Pilularia. The two pair of pinnae (leaflets) sported by Marsilea look a bit like clover, but the venation is all wrong, so they used to use them in the manufacture of good luck charms where they were embedded in plastic as a fob in lieu of getting lucky enough to actually find a four-leafed clover. Regnellidium has just one pair of pinnae, and Pilularia has no pairs having a pinnae-less frond (a pun-loving friend used to call this the "pauper" fern). These ferns grow in shallow water their rhizome rooted along the bottom. The leafier genera have emergent leaves, while the leafless genus can grow completely submerged. Azolla is used in aqua-culture, primarily rice paddies, because it has a symbiotic interaction with the cyanobacterium Anabaena, a nitrogen-fixer. They do lots of interesting things in addition. They form seed-like fertile leaves for surviving droughts. They are the only heterosporous ferns, large spores forming female gametophytes, and small spores forming male gametophytes, modifications for rapidly getting through the haploid phase of their life cycle. And they look pretty cool although not very fern-like in the traditional sense. The image shows one node of Salvinia with a whorl of three leaves, two floating leaves, and a root-like disected submerged leaf, which is also the fertile frond (round sori are visible).

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Retrieved Text: 1. the process of reproduction.
2. a class composed of all individuals removed by the same number of successive ancestors from a common predecessor, or occupying positions on the same level in a genealogical (pedigree) chart.
alternate generation reproduction by alternate asexual and sexual means in an animal or plant species.
asexual generation (direct generation) production of a new organism not originating from union of gametes.
first filial generation the first-generation offspring of two parents; symbol F1.
parental generation the generation with which a particular genetic study is begun; symbol P1.
second filial generation all of the offspring produced by two individuals of the first filial generation; symbol F2.
sexual generation production of a new organism from the cell formed by the union of a male gamete (spermatozoon) and a female gamete (oocyte).
spontaneous generation the discredited concept of continuous generation of living organisms from nonliving matter.
reproduction by fission, gemmation, or in any other way without union of the male and female cell, or conjugation.
Reproduction by fission, gemmation, or in any other way without union of the male and female cells, or conjugation.
Synonym(s): heterogenesis (2) , nonsexual generation.
2. a class composed of all individuals removed by the same number of successive ancestors from a common predecessor, or occupying positions on the same level in a genealogical (pedigree) chart. Said also of antibiotics or other chemicals derived from parent compounds.
reproduction by alternate asexual and sexual means in an animal or plant species.
production of a new organism not originating from union of gametes. Called also direct generation.
the first generation offspring of two parents; symbol F1.
all of

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Retrieved Text: Broad beech fern has broadly triangular leaves that tilt backward from their long, upright stalks. Wings of leafy tissue connect the main leaf lobes along the main axis.
Broad beech fern is a perennial fern growing from branching, creeping, hairy rhizomes that have yellow or light brown, shiny scales. Leaf stalks are straw-colored, scaly or hairy at the base, hairless above. Stalks are usually longer than the blade, and the blades often tilt back from the tip of the upright stalk. Blades are triangular in general outline, deeply twice-pinnately lobed; the primary lobes are mostly connected by wings of leafy tissue along the main vein (rachis), with the lowest divisions rarely free. Lobes are hairy above and below, with small, stalked glands and scattered scales along the midrib of the undersurface. Lobes are themselves lobed or toothed. Spore clusters have round, with small, stalked glands and lack coverings (indusia). Spores are produced June–September.
Similar species: Northern beech fern (P. connectilis) occurs in western Illinois and might one day be found in eastern Missouri. It is smaller, and the lowest pair of leaflets are free (not winged).
Leaf length: 6–30 inches (includes stalk and leaf blade, from ground to leaf tip).
Even in small, young leaves of broad beech fern, the bottommost lobes usually point downward, while the other lobes spread out from the main axis at mostly right angles. Note the winged axis.
Occurs in moist soils of wooded slopes along streams, in ravines, and on blufftops, mostly on acidic substrates, but also on limestone and dolomite. Occurs less commonly along

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Retrieved Text: McCarthy, Mirabai , Hickey, R. James .
Bryophyte Influence on Terrestrial and Epiphytic Fern Gametophytes.
The unique climate and structural complexity of tropical forests enable vertical habitat differentiation between terrestrial and epiphytic zones. These habitats are spatially overlapping in nature and there are no known barriers to dispersal of fern spores between them. Because spores are copiously released, one might expect to find species growing in both places, yet taxa are typically confined to one particular habitat type. The goal of this study was to better understand how epiphytic and terrestrial species are restricted by habitat. Epiphytic, Phlebodium aureum, Neurodium lanceolatum, Campyloneuron phyllitidis, and terrestrial Adiantum tenerum, Thelypteris augescens, and Pteris bahamensis were collected in the tropics as spore sources. Three epiphytic substrates (moss, leafy liverwort, and lichen) and one terrestrial substrate (soil) were also collected. Spores of each species were discretely sown directly onto these substrates and onto agar-substrate combinations, then placed in a growth chamber under uniform conditions where development was monitored. Gametophytes of all terrestrial species sown directly on leafy liverwort were significantly reduced in size and throughout the duration of this study never reached sexual maturity. On agar-bryophyte combinations we identified a positive correlation between distance from the epiphytic substrates and the size of terrestrial gametophytes. In contrast, gametophytes of epiphytic species developed normally regardless of media and substrate. These observations suggest the possibility that epiphytic bryophytes have a negative impact on terrestrial gametophyte development, perhaps through allelopathy. Such interactions between substrate and terrestrial gametophytes might represent a limiting factor for the establishment of

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Retrieved Text: When one walks through a contemporary forest, all of the surrounding trees are vascular plants. Wood, which is made up primarily of xylem , and bark, which contains phloem , are the major structural elements of the trunks and stems. These trees produce seeds, whether they be formed within the cones of the pines or within fruits, such as the winged samaras of maples or the fleshy cherries of the cherry tree. In the Carboniferous period a similar hike would also place one in a forest of woody trees, many as large as 98 feet (30 meters) tall, but there would be no seeds produced. These plants were seedless vascular plants, which were propogated by spores. Ultimately they became extinct, leaving behind expansive fossil fuel deposits.
The differences between spores and seeds are extensive. Seeds are multicellular structures that provide a protected place where the egg (n) was to be fertilized by male gamete nuclei (n) in pollen. The resulting cell, called a zygote , is diploid (2n), the same as the original plant that produced it. It repeatedly divides mitotically, while still within the protection of the seed coat, to form an embryo. The embryo may remain dormant for a significant time period but ultimately emerges from the seed when it germinates.
The seedless vascular plants do not have this protection. Their gametes are produced mitotically by a gametophyte (n) that lives independently. There are often many vase-shaped archegonia on these small plants, and the unfertilized egg is inside the base of this structure. The embryo formed

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Retrieved Text: The nonvascular plants, characterized by life cycles dominated by the gametophyte phase. This group includes the mosses, liverworts, and hornworts, which lack lignified conducting tissues.
Alternate term applied to the angiosperm female gametophyte contained within a megaspore .
The reproductive structures in angiosperm sporophytes where gametophytes are generated.
A plant, or phase of a plant's life cycle, that bears gamete s.
The haploid stage of a plant exhibiting alternation of generations , generates gametes by the process of mitosis .

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Retrieved Text: Both angiosperms and gymnosperms are seed bearing land plants. Gymnosperm plants evolved about 200 million years before Angiosperm plants. Therefore, angiosperms are considered to be more advanced plant group than gymnosperms.The main difference between Angiosperm and Gymnosperm is that the diversity of angiosperms is greater than that of the gymnosperms; this indicates the high adaptability of angiosperm to terrestrial ecosystems. Both angiosperm and gymnosperm plants are heterosporous, produce two types of spores as microspores and megaspores. One of the conspicuous features of angiosperms is the formation of flower, which cannot be seen in gymnosperms. Flower is a modified shoot which carry modified micro and megasporophylls. In gymnosperms, microsporophylls are connected together to form male cones (strobile), and megasporophylls are connected together to form female cones. The other main feature is the production of fruits by angiosperm. Ovules later converted to seeds in both groups. However, in angiosperms ovules are enclosed by an ovary wall that is later converted to fruit. In gymnosperms, seeds are not enclosed in a fruit (naked) and, therefore, ovules are directly borne on megasporophylls.
The name angiosperm (greek angion, container) denotes the seeds content in fruits or mature ovaries. These plants bear flowers, a special structure carrying reproductive organs and fruits, ovaries that contain mature ovules. All angiosperms are included in one phylum known as Anthophyta (Anthos in greek – flower). Today Anthophyta are the most diverse and widespread plant group on earth, with more than 250,000 species. Further, these species fall into two large categories, the monocots and dicots. The basic differentiation

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Retrieved Text: Bug moss, bug-on-a-stick, humpbacked elves, elf-cap moss… Who knew there could be so many names for such tiny mosses. Despite their small stature, the mosses in the genus Buxbaumia have achieved something of a celebrity status to those aware of their existence. To find them, however, you need a keen eye, lots of patience, and a bit of luck.
Buxbaumia comprises something like 12 different species of moss scattered around much of the Northern Hemisphere as well as some parts of Australia and New Zealand. They are ephemeral in nature, preferring to grow in disturbed habitats where competition is minimal. More than one source has reported that they are masters of the disappearing act. Small colonies can arise for a season or two and then disappear for years until another disturbance hits the reset button and recreates the conditions they like.
I say you must have a keen eye and a lot of patience to find these mosses because, for much of their life, the exist on a nearly microscopic scale. Buxbaumia represents and incredible example of a reduction in body size for plants. Whereas the gametophytes of most mosses are relatively large, green, and leafy, Buxbaumia gametophytes barely exist at all. Instead, most of the “body” of these mosses consists of thread-like strands of cells called “protonema.” Though all mosses start out as protonema following spore germination, it appears that Buxbaumia prefer to remain in this juvenile stage until it comes time to reproduce.
Considering how small the protonemata are, there has been more than a little confusion

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Retrieved Text: Cytological observation of chromosome breakage in wheat male gametophytes caused by gametocidal action of Aegilops triuncialis-derived chromosome 3Ct.
Copyright © 2016 Laboratory of Plant Genetics, Graduate School of Agriculture, Kyoto University. All Rights Reserved.

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Retrieved Text: Nucleotide sequences encompassing the chloroplast rps4 gene and the rps4-trnS intergenic spacer were obtained for several specimens representing North American and Hawaiian members of Pteridium aquilinum (ingroup), as well as Pteridium esculentum (outgroup). Nucleotide divergence between ingroup bracken taxa was low. The rps4-trnS intergenic spacer contained indels distinguishing P. aquilinum and P. esculentum. Phylogenetic analyses and a haplotype network recognized two major groups within Northern American bracken that are divided along both genetic and geographic lines. The Hawaiian var. decompositum and the western North American var. pubescens share a similar chloroplast genome and grouped together. Despite morphology and geographical distribution, sequences for var. feei and eastern North American var. latiusculum were very similar and grouped together. Sequence data could not distinguish eastern North American var. latiusculum and the southeastern North American var. pseudocaudatum. Haplotype and biogeographic analyses suggest a most recent common eastern North American ancestor for the ingroup.
Most studies of spore germination in seedless vascular plants have involved species that develop surficial, photosynthetic gametophytes following spore germination. However, several species, including Lycopodium clavatum, give rise to subterranean, nonphotosynthetic, mycorrhizal gametophytes and their spores germinate in the dark. Red light, like white light, inhibits the germination of these spores. Germination occurs after exposure to far-red light. The effects of far-red light are reversed by red light and those of red light are reversed by far-red light confirming the involvement of phytochrome. The active form of phytochrome, Pfr, inhibits germination in L. clavatum. It appears that this is a general phenomenon in seedless vascular plants with subterranean,

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Retrieved Text: Showing results for tags 'sphagnum'.
Using pure sphagnum to grow sarrs.?
Hi there, Was wonsering about using just sphagnum moss with no other ingredient in the soil (no sand or perlite etc etc) to grow the sarracenia. Have seen people posting previously about how their sand or perlite has has made their soil anoxic so was hoping to avoid that with a pure sphagnum moss soil. Thankyou.
Hello everyone, last spring I had my first sporophytes on Sphagnum. They appeared on Sphagnum fimbriatum, a monoicous species. This means a single plant can produce both male and female reproductive cells (Both eggs and sperm cells). In order to have sporophytes on the dioicous Sphagnum species, you will need both a female and a male clone, but not for this S. fimbriatum. I decided to do a little experiment and grow Sphagnum from spores. While looking in the literature I read this article: 'Habitat requirements for establishment of Sphagnum from spores' (Sundberg et al., 2002). The authors found out that Sphagnum spore germination is limited by nutrients (phosphate). This means that Sphagnum spores germinate on places where there are more nutrients then where adult Sphagnum plants occur (usually nutrient-poor soils). I decided to do the experiment in three different setups. 3 small containers with blonde peat that has been cooked to kill all spores present. In one I added fertilzer but no spores, in the other I added spores of S. fimbriatum but no fertiliser and in the last one, both spores and fertilser (really low amount) was added. The experiment

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Retrieved Text: Durán, Monica; Anton, Ana M.
An account is given of the spore germination and young gametophytes of two species of Blechnum L and one hybrid B australe subsp auriculatum (Cav.) de la Sota; B. laevigatum Cav. and B. australe subsp, auriculatum x B laevigatum. In these taxa some young gametophytes tend to branch; branches were formed on the first, second or even the fourth cell in the filament Some of the branches end in a laminar portion while others remain filamentous.

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Retrieved Text: This biphasic life cycle that plants demonstrate is referred to as an?
The life cycle of a plant from?
The leafy green gametophyte is the haploid generation that produces sperm and eggs. The sperm must swim through a film of water to the egg. The zygote develops into a stalked, diploid sporophyte that emerges from the gametophyte plant. The sporophyte is topped by a brown capsule in which haploid spores are produced by meiosis. These are dispersed and germinate, producing another green gametophyte generation.
What is the function and structure of the flower?
Flowers are the part of the sporophyte generation in flowering plants that is dedicated to sexual reproduction.
Insect and vertebrate pollination is ____ efficient than wind pollination.
that put more efforts into mechanisms to attract the animals (i.e. nectar, odoriferous compounds, appearance and etc.) ensured the success of those flowering plant lineages.
Stamens and carpels are composed of two to three distinctly different parts.
1.) To recap pollination is when a pollen grain lands on the stigma of a flower's carpel.
2.) The pollen generates a tube to transfer the sperm from the male gametophyte to the female gametophyte.
3.) In flowering plants we see a double fertilization from the fusion of the sperm to specific cells of female gametophyte.
4.) This double fertilization gives rise to a zygote and endosperm.
5.) When the female gametophyte develops in the manner previously illustrated (polygonum type), which is the most common, the double fertilization gives rise to a (2n) zygote and a (3n) endosperm.
How do seeds germinate and grow?
Seeds need moisture and warmth to germinate. If conditions

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Retrieved Text: Angiosperms, or flowering plants, are the most numerous of all the divisions in the Plant Kingdom. With the exception of extreme habitats, angiosperms populate every land biome and aquatic community. They are a major food source for animals and humans, and are a major economic source for the production of various commercial products. Angiosperms differ from non-vascular plants in that they have a vascular transport system for moving water and nutrients to various parts of the plant.
The parts of a flowering plant are characterized by two basic systems: a root system and a shoot system. The root system is typically below ground and serves to acquire nutrients and anchor the plant in the soil. The shoot system consists of the stems, leaves, and flowers. These two systems are connected by vascular tissue. Vascular tissues called xylem and phloem are composed of specialized plant cells that run from the root through the shoot. They transport water and nutrients throughout the plant.
Leaves are an important component of the shoot system as they are the structures through which plants acquire nutrition by photosynthesis. Leaves contain organelles called chloroplasts that are the sites of photosynthesis. Gas exchange needed for photosynthesis occurs through the opening and closing of tiny leaf pores called stomata. The ability of angiosperms to shed their foliage helps the plant to conserve energy and reduce water loss during cold, dry months.
The flower, also a component of the shoot system, is responsible for seed development and reproduction. There are four main flower parts in angiosperms: sepals, petals, stamens,

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Retrieved Text: A subclass of the true mosses (Bryopsida) largely limited to the South Pacific. The subclass consists of a single genus, Dawsonia, of nine species. The gametophytes are remarkably similar to those of the Polytrichidae, but the origin and structure of the peristome are very different.

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Retrieved Text: The embryo sac is also known as the female gametophyte or megagametophyte. In the angiosperm the ovule contains a reduced sac like structure known as the embryo sac which is embedded in the sporophytic tissue.
Any plant has two components a gametophyte (haploid) and a sporophyte (diploid).As we move from lower plants like bryophytes ,where main plant body is gametophyte and sporophyte is dependant on gametophyte , to higher plants like angiosperms where main plant body is sporophyte and gametophyte(pollen grain in male flower and embryo sac in female flower) is dependant on the sporophyte ;that is the whole plant ,the size of gametophyte gets reduced and the gametophyte becomes dependant on the sporophyte.thus the embryo sac(present in female flower ) which is haploid is called as female gametophye.
In pines the female gametophyte contains?

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Input Text: Answer the following question given this paragraph: 

Paranasal Sinuses The paranasal sinuses are hollow, air-filled spaces located within certain bones of the skull (Figure 7.18). All of the sinuses communicate with the nasal cavity (paranasal = “next to nasal cavity”) and are lined with nasal mucosa. They serve to reduce bone mass and thus lighten the skull, and they also add resonance to the voice. This second feature is most obvious when you have a cold or sinus congestion. These produce swelling of the mucosa and excess mucus production, which can obstruct the narrow passageways between the sinuses and the nasal cavity, causing your voice to sound different to yourself and others. This blockage can also allow the sinuses to fill with fluid, with the resulting pressure producing pain and discomfort. The paranasal sinuses are named for the skull bone that each occupies. The frontal sinus is located just above the eyebrows, within the frontal bone (see Figure 7.17). This irregular space may be divided at the midline into bilateral spaces, or these may be fused into a single sinus space. The frontal sinus is the most anterior of the paranasal sinuses. The largest sinus is the maxillary sinus. These are paired and located within the right and left maxillary bones, where they occupy the area just below the orbits. The maxillary sinuses are most commonly involved during sinus infections. Because their connection to the nasal cavity is located high on their medial wall, they are difficult to drain. The sphenoid sinus is a single, midline sinus. It is located within the body of the sphenoid bone, just anterior and inferior to the sella turcica, thus making it the most posterior of the paranasal sinuses. The lateral aspects of the ethmoid bone contain multiple small spaces separated by very thin bony walls. Each of these spaces is called an ethmoid air cell. These are located on both sides of the ethmoid bone, between the upper nasal cavity and medial orbit, just behind the superior nasal conchae.


Q: The paranasal sinuses are hollow, air-filled spaces located within certain bones of the skull. all of the sinuses communicate with the nasal cavity (paranasal = “next to nasal cavity”) and are lined with this?

 Choices:

- respiration mucosa

- fluid mucosa

- oral mucosa

- nasal mucosa

A:

Target Text: nasal mucosa

#### Retrieved Documents ####

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Retrieved Text: Definition (MSH) One of the paired air spaces located in the body of the SPHENOID BONE behind the ETHMOID BONE in the middle of the skull. Sphenoid sinus communicates with the posterosuperior part of NASAL CAVITY on the same side.
Definition (NCI_NCI-GLOSS) A type of paranasal sinus (a hollow space in the bones around the nose). There are two large sphenoid sinuses in the sphenoid bone, which is behind the nose between the eyes. The sphenoid sinuses are lined with cells that make mucus to keep the nose from drying out.
Definition (NCI) Either of the paired paranasal sinuses, located in the anterior part of the body of the sphenoid bone and communicating with the superior meatus of the nasal cavity on the same side.

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Retrieved Text: Acute sinusitis is caused by streptococci, pneumococci, Haemophilus influenzae, or staphylococci and is usually precipitated by an acute viral respiratory tract infection.
In acute sinusitis, penicillin V 250 mg po q 6 h is the initial antibiotic of choice, and erythromycin 250 mg po q 6 h is the second choice.
Sinusitis not responsive to antibiotic therapy may require an operation (maxillary sinusotomy, ethmoidectomy, or sphenoid sinusotomy) to improve ventilation and drainage and to remove inspissated mucopurulent material, epithelial debris, and hypertrophic mucous membrane.
Sinuses are hollow air spaces in the human body.
The ethmoid sinuses are near the tear ducts in the corner of your eyes.
At least two-thirds of sinusitis cases caused by bacteria are due to two germs that can also cause otitis media (middle ear infection) in children as well as pneumonia and acute worsening of chronic bronchitis.
Sinusitis is an acute (very intense) or chronic (happening repeatedly or all the time) inflammation of the nasal sinuses - hollow cavities within the cheek bones found around the eyes and behind the nose.
Sinusitis can affect the nose, eyes, or middle ear, and may be indicated by plentiful, thick, colored nasal drainage, bad-tasting post-nasal drip, cough, head congestion and an accompanying headache.
Rhinitis is an inflammation of the mucous membranes of the nose - not the sinuses.
Sinusitis occurring during the first week of upper respiratory infection is usually viral in origin.
Most commonly allergic fungal sinusitis occurs in response to a variety of species, and tends to involve multiple sinuses and is associated with and eosinophilic infiltrate.
Complications of acute bacterial sinusitis inlcude:

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Retrieved Text: Paranasal sinuses. Coloured 3D computed tomography (CT) scan of the paranasal sinuses. The paranasal sinuses are spaces in the bones surrounding the eyes and nose, and the cheek bones of the upper jaw. They lighten the bones of the skull and reduce the weight of the head. They are connected to the nasal passages and are lined with mucous membranes. They can fill with fluid and secrete mucus during an infection.

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Retrieved Text: Paranasal sinuses, artwork. The paranasal sinuses are spaces in the bones surrounding the eyes and nose, and the cheek bones of the upper jaw. They lighten the bones of the skull and reduce the weight of the head. They are connected to the nasal passages and are lined with mucous membranes. The paranasal sinuses are: the frontal sinus (purple, in forehead), the ethmoid sinus (yellow), the sphenoid sinus (green) and the maxillary sinus (light blue).

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Retrieved Text: What is CT of the Sinuses?
A CT scan of the face produces images that also show a patient’s paranasal sinus cavities. The paranasal sinus are hollow, air-filled spaces located within the bones of the face and surrounding the nasal cavity, a system of air channels connecting the nose with the back of the throat. There are four pairs of sinuses, each connected to the nasal cavity by small openings.
The technologist begins by positioning patients on the CT examination table. For a CT scan of the sinuses, the patient is positioned lying flat on the back. The patient may also be positioned face-down with the chin elevated. Straps and pillows may be used to help the patient maintain the correct position and to hold still during the exam. Some patients require an injection of a contrast material to enhance the visibility of certain tissues or blood vessels. A nurse or technologist will insert an IV line into a small vein in the patient’s hand or arm. The contrast material will be injected through this line. Next, the table will move quickly through the scanner to determine the correct starting position for the scans. Then, the table will move slowly through the machine as the actual CT scanning is performed. You may be asked to hold your breath during the scanning. Any motion, whether breathing or body movements, can lead to artifacts on the images. This is similar to the blurring seen on a photograph taken of a moving object.
When the examination is completed, you will be asked

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Retrieved Text: air cavities in the cranial bones that communicate with the nasal cavity by means of narrow canals or fissures.
The maxillary sinus, or antrum of Highmore, is located in the maxillary bone; the opening connecting it to the nasal cavity is situated in the meatus nasi medius. The frontal sinus is located between the membranes of the orbital part and the squama frontalis; it communicates with the nasal cavity by way of the nasofrontal duct, which opens into the anterior part of the meatus nasi medius. The ethmoidal labyrinth consists of two to five or more air cells of varying size and shape. The anterior cells open into the meatus nasi medius, and the posterior cells into the meatus nasi superior. The sphenoidal, or wedge-shaped, sinus is located in the body of the sphenoid bone immediately behind the ethmoidal labyrinth; the anterior wall of each half of the sinus has openings that connect it to the nasal cavity.
The mucous membrane lining of the paranasal sinuses is similar in structure to that of the nasal cavity but is considerably thinner and relatively lacking in vessels and glands. The most common disturbances of the paranasal sinuses are caused by inflammations of their mucosa, or sinusitis, and by traumas.
It is more commonly seen in Larynx, paranasal sinuses and salivary glands.
Computed tomography study of paranasal sinuses pathologies.
Allergy may produce a spectrum of changes in paranasal sinuses varying from mild mucosal thickening to complete opacification of the sinus (Fig.
Sinonasal polyposis is a typically extensive process with involvement of both the nasal cavity

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Retrieved Text: The pull of the planets. Pull pull pull.
I usually can’t be bothered pointing out superstition and debunking it. When people ask me what star-sign I am, I generally let them know I’m a Cancer. Such a question is generally followed up with some kind of observation about my personality that fits with the Cancer-ian dealy. Or an exclamation about some other reason why that’s meaningful.
Ultimately, people are just so pervasively superstitious that to run around constantly pointing out the folly would occupy most of my time and certainly wouldn’t win me too many friends. So I choose not to. However!
There exists no known force which is a suitable candidate for creating astrological influence.
Based on astrology’s own set of conditions, there seems to be no possible unknown force either.
That cold reading and human pattern-bias explain accurate-seeming predictions.
That astrology’s claims are not consistent, nor even internally consistent – and utterly lack any predictive power.
Finally, that reliance upon astrology creates actual, demonstrable harm.
Scattered throughout, there are a bunch of links to help illustrate this position. Give it a read! If you’re wondering how I got here, it’s from a much more recent blog post of his about a nutjob named Terry Nazon’s attacks on an astronomer named Stuart Robbins following a good debunking. Check that out too, if you like!
You may or may not be aware that I’ve had noggin trouble for the past month or so. Consequently, I’ve become a little preoccupied with sinuses and their buried mysteries.
Sinus is a generic term derived from latin – it means

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Retrieved Text: Leone Gold, Maria Eugenia.; Brusatte, Stephen.; Norell, Mark.
Archosaurs and mammals exhibit skeletal pneumaticity, where bone is infilled by air-filled soft tissues. Some theropod dinosaurs possess extensively pneumatic skulls in which many of the individual bones are hollowed out by diverticula of three main cranial sinus systems: the paranasal, suborbital, and tympanic sinuses. Computed tomography (CT scanning) permits detailed study of the internal morphology of cranial sinuses. But only a few theropod specimens have yet been subjected to this type of analysis. We present CT scans of the remarkably preserved and disarticulated skull bones of the long-snouted tyrannosaurid theropod Alioramus. These scans indicate that Alioramus has extensive cranial pneumaticity, with pneumatic sinuses invading the maxilla, lacrimal, jugal, squamosal, quadrate, palatine, ectopterygoid, and surangular. Pneumaticity is not present, however, in the nasal, postorbital, quadratojugal, pterygoid, or angular. Comparisons between Alioramus and other theropods (most importantly the closely related Tyrannosaurus) show that the cranial sinuses of Alioramus are modified to fill the long-snouted skull of this taxon, and that Alioramus has an extreme degree of cranial pneumaticity compared to other theropods, which may be the result of the juvenile status of the specimen, a difference in feeding style between Alioramus and other theropods, or passive processes. Based on these comparisons, we provide a revised terminology of cranial pneumatic structures and review the distribution, variation, and evolution of cranial pneumaticity within theropod dinosaurs. This review illustrates that most theropods possess a common "groundplan" in which the maxilla and lacrimal are pneumatized, and that various theropods modify this groundplan by pneumatizing

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Retrieved Text: You’re coughing and sneezing and tired and achy. You think that you might be getting a cold. Later, when the medicines you’ve been taking to relieve the symptoms of the common cold are not working and you’ve now got a terrible headache, you finally drag yourself to the doctor. After listening to your history of symptoms and perhaps doing a sinus X-ray, the doctor says you have sinusitis.
Sinuses are hollow air spaces, of which there are many in the human body. When people say, “I’m having a sinus attack,” they usually are referring to symptoms in one or more of four pairs of cavities, or spaces, known as paranasal sinuses. These cavities, located within the skull or bones of the head surrounding the nose, include the frontal sinuses over the eyes in the brow area, the maxillary sinuses inside each cheekbone, the ethmoids just behind the bridge of the nose and between the eyes, and behind them, the sphenoids in the upper region of the nose and behind the eyes.
Most cases of acute sinusitis are caused by viruses and will clear up without treatment within two weeks. Viruses can enter the body through the nasal passages and set off a chain reaction resulting in sinusitis. For example, the nose reacts to an invasion by viruses that cause infections such as the common cold, flu, or measles by producing mucus and sending white blood cells to the lining of the nose, which congest and swell the nasal passages. When this swelling involves the adjacent mucous membranes of

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Retrieved Text: Definition - What does Ethmoid Sinus mean?
The ethmoid sinuses are a pair of air pockets located along the ethmoid bone and between the eyes. Within the bone structure of the skull, there are several open cavities referred to as the sinuses. The large, frontal sinuses are located at the center of the face above the eye sockets. Below the eyes on either side of the nose are the maxillary sinuses. Between the eyes on either side of the bone that forms the bridge of the nose are the smaller ethmoid and sphenoid sinuses. These cavities are collectively referred to as the paranasal sinuses.
The ethmoid sinuses are also called ethmoidal air cells.
The sinuses help the body filter air and produce mucus that moistens the nasal passages. The ethmoid sinuses are relatively small when compared to the sinuses situated above and below the eye sockets. When the sinuses become infected due to a cold or other illness, the condition is called sinusitis. In some instances, cancer may develop in the sinuses. Risk factors that can contribute to the development of ethmoid sinus cancer include exposure to chemical hazards such as chromium or nickel in the workplace.

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Retrieved Text: The ethmoid bone (also ethmoidal bone, ethmoid, latin: os ethmoidale) is an unpaired bone of the skull that contributes to the medial wall of the orbit, the nasal cavity and the nasal septum. The ethmoid bone includes the cribriform plate with openings that transmit the olfactory nerves (CN I), and it also houses paranasal sinuses called the ethmoidal air cells.
The cribriform plate of the ethmoid is a part of the ethmoid bone situated in the horizontal plane, covering the ethmoidal incisure. It forms the roof of the nasal cavity and part of the anterior cranial fossa of the internal cranial base. The cribriform plate has small openings which transmit the fibers of the olfactory nerves (CN I) from the olfactory epithelium (nasal cavity) to the brain (cranial cavity).
The perpendicular plate of the ethmoid is a part of the ethmoid bone situated in the sagittal plane below the cribriform plate. The lower part of the perpendicular plate forms the posterior nasal septum, while the upper part rises above the cribriform plate as the crista galli.
The ethmoidal air cells are air filled spaces in the ethmoidal labyrinth of the ethmoid bone belonging to the paranasal sinuses. There can be distinguished anterior, middle, and posterior ethmoidal air cells.
The orbital plate of the ethmoidal labyrinth is a thin bony plate found in the ethmoid bone, covering the ethmoidal cells from the orbital side and forming the lateral surface of the labyrinth.
The superior nasal conchae and the middle nasal conchae are a part of the ethmoid bone, while the inferior nasal

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Retrieved Text: The individual gas-exchanging manhood, the lung, also is currently found in the thorax, in which its fragile tissues are protected from the bony and muscle thoracic cage. The lung stipulates the cells of your body using a constant stream of oxygen and also clears the bloodstream of this gaseous waste productcarbon dioxide, carbon dioxide. Atmospheric air is pumped in and out frequently via a system of pipes, also known as running airways, which combine the gas-exchange area with the exterior the human body. The airways can be split into lower and upper airway systems.
The top airway system contains the nose and the paranasal cavities (or Illness ), the pharynx (or neck ), and partially also the nasal cavity, because it could possibly be used for the breathing. The diaphragmcalled the key neural muscle, along with the intercostal muscles of the chest wall play a vital role by creating, under the constraint of the central nervous system, the bending activity within the lung. The muscles contract and expand the inner distance of the thorax, the bony frame of which can be formed from the bones and also the nasal passages. The participation of the lung and chest wall (muscles and ribs ) into respiration is explained below at The mechanisms of breathing. The bloodstream, as a provider for those gases, as well as the circulatory system (i.e., both the heart and blood vessels) are compulsory components of a functioning circulatory system (notice bloodflow; cardiovascular procedure ).
It’s subdivided into a left and right artery with a lean lateral

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Retrieved Text: The sinuses are a connected system of hollow cavities in the skull. The largest sinus cavities are about an inch across. Others are much smaller.
Your cheekbones hold your maxillary sinuses (the largest).
The low-center of your forehead is where your frontal sinuses are located.
Between your eyes are your ethmoid sinuses.
In bones behind your nose are your sphenoid sinuses.
They’re lined with soft, pink tissue called mucosa. Normally, the sinuses are empty except for a thin layer of mucus.
Why do we have sinuses? Experts don’t know. One theory is that they help humidify the air we breathe in. Another is that they enhance our voices.
Acute sinusitis (sinus infection): Viruses, bacteria, or fungi infect the sinus cavity, causing inflammation. More mucus; nasal congestion; discomfort in the cheeks, forehead, or around the eyes; and headaches are common symptoms.
Deviated septum : If the septum that divides the nose is too far too one side, airflow can be blocked.
Hay fever ( allergic rhinitis ): Allergens like pollen, dust mites, and pet dander cause the defenses in the nose and sinuses to overreact. Mucus, nasal stuffiness, sneezing, and itching result.
Nasal polyps aresmall growths in the nasal cavity. They can happen due to inflammation from asthma, chronic sinus infections, and nasal allergies (such as hay fever).
Turbinate hypertophy: The ridges on the nasal septum are enlarged, which can block airflow.
Physical examination : A doctor can look into the nose with a lighted viewer to see the turbinates, which may be swollen. She may press or tap on the face over the sinuses to check for pain.
Computed

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Retrieved Text: Sinus infections are very common as well as annoying. Sinus infections actually are an inflammation of the sinus cavities and this may be caused by bacteria, allergies, fly, cold etc. Fortunately there is a natural drug-free remedy for this infection and we will present you the most effective ones.... A runny nose can be just as annoying, even embarrassing, especially when you’re surrounded by people and all your attention is put on constantly blowing your nose and cleaning your face.
Sinuses are air pockets located behind the bones of the upper face, between the eyes, and behind the cheeks, nose and forehead. In other words, they are literal air spaces in the skull and facial bones.... A runny nose can be just as annoying, even embarrassing, especially when you’re surrounded by people and all your attention is put on constantly blowing your nose and cleaning your face.
A runny nose can be just as annoying, even embarrassing, especially when you’re surrounded by people and all your attention is put on constantly blowing your nose and cleaning your face. how to clear form history on google chrome Clear out your #sinuses using only your fingers in a matter of seconds! Instead of using #medicine, give this a try first. #NaturalRemedies #NaturalMedicine #Allergies #SinusProblems Instead of using #medicine, give this a try first.
Sinuses are air pockets located behind the bones of the upper face, between the eyes, and behind the cheeks, nose and forehead. In other words, they are literal air spaces in the skull and facial bones.
Nasya is considered

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Retrieved Text: Most head and neck cancers begin in the cells that line the mucosal surfaces in the head and neck area, e.g., mouth, nose, and throat. Mucosal surfaces are moist tissues lining hollow organs and cavities of the body open to the environment. Normal mucosal cells look like scales (squamous) under the microscope, so head and neck cancers are often referred to as squamous cell carcinomas. Some head and neck cancers begin in other types of cells. For example, cancers that begin in glandular cells are called adenocarcinomas.
Oral cavity - includes the lips, the front two-thirds of the tongue, the gums, the lining inside the cheeks and lips, the floor (bottom) of the mouth under the tongue, the hard palate (bony top of the mouth), and the small area of the gum behind the wisdom teeth.
Larynx - the larynx, also called the voicebox, is a short passageway formed by cartilage just below the pharynx in the neck. The larynx contains the vocal cords. It also has a small piece of tissue, called the epiglottis, which moves to cover the larynx to prevent food from entering the air passages.
Paranasal sinuses and nasal cavity - the paranasal sinuses are small hollow spaces in the bones of the head surrounding the nose. The nasal cavity is the hollow space inside the nose.
Salivary glands - the major salivary glands are in the floor of the mouth and near the jawbone. The salivary glands produce saliva.
Sometimes, cancerous squamous cells can be found in the lymph nodes of the upper neck when there

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Retrieved Text: The nasal cavity is a roughly cylindrical, midline, airway passage that extends from the nasal ala anteriorly to the choana posteriorly. It is divided in the midline by the nasal septum. On each side, it is flanked by the maxillary sinuses, and roofed by the frontal, ethmoid, and sphenoid sinuses, in an anterior to posterior fashion. While seemingly simple, sinonasal anatomy is composed of intricate and subdivided air passages and drainage pathways that connect the sinuses.
There are 4 paired sinuses in humans. They are all in line with pseudostratified columnar epithelium.
The maxillary sinuses: Largest of the paranasal sinuses, located under the eyes in the maxillary bones.
To develop a strong understanding of paranasal sinus anatomy, it is also important to understand the anatomical relationships of the sinuses to surrounding structures. The lateral nasal wall contains many structures and recesses that are important for understanding paranasal sinus anatomy.
Osteomeatal complex (OMC): Region referring to the anterior ethmoids containing the ostia of the maxillary, frontal, and ethmoid sinuses. This is located lateral to the middle turbinate. While not a discrete anatomic structure, it is instead a collection of several middle meatus structures including the middle meatus, uncinate process, ethmoid infundibulum, anterior ethmoid cells, and ostia of the anterior ethmoid, maxillary, and frontal sinuses.
Nasal Fontanelles: Area of the lateral nasal wall where no bone exists. The natural ostium of the maxillary sinus is located in the anterior fontanelle.
The maxillary sinus is located under the eyes in the maxillary bone. Adjacent structures include the lateral nasal wall, the orbital floor, and the

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Retrieved Text: What is Sinusitis? How Do You Relieve It.
Knowing the root cause of sinusitis will aid you in better understanding of how to alleviate the constant problems that it can bring. Here we will discuss the symptoms and treatments that are available.
Sinus infectionsSinusitis is known as inflammation of the sinuses. Sinusitis is one of the more common conditions that can upset people all the way through their lives. Sinusitis usually happens after a cold due to bacteria and diseases infecting the lining of the sinuses. Sinusitis, in turn, is produced by either a respiratory infection (such as a cold) or allergies (like hay fever, also called allergic rhinitis). Sinusitis can be small( which may last from 2 to 8 weeks) or constant, with symptoms lasting much longer.
Sinuses are hollow empty spaces within the bones of the face. Sinuses assist in insulating the skull, reduce its weight, and allow the voice to ring within it. Sinuses also help heat up and humidify the air that passes through the nose.
Symptoms of sinusitis can be quite inconsistent, both in whether or not they are at hand and how serious they are. Symptoms. sinus infection has its own localized pain signals, depending upon the individual sinus affected. Symptoms of Sinus Infections. A sinus can feel like a brutal toothache or like a headache with soreness under the eyebrows. Symptoms may include distress of breathing through the nose, headaches, throbbing behind the eye area, painfulness in the cheeks, sinus congestion, nasal discharge, or post nasal drip. Symptoms that docrop up are nonspecific

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Retrieved Text: The two most common kinds of skin cancer are basal cell carcinoma and squamous cell carcinoma. Basal cell carcinoma accounts for more than 90 percent of all skin cancers in the United States. It is a slow-growing cancer that seldom spreads to other parts of the body. Squamous cell carcinoma also rarely spreads, but it does so more often than basal cell carcinoma. However, it is important that skin cancers be found and treated early because they can invade and destroy nearby tissue.
Basal cell carcinoma and squamous cell carcinoma are sometimes called nonmelanoma skin cancer. Another type of cancer that occurs in the skin is melanoma, which begins in the melanocytes.
Oral Cavity – The oral cavity includes the lips, the front two-thirds of the tongue, the gums (gingiva), the lining inside the cheeks and lips (buccal mucosa), the bottom (floor) of the mouth under the tongue, the bony top of the mouth (hard palate), and the small area behind the wisdom teeth.
Salivary Glands – The salivary glands are in several places: under the tongue, in front of the ears, and under the jawbone, as well as in other parts of the upper digestive tract.
Paranasal Sinuses & Nasal Cavity – The paranasal sinuses are small hollow spaces in the bones of the head surrounding the nose. The nasal cavity is the hollow space inside the nose.
Pharynx – The pharynx is a hollow tube about 5 inches long that starts behind the nose and leads to the esophagus (the tube that goes to the stomach) and the trachea

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Retrieved Text: Deutsche Seite / German Version.
An average of 2500 surgical procedures from the entire range of ENT operations are performed at the Clinic for Ear, Nose and Throat Medicine annually. The main focus is hereby placed on surgery of the ears and the petrosal bone as well as the nose and the paranasal sinuses. In addition to acoustic neuromas, the range of treatments includes implants which improve hearing, microscopic and minimally invasive interventions on the ears and the nose as well as plastic surgery.
The surgical treatment of tumours in the ear, nose and throat area, also play a major role at the Clinic. In order to perform medical ENT examinations, the Clinic has state-of-the-art equipment to cover the complete range of ENT diagnostic procedures. This makes it possible to provide soundproof booths for diagnostic hearing tests, ultrasound diagnostics with colour-coded Doppler, otoneurological examinations with brain stem auditory invoked potentials, videonystagmography and acoustic emissions as well as rhinomanometry, olfactory testing and allergy tests.
Furthermore, the Clinic has one of the most state-of-the-art digital volume tomography devices. This makes it possible to produce high-resolution images of bones in the skull, specifically the base of the skull and the paranasal sinuses, which display these with an unforeseen accuracy.

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Retrieved Text: There are four paired paranasal sinuses: maxillary, ethmoid, frontal and sphenoid.
Maxillary sinuses are located in the cheek area and can cause facial pain that may radiate to the teeth.
Ethmoid sinuses are located between the eyes and can cause pain that radiates to the eye area.
Frontal sinuses are located in the forehead and can cause frontal headaches and pressure.
Sphenoid sinuses are located in the center of the skull and can cause pain radiating to the top and back of the head. The sinuses, eyes, and ears all drain into the nose.
Symptoms of sinus disorders vary widely. Here are some tips addressing common issues that affect our sinuses.
1 – Keep Kleenex Handy.
Clearing secretions by gently blowing your nose rather than inhaling alleviates sinus blockage and pressure.
2 – Use an Expectorant.
3 – The Common Cold is usually a Virus.
A virus after four to five days tends to block the sinuses and may trigger a Bacterial Sinus Infection. Unlike the common cold virus, bacterial sinus infections are generally not contagious.
Headaches, pressure or pain in the sinus area.
Sore throat and coughing from a backdrip.
Facial swelling. Acute sinusitis usually feels like a prolonged cold.
Chronic sinusitis may be more difficult to diagnose. Prolonged symptoms of headache, facial pain or sinus pressure that fail to resolve after antibiotics may indicate a chronic condition.
5 – See a Specialist for Treatment Options.
If you have had two or more sinus infections, suffer from sinus pressure or headaches, it is best to seek out a specialist for an evaluation. An Ear, Nose and Throat Specialist (Otolaryngologist) can help

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Retrieved Text: Home > Healthy & Happy > Kill Sinus Infection Within Minutes, With What You Have In Your Kitchen!
A sinus infection, also known as sinusitis, is an inflammation of the tissue lining of the sinuses.
Healthy sinuses are filled with air, but when blocked, germs can grow within and cause an infection. Symptoms of sinusitis include fevers, facial pain, and headaches while the most common causes include allergic rhinitis, common cold, deviated septum, and nasal polyps.
There are two types of sinusitis: acute and chronic. The first one typically lasts up to a month while chronic sinusitis may last 12 weeks or longer. Viruses and bacteria which grow in the air spaces within the bones in the cheek bones, forehead, and between the eyes cause thick mucus and extreme discomfort in these areas.

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Retrieved Text: But also of Christmas future.
Or, perhaps, the spirit (pneuma) of the season.
Merry Christmas to all! We’ll see you back here in 2009.
In view of all the awesome that is the Humboldt Museum’s gigantic brachiosaur mount, it’s too easy to overlook another nearly-complete Tendaguru sauropod, mounted in the very same hall, that is also worthy of respect and, yes, awe. Ladies and gentlemen, I give you: Dicraeosaurus hansemanni!
Dicraeosaurus hansemanni mounted skeleton, Humboldt Museum, Berlin. Anterolateral view. Matt Wedel for scale.
Dicraeosaurus is a member of Dicraeosauridae, the family that, together with Diplodocidae makes up the whip-tailed clade Flagellicaudata; which in turn, with rebbachisaurids and a few bits and pieces, makes up the great neosauropod clade Diplodocoidea. Dicraeosaurus was first named and briefly described by Janensch (1914:83); typically, Janensch went on to make full and detailed descriptions of its osteology, and also to describe the mounted skeleton (Janensch 1936).
It’s not really apparent from the photo above, but Dicraeosaurus is really small — like, embarrassingly small. Especially when it’s standing next to Brachiosaurus brancai. Gunga et al. (1999) estimated its mass at 12810 kg, but since that was the same paper that estimated B. b. at 74420 kg, based on a similarly grotesque baloon model, we can probably assume an accurate mass would be about one third of that, or 4000-5000 kg. Smaller than a big elephant. (I don’t know of any other published mass estimates for Dicraeosaurus; if I’ve missed any, please shout.) This is typical for dicraeosaurs: the South American Amargasaurus and Brachytrachelopan are even smaller.
Dicraeosaurus neck. Left

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Retrieved Text: Sinus pain can be one of the most debilitating and uncomfortable conditions to experience. Often caused by inflammation of the sinuses, using a sinus inhaler such as the Mypurmist steam inhaler, will bring natural sinus pressure relief.
When not properly drained, mucous builds up in the sinuses and they can become inflamed. Inflammation can be the result of a cold or flu virus as well as from untreated hay fever. These conditions lead to a block nose which in turn block the sinuses.
There are four pairs of sinuses in the human head. The largest ones are located behind the cheekbones and in the forehead. The sinuses are air filled cavities that are lined with mucous. The mucous is continually being swept from the sinuses into the nose to moisten the air we breathe and to keep the nasal passages clear of allergens and pollutants, removing these to the back of the throat where they generally go to the stomach and end up being expelled from the body.
Sinuses also act to lighten the bones of the skull and serve as sound-resonance chambers for speech.
Sinus or a cold or the Flu?
A sinus infection often occurs after a cold or the flu and is often thought of as a continuing symptom of either. Whereas a cold or flu will cause a lot of discomfort,sinus inflammation and congestion, however, can be quite painful and in chronic cases may last for several weeks to years.
Surgery may be necessary to treat patients with persistant and chronic sinusitis. The surgery which is called Functional

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Retrieved Text: Due to your use of sinus medicine high blood pressure increase is often experienced. Sinus medication or OTC (over-the-counter) drugs and dietary supplements have shown significant side effects if you have hypertension.
Since high blood pressure does not usually show any symptoms, and is also one of the causes of high blood pressure; if you must take sinus medicines take with precaution.
There are four pairs of sinuses within your head and they are the air-filled spaces above, behind and below your eyes.
Maxillary sinuses are located beneath your checks to the sides of your nose.
Your frontal sinuses are located in the bone above your eyes.
And the more deeper sinuses are Ethmoid and Sphenoid sinuses which lies deeper in your skull than any other sinuses.
Sinusitis means inflammation of the sinuses, and that is all the air-filled spaces above, behind and below your eyes. Your sinuses starts when your normal system of drainage is blocked.
Normal function of your nasal passage is that the hair cells sweeps your mucus along to flush out foreign particles and organisms such as bacteria, viruses and dust.
Whenever your mucus is not draining as it should, sinusitis starts.
Your normally thin sinus membranes swells blocking the openings from your sinuses into your nose, causing pressure and discomfort, along with feelings of congestion in your head.
Mucus build up in your sinus can become a breeding ground for bacteria making it very difficult for you to breathe. That is why you seek relief in sinus medicines.
Here is what you need to know about OTC or sinus medicine high blood

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Retrieved Text: Endoscopic sinus surgery - also called endoscopy or sinoscopy - is actually a process used to take out obstruction in the sinuses (the spaces filled up with air in some of the bones of the skull). These blockades cause sinusitis, a condition in which the sinuses get bigger and become clogged, causing pain and impaired breathing.
Thin, lighted instrument known as a great endoscope is inserted into the nose, and the doctor looks inside through an eyepiece. Very similar to a telescope with a wide-angle camera lens, the particular endoscope beams light into different parts of the nose and sinuses, permitting the doctor to see what is causing blockades. Medical tools can then be used along with the endoscope to remove the blockades and improve breathing.
This surgery does not involve cutting through the skin, as it is done entirely with the nostrils.
Endoscopic sinus surgery is a relatively new process designed to increase the amount of air flowing through the sinuses and allow mucous to drain appropriately out of the nose.
Relieve nose blockagesRelieve facial painImprove breathingImprove the olfaction and taste.
SinusitisDeviated septum, when the partition separating the left and also right sides of the nasal is crookedPolyps, a noncancerous water-filled swellingTumors, a swelling caused by an uncontrolled growth of cells.
However, it seems to be less effective regarding those with post-nasal drop or allergies that come from airborne particles that can't be avoided, like dust and ragweed.
To 90% of men and women report a significant reduction in signs and symptoms after endoscopic sinus surgery. Endoscopic sinus surgery has been around

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Retrieved Text: What is acute frontal sinusitis?
Your frontal sinuses are a pair of small, air-filled cavities located just behind your eyes in the brow region. Along with three other pairs of paranasal sinuses, these cavities produce a thin mucus that drains through your nasal passages. Excess mucus production or inflammation of the frontal sinuses can prevent this mucus from draining properly, resulting in a condition called acute frontal sinusitis.
What causes acute frontal sinusitis?
The common cold virus is the most frequent cause of acute frontal sinusitis. When you have a cold or flu virus, it increases the amount of mucus your sinuses produce. That makes them more likely to clog and become inflamed.
Your sinonasal cavity is filled with tiny hairs called cilia that help block organisms from entering the sinuses. These cilia aren’t 100 percent effective. Bacteria can still enter your nose and travel to the sinus cavities. A bacterial infection in the sinuses will often follow a viral infection, since it’s easier for bacteria to grow in the mucus-rich environment caused by a viral infection such as the common cold. Bacterial infections usually cause the most severe symptoms of acute sinusitis.
Polyps are abnormal growths in your body. Polyps in the frontal sinuses may block the sinuses from filtering air and increase the amount of mucus buildup.
People who have a deviated nasal septum can’t breathe equally through both sides of their nose. A lack of proper air circulation can cause inflammation if the tissues of the frontal sinuses become compromised.
Who is at risk for acute frontal sinusitis?
What are the

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Retrieved Text: Many of them are harmful to human health, causing numerous diseases.
The common cold doesn't cause the symptoms of sinusitis but can inflame the paranasal sinuses and when that swelling involves the mucous membranes, the air and mucus are trapped... From there, we have the conditions for the bacteria multiplication, which, with the invasion of the paranasal sinuses, will cause acute sinusitis!
Bacteria can be found in the air of all the environments, but the air from indoor environments, such as our homes, can be up to 90% more polluted than the outdoor air.
AIRFREE® air purifiers are up to 99% efficient by destroying mold spores in the air, bacteria, viruses, ozone, allergens from dust and dust mites and other air pollutants, therefore representing a great ally in improving allergy sufferers’ quality of life.

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Retrieved Text: of the nasal cavity and paranasal sinuses, fluids within these cavities, and/or the underlying bone.
All of these lead to sinus outflow obstruction (either anatomical or functional).
Best imaging modality is CT (coronal and axial) to demonstrate mucosal thickening, polyps, fluid levels in sinuses, as well as underlying anatomical abnormalities predisposing to sinusitis. plain sinus films may show opacification or air-fluid levels, but can appear normal in true sinusitis.
Stimulates alpha-adrenergic receptors in nasal mucosa which vasoconstricts and shrinks swollen mucosa.

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Retrieved Text: Sinusitis is the inflammation of the mucus lining inside of the sinuses. Under normal circumstances, the sinuses are full of air. However, when you are congested your sinus cavity fills with fluid. The fluid may trap pathogens such as viruses, bacteria and fungi, and the pathogens proliferate and may lead to infection. Sinusitis sufferers in Tampa, Spring Hill and surrounding areas in Florida rely on the skill and expertise of the board-certified Otolaryngologist/Head and Neck Surgeons of Suncoast Surgical Specialists for effective treatment of sinusitis.
Acute: The sudden appearance of common cold symptoms such as facial pain, nasal congestion and excessive mucus that fails to resolve within 10 to 14 days. This form of sinusitis usually goes away in less than four weeks.
Sub-acute: Sinus inflammation that lasts between four to eight weeks.
Chronic: Sinus inflammation and associated symptoms that persist for more than eight weeks.
Recurrent: Numerous instances of sinusitis throughout the year.
Health problems or medications that suppress immunity can also lead to an increased risk of sinusitis. For children, sinusitis is usually the result of communicable illness, drinking while lying down, using pacifiers, environmental smoke, and allergies.
You may be diagnosed with acute sinusitis if you’ve had two or more of the above symptoms or have experienced a discharge of thick yellow or green mucus.
Your Suncoast ENT will consider your symptoms and perform a physical exam to determine whether you have sinusitis. The examination can consist of palpating the sinuses to look for tenderness. You may also have your teeth gently tapped on to find out whether an inflamed

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Retrieved Text: To answer that question, we must first look into what the sinuses are. They are actually hollow cavities within the skull, surrounding the nose. Each of us has four sinuses: the frontal sinuses over the eyes in the brow area, maxillary sinuses inside each cheekbone, ethmoid sinuses just behind the bridge of the nose and between the eyes, and sphenoid sinuses behind the ethmoids in the upper region of the nose and behind the eyes.
The good news is that bad breath side effect of sinusitis may be treated by simply treating the sinusitis itself. And there are dozens of different over the counter nasal decongestants and antihistamines that will more than do their job of stopping sinusitis. These drugs act by relieving congestion and drying up excess mucus. However, in doing this, some of these drugs may also inadvertently cause bad breath side effect since dryness in the mouth is one of the most frequent causes of bad breath.

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Input Text: Answer the following question given this paragraph: 

During asexual reproduction, fungi produce haploid spores by mitosis of a haploid parent cell. A haploid cell has just one of each pair of chromosomes. The haploid spores are genetically identical to the parent cell. Spores may be spread by moving water, wind, or other organisms. Wherever the spores land, they will develop into new hyphae only when conditions are suitable for growth.


Q: During asexual reproduction, fungi produce haploid spores by what process involving a haploid parent cell?

 Choices:

- evaporation

- osmosis

- mitosis

- divergence

A:

Target Text: mitosis

#### Retrieved Documents ####

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Retrieved Text: Asexually reproducing organism can cope with a changing environment only through relatively rare spontaneous mutations that prove to be beneficial.
This process does not allow any variation in their population, though it is opposite in the case of sexual reproduction, which accepts variations in their population.
These offsprings are parents again give rise to new one.
No fertilization occurs during asexual reproduction. And due to which sexual reproduction is considered as the most fundamental aspect of evolution. These offspring are usually referred to as clones . Time is taken to complete Multiplication is very rapid and in lesser time. Starfish Regenerating its Legs Agamogenesis Any form of reproduction which does not involve male gametes is known as agamogenesis.
What is asexual reproduction? Types of asexual reproduction There are several different types of asexual reproduction but the most common ones include binary fission, budding, fragmentation and spores.
The number of offspring may vary from two to many and are genetically similar in asexual reproduction whereas the number of offspring produced are less in number comparatively which are genetically different from their parents.
There are specialized organs present in male and female gametes for sexual reproduction in plant and animals. If it continues to grow normally it can eventually become a baby. This combination of gametes is named treatment.
Both of these forms of reproduction occur in plants, fungi and animals however the specific form of reproduction will depend on the species . Puffballs Emitting Spores Sexual Reproduction of Plants Bryophytes like liverworts, mosses, and hornworts consist of motile sperms with flagella.
Fertilization takes place in

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Retrieved Text: Plants are multicellular organisms in the kingdom Plantae that use photosynthesis to make their own food. There are over 300,000 species of plants; common examples of plants include grasses, trees, and shrubs. Plants have an important role in the world’s ecosystems. They produce most of the world’s oxygen, and are important in the food chain, as many organisms eat plants or eat organisms which eat plants. The study of plants is called botany.
Plants are autotrophs; they produce their own food. They do so via photosynthesis, which is the process of making nutrients such as sugars from light energy and carbon dioxide. Photosynthesis occurs in cell organelles called chloroplasts, which contain chlorophyll and carotenoids, molecules that absorb light energy and change it into a usable form. Heterotrophs, on the other hand, are organisms that cannot make their own food and must eat other organisms to survive. Many heterotrophs eat plants. Other heterotrophs eat animals that have eaten plants. Plants are primary producers in many ecosystems, giving them a vital role in the survival of many other organisms. In addition, oxygen is a byproduct of photosynthesis, and many organisms depend on oxygen to survive. We couldn’t live without plants.
Plants are multicellular organisms with eukaryotic cells. A eukaryotic cell is a relatively large cell with a true nucleus and other organelles that perform specific functions. Plants, protists, fungi, and animals all have eukaryotic cells. Plant cells are distinguished by their cell walls containing cellulose, chloroplasts that perform photosynthesis, and a large central vacuole that holds water and keeps the

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Retrieved Text: Young to old. A life cycle?
Not in the biological sense. Life cycles describe the amount of DNA present at a specific stage or time in the life of an organism. Is there a haploid or diploid amount of DNA? That is the key question.
Sexual reproduction occurs in a cycle. Diploid parents produce haploid gametes that unite and develop into diploid adults, which repeat the cycle. This series of life stages and events that a sexually reproducing organism goes through is called its life cycle. Sexually reproducing organisms can have different types of life cycles. Three are represented in Figure below and described following sections.
Life cycles can vary in sexually reproducing organisms. Three types of sexual life cycles are shown here. Do you see how they differ? The letter n indicates haploid stages of the life cycles, and 2n indicates diploid stages.
The haploid life cycle is the simplest life cycle. It is found in many single-celled eukaryotic organisms. Organisms with a haploid life cycle spend the majority of their lives as haploid gametes. When the haploid gametes fuse, they form a diploid zygote. It quickly undergoes meiosis to produce more haploid gametes that repeat the life cycle.
Plants, algae, and some protists have a life cycle that alternates between diploid and haploid phases, known as alternation of generations. In plants, the life cycle alternates between the diploid sporophyte and haploid gametophyte. Spore forming cells in the diploid sporophyte undergo meiosis to produce spores, a haploid reproductive cell. Spores can develop into an adult without fusing with another cell.

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Retrieved Text: Check new design of our homepage! Reproduction is one of the distinguishing features of living organisms, and is essential for the survival of any species. Such perpetuation of species is achieved through two fundamental Reproduce asexually - sexual and asexual. Sexual reproduction involves the formation of a zygote, through the fusion of gametes from two parents.
The zygote develops into an embryo, and grows into an offspring. On the other hand, asexual reproduction involves Reproduce asexually formation of a genetically identical offspring from a single individual. The primitive life forms predominantly exhibit asexual reproduction. The ability to exist in two genders evolved with the changing environment. With the increase in complexity of the newly evolved life forms, the dominance of asexual reproduction decreased.
Nevertheless, each kingdom encompasses a set of strictly asexual organisms, as well as a set of organisms characterized by the presence of both sexual and asexual phases. What is Asexual Reproduction? Asexual reproduction is a reproductive process devoid of gamete formation and fertilization, and mostly proceeds via mitosis. The resultant offspring is a clone of the parent organism due to Reproduce asexually absence Reproduce asexually genetic exchange.
Budding, fission, fragmentation, vegetative propagation, etc. Such reproductive cycles complete in less time, as compared to sexual reproduction, which serves as an evolutionary advantage. However, owing to the lack of genetic variation, the ability to adapt to changing environment is limited.
In asexual organisms, genetic Reproduce asexually can Reproduce asexually only through random mutations. Being so, they are dependent on favorable mutations to cope with environmental changes. List of Organisms

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Retrieved Text: Download "Rhizarians. Forams. Radiolarians. Cercozoans"
14 Figure 29.3 Exploring Derived Traits of Plants Charophyte algae lack the key traits of plants described in this figure: alternation of generations; multicellular, dependent embryos; walled spores produced in sporangia; multicellular gametangia; and apical meristems. This suggests that these traits were absent in the ancestor common to plants and charophytes but instead evolved as derived traits of plants. Not every plant exhibits all of these traits; certain lineages of plants have lost some traits over time. Alternation of Generations The life cycles of all plants alternate between two generations of distinct multicellular organisms: gametophytes and sporophytes. As shown in the diagram below (using a fern as an example), each generation gives rise to the other, a process that is called alternation of generations. This type of reproductive cycle evolved in various groups of algae but does not occur in the charophytes, the algae most closely related to plants. Take care not to confuse the alternation of generations in plants with the haploid and diploid stages in the life cycles of other sexually reproducing organisms (see Figure 13.6). Alternation of generations is distinguished by the fact that the life cycle Mitosis n Alternation of generations: five generalized steps 5 The spores develop into multicellular haploid gametophytes. n MEIOSIS 1 The gametophyte produces haploid gametes by mitosis. Gametophyte (n) Spore includes both multicellular haploid organisms and multicellular diploid organisms. The multicellular haploid gametophyte ( gamete-producing plant ) is named for its production by mitosis of haploid gametes eggs and sperm that fuse during

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Retrieved Text: In this internet lesson, you will review the steps of meiosis and view video simulations of this type of cell division. You will also view an onion root tip and calculate the percentage of cells at each of the stages of cell division.
1. Give an example of asexual reproduction.
2. What is a clone?
3. (Click the next button) What is the difference between haploid and diploid?
4. What is the diploid chromosome number for humans?
13. Name 2 errors that can occur during meiosis.
Test Yourself - Try some of the problem sets on the test yourself pages.

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Retrieved Text: The ability of the living organisms to produce new living beings similar to themselevs is called reproduction.
Single organism commonly multiply through asexual reproduction. Asexual reproduction is the process of formation of new individuals from specialised or unspecialised parts of a single parent without the formation and fusion of gametes. Because of the formation of new individuals from a parent, asexual reproduction is called uniparental.
It is a mode of asexual of asexual reproduction in which a parent undergoes division to form two or more individuals. Fission is of two types, binary fission and multiple fission.
It means ‘splitting into two’. In binary fission, the nucleus or nuclear matter elongates and then divides into two. It is followed by cleavage of cytoplasm in between the two daughter nuclei to form two daughter individuals.
In multiple fission, many individuals are formed from a single individual.
The nucleus of cell divides repeatedly, producing many nuclei.
Each nucleus is surrounded by a small amount of cytoplasm & many daughter cells are produced within the cyst.
The cyst breaks up under favourable conditions & small off springs are liberated.
In plant, multiple fission is seen in many algae & in animals, a common example of multiple fission is that of the malarial parasite (Plasmodium).
In budding a small part of the body of the parent organism grows out as a ”bud” which then detaches and become new organism.
The nucleus of the parent divides and one of the daughter nuclei passes into the bud.
The bud detaches itself from the parent body & becomes a new individual after growing to full

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Retrieved Text: This set contains 67 questions on plant reproduction, anatomy and physiology as well as plant evolution.
A) formation of motile male gametes.
B) alternation of sporophyte and gametophyte generations.
C) presence of both haploid and diploid stages.
Which of the following is NOT a characteristic of plants?
A) Glucose is made from photosynthesis.
B) Cell walls contain cellulose.
D) Diploid and haploid generations alternate in their life cycle.
E) Diploid and haploid phases of their life cycle produce spores.
Cactus plants are adapted to the hot and dry deserts of North and South America. Which of the following characteristics would NOT help cacti to survive the extreme heat and low rainfall?
A) A thick, waxy cuticle.
B) A stem with a small surface area.
C) Stomata that are closed during the day.
D) Thin leaves with a large surface area.
Transport of the products of photosynthesis is understood to occur by pressure flow through the phloem from a source (such as the leaves where the products are produced) to a sink (such as a developing fruit where they are used or stored). Which of the following statements about this transport is FALSE?
A) Water enters the phloem by osmosis.
B) Phloem tubes in a source have a low water pressure.
C) Water and sugar move through the phloem tubes because of pressure.
D) Sugar is removed from phloem by active transport in the sink area.
E) Solutes are pushed along by the flow of water in the phloem.

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Retrieved Text: The life cycle of a fern is complex compared to that of a flowering plant, and the cycle involves both sexual and asexual reproduction. Some ferns are able to produce new plants entirely asexually, but usually a fern's reproductive process includes a sexual stage.
Ferns differ from flowering plants in that they don't reproduce via seeds. Instead, most ferns produce tiny seedlike structures called spores, and when the spores germinate, they grow into new plants that begin the next stage in the life cycle. In flowering plants, seeds are produced sexually, which means they contain a mixture of genetic material from distinct sperm and egg cells that may come from different plants. Fern spores, however, are produced asexually, which means their genetic material is identical to that of the parent fern.
This asexual stage, though, is only the first step in a fern's life cycle. The next step involves sexual reproduction.
Fern spores are dispersed by wind or water, and when they land in a place with the right growing conditions, which typically involves plenty of moisture and shelter from direct sunlight, the spores germinate and grow into tiny plants called gametophytes. Most ferns' gametophytes are very small compared to the size of the parent plants, and they may go entirely unnoticed as they develop.
Gametophytes develop sexual organs and produce sperm and egg cells. One gametophyte's egg cell may be fertilized by a sperm cell from a nearby gametophyte, or the little plant may fertilize itself. Even if the egg is self-fertilized, however, the new plant that grows from

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Retrieved Text: Fungi are one of the five kingdoms of organisms. Like higher plants (of the kingdom Plantae), most fungi are attached to the substrate they grow on. Unlike plants, fungi do not have chlorophyll and are not photosynthetic. Another key difference from plants is that fungi have cell walls composed of chitin, a nitrogen containing carbohydrate. All fungi have nuclei and the nuclei of most species are haploid at most times. Many species have two or more haploid nuclei per cell during most of the life cycle. All fungi reproduce asexually by spore production. Most species reproduce sexually as well.

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Retrieved Text: Shop Top Branded Grow Plant Kit Online. Get Up to 70% Off!
Find Grow Plant At Target™. Buy Online & Pickup In-Store!
The third type of plant reproduction is the spore. The plants use sexual reproduction with the haploid cell of one plant, and the haploid egg of another plant. This makes the sporophyte cell, which feeds off of the parent plant until it is grown enough to support its own life cycle.
In order for the plant to grow, the seed cracks open and the plant begins to sprout out of it. This is called germination and is the next step in the life cycle. We draw this step in the diagram in our notebooks. The plant continues to grow until it is mature enough to produce flowers which is where reproduction occurs.
Plants that reproduce via a seed do so in a process called germination. The embryo waits inside the seed (some plant embryos can wait for decades) until outside conditions begin to break down the seed's outer shell or testa A seed needs water and heat to germinate.Water assists the seed in breaking the seed coat, which in some cases can be very tough.
Start studying science fusion Unit 4 lesson 3: how do plants grow and reproduce. Learn vocabulary, terms, and more with flashcards, games, and other study tools.
How Plants Grow and Reproduce - Chapter Summary and Learning Objectives. Plant growth and reproduction processes can vary widely by the type of plant.

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Retrieved Text: Individual organisms come and go, but, to a certain extent, organisms transcend time through producing offspring. Reproduction in animals occurs in two primary ways: through sexual reproduction and through asexual reproduction.
Now let's take a look at sexual reproduction.
In sexual reproduction, two individuals produce offspring that have genetic characteristics from both parents. Sexual reproduction introduces new gene combinations in a population.
In animals, sexual reproduction encompasses the fusion of two distinct gametes to form a zygote. Gametes are produced by a type of cell division called meiosis.
The gametes are haploid (containing only one set of chromosomes) while the zygote is diploid (containing two sets of chromosomes).
In most cases, the male gamete, called the spermatozoan, is relatively motile and usually has a flagellum. On the other hand, the female gamete, called the ovum, is nonmotile and relatively large in comparison to the male gamete.
There are two mechanisms by which fertilization can take place.
The first is external (the eggs are fertilized outside of the body); the second is internal (the eggs are fertilized within the female reproductive tract).
For example, many animals have estrous cycles that occur during certain parts of the year so that offspring can typically be born under favorable conditions. Humans however, do not undergo estrous cycles but menstrual cycles.

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Retrieved Text: You covered the issue of sexual vs. asexual reproduction, but an interesting question that wasn’t addressed is “Why are there males?” I understand the benefits of gene-sharing, conferred by sexual reproduction, but why does this require sexual dimorphism? One can easily imagine a system where two individuals can share genes without having to be of different sexes. Ursula K. Le Guin envisioned one such possibility in her 1969 novel The Left Hand of Darkness, where individuals can change gender, but especially if we don’t restrict ourselves to viviparous reproduction, why does there even have to be gender? Why does one partner have to contribute the “egg”, and the other the “sperm”? Why not have two equivalent (non-gendered) haploid cells which combine to form a merged offspring (and, speaking of haploid cells, it took me a while to figure out that the word you were tossing around was “ploidy”; a mention of the words “haploid” and “diploid” in the explanation would have helped.)? This ought to double your chances of finding a mate.

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Retrieved Text: Asexual reproduction is a type of reproduction in some organisms in which offspring arise from only one parent. It is the primary form of reproduction in single-celled organisms, however, some plants and fungi can reproduce asexually as well.
There are many advantages of asexual reproduction. One advantage is the speed of producing offsprings quickly. Because it does not involve the formation of gametes so the time is saved and can be utilized by parent cell to spread its genetic material rapidly. It is also beneficial for smaller populations. For example, if there is a small number of plants in an area then, there will be very small amount of plants to pollinate one another. In that case, it will be a good choice to reproduce asexually, to increase the number of plants of that species in such area.
Moreover, if an organism is very successful and its environment is stable i.e. not changing a lot then it will be beneficial to reproduce asexually to get successful offsprings as well.
Although asexual reproduction is advantageous in many cases but sometimes it may cause serious threats to a population. Asexually reproduced offsprings have no diversity. Since they are produced from the single parent so no mix-up of genetic material and no diversity, they are exactly identical. They are very prone to extinction because all the offsprings have same traits so same weaknesses. One diseased organism can cause the whole population to wipe out because there is no genetic diversity. Another disadvantage is the lack of adaptability. If an individual establishes reaction

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Retrieved Text: Meiosis is a reduction division involving one diploid parent cell dividing to produce four haploid daughter cells, i.e. each daughter cell has half the number of chromosomes of the parent cell.
Meiosis then consists of two cell divisions, known as meiosis I and meiosis II. In the first division, which consists of different phases, the duplicated DNA is separated into daughter cells . In the next division, which immediately follows the first, the two alleles of each gene are separated into individual cells.
about the process of meiosis that requires both an understanding of meiosis, and also of how pop beads are used in lab to represent chromosomes in the various stages of meiosis.

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Retrieved Text: 1. the process of reproduction.
2. a class composed of all individuals removed by the same number of successive ancestors from a common predecessor, or occupying positions on the same level in a genealogical (pedigree) chart.
alternate generation reproduction by alternate asexual and sexual means in an animal or plant species.
asexual generation (direct generation) production of a new organism not originating from union of gametes.
first filial generation the first-generation offspring of two parents; symbol F1.
parental generation the generation with which a particular genetic study is begun; symbol P1.
second filial generation all of the offspring produced by two individuals of the first filial generation; symbol F2.
sexual generation production of a new organism from the cell formed by the union of a male gamete (spermatozoon) and a female gamete (oocyte).
spontaneous generation the discredited concept of continuous generation of living organisms from nonliving matter.
reproduction by fission, gemmation, or in any other way without union of the male and female cell, or conjugation.
Reproduction by fission, gemmation, or in any other way without union of the male and female cells, or conjugation.
Synonym(s): heterogenesis (2) , nonsexual generation.
2. a class composed of all individuals removed by the same number of successive ancestors from a common predecessor, or occupying positions on the same level in a genealogical (pedigree) chart. Said also of antibiotics or other chemicals derived from parent compounds.
reproduction by alternate asexual and sexual means in an animal or plant species.
production of a new organism not originating from union of gametes. Called also direct generation.
the first generation offspring of two parents; symbol F1.
all of

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Retrieved Text: What disadvantage do Sordaria have due to their loss of asexual reproduction, and explain the specific differences between Sordaria's reproduction and that of asexually reproducing organisms.
Can anybody please help me/guide me in the right direction? thanks!
Can you tell us the advantages of asexual reproduction? That would seem a good start.
hmm well with asexual reproduction, if the species is already perfect, it will keep producing a clone of itself. I think that's an advantage. Oh, and since you're producing a large number of the same thing, your species can survive (survival of the fittest).
Plus, you don't need a mate. Think Komodo dragons. One female can start a colony on her own.
Indeed, I suspect hello there is a male.
Once you have identified several advantages of asexual reproduction, are you able to think about the problem differently?
I kinda do but how do sordaria reproduce? I know they only reproduce sexually, but I have a feeling that there is more involved.
Sordaria are a fungus, so you would expect them to behave as sexually reproducing fungus do to create another haploid organism.
To really enhance your understanding and application of analytical and critical thought, reverse the question: What advantages are there to sexual reproduction to asexual reproduction?

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Retrieved Text: Spirogyra is one of the commonest and large genus with about 300 species growing as free-floating masses in stagnant or slowly moving waters (streams). Some species, e. g., Spirogyra adnata are attached to the substratum through a basal rhizoidal cell. The masses of plants are slimy to touch because the filaments are surrounded by pectic sheaths which when come in contact water forms mucilage, therefore it is known as water-silk or pond-scum. The spirogyra grows abundantly in spring.
Spirogyra is unbranched with cylindrical cells connected end to end in long green Filaments. The individual cell is cylindrical, much longer than broad. In free-floating species, there is no distinction between the basal and distal ends, whereas in attached forms the lowermost cell develops a rhizoidal outgrowth called holdfast which helps in attachment.
Each has a well-developed cell wall. The cell wall has two layers the outer wall is composed of cellulose while the inner wall is of pectin.
The cytoplasm forms a thin lining between the cell wall and the large vacuole. Electron microscope studies show that mitochondria, endoplasmic reticulum, dictyosomes and other cytoplasmic inclusions are also present in the cell. The chromosomes vary from species to species from 5-24.
Each cell has a prominent nucleus in the center, suspended by the thin strands of cytoplasm from the inner part of the cell wall.
Chloroplasts are embedded in the peripheral Cytoplasm and their numbers are variable (as few as one). The chloroplasts are ribbon shaped and spirally resulting in the prominent and characteristic green spiral on each filament chloroplast contains several pyrenoids,

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Retrieved Text: Sometimes less is more. Scientists have created a new kind of human stem cell that has just half a genome. The cells can be turned into any tissue in the human body, despite only containing one set of chromosomes. The discovery will provide a vital tool for developing therapies to treat a range of conditions, including cancer and infertility, and may even shed light on why we reproduce sexually via two parents rather than one.
Most cells in the body contain information in the form of DNA packaged into two sets of chromosomes – one from each parent. They are called diploid cells. Egg and sperm cells are the exception – they are haploid cells with one set of chromosomes. They can’t normally divide by themselves; instead they come together at fertilisation to create diploid cells that eventually form a fetus.
Embryonic stem cells are diploid cells from which all tissues in the body are built. Now, Nissim Benvenisty, director of the Azrieli Center for Stem Cells and Genetic Research at the Hebrew University of Jerusalem, Israel, and his colleagues have generated haploid embryonic stem cells with a single set of chromosomes.
The new embryonic stem cells could potentially be used to create eggs and sperm for infertile couples.
Perhaps the most important aspect of the work though, is its application in genetic screening. Detecting the effect of single genes that mutate in our cells and cause disease is complicated because the second copy of the gene can serve as a healthy backup. Now that we can make haploid versions

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Retrieved Text: Mitosis is the process of cell division that enables organisms to maintain cell populations and grow. All chromosomes duplicate themselves prior to cell division, followed by partitioning of these exact copies into daughter cells. In the image to the right, two sets of chromosomes are going through mitosis.
In contrast, meiosis is a two-part cell division process which results in reproductive cells (eggs and sperm) with one-half the number of chromosomes of the parent cell.
In males, the process results in four equal gametes with one chromosome each (sperm cells—not shown). In females, each ovum is produced by two chromosome divisions, called the first and second meitic divisions, and the parent cell's cytoplasm and organelles end up in one gamete.
When a haploid sperm cell fertilizes a haploid ovum, a diploid zygote is formed, with one set of chromosomes donated from each parent.

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Retrieved Text: Which cartoon shows the correct way for the chromosomes to line up at the metaphase plate during mitosis?
What would happen if one chromosome failed to have microtubules from both poles attach?
One daughter cell would not have a copy of that chromosome.
Diatoms are protists that have rigid glass walls. Based on this you can conclude that they carry out cytokinesis similarly to ______________.
What would happen if a cell were unable to properly condense its chromosomes during prophase?
The chromosomal DNA would be subjected to shearing forces, fragmenting the chromosome.
What would happen if cytokinesis occurred before telophase was completed?
A cell that has just exited the G1 phase of the cell cycle (and will eventually go on to divide) will next enter ___________________.
Chromosomes condense and begin to be visible during _____________.
A number of chemical treatments cause microtubules to fall apart. Colchicine (mitonic inhibitor) is one such drug. What would happen if a dividing cell was treated with colchicine?
What would happen to a cell if it went directly from prophase to anaphase (i.e., it failed to undergo metaphase)?
The daughter cells would probably not get equal numbers of chromosomes.
A chimpanzee bone marrow cell, in prophase of mitosis, contains 48 chromosomes. How many chromatids does it contain?
When do homologous chromosomes pair?
Starting with one cell, how many daughter cells will be formed when meiosis is complete?
Sperm cells and ova can be classified as ______________ cells.
How many pairs of homologous chromosomes are found in human males?
The cellular process by which gametes are formed from specialized nonreproductive cells is ________ .
Crossing over occurs during which stage

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Retrieved Text: A cell or nucleus that may participate in sexual fusion to form a *zygote. It is normally haploid and thus on fusion of two gametes a diploid zygote is formed. In virtually all plants (exceptions are those with a *diplontic life cycle ) meiosis is separated from *gametogenesis by the development of a somatic gametophyte generation (see alternation of generations ). In the primitive algae and fungi the gametes are often naked and *isogamous. In more advanced forms there is a trend through *anisogamy to *oogamy and specialization of the gametes, so that they become better protected and less dependent on water for survival and dispersal. See also sexual reproduction.

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Retrieved Text: Signaling events during male germ cell differentiation: bases and perspectives.
Berruti G. Signaling events during male germ cell differentiation: bases and perspectives. Front Biosci. 1998;3D1097-108.
In all species, reproductive function depends on the ability of the individual to produce functional differentiated gametes. Spermatogenesis is a cyclic process in which diploid spermatogonia differentiate into mature haploid spermatozoa. Thus from a genetic point of view, spermatogenesis can be divided into two phases, namely the diploid and haploid phase. Indeed, this complex differentiation process is still more intriguing since primary spermatocytes, if genetically diploid, are functionally tetraploid, while elongating spermatids, the germ cells undergoing the most dramatic morphological changes, if genetically haploid, become functionally anucleate due to ongoing condensation of chromatin resulting in an inactive nuclear DNA. This multi-step differentiative pathway is dependent on a specific environment provided by the anatomical and cellular relationships that take place in the testis and more specifically within the seminiferous tubules. Already, early anatomists (mind comes to Enrico Sertoli and Gustaf Retzius) were fascinated by the mixed cellular composition of the testis correctly deciphered as a whole of interacting and interdependent cell types despite the fact these belong to two well-established and different cell lineages, i.e, the somatic and germinal line. Since their time (the XIX century) up to-day a conspicuous bulk of experimental work and a relative massive bibliographic documentation have been provided. From this it stands out : a) a sophisticated role played by the cyclic hormonal control elicited by the hypothalamic-pituitary axis; b) the structural membrane specializations of Sertoli-germ cell communications; c)

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Retrieved Text: There are 3 main branches of life: Archaea, Bacteria and Eukarya. In the domain Eukarya there are 7 kingdoms. In the kingdom Fungi, there are organisms that are characterized by their cell walls made of chitin, by being non-motile, by having no chlorophyll, by partaking in extracellular digestion, by being absorptive heterotrophs as well as by being decomposers. This means that they are more related to animals than plants. Fungi are then categorized into two different groups: macroscopic and microscopic. Both yeast as well as molds are classified as microscopic fungi. Mold is a multicellular microorganism that has many branching filaments, unlike yeast. This is why it is so much more complex. Intricate microorganisms comparable to mold are increasingly more difficult to combat as well as prevent. For starters, it spreads through the air with the use of spores. The type of spore produced can, also, change depending on the surrounding environment. Not to mention that mold outbreaks are much more common than bacterial ones. This is because they have a broader range in habitat compared to bacteria. For these reasons, it is important to inform the masses about such a hazardous organism since once it establishes itself, it is very challenging to remove as well as prevent from re-occurrence.
Mold can reproduce both sexually as well as asexually. Sexual spores are created through meiosis whereas mitosis produces asexual ones. These processes are switched in animals; humans are an example of this. Sexual spores contain half the genetic information from each parent. This means that they have

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Retrieved Text: Both mold and yeast belong to Kingdom Fungi. Both are eukaryotes, meaning they have cell nuclei and membrane-bound organelles. Though both belong to the same kingdom and act as a parasite on other organic matter, yet they are different from each other. Let us see how mold differs from yeast!
Mold is a type of fungi which is a eukaryotic, multicellular organism and grows in the form of multicellular thread-like structures called hyphae. The hyphae are collectively called a mycelium. Molds are heterotrophic organisms, meaning they cannot make their own food like plants. So, in order to survive, they must gain nutrients from other organic substances. They have round or oval shape, appear in different colours and can reproduce asexually or sexually.
There are more than 100000 types of mold. Some of the common types are Rhizopus stolonifer which is known as black bread mold; Penicillium which is used to produce the antibiotic, Penicillin. Like animals, mold does not eat its food; it secretes enzymes to break down the food into smaller organic molecules which are absorbed by it. So, they are decomposers of dead organic matter like leaves, plants and wood etc.
Molds often require moisture to grow which they usually get from washing area, cooking, air humidifiers, condensation or leaks from the water pipes etc. Poor ventilation which tends to increase humidity levels also leads to condensation which helps mold grow and reproduce.
Yeast is also a type of fungi which is a eukaryotic, unicellular organism. It looks like a thread or filament and appears white or colorless.

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Rank: 25
Score: 53.374737
Retrieved Text: Why don’t cyanobacteria and bacteria reproduce by mitosis?
Damaged cells of an organism are usually ___ by mitosis.
All the chromosomes in a diploid cell are paired.
How many chromosomes are produced by the first division during meiosis?
Which statement(s) correspond(s) correctly to a mutation?
The kind of cell division associated with an increase in size and weight of an organism is called ___.
Gametes have ___ the chromosome number of the parent cell.
Chromosomes are attached to the ___ during the metaphase of mitosis.
The spindle apparatus disintegrates during the ___ of mitosis.
-Plant cells divide by means of a cell plate.
How does mitosis in animal cells differ from mitosis in higher plant cells?
Occasionally asexual reproduction can cause undesirable proliferation of an organism.
Nearly all plants can be reproduced asexually.
The new plant produced by the technique of layering must remain attached to the stem of the original plant.
A successful scion will produce the product of the rootstock with greater quality.
The technique of asexual reproduction most commonly used in the production of fruit trees is ___.
The vigor of a rootstock is usually ___ than that of the root system produced by the scion.
Asexual reproduction is most common in plants growing in ___ climates.
An elongated, horizontal stem that grows at the surface of the ground or just below it is called a rhizome.
Animals have more mechanisms for asexual reproduction than plants.
The stock is inserted into the scion during grafting.
The most commonly used method of asexual reproduction used in gardening is the cutting.
Root cuttings are more commonly used than stem cuttings.
A ___ is a plant structure with enlarged

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Rank: 26
Score: 53.04731
Retrieved Text: Haploid is the term used when a cell has half the usual number of chromosomes. A normal eukaryote organism is composed of diploid cells, one set of chromosomes from each parent. However, after meiosis, the number of chromosomes in gametes is halved. That is the haploid condition.
In humans, the diploid number of chromosomes is 46 (2x23). The number in haploid cells (sperm and eggs) is 23. Some types of animals are haploid, such as male Hymenoptera (ants, bees and wasps). This is a special genetic system called haplodiploidy.
Some plants and animals are polyploid, with more than two sets of chromosomes. For example, one species of wheat is hexaploid, with six sets of chromosomes, although other species of wheat have only two sets. Because so many organisms are diploid, it can become confusing whether haploid refers to one set of chromosomes or more than one. The special term monoploid can be used; it means one set of chromosomes.
Haploid Facts for Kids. Kiddle Encyclopedia.

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Score: 52.567436
Retrieved Text: Lulú. “El GIF De La Semana: Mitosis En Tiempo Real.” Esceptica, 22 Jan. 2014, esceptica.org/2014/01/19/el-gif-de-la-semana-mitosis-en-tiempo-real/.
Mitosis and Meiosis sound very similar, but while they share some similar concepts they are two different biological terms. What is Mitosis? Mitosis is cell division creating two “daughter” cells. Daughter cells have the same number of chromosomes and the same kind of chromosomes as the parent cell. What is Meiosis? Meiosis is creating four “daughter” cells that have half of the chromosomes as the parent cell.
While Mitosis and Meiosis both create daughter cells they make two different kinds. Mitosis creates diploid cells or cells that have 23 chromosomes. While meiosis makes haploid cells or gametes which are your reproductive cells such as sperm in males and eggs in females.
Mitosis exists in six different stages each stage doing something different inside of the cell undergoing mitosis.
Interphase: This stage is when the cell is only preparing for Mitosis or Meiosis(Interphase happens in both). This is also where a cell spends most of its life.
Prophase: Prophase is the “first” stage where the nuclear membrane and the nucleus disappear, chromosomes condense and the mitotic spindles form.
Metaphase: This stage is when the duplicated chromosomes line up at the center of the cell. Fun fact this is called the metaphase plate.
Anaphase: Anaphase is when the duplicated chromosomes separate into two identical groups and move towards opposite ends of the cell.
Telophase: This is the second to last stage where membranes form around the two groups of chromosomes at different ends to produce the nuclei in the daughter cells.

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Score: 52.548317
Retrieved Text: Sporangia are the specialized spore producing structures found in plants. In Pteridophytes, two types of sporangia are present. The two types of sporangia are (1) Eusporangium and (2) Leptosporangium. This classification is proposed by Goebel in 1881 based on the developmental pattern of sporangia. The spores produced in the Eusporangium are called eusporangiospores and those produced in the Leptosporangium are called leptosporangiospores.
Eusporangium: The sporangium develops from a GROUP of INITIAL cells and such a development is called development.
Leptosporangium: The sporangium develops from a SINGLE INITIAL cell and such a development is called Leptosporangiate development.
The present post describes the Similarities and Differences between a Eusporangium and Leptosporangium.
Ø Both Eusporangia and Leptosporangia are the spore producing structures in vascular plants.
Ø Both are formed on the sporophyll (a specialized leaf) of the diploid sporophytic plant.
Ø Both produce haploid spores after meiosis.
Ø The first division of the initials of both sporangia is periclinal (transverse division).
1 Eusporangium is developed from a group of initial cells. Leptosporangium is developed from a single initial cell.
2 Sporangial initial undergo a periclinal division to form an outer layer and an inner layer of cells. Sporangial initial undergo a periclinal division to form an outer cell and inner cell.
3 The outer layer of cells produces the sporangial wall. The entire components of the sporangium such as stack, sporangial wall, and sporogenous tissue are produced only from the outer cell.
4 The inner layer of cells produces the spore mother cell, which latter undergo meiosis to produce haploid spores. Inner cell does not have any role in the

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Score: 52.331738
Retrieved Text: Most fungi have more than one means of reproducing themselves. The most elaborate method is typically sexual reproduction, which involves the mating of two strains (or often one strain with itself). Sexual reproduction produces recombinative spores called either ascospores, basidiospores of zygospores, according to the division to which the fungus in question belongs (the Ascomycota, Basidiomycota or Zygomycota, respectively). Many fungi may be reproduced more simply than this, however. It is often possible to take a fragment of a hypha or a bit of mycelium from a colony, place it on a nutrient medium and with a little time obtain a new fungus colony. This is usually the preferred method for reproducing fungi in the laboratory. A great number of fungi rely on this simple means of colony fragmentation for reproduction in their natural habitats. In fact, the success of asexual reproduction has driven the evolution of a wide variety of modified hyphae that simply break apart to facilitate dispersal. Asexual reproduction is so successful that some fungal species have simply ceased to undergo sexual reproduction. A similar trend is common in certain plant species which have lost the ability to flower and reproduce themselves by runners, tillers, rhizomes and various kinds of fragmentation. Since the classification of fungi (like plant classification) is based upon the form of the sexual reproductive structures, it has been difficult to integrate fungi which no longer exhibit sexuality into the traditional classification scheme. Thus, a special division called “Deuteromycota” was set up to accommodate these fungi. Unlike the other fungal

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Input Text: Answer the following question given this paragraph: 

transports an amino acid varies. Most carriers are linked to the active transport of sodium. Short chains of two amino acids (dipeptides) or three amino acids (tripeptides) are also transported actively. However, after they enter the absorptive epithelial cells, they are broken down into their amino acids before leaving the cell and entering the capillary blood via diffusion.


Q: Short chains of two amino acids (dipeptides) or three amino acids (tripeptides) are also transported actively. however, after they enter the absorptive epithelial cells, they are broken down into their amino acids before leaving the cell and entering the capillary blood via what?

 Choices:

- osmosis

- diffusion

- absorption

- convection

A:

Target Text: diffusion

#### Retrieved Documents ####

Rank: 0
Score: 93.14382
Retrieved Text: The digestion of protein entails breaking the complex molecule first into peptides, each having a number of amino acids, and second into individual amino acids. The pepsins are enzymes secreted by the stomach in the presence of acid that breaks down proteins (proteolysis). The pepsins account for about 10 to 15 percent of protein digestion. They are most active in the first hour of digestion, and their ability to break down protein is restricted by the necessity for an acidic environment with a pH between 1.8 and 3.5. The trypsins (proteolytic enzymes secreted by the pancreas) are much more powerful than pepsins, so the greater part of protein digestion occurs in the duodenum and upper jejunum. Therefore, even after total removal of the stomach, protein digestion usually is not impaired.
Pancreatic secretion contains inactive protease precursors that become enzymatically active after interacting with another enzyme, enterokinase, which is secreted from the microvillous component of the enterocytes in the duodenal and jejunal mucosa. Trypsinogen is activated in the intestine by enterokinase, which is liberated from duodenal lining cells by the interaction of bile acids and CCK. This activation of trypsinogen to trypsin is initiated by the cleavage from it of six terminal amino acid residues. The other proteases are activated by free trypsin. The net effect of these proteases is to reduce dietary proteins to small polypeptide chains of two to six amino acids and to single amino acids. Trypsin activates the other pancreatic proteases, including chymotrypsin and elastase. Trypsin, chymotrypsin, and elastase are known as endopeptidases and

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Rank: 1
Score: 73.72727
Retrieved Text: We derive structural and binding energy trends for twenty amino acids, their dipeptides, and their interactions with the divalent cations Ca2+, Ba2+, Sr2+, Cd2+, Pb2+, and Hg2+. The underlying data set consists of more than 45,000 first-principles predicted conformers with relative energies up to ∼4 eV (∼400 kJ/mol). We show that only very few distinct backbone structures of isolated amino acids and their dipeptides emerge as lowest-energy conformers. The isolated amino acids predominantly adopt structures that involve an acidic proton shared between the carboxy and amino function. Dipeptides adopt one of two intramolecular-hydrogen bonded conformations C5 or. Upon complexation with a divalent cation, the accessible conformational space shrinks and intramolecular hydrogen bonding is prevented due to strong electrostatic interaction of backbone and side chain functional groups with cations. Clear correlations emerge from the binding energies of the six divalent ions with amino acids and dipeptides. Cd2+ and Hg2+ show the largest binding energies-a potential correlation with their known high acute toxicities. Ca2+ and Pb2+ reveal almost identical binding energies across the entire series of amino acids and dipeptides. This observation validates past indications that ion-mimicry of calcium and lead should play an important role in a toxicological context.

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Rank: 2
Score: 73.21971
Retrieved Text: The American Peptide Symposium is a biennial event organized by the American Peptide Society, a nonprofit scientific and educational organization dedicated to advancing and promoting knowledge of the chemistry and biology of peptides.
This year, the 25th American Peptide Symposium will be held on June 17-22, 2017 in Whistler, BC, Canada.
The symposium theme of New Heights in Peptide Research will cover a broad range of topics connecting chemical, materials, biological, pharmaceutical and medical science.
The American Peptide Symposium provides a forum to learn and share the latest results with professors, students, postdocs, and industrial researchers who make exciting contributions to peptide research.
We invite you to visit us at our Booth #18:please contact us to schedule a meeting in advance.
We look forward to meeting you at APS 2017!
Even though they are the smallest peptides, dipeptides and tripeptides can be biologically active or show specific properties. Or, as digestion products of proteins, function as source of amino acids. Two transporter proteins mediate the cellular uptake for further processing of di- and tripeptides. PepT1 located in the brush border membrane of the intestinal epithelium transfers the nutritional peptides from the small intestinal lumen into intestinal absorptive cells (enterocytes). PepT2 expressed in the renal tubules is involved in their re-adsorption from primitive urine.
400 different dipeptides can be formed when connecting the 20 proteinogenic amino acids and most of them if not all have been detected in nature. This diversity is increased by involving the side chains of Asp, Glu, or Lys in peptide bond formation, modifications as N-terminal acetylation and C-terminal amidation,

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Rank: 3
Score: 70.75685
Retrieved Text: What do you mean by oligo-peptides?
A peptide is a polymer made of amino acids linked between each other by peptidic liaisons.
These oligopeptides can also be classified according to the number of amino acids* : those composed of two amino acids (like aspartame or alitame) they are called dipeptides, and those composed of three amino acids that are called tripeptides. Generally, when they are longer, we simply speak of peptides (we abandon the specification of the number of amino acids). Polymers composed of a larger number of amino acids are simply called polypeptides. They are generally issued from a translation of a messenger RNA. Proteins, finally are assemblies of one or many polypeptides having been submitted to modifications post translation with the result of being the subject of a proteinic folding.
Neuropeptides are peptides that have been secreted by a neuron that singularizes itself by its neuro-transmitter function.
The discovery of the first bioactive peptide is already older than 90 years old. As a matter of fact, in 1923, Banting and Macleod were awarded the Nobel Prize of Medicine for their discovery of Insulin and of one peptide acting on the glycaemia by its action on the pancreas well known in the treatment of diabetes. This peptide molecule had been extracted at the time, from the pancreas of a beef and a pork.
Progresses in peptide extraction permitted the production of highly performing peptides that conducted to the selection of bioactive peptides. Since this technological breakthrough, peptides, on the same basis as proteins, are considered as the natural molecules of

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Rank: 4
Score: 69.46692
Retrieved Text: Of the 22 standard proteinogenic (also known as standard, normal, or primary) amino acids, 20 are directly encoded by the universal genetic code, with selenocysteine and pyrrolysine being incorporated into proteins by unique synthetic mechanisms. 8 are understood to be essential amino acids because the human body is unable to synthesise them from other compounds to meet the dietary requirements for normal growth, so they must be obtained from food.
However, the situation is a little more complicated since cysteine, tyrosine, histidine and arginine are semi-essential amino acids in children, because the metabolic pathways that synthesise these amino acids are not fully developed. The amounts required also depend on the age and health of the individual, so it is hard to make general statements about the dietary requirement for some amino acids.
The amino acids leucine, isoleucine and valine are known as branched-chain amino acids or BCAA’s. It is their chemical make-up that gives them this name, because these amino acids have aliphatic side-chains (A compound composed of carbon and hydrogen arranged in straight or branched chains, and not containing aromatic rings) that are non-linear. These three amino acids are also Essential Amino Acids (EAAs).
The combination of these three essential amino acids make up approximately 1/3 of skeletal muscle in the human body, and play an important role in protein synthesis. As a result, BCAA’s, or protein powders containing them, are very popular with athletes and those undertaking exercise as an aid to muscle recovery.,Unlike other amino acids which, when consumed in free form are absorbed and processed

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Rank: 5
Score: 69.44658
Retrieved Text: Amino acid complex with essential amino acids. 240 tablets each containing 500 mg amino acids.
Amino Vida contains nine high-purity, free and crystalline amino acids from pulses of natural origin, is vegan and free of any additives. It provides an optimal amino acid pattern, has almost no calories and is available to the body after a short time.
Amino Vida contains nine free crystalline amino acids in a perfect combination. The amino acids of highest purity are obtained naturally from pulses, are vegan and additive-free. Amino Vida provides the human body with an optimal amino acid combination and is almost calorie free. It is bio-available to the body shortly after ingestions. Amino Vida is an ideal amino acid nutrition for athletes and people who would like to supplement their bodies essential amino acid supply.
Amino Vida contains all eight essential amino acids as well as the semi-essential amino acid arginine. Essential means, that the amino acids are vital to our well-being and cannot be produced by the body itself. L-arginine is deemed semi-essential as it can be synthesised by the human body. In certain circumstances (e.g., age, growth phases, diseases, or physical activity), L-arginine can also become essential to the body.
Amino acids are the building blocks of proteins. Amino Vida has a high protein content. Proteins contribute to the maintenance and increase of muscle mass.
Amino Vida provides an optimal ratio of all eight essential amino acids (L-Leucine, L-Valine, L-Isoleucine, L-Lysine, L-Phenylalanine, L-Threonine, L-Methionine, L-Tryptophan) for the human nutritional system.
Amino Vida also contains the semi-essential amino acid L-arginine. It is

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Rank: 6
Score: 69.01012
Retrieved Text: The rise of CuI-catalyzed click chemistry has initiated an increased demand for azido and alkyne derivatives of amino acid as precursors for the synthesis of clicked peptides. However, the use of azido and alkyne amino acids in peptide chemistry is complicated by their high cost. For this reason, we investigated the possibility of the in-house preparation of a set of five Fmoc azido amino acids: β-azido l-alanine and d-alanine, γ-azido l-homoalanine, δ-azido l-ornithine and ω-azido l-lysine. We investigated several reaction pathways described in the literature, suggested several improvements and proposed several alternative routes for the synthesis of these compounds in high purity. Here, we demonstrate that multigram quantities of these Fmoc azido amino acids can be prepared within a week or two and at user-friendly costs. We also incorporated these azido amino acids into several model tripeptides, and we observed the formation of a new elimination product of the azido moiety upon conditions of prolonged couplings with 2-(1H-benzotriazol-1-yl)-1,1,3,3-tetramethyluronium hexafluorophosphate/DIPEA. We hope that our detailed synthetic protocols will inspire some peptide chemists to prepare these Fmoc azido acids in their laboratories and will assist them in avoiding the too extensive costs of azidopeptide syntheses.
We demonstrate that multigram quantities of selected Fmoc azido amino acids can be prepared within a week or two and at user-friendly costs.

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Rank: 7
Score: 67.6787
Retrieved Text: Preproinsulin is translated in the beta-cell cytoplasm after which it is cleaved into proinsulin in the ER and then transported to the Golgi apparatus. Proinsulin processing occurs in maturing secretory granules and thus, insulin and C-peptide are secreted simultaneously, in equimolar amounts, in response to various stimuli, including glucose.
Insulin is made up of 51 amino acids and is one of the smallest proteins in the body. It is comprised of two polypeptide chains linked by two disulfide bonds, connecting cysteine molecules. There is a third disulfide bond that connects two amino acids within Chain A. Chain A consists of 21 amino acids and chain B contains 30 amino acids.
The amino acid sequence of insulin is highly conserved among vertebrates. Virtually all primates and monkeys share the same sequence. Rat and mouse insulins only differ from primate insulin by 4 amino acids. Even the positions of the three disulfide bonds are the same for most species. The similarities in amino acid sequences and conserved positions of the disulfide bonds lead to a three dimensional conformation of insulin that is very similar across species. Thus, insulin from one species is often biologically active in other species. For example, pig insulin has historically been used to treat human patients. Insulin from some species of fish can also be similar enough to human insulin to be clinically effective in humans. In addition, insulin in some invertebrates is quite similar to human insulin, and has similar physiological effects.
Unlike insulin, C-peptide structure differs greatly between species. For example, the amino acid sequence

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Rank: 8
Score: 67.1152
Retrieved Text: Proteins are not the same as Lego building blocks, but proteins do have special shapes that can be used to build parts of the body. Johnson Righeira Lego portrait via Wikimedia. Click the image to see full size.
Just like a Lego house is made of bricks, proteins are made up of lots of tiny building blocks. These building blocks are called amino acids.
To build a protein, first the amino acids are connected into long chains. These chains of amino acid building blocks can then fold into all types of shapes. Some chains fold into spirals. Other chains make zigzag sheets, and loops.
Combining these spirals, sheets, and loops is how the three-dimensional shape of the protein is made. You can also combine multiple strands of amino acids to make even bigger protein shapes.
The human body uses just 21 amino acids to make all the proteins it needs to function and grow. Because amino acids can be arranged in many different combinations, it's possible for your body to make thousands of different kinds of proteins from just the same 21 amino acids. You may see books that say there are only 20 amino acids. Don't worry, that's just because the 21st one was discovered pretty recently and not all the books have caught up yet.
21 Amino Acids. Click on the image to see a a larger version.
There are nine amino acids that your body can’t make. They are called essential amino acids, meaning you must have them to live. They are found in foods like milk, eggs and

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Rank: 9
Score: 67.10553
Retrieved Text: "Peptides" redirects here. For the journal, see Peptides (journal).
blue marked carboxyl end (L-Alanine).
Peptides (from Greek language πεπτός, peptós "digested"; derived from πέσσειν, péssein "to digest") are short chains of amino acid monomers linked by peptide (amide) bonds.
The covalent chemical bonds are formed when the carboxyl group of one amino acid reacts with the amino group of another. The shortest peptides are dipeptides, consisting of 2 amino acids joined by a single peptide bond, followed by tripeptides, tetrapeptides, etc. A polypeptide is a long, continuous, and unbranched peptide chain. Hence, peptides fall under the broad chemical classes of biological oligomers and polymers, alongside nucleic acids, oligosaccharides and polysaccharides, etc.
Peptides are distinguished from proteins on the basis of size, and as an arbitrary benchmark can be understood to contain approximately 50 or fewer amino acids. Proteins consist of one or more polypeptides arranged in a biologically functional way, often bound to ligands such as coenzymes and cofactors, or to another protein or other macromolecule (DNA, RNA, etc.), or to complex macromolecular assemblies. Finally, while aspects of the lab techniques applied to peptides versus polypeptides and proteins differ (e.g., the specifics of electrophoresis, chromatography, etc.), the size boundaries that distinguish peptides from polypeptides and proteins are not absolute: long peptides such as amyloid beta have been referred to as proteins, and smaller proteins like insulin have been considered peptides.
Amino acids that have been incorporated into peptides are termed "residues" due to the release of either a hydrogen ion from the amine end or a hydroxyl ion (OH−) from the

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Rank: 10
Score: 67.05596
Retrieved Text: This next section will briefly describe normal protein metabolism and the cellular metabolism of proteins instead of glucose for energy in diabetes. Protein metabolism is very complex; therefore, this section focuses only on topics that are relevant to your understanding of type-2-diabetes.
As noted earlier, when insulin action is normal, glucose is used for energy. However, abnormalities in glucose metabolism in patients with type-2-diabetes lead to problems of meeting the body’s energy needs, and the body (at times) turns to proteins for its fuel source.
Proteins can form the structure of organs and muscles.
Proteins can function as enzymes to facilitate the chemical reactions of metabolism.
Proteins can be broken down for energy production when glucose is not available.
Proteins are synthesized from molecules called amino acids. Much like beads in a necklace, amino acids are linked together in long chains called peptides. Proteins are formed when one or more peptide chains are coiled and folded in configurations specific to each protein.
Following a meal containing proteins (such as meat, fish, chicken, etc.), the proteins are broken down into amino acids in the digestive tract in a process termed proteolysis.
The amino acids are absorbed into the blood. After entering the bloodstream, amino acids are taken up by cells of the entire body, especially the liver.
Within the cells, amino acids are used to synthesize other proteins that cells need.
In the liver, proteins can be broken down later to amino acids that can be used to produce energy or be converted to glucose (Gluconeogenesis).
Insulin affects protein metabolism by promoting protein synthesis and storage and

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Rank: 11
Score: 66.947365
Retrieved Text: Protein is one of the nutrients along with carbohydrate, fat, vitamins, minerals, and water.
Proteins are single, unbranched chains of amino acid monomers. Amino acids are the building blocks of proteins. There are 20 different naturally occurring amino acids. The amino acid side chains in a peptide can become modified, extending the functional repertoire of amino acids to more than hundred different amino acids. A protein’s amino acid sequence determines its three-dimensional structure.
To make a protein, these amino acids are joined together in a polypeptide chain through the formation of a peptide bond.
Chains that are less than 40-50 amino acids or residues are often referred to as polypeptide chains since they are too small to form a functional domain. Larger than this size, they are called proteins.
Humans can synthesize 12 (nutritionally nonessential) of the 20 common amino acids from the amphibolic intermediates of glycolysis and of the citric acid cycle. Of the 12 nutritionally nonessential amino acids, nine are formed from amphibolic intermediates and three (cysteine, tyrosine and hydroxylysine) from nutritionally essential amino acids. Protein is an essential nutrient. There is no life without protein.
Protein is contained in every part of human body, the skin, muscles, hair, blood, body organs, eyes, even fingernails and bone. Next to water, protein is the most plentiful substance in human body.
Protein has a critical physiological function. Protein is primarily used in the body to build, maintain, and repair body tissues. In the event that protein intake is greater than that required by the body for this primary function, excessive protein is

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Rank: 12
Score: 66.84955
Retrieved Text: Let’s face it, as men, nearly all of us dream about sporting a lean six pack, bulging 20 inch biceps and a set of broad shoulders like cannon balls. We strive for perfection yet many of us are simply not aware of all the facts regarding bodybuilding and conditioning, and as a result, we aren’t able to truly get the most out of our workouts. Bodybuilding is about so much more than simply lifting weights in a gym for instance. It’s a way of life and requires a huge amount of hard work and dedication. As well as the training aspects, there are also the nutritional aspects to consider. You can lift all of the weights you like, and train as intensely and as focused as you like, but if your diet isn’t on form, you won’t truly see the same benefits as somebody whose diet was on form. After that, there’s the complicated matter of supplementation. Protein is obviously a bodybuilder’s best friend, due to the fact that it’s essential for the growth and repair of our muscles. But why is it essential? The main reason is because it contains amino acids.
Amino acids are often described as the building blocks of protein and muscle. They’re responsible for cellular growth, strengthening, and repair, making them essential for bodybuilders. When we lift weights, the cells and tissues in our muscles become damaged and destroyed, and need to be repaired and re-built bigger and stronger than they were previously. When the body repairs them, it rebuilds them bigger

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Rank: 13
Score: 66.45398
Retrieved Text: Author(s): M. E. Ganapathy, V. Ganapathy. Department of Medicine, Medical College of Georgia, Augusta, GA 30912, USA.
ATB0,+ is a unique amino acid transporter because of its broad substrate specificity and concentrative ability. This transporter recognizes neutral as well as cationic amino acids. It is energized by Na+ and Cl- gradients and membrane potential. Many of the amino acids and amino acid derivatives that are substrates for ATB0,+ serve as therapeutic agents (e.g., D-serine, carnitine, and nitric oxide synthase inhibitors). Recent studies have shown that the potential of ATB0,+ as a drug delivery system may be greater than previously envisaged. ATB0,+ can transport antiviral drugs such as acyclovir and ganciclovir when they are covalently coupled to the side chain of anionic amino acids. Chemical modification of the carboxyl groups in the side chain of aspartate and glutamate with drugs converts these anionic amino acids into neutral amino acid derivatives. Therefore, the modified drugs are recognized by ATB0,+. Interestingly, even when acyclovir and ganciclovir are coupled as esters with α-carboxyl group of neutral amino acids, the modified drugs are transported via ATB0,+. Similarly, the hydroxyl group in the side chains of serine and threonine can also be used to covalently couple drugs for delivery into cells via ATB0,+. This increases the potential for designing a wide variety of amino acid-based prodrugs that can utilize ATB0,+ as drug delivery system. Furthermore, the transporter is expressed in the colon, lung, and eye, the tissues easily amenable for drug delivery. These findings argue strongly in support of ATB0,+ as a potential

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Rank: 14
Score: 65.87854
Retrieved Text: Alanine, arginine, asparagine, aspartic acid, branched amino acid therapy, controlled amino acid therapy, CAAT, cysteine, diet, Dk, functional foods, glutamic acid, glutamine, glycine, histidine, isoleucine, leucine, lysine, methionine, Nilab, phenylalanine, PreKUnil, proline, serine, tryptophan, tyrosine, valine.
Amino acid therapy presumes that many symptoms and illnesses occur because the body is unable to manufacture the proper amino acid. By supplementing the body's normal supply of amino acids (amino acid therapy), symptoms and illnesses may be resolved. Many patients turn to amino acid therapy from the belief that their body is not manufacturing enough amino acids and therefore, bodily processes are not functioning correctly.
Amino acids are the building blocks from which the body creates the proteins necessary for life. Amino acids link together to form peptides (short chains), which then form larger structures called proteins. There are 20 standard amino acids in the genetic code. Combinations of these amino acids produce every essential protein needed for the human body's homeostasis (healthy balance). Most bodily processes cannot occur without amino acids because they require the proper protein to function.
Some healthcare professionals may recommend taking only the eight essential amino acids or the three branched chain amino acids depending on the treated condition. Amino acids have been used in clinical tests to treat a variety of serious illnesses and conditions including: phenylketonuria (PKU, a disorder of the metabolism), epilepsy, congenital microcephaly (birth defect), hepatitis complications, spinocerebellar degeneration, hemodialysis, lateral sclerosis, peritoneal dialysis, chronic pain, parenteral nutrition, liver cancer, muscular dystrophy and hypertrophy of the prostate. The scientific community has also published

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Rank: 15
Score: 65.86785
Retrieved Text: Amino acids are the building blocks of polypeptides and proteins, which are used as structural components and enzymes. If you’re taking biochemistry, organic chemistry, or genetics, you need to be familiar with the 20 amino acids and also know their side chains. It’s the nature of the side chains that determines how a protein folds into its structure and how it functions.
Non-Polar Hydrophobic: The non-polar hydrophobic amino acids lack side chain polarity. They tend not to interact with water molecules. These amino acids are glycine, alanine, valine, leucine, isoleucine, methionine, phenylalanine, tryptophan, and proline.
Polar Hydrophobic: Even though these amino acids are polar, they only weakly interact with water. Polar hydrophobic amino acids are either weakly hydrophobic or else the configuration of the side chain prohibits interaction with water. These amino acids are cysteine and tyrosine.
Polar Hydrophilic: These amino acids are water-loving because of electronegativity differences between atoms in the side chains (e.g., N and O). Their presence causes a polypeptide chain to twist toward water, while a hydrophobic chain causes a twist away from water. The polar hydrophilic amino acids are serine, threonine, asparagine, and glutamine.
Acidic: If there is a carboxylic acid in a side chain, you get an acidic side chain. If the NH2 group is swapped for an OH group, you can an acidic carboxyl group. Amino acids with acidic side groups are aspartic acid/aspartate, acetic acid/acetate, and glutamic acid/glutamate.
Basic: If it’s an amino “acid,” then how can it be basic? Basic amino acids have a nitrogen atom that has a lone electron pair

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Retrieved Text: - Proteins that have many alpha helical structures are alpha keratin Hemoglobin, myoglobin. - Beta pleated sheets are the gfp second regular secondary structure contain in proteins. Correlation of these sequences structures revealed that some amino acids are found more often in alpha helices, , beta sheets neither. Alpha Helix and helices Beta- pleated sheet. 54 nm and in each turn there are 3. Pitch of the helix is 0. The β sheet ( also β- pleated sheet) is the does second form of regular secondary structure in proteins, only somewhat does less common than alpha helix. Complete proteins are those that contains all the essential amino acids. Parallel sheets form contain when the two chains are gfp aligned in the same direction from the amino to carboxyl end contain antiparallel sheets form when the two chains have opposing polarities.
Beta pleated sheet. Different amino acids does favor the formation gfp of alpha helices , and beta pleated sheets loops. Alpha Helix: Alpha helix prefers the amino acid side chains which does can cover protect the backbone H- bonds in the core of the helix. and Alpha helices always have a right handed curl. just a fun fact I guess. Beta gfp Pleated Sheet: The extended structure leaves the maximum space free for the amino acid side chains. - Vertical does distance occupied by each amino acid is 0.
3Secondary Structure: Polypeptide Chains Can Fold Into Regular Structures Such as the Alpha Helix Turns , , the Beta Sheet Loops. These two structural components does are the first

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Retrieved Text: A substitution is more likely to occur between amino acids with similar biochemical properties. For example the hydrophobic amino acids Isoleucine(I) and valine(V) are more likely to substitute for one another than the hydrophilic amino acid cystine would with one of these. Amino acids come in the following types.
The hydrophobic side chains of these amino acids will not form hydrogen bonds or ionic bonds with other groups. These hydrophobic amino acids tend to be buried in the centre of proteins away from the surrounding aqueous environment.
Ala, Val, Leu, lle, Met, Pro, Phe, Trp.
The side chains of these amino acids are uncharged at physiological pH.
Ser, Tyr, Asp, Gln, Cys.
These have a carboxylic acid group in their side chain and are very hydrophilic.
The single hydrogen atom side chain has no strong hydrophobic or hydrophilic properties.
Nucleotide bases fall into two categories depending on the ring structure of the base. Purines (Adenine and Guanine) are two ring bases, pyrimidines (Cytosine and Thymine) are single ring bases. Mutations in DNA are changes in which one base is replaced by another. A mutation that conserves the ring number is called a transition (e.g., A -> G or C -> T) a mutation that changes the ring number are called transversions. (e.g. A -> C or A -> T and so on).
The genetic code in the table above has also been called "The Universal Genetic Code". It is known as "universal", because it is used by all known organisms as a code for DNA, mRNA, and tRNA. The universality of the genetic code

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Retrieved Text: Wipf, Peter; Heimgartner, Heinz (1987). Selektive Amidspaltung bei Peptiden mit alpha,alpha-disubstituierten alpha-Aminosäuren. Helvetica Chimica Acta, 70:354-368.
A new synthesis of dipeptides with terminal alpha,alpha-disubstituted alpha-amino acids, using 2,2-disubstituted 3-amino-2H-azirines 1 as amino-acid equivalents, is demonstrated. The reaction of 1 with N-protected amino acids leads to the corresponding dipeptide amides in excellent yield. It is shown that the previously described selective hydrolysis (HCl, toluene, 80°, or HCI, MeCN/H2O, 80°) of the terminal amide group results in an extensive epimerization of the second last amino acid. An acid-catalyzed enolization in the intermediate oxazole-5(4H)-ones is responsible for this loss of configurational integrity. In the present paper, a selective hydrolysis of the terminal amide group under very mild conditions is described: In 3N HCI (THF/H2O 1:1), the dipeptide N,N-dimethylamides or N-methylanilides are hydrolized at 25-35° to the optically pure dipeptides in very good yield.
Download PDF 'Selektive Amidspaltung bei Peptiden mit alpha,alpha-disubstituierten alpha-Aminosäuren'. Item availability may be restricted.

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Retrieved Text: ​L-Ornithine alpha-ketoglutarate (OKG) is a substance, formed of the molecules of two amino acids - ornithine and glutamine. ​​In a conjugated form, OKG can be found only as a specialized dietary supplement.
​Its Individual components ornithine and glutamine are widely spread as part of the structure of protein chains in various foods.
​Besides the anti-catabolic functions that stop the release of cortisol, OKG is is famous for its anabolic effect in correlation with the processes of building new muscle fibers.
​While no one knows the exact mechanism of foreclosure of cortisol secretion after intake of OKG, statistics of reported studies suggest the probable blocking of enzymes that unlock the cortisol response at a cellular level.
If you want to stop the catabolic breakdown of your muscles during long aerobic workouts in the process of losing weight, you can always take advantage of its proven anticatabolic reputation.
What are the benefits of the name of this little-known substance, a derivative of the otherwise known ornithine and glutamine amino acids? There is evidence that it is a serious anticatabolic - a substance protecting us from stress.
​While no one knows the exact mechanism of obstruction of cortisol secretion after intake of OKG, the statistics in the studies suggests that this is probably due to the blocking of enzymes that unlock the cortisol response of cells.
Ornithine alpha-ketoglutarate (OKG) is a substance, formed of the molecules of two amino acids - ornithine and glutamine.
Anticatabolic, probably anabolic. It has been found that the amount in the blood and cell plasma is in inverse proportion to the quantities

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Retrieved Text: 1. Humans must ingest proteins, carbohydrates and lipids to maintain tissue and organ function.
2. Most of these nutrients consist of large polymers that must be broken down before they can be made available to the intestinal cells for transport.
3. Dietary proteins are cleaved by hydrolases with specificity for the peptide bond (peptidases).
4. Endopeptidases (aka Proteases): attack internal protein bonds liberating large peptide fragments.
NH3+, aminopeptidases or COO- terminus, carboxypeptidase.
1. Gastric HCl is responsible for the low pH <2 of gastric juice.
2. Gastric acid kills microorganisms and denatures dietary proteins preparing them for hydrolysis by proteases.
3. Gastric juices contain the acid stable proteases of the pepsin family, which produce large peptide fragments and some free amino acids.
4. Protein digestion at this stage is partial, as the amino acids and small proteins enter the duodenum, they trigger the release of cholectystokinin-pancreozymin (CCK-PZ) into the bloodstream.
This release initiates the secretion of protease zymogens from the pancreas and release of enteropeptidase in the gut.
1. The pancreatic juice is rich in the proenzymes of endopeptidase and the carboxypeptidases.
2. Enteropeptidase converts pancreatic trypsinogen to trypsin.
3. Trypsin autocatalytically activates more trypsinogen and other proenzymes, liberating chymotrypsin, elastase and the carboxypeptidases A and B.
1. Since pancreatic juice does not contain appreciable aminopeptidase activity, final digestion of di- and small peptides depends on brush border enzymes.
2. The surface of intestinal epithelial cells is rich in endopeptidases and aminopeptidases.
3. The end products of cell surface digestion are free amino acids and di- and tripeptides.
1. Following digestion, amino acids and small peptides are co-absorbed w/ sodium via group

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Retrieved Text: Insulin, hormone that regulates the level of sugar (glucose) in the blood and that is produced by the beta cells of the islets of Langerhans in the pancreas. Insulin is secreted when the level of blood glucose rises—as after a meal. When the level of blood glucose falls, secretion of insulin stops, and the liver releases glucose into the blood. Insulin was first reported in pancreatic extracts in 1921, having been identified by Canadian scientists Frederick G. Banting and Charles H. Best and by Romanian physiologist Nicolas C. Paulescu, who was working independently and called the substance “pancrein.” After Banting and Best isolated insulin, they began work to obtain a purified extract, which they accomplished with the help of Scottish physiologist J.J.R. Macleod and Canadian chemist James B. Collip. Banting and Macleod shared the 1923 Nobel Prize for Physiology or Medicine for their work.
Insulin is a protein composed of two chains, an A chain (with 21 amino acids) and a B chain (with 30 amino acids), which are linked together by sulfur atoms. Insulin is derived from a 74-amino-acid prohormone molecule called proinsulin. Proinsulin is relatively inactive, and under normal conditions only a small amount of it is secreted. In the endoplasmic reticulum of beta cells the proinsulin molecule is cleaved in two places, yielding the A and B chains of insulin and an intervening, biologically inactive C peptide. The A and B chains become linked together by two sulfur-sulfur (disulfide) bonds. Proinsulin, insulin, and C peptide are stored in granules in the beta cells, from

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Retrieved Text: Proteins are necessary for building the structural components of the human body, such as muscles and organs. You also need proteins to keep your immune system healthy, synthesize neurotransmitters, create and signal hormones, and much more. A balanced diet supplies you will all of the protein you need. Meats, eggs, and dairy products are significant sources of protein, but you can also get protein from a variety of grains, legumes, nuts, and seeds.
Proteins tend to be large molecules made up of several building blocks called amino acids. The general structure of any amino acid molecule includes a carboxyl group of atoms, an amine group and a side chain. The carboxyl group contains one carbon, two oxygen, and one hydrogen atom. The amine group contains one nitrogen atom with two hydrogen atoms attached to it.All 20 amino acids have different side chains, which vary in shape including straight chains of atoms, branched chains of atoms and rings of atoms. The side chains may include carbon, hydrogen, sulfur, nitrogen and oxygen atoms. The configuration and molecules found in the side chain is what differentiates one amino acid from another. The branched-chain amino acids are isoleucine, leucine, and valine. These amino acids are necessary for muscle structure. Tyrosine, phenylalanine and tryptophan are called aromatic amino acids. Each one contains a side chain with a ring-shaped formation. These three amino acids are needed for neurotransmitter production.
There are 20 different amino acids. Amino acids are linked together to form peptides, which are small chains of amino acids. The peptides are then

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Retrieved Text: This study was designed to compare and identify the adducts formed between rosmarinic acid and amino acids at two different modification conditions. Covalent interactions between different amino acids, including [L-Lysine (L-Lys) and its derivative,tert-butyloxycarbonyl-L-lysine (N-Boc-Lys) and L- cysteine (L-Cys)] and rosmarinic acid (Ros) were conducted with two different methods; alkaline (pH 9) and enzymatic [in the presence of tyrosinase (polyphenoloxidase , PPO)]. The formed adducts were identified and characterized using flow injection electrospray ionization - quadrupole time of flight (FI- ESI-QTOF) mass spectrometry. Many adducts were identified for the first time. The obtained data exhibited slight differences between the adducts formed after alkaline and enzymatic treatment. In case of the incubation of Ros with both methods without amino acids, numerous adducts, such as Ros quinone, Ros dimer and decarboxylated Ros at [M−H] - with an m/z of 359.08, 719.17 and 313.1 Da, respectively, were identified .Otherwise, in the presence of amino acids, the monomer and dimer of Ros were covalently added to the side chains of selected amino acids. Additionally, the covalent attachment between oxidized Ros and the side chains of two molecules of amino acids was also identified. Finally, L- Cys was the most susceptible amino acid to react with oxidized Ros compared to L- Lys and N-Boc-Lys. It could be concluded that, the results show some similarities between the adducts formed at both modification conditions. Moreover, the covalent interactions between Ros and the side chains of molecules of lysine or cysteine may also be expected to occur in proteins.

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Retrieved Text: Amino acids are simple organic compounds made of carbon, hydrogen, oxygen, nitrogen, and, in a few cases, sulfur. Amino acids bond together to form protein molecules, the basic building blocks of all living things. Amino acids can vary widely. Only about 20 amino acids are common in humans and animals, with 2 additional ones present in a few animal species. There are over 100 lesser known amino acids found in other living organisms, particularly plants.
The first few amino acids were discovered in the early 1800s. Although scientists determined that amino acids were unique compounds, they were unsure of their exact significance. Scientists did not understand their importance in the formation of proteins—chemical compounds responsible for the structure and function of all cells—until the first part of the twentieth century.
An important characteristic of amino acids is their ability to join together in chains. The chains may contain as few as 2 or as many as 3,000 amino acid units. Amino acids become proteins when 50 or more are bonded together in a chain.
All the millions of different proteins in living things are formed by the bonding of only 20 amino acids. Like the 26 letters of the alphabet that join together to form different words, the 20 amino acids join together in different combinations and sequences to form a large variety of proteins. But whereas most words are formed by about 10 or fewer letters, proteins are formed by 50 to more than 3,000 amino acids. Because each amino acid can be used many times along the

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Retrieved Text: tera’s® provides the highest quality, nutrition for your vibrant lifestyle.
A reduced calorie, higher protein diet including whey protein may improve the quality of weight loss by helping you lose more fat and/or maintain more lean muscle.
Calorie for calorie, whey protein can help people feel fuller for much longer than carbohydrates or fats can, keeping you from feeling hungry again.
Consuming whey protein and performing resistance exercise can help build more lean muscle than resistance training alone or combined with carbohydrate consumption.
Consuming whey protein after exercise helps to build and repair muscle. That means you can get back to a workout quicker.
Research shows older Americans can reduce age-related decline of muscle mass with resistance training and more protein.
Every person, at every age, needs to consume adequate protein to replenish their body each day. Everyone can benefit from protein, but for some, including athletes and older adults, the standard requirement isn’t enough. They need to consume additional protein in order to meet their protein needs.
Protein sources are broken down into two categories: complete and incomplete. Complete protein sources provide all of the essential amino acids that your body needs to maintain muscle function and stay healthy. Complete protein sources include animal-based protein sources: meat, fish, eggs and dairy products.
Whey protein comes from milk, and therefore it’s a complete source of protein, providing every essential amino acid that your body needs daily.
In contrast, incomplete protein sources are missing one or more of the essential amino acids. Incomplete protein sources include plant foods: beans, peas, seeds, nuts, vegetables and grain products.

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Retrieved Text: The Branched Chain Amino Acids Leucine, Isoleucine, and Valine are so called because the side chains of these amino acids (the part of the molecule that differentiates the amino acids) are made up of non-linear (branching) carbon chains. BCAAs are essential amino acids, meaning that they must be consumed in the diet (rather than manufactured in the body) and constitute more than one-third of the amino acid composition of skeletal muscle. As a dietary supplement, BCAAs help support increased muscle metabolism and increased energy production, making them an ideal recovery aid following intense exercise.✝ True Nutrition's BCAA Capsules are derived from fermented plant-based ingredients, and are entirely vegan-friendly!
As a dietary supplement, take 1 Serving (4 Capsules) between meals, 30-45 minutes before workouts, and/or immediately after workouts.
By far the Best BCAA supplement I have taken. Easy to consume and it definitely gives me the quality and results Im looking for. However, for 200 capsules which is equivalent to 50 servings I found out i got only 46 out of that and 1 extra capsule. I just hope on my next order the issue will be resolved and hopefully no one else runs across it.

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Retrieved Text: Hemp is a food with a number of nutrients beneficial to the body. One of its best qualities is that it is a good source of protein, especially for individuals looking for alternative healthy ways to meet their protein needs. However, it is important to know whether hemp is a complete protein resource that can help meet daily intake recommendations.
Proteins consist of chains of amino acids. The body can make 10 amino acids itself. However, there are 10 amino acids the body cannot produce, so you must get them through diet. These are called essential amino acids. Hemp contains all of the essential amino acids. According to the University of Arizona Biology Project, an insufficient intake of even one of the essential amino acids can result in the breakdown of muscle.
Proteins can be classified as complete or incomplete. Complete proteins are those that contain all the essential amino acids in sufficient quantities. Meat, eggs, fish, poultry and dairy products are all sources of complete proteins. Incomplete proteins are those that do not have one or more of the essential amino acids. Beans, nuts, peas and grains are examples of incomplete proteins. Hemp, because it has all of the essential amino acids, is classified as a complete protein.
One of the drawbacks to obtaining protein from meat and dairy sources can be the amount of saturated fat in these foods. Hemp is a suitable alternative because it is not only a complete protein but also low in saturated fats. Hemp contains a significant amount of omega-3 fatty acids

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Retrieved Text: A protein molecule comprises a string of linked amino acids, folded into a complex globular shape. Digesting the protein in the foods you eat involves unfolding the protein chain and then unlinking the amino acids it contains. These amino acids, once your body absorbs them, become incorporated into new proteins that your body synthesizes as needed. Digestion of protein occurs in your stomach and small intestine with the help of enzymes secreted by your pancreas.
After you chew and swallow your food, the low pH of your stomach acid begins to denature, or unfold, the proteins you consume. This unfolding is important because it allows digestive enzymes to access the bonds holding the individual amino acids together. The gastric juice in your stomach contains a protease, or protein-degrading enzyme, called pepsin, and pepsin cleaves the large, bulky, unfolded protein molecule into smaller pieces of protein known as peptides. The microorganisms you may inadvertently consume with your food usually die in the presence of your stomach acid, and the proteins they contain join your pool of food proteins in the digestive process.
Although no protein digestion occurs within your pancreas, this organ is essential in the digestion process. Your pancreas secretes a bicarbonate-containing buffer that serves to neutralize your gastric contents as they move out of your stomach and into your small intestine. This matters because, with the exception of pepsin, your digestive proteases and peptidases are not active at the low pH of your stomach acid. The digestive enzymes trypsin, chymotrypsin and carboxypeptidase, secreted by your pancreatic cells,

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Retrieved Text: 2. 2 Biomoléculas e Alimentação  Análise de um filme e realização de um Kahoot (ferramenta TIC de ensino aprendizagem) em inglês, no âmbito do estudo das biomoléculas e alimentação.  Aula desenvolvida cooperativamente pelas docentes de física e química, inglês e biologia e geologia, no âmbito dos projetos: • KA1 - "+ Literacia: da Minha Escola Leio o Mundo"; • CLIL (Content and Language Integrated Learning); • PES (Promoção e Educação para a Saúde).  Material utilizado: • Filme https://www.youtube.com/watch?v=YO244P1e9QM • Kahoot construído com as questões e opções de resposta contidas nas páginas seguintes.
12. Carbohydrates 12 Among the most common polysaccharides there is to consider ...  Glycogen and cellulose, as constituents of cell walls, respectively, of fungi and plants.  Starch and glycogen, with energy reserve functions, cellulose and chitin, with structural functions.  Chitin and starch, with energy reserve function, respectively in animals and plants.  Starch and sucrose with energy reserve functions in plants.
16. 16 Proteins Proteins ...  are polymers of amino acids, formed only by a polypeptide chain.  differ from one another in the type, number, and order of the amino acids that constitute them.  have an ill-defined three-dimensional conformation.  are polymers of fatty acids, formed by one or more polypeptide chains.
19. 19 Chemical bonds The glycosidic, ester and peptidic bonds are established, respectively, between ...  Amino acids, fats and monosaccharides.  Amino acids, fatty acid and glycerol and monosaccharides.  Monosaccharides, fatty acids and amino acids.  Monosaccharides, constituents of lipids and amino acids.
21. 21

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Input Text: Answer the following question given this paragraph: 

Outcomes of Glycolysis Glycolysis starts with glucose and ends with two pyruvate molecules, a total of four ATP molecules and two molecules of NADH. Two ATP molecules were used in the first half of the pathway to prepare the six-carbon ring for cleavage, so the cell has a net gain of two ATP molecules and 2 NADH molecules for its use. If the cell cannot catabolize the pyruvate molecules further, it will harvest only two ATP molecules from one molecule of glucose. Mature mammalian red blood cells are not capable of aerobic respiration—the process in which organisms convert energy in the presence of oxygen—and glycolysis is their sole source of ATP. If glycolysis is interrupted, these cells lose their ability to maintain their sodium-potassium pumps, and eventually, they die. The last step in glycolysis will not occur if pyruvate kinase, the enzyme that catalyzes the formation of pyruvate, is not available in sufficient quantities. In this situation, the entire glycolysis pathway will proceed, but only two ATP molecules will be made in the second half. Thus, pyruvate kinase is a rate-limiting enzyme for glycolysis.


Q: What process starts with glucose and ends with two pyruvate molecules, a total of four atp molecules and two molecules of nadh?

 Choices:

- glycolysis

- secretion

- absorption

- photosynthesis

A:

Target Text: glycolysis

#### Retrieved Documents ####

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Retrieved Text: What Molecules Enter the Krebs Cycle & What Molecules Leave the Krebs Cycle?
What Happens When There Is No Oxygen Available at the End of Slow Glycolysis?
What Follows Glycolysis if Oxygen Is Present?
What Is Produced As a Result of Photosynthesis?
Living things, all of which consist of one or more individual cells, can be divided into prokaryotes and eukaryotes. Virtually all cells rely on glucose for their metabolic needs, and the first step in the breakdown of this molecule is the series of reactions called glycolysis (literally, "glucose splitting"). In glycolysis, a single glucose molecule undergoes a series of reactions to yield a pair of pyruvate molecules and a modest amount of energy in the form of adenosine triphosphate (ATP).
The ultimate handling of these products, however, varies from cell type to cell type. Prokaryotic organisms do not participate in aerobic respiration. This means that prokaryotes cannot make use of molecular oxygen (O2). Instead, the pyruvate undergoes fermentation (anaerobic respiration).
Some sources include glycolysis in the process of "cellular respiration" in eukaryotes, because it directly precedes aerobic respiration (i.e., the Krebs cycle and oxidative phosphorylation in the electron transport chain). More strictly, glycolysis itself is not an aerobic process simply because it does not rely on oxygen and occurs whether or not O2 is present. However, since glycolysis is a prerequisite of aerobic respiration in that it supplies pyruvate for the reactions thereof, it is natural to learn about both concepts at once.
Glucose is a six-carbon sugar that serves as the most important single carbohydrate in human biochemistry. Carbohydrates contain

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Retrieved Text: 138 UNIT 1 Th e Cell 8.2 Outside the Mitochondria: Glycolysis Learning Outcomes Upon completion of this section, you should be able to 1. Describe the location where glycolysis occurs in the cell. 2. Compare the amount of carbon between input and output of glycolysis. 3. Explain how energy-investment and energy-harvesting steps of glycolysis result in 2 net ATP. Glycolysis, which takes place within the cytoplasm outside the mitochondria, is the breakdown of C 6 (6-carbon) glucose to two C 3 (3-carbon) pyruvate molecules. Since glycolysis occurs universally in organisms, it most likely evolved before the citric acid cycle and the electron transport chain. This may be why glycolysis occurs in the cytoplasm and does not require oxygen. There was no free oxygen in the early atmosphere of the Earth. Glycolysis is series of ten reactions, and just as you would expect for a metabolic pathway, each step has its own enzyme. The pathway can be conveniently divided into the energyinvestment step and the energy-harvesting steps. During the energy-investment step, ATP is used to “jump-start” glycolysis. During the energy-harvesting steps, four total ATP are made, producing 2 net ATP overall. Energy-Investment Step As glycolysis begins, two ATP are used to activate glucose by adding phosphate. Glucose eventually splits into two C 3 molecules known as G3P, the same molecule produced during photosynthesis. Each G3P has a phosphate group, each of which is acquired from an ATP molecule. From this point on, each C 3 molecule undergoes the same series of reactions. Energy-Harvesting Step Oxidation of G3P

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Retrieved Text: Aerobic respiration uses oxygen to break down glucose, amino acids and fatty acids and is the main way the body generates adenosine triphosphate (ATP), which supplies energy to the muscles. After glycolysis (the anaerobic breakdown of glucose into pyruvate – see our separate article for more detail), pyruvate is converted to acetyl CoA in the matrix of the energy-transferring mitochondria, via the link reaction. Next is the Krebs cycle, which occurs twice per glucose molecule, producing – among other chemicals that feed into the aerobic part of the process – more ATP.
A diagram showing the stages of the link reaction and Krebs cycle, taken from our cellular respiration poster.
The aerobic part of the process depends on a series of protein complexes that are organised along the folds of the inner membrane (cristae) of the mitochondria. These are arranged so that electrons pass from one reacting molecule to the next, in a series of steps known as the electron transport chain. This process ends with ATP synthase, an enzyme that produces ATP from adenosine diphosphate (ADP) and inorganic phosphate (up to around 30 molecules of ATP per molecule of glucose, according to current thinking), capturing the final portion of the energy released by the whole process in a form that the rest of the cell can use.
Below, we look a little closer at the specific reactions that take place during the steps of aerobic respiration.
The link reaction occurs in the mitochondrial matrix, and converts pyruvate into the two-carbon molecule acetyl CoA by removing carbon dioxide and hydrogen,

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Retrieved Text: Where does the energy come from that power the recharging of the ATP molecule?
Cellular Respiration is a chemical process that occurs in all living cells, when trapped energy in the bonds of food molecules are converted to the stored energy in ATP molecules.
Cellular Respiration is a series of chemical reactions that frees the energy in food molecules, making it available to cells.
The chemical process of Cellular Respiration starts when a food molecule (i.e. glucose) enters the cell and is acted upon by the enzymes in the cytoplasm of the cell.
The steps of Cellular Respiration are controlled by ENZYMES.
This process takes place in the MITOCHONDRIA, in the presence of oxygen and is called AEROBIC RESPIRATION (oxygen requiring).
Respiration is generally defined as OXYGEN-REQUIRING; but respiration can also occur WITHOUT OXYGEN (ANAEROBIC RESPIRATION).
– Glycolysis is the 1st series of chemical reactions in cellular respiration, in which glucose is converted to pyruvic acid.
– The entire process can take place whether or not oxygen is present. So Glycolysis is sometimes referred to as ANAEROBIC RESPIRATION.
– It is a series of reactions that take place in the CYTOPLASM of the cell.
– Each chemical reaction is catalyzed (to cause an action to begin) by an enzyme.
– The chemical reactions of glycolysis are anaerobic, because they occur without oxygen.
– All organisms can carry on glycolysis.
– Once GLUCOSE is present in the cell, its chemical bonds are broken down by glycolysis, with the help of enzymes, releasing free energy to make ATP.
– Glucose is not the only cellular fuel. ALL SIMPLE SUGARS in the diet

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Retrieved Text: The equation of cellular respiration provides information about the products and reactants of this most important biochemical process. Read to know how this process, the most crucial chemical reaction of life, works in every cell of the body.
Every organism on Earth needs energy for survival. Its life is sustained through the process of respiration at the cellular level, which provides the requisite energy. This process makes every cell an independent unit that creates its own energy. This process of deriving energy is quite complex but it can be adequately summed up with the help of the chemical equation presented further.
Respiration, at the cellular level, is a set of connected metabolic processes that are directed towards converting stored biochemical energy in food, into ATP (Adenosine Triphosphate) molecules, which are the body's energy currency. Through subtle manipulation, with the help of enzymes, energy in the form of ATP molecules is derived from glucose. The production of glucose in turn, is done by plants, through the process of photosynthesis. Glucose and complex carbohydrates, created by plants, are consumed by other animals and processed to derive energy.
Food in the form of carbohydrates and fats is first broken down to simpler form of glucose molecules, which are then processed inside the cell to create ATP molecules.
Every action in the human body is made possible through use of the ATP molecules. That is why, they are called the energy currency of the body. Energy is derived through the conversion of ATP into ADP (Adenosine Diphosphate).
Every metabolic process, including cellular respiration, is complex

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Retrieved Text: Find Anaerobic Glycolysis. Examine Now.
After glycolysis, the two pyruvates produced from one molecule of glucose are converted into acetyl CoA. This process occurs in the mitochondrion of the cell.
Start studying Biology Chapter 9 Quiz. Learn vocabulary, terms, and more with flashcards, games, and other study tools. ... If oxygen is NOT present after glycolysis, what occurs next? Fermentation. If oxygen is present after glycolysis what process occurs next. Krebs Cycle. Process that doesn't require oxygen? Anaerobic.
Glycolysis converts a molecule of sugar into two molecules of pyruvate, also producing two molecules each of adenosine triphosphate (ATP) and nicotinamide adenine dinucleotide (NADH). When oxygen is absent, a cell can metabolize the pyruvates through the process of fermentation.
Glycolysis can occur with or without oxygen. In the presence of oxygen, glycolysis is the first stage of cellular respiration. In the absence of oxygen, glycolysis allows cells to make small amounts of ATP through the process of fermentation. Glycolysis takes place in the cytosol of the cell's cytoplasm.
How Does Glycolysis Work? Glycolysis generally occurs in the cytosol of a cell, and occurs both aerobically (with the presence of oxygen) and anaerobically (without the presence of oxygen). The availability of oxygen determines the type of process that will occur after glycolysis, as will be discussed later in this article.
Glycolysis (from glycose, an older term for glucose + -lysis degradation) is the metabolic pathway that converts glucose C 6 H 12 O 6, into pyruvate, CH 3 COCOO − + H +.The free energy released in this process is used to form the

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Retrieved Text: 2. The Basics of Cellular Respiration Cellular respiration releases energy by breaking down glucose and other food molecules in the presence of oxygen. 6 O2 + C6H12O6 6 CO2 + 6 H2O + Energy Cellular respiration takes place in small steps to minimize the loss of energy in the form of heat or light. Processes that require oxygen to take place are called aerobic. Processes that do not require oxygen to take place are anaerobic.
ATP molecules can be produced in two ways: Substrate level phosphorylation -- when enzymes directly transfer phosphate to ADP during chemical reactions. Oxidative phosphorylation When ATP synthesis is fueled by creating a concentration difference of H ions between two sides of the cell membrane.
III. Fermentation (an alternative if oxygen is not present) After glycolysis fermentation will take place if oxygen is not present in the organism. Fermentation will recycle the used NADH into NAD +. Fermentation forms a total of 2 ATP molecules from one glucose.
Products: 6 NADH, 2 FADH 2, 4 CO 2, 2 ATP from each glucose molecule. The first step of this process is to break down pyruvic acid into an acetyl group that binds with a Coenzyme-A the complex that is formed is called Acetyl-CoA. This is called the intermediate step. Acetyl-CoA starts the Krebs cycle that will extract energy and electrons from organic molecules.
VI. Comparing Aerobic Respiration and Fermentation While fermentation can take place without oxygen and is a simpler process, it produces only 2 ATP molecules from glucose. It also produces some harmful chemicals (ethanol or

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Retrieved Text: All parts of the body (muscles, brain, heart, and liver) need energy to work. This energy comes from the food we eat. It happens due to some sequential biochemical phenomenon known as metabolism.
The endocrine system stimulates reactions of metabolism by releasing hormones like cortisol, glucagon and adrenaline; digestive system provides nutrients; nutrients through blood; respiratory system provides oxygen and excretory system eliminates waste. So metabolism which is the most important function in maintaining life can happen only with perfect coordination of all other systems in the body.
Metabolism refers to all chemical reactions occurring in living organisms, including digestion and the transport of substances into and between different cells to sustain life. These processes allow the living organisms to grow and reproduce, maintain their structures, and respond to their environments.
Metabolism is the set of chemical reactions that happen in the cells of living organisms to sustain life. These processes allow organisms to grow and reproduce, maintain their structures, and respond to their environments. The word metabolism can also refer to all chemical reactions that occur in living organisms, including digestion and the transport of substances into and between different cells.
Metabolism is usually divided into two categories - catabolism and anabolism. Catabolism breaks down organic matter, for example to harvest energy in cellular respiration. Anabolism uses energy to construct components of cells such as proteins and nucleic acids. The chemical reactions of metabolism are organized into metabolic pathways, in which one chemical is transformed through a series of steps into another chemical, by a sequence of enzymes. Enzymes

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Retrieved Text: In eukaryotic cells, the pyruvate molecules produced at the end of glycolysis are transported into mitochondria. Mitochondria are sites of cellular respiration; In the presence of oxygen, aerobic respiration will proceed. In mitochondria, pyruvate will be transformed into a two-carbon acetyl group by removing a molecule of carbon dioxide. This acetyl group is picked up by a carrier compound called coenzyme A (CoA), which is made from vitamin B5. The resulting compound is called acetyl CoA. (Figure 3). Acetyl CoA can be used in a variety of ways by the cell, but its major function is to deliver the acetyl group derived from pyruvate to the next pathway in glucose catabolism.
Figure 3 Pyruvate is converted into acetyl-CoA before entering the citric acid cycle.
3 NADH and 2 FADH2, which carry energy to the last part of the aerobic respiration pathway.
Part of this is considered an aerobic pathway (oxygen-requiring) because the NADH and FADH2 produced must transfer their electrons to the next pathway in the system, which will use oxygen. If oxygen is not present, this transfer does not occur. The citric acid cycle does NOT occur in anaerobic respiration.
Two carbon atoms come into the citric acid cycle from each acetyl group. Two carbon dioxide molecules are released on each turn of the cycle; however, these do not contain the same carbon atoms contributed by the acetyl group on that turn of the pathway. The two acetyl-carbon atoms will eventually be released on later turns of the cycle; in this way, all six carbon atoms from the original

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Retrieved Text: Current time: And so, of course, maybe the question we should really be asking is how many protons does it take, or how many protons need to flow through this ATP synthase to phosphorylate one molecule of ADP into ATP, and so, I'm actually gonna go ahead back to our ratios up here and write up here that if we knew how many protons were necessary to produce one molecule of ATP, we would be able to calculate essentially the ratio of ATP to NADH or FADH two.
So, of course, to get back to this kind of elusive calculation of ATP, researchers have done controlled studies in which they basically take a known amount of NADH or FADH two and they have mitochondria available in the lab, and they basically allow the mitochondria to oxidatively phosphorylate these molecules and essentially measure how much ATP is produced, but kind of to their surprise at first, they found that for NADH, for one molecule of NADH, they calculated, there was not a whole number of ATP produced, in fact, they found that there was somewhere between two to three ATP molecules produced for every one NADH molecule.
And this oxidative refers to the fact that this process requires oxygen and in fact, the importance of oxygen here is that this oxygen is reduced by electron carrier molecules and something called the electron transport chain so, remember that we have a electron carrier molecules called NADH and FADH two that are produced at various stages of cellular respiration, glycolysis, the

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Retrieved Text: Photosynthesis and aerobic respiration are both part of a cyclic process of biochemical reactions. Photosynthesis requires the products of aerobic respiration (carbon dioxide and water), while aerobic respiration requires the products of photosynthesis (glucose and oxygen). Together, these reactions are involved in how cells make and store energy. The energy transfers in both processes and in how the gas exchange between oxygen and carbon dioxide occurs and the end products that result from each process are somewhat opposite processes, thus aerobic respiration and photosynthesis are in some ways complete opposites of each other. Photosynthetic organisms such as plants use solar energy to reduce carbon dioxide into carbohydrates. During respiration glucose is oxidised back to carbon dioxide, in the process, releasing energy that is captured in the bonds of ATP. Although these two energy producing processes differ in their uses and also their goals, they do have several similarities.
Photosynthesis is a chemical process that takes place in the presence of sunlight, wherein plants manufacture their food and build stores of energy. This phenomenon occurs in chlorophyll containing plant cells. Chlorophyll is a pigment found in plant leaves that gives the plant its green colour. Chlorophyll absorbs the light energy and utilises it to produce carbohydrates from carbon dioxide and water. These carbohydrates produced are used by the plants as a source of immediate energy for growth, reproduction, and absorption of nutrients. The chemical reaction produces oxygen which is released into the atmosphere.
Occurring in the chloroplast light reaction converts solar energy to chemical energy of ATP and NADPH.The

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Retrieved Text: Glycolysis is the metabolic process that serves as the foundation for both aerobic and anaerobic cellular respiration. In glycolysis, glucose is converted into pyruvate. Glucose is a six- memebered ring molecule found in the blood and is usually a result of the breakdown of carbohydrates into sugars. It enters cells through specific transporter proteins that move it from outside the cell into the cell’s cytosol. All of the glycolytic enzymes are found in the cytosol.
Here, the glucose ring is phosphorylated. Phosphorylation is the process of adding a phosphate group to a molecule derived from ATP. As a result, at this point in glycolysis, 1 molecule of ATP has been consumed.
The reaction occurs with the help of the enzyme hexokinase, an enzyme that catalyzes the phosphorylation of many six-membered glucose-like ring structures. Atomic magnesium (Mg) is also involved to help shield the negative charges from the phosphate groups on the ATP molecule. The result of this phosphorylation is a molecule called glucose-6-phosphate (G6P), thusly called because the 6′ carbon of the glucose acquires the phosphate group.
The second step of glycolysis involves the conversion of glucose-6-phosphate to fructose-6-phosphate (F6P). This reaction occurs with the help of the enzyme phosphoglucose isomerase (PI). As the name of the enzyme suggests, this reaction involves an isomerization reaction.
The reaction involves the rearrangement of the carbon-oxygen bond to transform the six-membered ring into a five-membered ring. To rearrangement takes place when the six-membered ring opens and then closes in such a way that the first carbon becomes now external to the ring.
In the

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Retrieved Text: Aerobic cellular respiration is a part of cellular respiration, and it plays an important role in producing the energy that is required for various functions of a cell.
All organisms are made up of tiny cells which carry out various functions. Energy is required for processing these functions. This energy is provided by the cells, and is produced when the cells break down the chemical composition of food molecules and convert them into energy, i.e. convert glucose to energy. This is made possible with the process called cellular respiration, which takes place in the mitochondrion - the power house of a cell. During this process, cells break down glucose molecules and release energy. This energy that is released from the glucose is used to produce ATP. Therefore, cellular respiration is the process by which energy from glucose is transferred to ATP. It is a part of metabolism and all organisms go through cellular respiration.
Cellular respiration is of two types - anaerobic respiration and aerobic respiration. Here, we shall discuss aerobic respiration.
Cellular respiration is vital for the survival of all organisms, as energy from food (glucose) cannot be used by a cell until it is converted to ATP. Hence, it is a continuous cycle that takes place in all organisms. Aerobic respiration plays a crucial role in the production of ATP, where glucose and oxygen are vital elements. This process takes place only if oxygen is available. Take a look at the chemical formula given here.
Aerobic respiration takes place in three phases - Glycolysis, Krebs Cycle, and Oxidative

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Retrieved Text: Is water polar or non polar?
Chemical energy is what type of energy and where is it stored?
What type of bonds are in water? Why is it like this?
Which types of molecules are hydrophilic?
Which types of molecules are hydrophobic?
Why can water absorb such a large capacity of heat?
What is the basis of the pH scale and what does the scale express?
When does chemical equilibrium occur?
In cells most proteins are ___ that function as _____.
What makes amino acids are reactive and stable in water?
What side chains make an amino acid more chemically reactive?
Does polymerization require energy? Is it spontaneous?
What type of reaction of monomers polymerize through?
Amino acids are connected by ___ which form in ____ reactions.
What forms a proteins secondary structure?
In nucleic acid polymerization, how many phosphates are transferred and what does the process create?
What raises potential energy in molecules?
Which base pairs have 2 hydrogen bonds and which have 3?
Why does DNA make a poor catalyst?
Why is RNA more reactive?
In a monosaccharide, what is the difference between aldose and ketose?
Plants store sugar as ___ and animals store it as ____.
How do carbohydrates provide structure?
Why do biologists not thing that polysaccharides played no part in the origin of life?
Why do carbohydrates have more free energy than CO2?
What enzyme do most animal cells contain so that they are able to readily break down glycogen to provide glucose?
What are plasma membranes made up of?
What kind of permeability do phospholipid bilayers have?
What kind of molecules can pass through a phospholipid bilayer?
Factors that influence the behavior of the membrane?
Difference between unsaturated and saturated

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Retrieved Text: This is to be transported into mitochondria by a Pyruvate transporter. It is a simport, where the hydrogen ion is a transporter. Here two different enzymes are involved based on the condition. They are Pyruvate dehydrogenase and Lactate dehydrogenase enzymes. There are 2 different conditions are monitored by the Pyruvate fate.
Glycolysis occurs in both aerobic respiration and anaerobic respiration. During this stage, each glucose molecule splits in half, forming two molecules of pyruvate. If oxygen is present, the pyruvate breaks down further into carbon dioxide, hydrogen ions and an electron transport molecule called NADH (the reduced form of nicotinamide-adenine dinucleotide).
the fate of pyruvate after glycolysis depends on if you have ____ or not. oxygen. in order for pyruvate to go into the krebs cycle it must have ____ hub. ... which krebs cycle intermediate helps to regulate the overall rate of glycolysis by direct influence on the activity of phospfructokinase.
The Fate of Pyruvate (30 pts): During anaerobic exercise or fermentation, the pyruvate produced by glycolysis is further processed to give lactate (in muscle) or ethanol and carbon dioxide (in yeast), as shown below. When we ingest ethanol, it is metabolized by liver alcohol dehydrogenase. Pyruvate is given at the right.
Although glycolysis doesn’t require oxygen, the fate of the pyruvate molecules depends on whether oxygen is present. If oxygen isn’t available, the pyruvate is converted to lactate, and no additional ATP is produced from this conversion. If oxygen is present, the pyruvates are transported into the mitochondrial matrix.
After glycolysis and citric acid cycle, what is the fate

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Retrieved Text: first law of thermodynamics Energy cannot be created or destroyed.
second law of thermodynamics Energy tends to disperse spontaneously.
potential energy Energy stored in the position or arrangement of a system’s components.
reactants Molecule that enters a reaction and is changed by participating in it.
endergonic Describes a reaction that requires a net input of free energy.
exergonic Describes a reaction that ends with a net release of free energy.
Activation energy Minimum amount of energy required to start a reaction.
catalysis The acceleration of a reaction rate by a molecule that is unchanged by participating in the reaction.
substrates Molecule that an enzyme acts upon and converts to a product; reactant in an enzyme-catalyzed reaction.
induced-fit model Of enzyme activity, interacting with a substrate causes the active site to change shape so that the fit between them improves and catalysis occurs.
metabolic pathway Series of enzyme-mediated reactions by which cells build, remodel, or break down an organic molecule.
allosteric regulation Control of an enzyme’s activity by a regulatory molecule that binds outside the active site.
feedback inhibition Regulatory mechanism in which a change that results from some activity decreases or stops the activity.
electron transfer chain In a cell membrane, series of enzymes and other molecules that accept and give up electrons, thus releasing the energy of the electrons in small, usable steps.
cofactors A coenzyme or metal ion that associates with an enzyme and is necessary for its function.
antioxidants substance that interferes with the oxidation of other molecules.
phosphorylation Reaction in which a phosphate group is added to a molecule.
ATP/ADP cycle Process by which cells regenerate ATP. ADP forms

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Retrieved Text: B.D.S from Govt dental college, ahmedabad. Cleared Aipmt-06 renowned faculty of Biology since 2011.
All the energy required for ‘life’ processes is obtained by oxidation of some macromolecules that we call ‘food’.
Only green plants and cyanobacteria can prepare their own food; by the process of photosynthesis they trap light energy and convert it into chemical energy that is stored in the bonds of carbohydrates like glucose, sucrose and starch.
In green plants too, not all cells, tissues and organs photosynthesise; only cells containing chloroplasts, that are most often located in the superficial layers, carry out photosynthesis.
Hence, even in green plants all other organs, tissues and cells that are non-green, need food for oxidation. Hence, food has to be translocated to all non- green parts.
Animals are heterotrophic, i.e., they obtain food from plants directly (herbivores) or indirectly (carnivores). Saprophytes like fungi are dependent on dead and decaying matter.
Ultimately all the food that is respired for life processes comes from photosynthesis.
Photosynthesis, of course, takes place within the chloroplasts (in the eukaryotes), whereas the breakdown of complex molecules to yield energy takes place in the cytoplasm and in the mitochondria (also only in eukaryotes).
The compounds that are oxidised during this process are known as respiratory substrates. Usually carbohydrates are oxidised to release energy, but proteins, fats and even organic acids can be used as respiratory substances in some plants, under certain conditions.
The energy released by oxidation in respiration is not used directly but is used to synthesise ATP, which is broken down whenever and wherever energy needs to be utilised. Hence,

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Retrieved Text: During rapid, high-intensity exercise, your muscles use large amounts of energy in the form of a compound called adenosine triphosphate, or ATP. To allow you to keep working out, ATP stores must be replenished quickly. Muscles utilize both anaerobic and aerobic metabolism to produce ATP, but during fast-paced, strenuous exercise, anaerobic metabolism predominates.
Your cells store energy in the form of ATP. When muscles contract, they break down ATP in a reaction that provides energy. However, muscle cells only store enough ATP to fuel a few seconds of maximal contraction. To keep working, they must replenish their ATP supply. They can do this for a short period of time by breaking down another high-energy compound called creatine phosphate. Because stores of creatine phosphate are also limited, this energy system, called the phosphagen system, can only sustain maximal muscle output for about 10 seconds. The phosphagen system is the primary energy source during very short, rapid bursts of activity, such as a sprint.
To sustain exercise for more than 10 seconds, muscles must break down fuel sources such as carbohydrates and fats to provide the energy to re-synthesize ATP. Carbohydrate metabolism is faster than fat metabolism, so carbs provide a high percentage of the energy used during very high-intensity workouts. Because carbs can be metabolized anaerobically, without oxygen, they become a vital energy source when oxygen supply to your muscles can't keep up with demand.
The breakdown of carbs to provide energy without oxygen is called anaerobic glycolysis. This process releases energy very rapidly. Glucose, or blood sugar, and stored

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Retrieved Text: We usually talk of energy in general terms, as in “I don’t have a lot of energy today” or “You can feel the energy in the room.” But what really is energy? Where do we get the energy to move? How do we use it? How do we get more of it? Ultimately, what controls our movements? The three metabolic energy pathways are the phosphagen system, glycolysis and the aerobic system. How do they work, and what is their effect?
Albert Einstein, in his infinite wisdom, discovered that the total energy of an object is equal to the mass of the object multiplied by the square of the speed of light. His formula for atomic energy, E = mc2, has become the most recognized mathematical formula in the world. According to his equation, any change in the energy of an object causes a change in the mass of that object. The change in energy can come in many forms, including mechanical, thermal, electromagnetic, chemical, electrical or nuclear. Energy is all around us. The lights in your home, a microwave, a telephone, the sun; all transmit energy. Even though the solar energy that heats the earth is quite different from the energy used to run up a hill, energy, as the first law of thermodynamics tells us, can be neither created nor destroyed. It is simply changed from one form to another.
The energy for all physical activity comes from the conversion of high-energy phosphates (adenosine triphosphate—ATP) to lower-energy phosphates (adenosine diphosphate—ADP; adenosine monophosphate—AMP; and inorganic phosphate, Pi). During

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Retrieved Text: Let’s say you run as fast as you can for a minute. The first 10 seconds or so are pretty easy, but then you can’t run as fast anymore. With each passing moment your muscles burn a little more, and your speed slows. What’s happening?
We’ll start with those first 10 seconds that were relatively easy, when your speed was fastest. The first one or two seconds were fueled by the ATP stored within your muscles. Then the next five seconds were primarily fueled by your phosphagen system, which is stored phosphocreatine (PC) within your muscles. So those first seven seconds came from a combination of ATP and PC, and that’s why it’s sometimes called the ATP-PC system, instead of the phosphagen system. Different name, same thing.
Before we move on, it’s worth noting here that even though the phosphagen system is typically described as lasting 10 seconds, in reality it can last up to 30 seconds, depending on the athlete and his/her previous training.
You know that you can’t run at your top speed, or perform a maximum isometric hold, for more than 10 seconds before things start heading south. That’s because your body’s quickest, “cleanest” energy source, the phosphagen system, has been taken over by your next quickest source for energy: glucose.
How does the body get energy from glucose? Let’s briefly cover a little biochemistry.
The foundation of the glucose molecule is a six-carbon structure. Those six carbons are split into two, three-carbon molecules, which are pyruvate. So anaerobic glycolysis consists of splitting one glucose molecule into two

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Retrieved Text: *At this point in the cycle, the hydrogen carrier is FAD (flavine adenine dinucleotide).
Chemical reactions of the citric acid cycle. NADH molecules carrying hydrogens are highlighted.
Figure 4.12, shows that NADH can release the electrons and hydrogen nucleus. Since this reaction removes electrons, the resulting NAD+ is said to be oxidized. Oxidation results from the removal of electrons, often as part of hydrogen atoms; it is the opposite of reduction. The two electrons this reaction releases pass to a series of electron carriers. The regenerated NAD+ can once again accept electrons, and is recycled.
Chapter 4 (pp. 118—119). As electrons are passed from one carrier to another, the carriers are alternately reduced and oxidized as they accept or release electrons. The transported electrons gradually lose energy as they proceed down the chain.
Physiology, Ninth Edition Respiration/Nucleic Acids on which the energy reactions take place. In a muscle cell, the inner mitochondrial membrane, if stretched out, may be as much as forty-five times as long as the cell membrane!
Thus, oxygen is the final electron acceptor. In the absence of oxygen, electrons cannot pass through the electron transport chain, NAD+ cannot be regenerated, and aerobic respiration halts.
Note in figure 4.12 that as electrons pass through the electron transport chain, energy is released. Some of this energy is used by a mechanism involving the enzyme complex ATP synthase to combine phosphate and ADP by a high-energy bond (phosphorylation), forming ATP. Also note in fig ures D.1 and D.2 that twelve pairs of hydrogen atoms are released during the complete breakdown of one

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Retrieved Text: How can Vinpocetine help Us?
The brain is the control center of all physical and intellectual activity in the body. Ten billion different cells, with millions upon millions of neurons, forming connections several hundred times more numerous than the world's population. At the age of thirty cell units die and are never replaced again, thus beginning an inexorable process that becomes more and more acute in the elderly.
The brain normally receives 15-20% of the body's total blood supply and uses 15-20% of the body's totaled inhaled oxygen. The brain must use this oxygen, along with glucose to produce and use 15-20% of the body's total ATP energy. Unlike most other cells, which can burn fat or sugar (glucose) for their energy needs, neurons can only burn glucose under normal conditions, they typically consume 50% of the total blood glucose. Unlike liver and muscle cells, which can store large amounts of sugar as glycogen, neurons can only store at most a minute or two worth of glucose, and so are dependent upon a continuous and uninterrupted blood supply to maintain normal energy metabolism and avoid injury or death.
Most other cells (except heart and skeletal muscle cells) reproduce continually throughout a lifetime yet after the brain reaches a full complement of neurons (birth to 2 years of age), neurons never reproduce, they are an irreplaceable essential of life.
Under normal conditions of adequate oxygen supply, neurons convert glucose into energy (ATP) through a 3-phase process.
The first phase occurs in the cytoplasm of the cell (the gel-like stuff between the nucleus

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Retrieved Text: The Hallmarks of Cancer are ten underlying principles shared by all cancers. The ninth Hallmark of Cancer is defined as “Reprogramming Energy Metabolism”.
Uncontrolled growth defines cancer. Growth requires a cancer’s cells to replicate all of their cellular components; their DNA, RNA, proteins and lipids must all be doubled in order to divide into daughter cells. Of course, this process requires energy. Cancer cells must adjust their metabolism accordingly, to enable this frenzied growth.
Cells require energy to absorb nutrients, to react to changes in their surroundings, to maintain their internal environment, grow, and replicate. Energy is obtained from breaking down nutrients through a process of metabolic reactions known as respiration. This energy is stored in small molecules known as adenosine triphosphate, or ATP. When cells need energy, they use respiration to construct molecules of ATP; they then break down the ATP to fuel their metabolic reactions. Respiration comes in two forms. Normal cells, under normal conditions, undergo aerobic respiration, which is a metabolic pathway that requires oxygen. Here cells break down glucose into pyruvate, to eventually form ATP, while releasing carbon dioxide as a waste product. The oxygen needed is obtained from the air we breathe, diffuses into our blood and is then transported across all our tissues and organs. When there isn’t enough oxygen, cells switch to a different type of respiration: anaerobic respiration. During anaerobic respiration, cells break down glucose into pyruvate and construct ATP, but produce lactic acid instead of carbon dioxide. Aerobic respiration produces far more ATP than anaerobic respiration does; 32 molecules

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Retrieved Text: Outline that cell respiration involves the oxidation and reduction of electron carriers.
State that phosphorylation of molecules makes them less stable.
Outline that in glycolysis, glucose is converted to pyruvate in the cytoplasm.
Explain how glycolysis gives a small net gain of ATP without the use of oxygen.
Explain how, in aerobic cell respiration, pyruvate is decarboxylated and oxidised to form acetyl coenzyme A in the link reaction.
Analyse diagrams of the pathways of aerobic respiration to deduce where decarboxylation and oxidation reactions occur.
Explain how, in the Krebs cycle, the oxidation of acetyl groups is coupled to the reduction of hydrogen carriers, liberating carbon dioxide.
State that energy released by oxidation reactions is carried to the cristae of the mitochondria by reduced NAD and FAD.
Explain how the transfer of electrons between carriers in the electron transport chain in the membrane of the cristae is coupled to proton pumping.
Explain how, in chemiosmosis, protons diffuse through ATP synthase to generate ATP.
Outline that oxygen is needed to bind with free protons to form water to maintain the hydrogen gradient.
Explain how the structure of the mitochondrion is adapted to the function it performs.
Outline that electron tomography can be used to produce images of active mitochondria.
Annotate a diagram of a mitochondrion to indicate the adaptations to its function.
Objectives: Three introductory ideas for respiration. The steps of respiration (what you need to understand). Adaptations of mitochondria.
FAD (Flavine adenine dinucleotide): an electron carrier too, becomes FADH2.
NAD and FAD are similar, but you only find FAD in the krebs cycle while NAD is found in many stages.
Electron transport chain and

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Retrieved Text: As humans, we take the ability to transform food into energy for granted. Eating a chocolate bar while hiking to keep up stamina is seemingly a straightforward and mindless process. However, it relies on a series of very complex biochemical reactions, all interlocking into each other as gears churning away in an engine blowing at full speed.
Most cells in the body can start from common sugar – glucose -and turn it into pyruvate, a small molecule that functions as an intermediary in the cell. The reaction that transforms glucose into pyruvate is known as glycolysis and constitutes one of the most essential building blocks of cellular biochemistry. Once pyruvate is synthesized, it enters a strict series of reactions known as the Citric Acid Cycle (also known as the Krebs Cycle), which uses up pyruvate and oxygen to make carbon dioxide (CO2) and chemical energy (which is released in the form of the small molecule ATP). The Krebs Cycle is the reason why we breathe in oxygen and breathe out carbon dioxide and it takes place within a special compartment in the cell known as a mitochondrion. Mitochondria are often known as the “power plant of the cell” due to their role as hosts of the Krebs Cycle and producers of all chemical energy in the cell. This whole process is known as respiration and is essentially the biochemical groundwork for the mundane business of breathing.
When oxygen is not available, for example in the muscle tissue of an athlete that is straining themselves to the limit, normal

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Retrieved Text: 1.1. Which of the following elements is not normally found in cells?
able to form hydrogen bonds with itself but not with water.
able to form hydrogen bonds with water.
hard to dissolve in a solvent.
incapable of interacting favorably with water.
1.3. For each of the following pairs, indicate whether they interact via hydrogen bonds (H) or ionic bonds (I), or do not favorably interact (N). Your answer would be a four-letter string composed of letters H, I, and N only, e.g. HNNI.
1.4. Which of the following chemicals do you NOT expect to be readily dissolved in water?
1.5. Weak noncovalent attractions in the cell can be very strong in a nonaqueous environment. Some of these attractions are as strong as covalent interactions in a vacuum (their bond energy is approximately 340 kJ/mole), but become more than twenty-five times weaker (their bond energy becomes approximately 13 kJ/mole) in water. What type of attraction shows this phenomenon?
1.6. The bond energies associated with noncovalent attractions in the cell are too weak to resist disruption by thermal motion. However, cellular macromolecules can interact specifically AND strongly with each other (or fold by themselves) merely via such interactions. How is this possible?
The bond energies increase radically when two interacting molecules approach each other.
The interacting molecules also fortify their binding via covalent bonds to keep them from dissociation.
Many weak bonds together in a complementary geometry can afford a strong binding.
The cell lowers its internal temperature to reduce thermal motion of molecules and enhance the weak attractions.
1.7. What is the pH of a 108 M solution of

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Retrieved Text: Cells must constantly generate energy to sustain life. The processes that produce and consume energy all make up cellular metabolism. Metabolism includes all chemical reactions that occur according to the laws of thermodynamics. Animals obtain energy from consuming organic molecules and breaking them down to release the energy stored within their chemical bonds. Energy is generated via cellular respiration through three major pathways: glycolysis, the citric acid cycle, and oxidative phosphorylation. Through a series of exothermic reactions, these pathways release energy in the form of ATP, which can be used to power biosynthesis.
In a series of steps, energy is released from food and used to drive the reactions that build the molecules cells need.
Free energy change can be used to predict whether a chemical reaction will occur spontaneously.
Enzymes degrade the carbohydrates, proteins, and lipids in food into simple subunits that will be further broken down either in glycolysis or in the citric acid cycle.
During glycolysis, glucose is oxidized to pyruvate.
The first phase of glycolysis is called "energy investing" because energy is required to form fructose from glucose.
The second phase of glycolysis is called "energy harvesting" because energy in the form of ATP and NADH is produced.
Pyruvate is oxidized to form acetyl-CoA, which enters the citric acid cycle to produce ATP, electron carriers, and CO2 as a waste product.
During oxidative phosphorylation, the oxidation of electron carriers is coupled to the phosphorylation of ADP to produce most of the ATP made by the cell.

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Retrieved Text: D. None of the choices are correct.
ASM Objective: 03.02 The interactions of microorganisms among themselves and with their environment are determined by their metabolic abilities (e.g., quorum sensing, oxygen consumption, nitrogen transformations).
ASM Objective: 03.03 The survival and growth of any microorganism in a given environment depends on its metabolic characteristics.
2. Although most metabolic reactions are freely reversible, a few irreversible catabolic steps are bypassed during biosynthesis with special enzymes that catalyze the reverse reaction in order to allow for independent regulation of catabolic and anabolic pathways.
3. Metabolic pathways can be either catabolic or anabolic but not both.
4. __________ pathways are those that function both catabolically and anabolically.
5. The catabolism of glucose begins with one or more of the glycolytic pathways that yield pyruvate.
6. ____________ ____________ is a process that can completely catabolize an organic energy source to CO2 using the glycolytic pathways and TCA cycle with O2 as the terminal electron acceptor for an electron transport chain.
7. Very few Gram-positive bacteria utilize the Entner-Doudoroff glycolytic pathway.
8. Some aerobic bacteria lack the Entner-Doudoroff and Embden-Meyerhoff pathways and instead use the pentose phosphate pathway for glycolysis.
9. An organism may use glycolysis and the pentose phosphate pathway simultaneously.
D. All of the choices are correct.
13. The synthesis of ATP from ADP and Pi, when coupled with an exergonic chemical reaction is called __________ phosphorylation.
D. two ATP or GTP molecules.
17. After glycolysis, pyruvate is oxidized to one CO2 and the two-carbon molecule acetyl-CoA by a multienzyme system called the ________ ________ complex.
18. TCA cycle enzymes are found in the _____________ _________

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Retrieved Text: Different types of alcohol can be produced solely after fermentation as well as if you love your own heady beverages then you should understand the importance of aerobic fermentation in alcoholic beverage manufacturing destilerijski-kvasac.com. Fermentation turns sugar contained in the actual mix of water and also various kinds of grains, fruits or vegetables straight into ethanol, generally referred to as alcohol, that is then additionally processed to create the required alcoholic beverage.
Ethanol fermentation can merely occur when the preliminary mixture is infused with brewing yeast. With modernization has come specialization and you may now come across various kinds of yeasts available in the market such as brewers yeast, distillers yeast, bakers yeast, vodka yeast, wine yeast, instant yeast, and many others. Although all sorts of yeast tend to be essentially unicellular fungi, these specific yeasts consist of distinct capabilities which result in excellent sugar fermentation during various degrees of yeast temperatures.
Aerobic fermentation or aerobic respiration utilizes oxygen to produce energy or Adenosine Triphosphate [ATP]. During alcoholic beverage production, this process takes place inside huge vats or tanks. Nevertheless, prior to actual fermentation, the process of glycolysis helps to ensure that two molecules of pyruvate are created out of every molecule of glucose. The aerobic respiration additionally oxidizes the pyruvate molecules and creates even more ATP. The particular fermentation of sugar results at ideally suited temperatures and also along with the correct quantity of oxygen results in the desired alcohol drinks which are then processed further more to get the end product together with the necessary strength

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Retrieved Text: What is Photosynthesis? How does it work? Get an insight into nature's most magnificent art with the help of flowchart!
This article will introduce the process of photosynthesis, how it works, and how to draw a flowchart to represent the workflow inside the plant when photosynthesis happens.
In other words, photosynthesis is the process when plants make their own food.
Photosynthesis has two phases, they are commonly known as "Photosynthesis Light Reaction" and "Photosynthesis Dark Reaction". We will analyze these two phases one by one.
This reaction of photosynthesis only happens when light is available. In this reaction the light hits the reaction centers of chlorophyll in the chloroplasts. The chlorophyll will vibrate, makes water molecule (H2O) and oxygen (O) released into air and the remaining molecules of hydrogen (H) from the water (H2O) remains in chloroplast and gets attached to NADP. In this phase of photosynthesis energy loses along the electron transport chain to recharge ATP from ADP. During this process, light energy gets converted into chemical energy and finally ATP molecules are produced. This reaction is also known as light-dependent reaction.
This phase of photosynthesis does not require light and it takes place in stroma. In this reaction the carbon dioxide (CO2) in the atmosphere combines with hydrogen (H) from water molecules and forms glucose. During this process, ATP molecules will be converted to simple sugars. This reaction is also known as light-independent reaction.
A flowchart is a way to show the steps in a process. Below is the flowchart of photosynthesis process that shows the steps involved in the

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Input Text: Answer the following question given this paragraph: 

The hypothalamus is actually part of the brain (see Figure below ), but it also secretes hormones . Some of its hormones “tell” the pituitary gland either to secrete or to stop secreting its hormones. In this way, the hypothalamus provides a link between the nervous and endocrine systems. The hypothalamus also produces hormones that directly regulate body processes. These hormones travel to the pituitary gland, which stores them until they are needed. The hormones include antidiuretic hormone and oxytocin.


Q: Which part of the brain secretes hormones that tell the pituitary gland either to secrete or to stop secreting its hormones?

 Choices:

- hippocampus

- cerebrum

- hypothalamus

- thalamus

A:

Target Text: hypothalamus

#### Retrieved Documents ####

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Retrieved Text: Metaglossary.com - Definitions for "gland"
An organ for secreting something to be used in, or eliminated from, the body; as, the sebaceous glands of the skin; the salivary glands of the mouth.
An organ or part which resembles a secreting, or true, gland, as the ductless, lymphatic, pineal, and pituitary glands, the functions of which are very imperfectly known.
A special organ of plants, usually minute and globular, which often secretes some kind of resinous, gummy, or aromatic product.
An organ producing a secretion.
a structure which contains or secretes a sticky, shiny, or oily substance.
Latin glans = an acorn, adjective - glandular; a secreting organ.
a cell or group of cells which secrete substances.
Glande Drüse, f Glándula On the tepals usually at the base, are found glands which secrete a generally sweet substance which attracts insects and thus aid in the pollination of the flowers.
Collection of cells that produces secretions or excretions of a specialized character.
Organ of the body that processes chemical substances in the blood to produce other chemical substances for use in the body or for elimination from the body. A gland may have ducts for pouring its secretions into other parts of the body, or it may be ductless and pour secretions into the bloodstream. The prostate is a ducted gland.
A secreting cell, or group of cells.
n. (L. glands, acorn) a secreting part or appendage.
An organ or group of cells that produces and secretes one or more substances.
a group of cells that secrete a substance for use in the body (eg, pituitary gland).
Glands are organs that secrete hormones.

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Retrieved Text: The pituitary is an endocrine gland located at the base of the brain that secretes a number of vital hormones.
The pituitary is an endocrine gland located at the base of the brain that secretes a number of vital hormones. Pituitary tumors are generally nonmalignant but may cause problems if they secrete excess hormones, inhibit hormones or compress areas of the surrounding brain.

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Retrieved Text: This test is vital to detect thyroid disorders and monitor the patient during the treatment of the hypo or hyperthyroidism. It measures the level of Thyroid Simulating Hormone (TSH) in the blood. The pituitary gland, which is attached to the base of the brain, secrets TSH. In addition it functions by stimulating the thyroid gland to secrete its hormones. The thyroid gland, located beneath the larynx, is the internal thermostat of the body that regulates temperature by secreting T4- Thyroxine and T3- Triiodothyronine hormones. These hormones control the speed of energy utilization. Testing for the levels of thyroid hormone T4 is recommended with this test.

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Retrieved Text: The keystone of acupuncture and Oriental medicine has always been awakening the body’s natural intelligence to heal itself and restore balance to the system of energy pathways (called “meridians”) that crisscross the body. If the meridians within your body have become depleted you can suffer from tiredness, infertility, weight gain, depression, digestive problems, hair loss, arthritis, and feeling chilled no matter the temperature.The endocrine system is responsible for hormonal functions in the body and produces thirty distinct hormones each of which has a very specific job to do. This system controls your physical growth, mood, hormone output, reproduction, mental functionality, and immune system. When not working properly you become more susceptible to disease and your ability to fight off infection is weakened. Endocrine glands and their functioning impacts every area of your health.
Adrenals – Adrenal glands regulate the body’s response to stress and are made of two parts, each of which secretes a separate set of hormones. The outer part produces corticosteroid hormones that regulate the balance of salt and water, stress response, metabolism, immune function, and sexual development and function. The inner part secretes adrenaline hormones that increase blood pressure and heart rate in response to stress. Over time chronic elevated stress levels can lead to weight gain, decreased resistance to infections, fatigue, muscle aches and low blood sugar.
Pancreas – The pancreas produces insulin and glucagon-two hormones that work together to supply the body’s cells with a constant supply of energy in the form of glucose.
Pineal – The pineal gland is also known as the

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Retrieved Text: The pituitary gland is divided into two main parts, the anterior and posterior lobes. The anterior pituitary consists of endocrine cells that synthesize and secrete hormones directly into the blood. The posterior pituitary is an extension of the hypothalamus. It stores and secretes two hormones that are made by a set of neurosecretory cells in the hypothalamus.
The posterior pituitary releases the hormones oxytocin—which acts on muscles of the uterus—and antidiuretic hormone (ADH), which acts on the kidneys. Oxytocin induces contraction of the uterine muscles during childbirth and causes mammary glands to eject milk during nursing. ADH acts on the kidneys, increasing water retention and thus decreasing urine volume.
The anterior pituitary produces six different hormones. Growth hormone affects a wide variety of tissues. The correct level of growth hormone production is essential, as too little or too much can have serious detrimental effects. Prolactin stimulates mammary gland growth and milk synthesis. Follicle stimulating hormone (FSH) stimulates production of ova and sperm, and luteinizing hormone (LH) stimulates the ovaries and testes. LH is needed for ovulation and the formation of a corpus luteum in the female menstrual cycle. LH also stimulates the testes to produce testosterone. FSH and LH are referred to as gonadotropins because they stimulate the activities of the gonads. Thyroid-stimulating hormone, stimulates the thyroid gland to produce thyroxine. Adenocorticotropic hormone influences the adrenal cortex to produce and secrete steroid hormones.
SEER Training Modules: Pituitary and Pineal Glands. Illustration courtesy of the National Cancer Institute, NIH.

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Retrieved Text: The pituitary gland, also known as the hypophysis, is a small, pea-sized gland located at the base of our brains. It is commonly referred to as the “master gland” of the human body, as it releases a variety of hormones that circulate our system and aid in maintaining our internal homeostasis. Moreover, the pituitary gland is also the “master” or dominant gland controlling the activity of other glands. The pituitary gland is responsible for producing and storing an assortment of important hormones that we will discuss in more detail.
The main function of the pituitary gland lies in its ability to make hormones that retain many of our bodily functions. The front (anterior) and back (posterior) lobes are the primary secretory glands. These glands are innervated by the nervous system. The pituitary gland also responds to signals within the extracellular fluid, such as the amount of dissolved solvent or other hormones.
By responding to these signals and releasing the appropriate hormones, the pituitary gland plays a large role in coordinating many aspects of the body including metabolism, digestion, excretion, and many other factors. The pituitary gland releases at least 8 different hormones, which are responses to different stimulations of the gland. The pituitary gland is one of the most active glands within the endocrine system.
The image below is an illustration of the pituitary gland as it is situated near the base of the human brain. The depiction shows its relative size.
The pituitary gland lies roughly in the center of the human skull. It rests below the hypothalamus of

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Retrieved Text: Hyperpituitarism is defined to mean too much of one, or perhaps two, of the hormones from the adenohypophysis. This may be due either to autonomous over-production (i.e., from a primary adenoma in this gland [microadenoma, macroadenoma] – cancer of the adenohypophysis is very rare Cancer 79: 804, 1997, J. Neurosurg. 96: 352, 2002), from excess production of hypophyseal stimulating factors or underproduction of inhibiting factors, or loss of inhibition following the destruction of other endocrine glands.
Pituitary disease, like other endocrine disease, is fairly common, and is generally treatable if it is discovered. The anterior pituitary (adenohypophysis), produces ACTH, TSH, FSH, LH, GH, and prolactin. If the input from the hypothalamus is interrupted, the adenohypophysis makes more prolactin and less of the other hormones.
The presenting clinical symptoms are due exclusively to overproduction of those hormones normally secreted. The characteristic syndromes are related to the type of hormone secreted. Prolactinomas produce amenorrhoea / galactorrhoea in women and impotence / gynecomastia in men; ACTH secreting tumors produce Cushing’s syndrome; growth hormone secreting tumors produce gigantism in children and acromegaly in adults.
Diagnosis is usually made by MRI since the CAT scans are of poorer resolution. Most patients will be treated with drugs, surgery or radiation.
Pituitary adenomas cause most cases of Cushing’s syndrome. They are non-cancerous tumors of the pituitary gland which secrete increased amounts of ACTH. Most patients have a single adenoma. This form of the syndrome, known as “Cushing’s disease,” affects women five times more frequently than men.
Occurs when the male breast is enlarged. The size can vary from

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Retrieved Text: Hormones work on maintaining the homeostasis of the internal environment in the human body through a mechanism called Feed mechanism , similarly , The Thermostat of different domestic makes machines start or stop working at a specific temperature ( It maintains the balance of machine working ) .
Feedback mechanism is a mechanism with which hormones act to achieve the homeostasis in the human body , There are applications showing how hormones maintain the human body homeostasis through the feedback mechanism .
Insulin hormone and glucagon hormone play an important role in homeostasis the level of glucose sugar in the blood .
On increasing the level of glucose sugar in the blood than its normal level , The pancreas responses by secreting insulin hormone which stores glucose sugar that increases in the body in the liver and it stimulates the body cells to absorb glucose from the blood .
On decreasing the level of glucose sugar in the blood than its normal level , The pancreas responses by secreting glucagon hormone which affects the liver to increase the conversion rate of glycogen stored inside it into glucose sugar to increase the level of glucose sugar in the blood until it reaches the normal level .
When the pancreas decreases its secretion of insulin hormone , The level of glucose sugar in the blood increases or the human suffers from diabetes disease .
What is Feedback mechanism to balance thyroxin hormone level in the blood ?
You should know that the thyroid gland and the pituitary gland have an important role in homeostasis the

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Retrieved Text: Central nervous system. Computer artwork showing the brain, cranial nerves and the top portion of the spinal cord. At centre is the pituitary gland (small, spherical), which secretes hormones. Either side of it are the optic nerves (yellow), with the olfactory nerves (yellow) above it. Beneath the pituitary gland is the brainstem, which controls automatic functions, sleep and arousal and relays messages from the brain to the spinal cord. The striped structure either side of the brainstem is the cerebellum, which controls muscle coordination and balance.

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Retrieved Text: The thyroid is a soft, butterfly-shaped gland that lies wrapped around the windpipe below the Adam's apple. Its job is to secrete thyroid hormones that help regulate metabolism - in other words, the many chemical processes that keep our bodies ticking over.
The thyroid gland manufactures two essential hormones – thyroxine (also referred to as T4) and triiodothyronine (also referred to as T3). In normal health most T3 circulating in the blood stream has been converted from T4. Both T4 and T3 have the same action on cells of the body but T3 is more potent. T4 mostly functions as a reserve for T3. Together these two similar hormones are called thyroid hormone.
Thyroid hormone regulates the metabolic rate of almost all the cells of the body, and influences the health of the heart, brain and bones. It is also needed for normal development of the brain in children and for normal reproductive functioning.
In Australia there are about 60,000 new cases of thyroid disease each year. Some people have a problem with how the gland functions: it may produce too much or too little thyroid hormone. Others have problems with the structure of the gland itself, where it becomes enlarged, lumpy, and/or inflamed.
When the gland is healthy, it releases as much thyroid hormone as we need to keep our metabolism on an even keel. It knows just how much to release because of the feedback loop between a gland in the base of the brain, called the pituitary, and the thyroid itself. To function normally, the pituitary also

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Retrieved Text: Growth hormone deficiency or GHD takes place when the pituitary gland doesn’t secrete much growth hormone on its own. It affects the children more as compared to adults. The pituitary gland is a small pea shaped gland that is located at the base of the brain and that secretes 8 hormones. Some of the hormones control body temperature and thyroid function while HGH controls your body growth and development.
This deficiency occurs in about 1 person per 7000 births. The condition is a symptom of various genetic problems like Prader Willi syndrome and Turner syndrome. You may get concerned if your child doesn’t meet the weight-height growth standards. The best part about this is that GHD is treatable.
Children who are diagnosed early can recover fast and well. And if left untreated, this condition may lead to shorter than average height as well as delayed puberty. Your body requires GH after puberty. And once you get into the phase of adulthood, GH maintains the overall body structure and metabolism.
GHD is caused by low or no secretion of growth hormones by the pituitary gland. This may be due to congenital or acquired problems. Congenital GHD may be linked with abnormal pituitary gland or may even be a part of another syndrome. In case of normal aging procedure, there is a reduction in amount of GH secreted every day and in its pattern of secretion. It is not sure if this is clinically vital or requires any extra administration. On the other hand, acquired causes behind HGH deficiency include brain

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Retrieved Text: There exists a unique relationship between IGF-1 and growth hormone with both a stimulatory and mediating effect. The growth hormone/IGF-1 axis involves the hypothalamus, pituitary gland, and liver.
We see this function occur in most bodily tissues, especially in the bones and muscles.
IGF-1 mediates many of the metabolic effects of circulating GH. Are IGF-1 and HGH the same type of hormones since they work in unison?
Not really, as they have functions that are also unique unto themselves. While IGF-1 does mediate many of the processes of GH, it also carries out some features of its own, such as the stimulation of nitric oxide which aid circulation.
IGF-1 and HGH together accomplish quite a bit just in the role of supplying all areas of the body with new cells. As old cells die off, they require new ones to take their place. When GH levels decline, cell proliferation decreases. That is why internal organs shrink, muscles lose their tone, bones become brittle, and skin and hair get thinner with age. Wrinkles, gray hair, sagging skin, and hair loss are all signs that GH and IGF-1 levels have started to decline.
How Does Growth Hormone Regulate IGF-1?
The relationship between IGF-1 and growth hormone begins with GH promoting the production of insulin growth factor 1. It is a complicated process that requires numerous hormones working at maximum potential to complete the feedback loop.
The balance of IGF-1 and HGH in the bloodstream begins with the hypothalamus. Here, a determination is made as to whether the body requires a supply of GH at any

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Retrieved Text: There is no secret that today the in vitro fertilization intervention is the most effective in lab method that can give families with no children the chance to become parents and have kids. If we should talk about the factors that can cause infertility both in men and women then you should know that the list can be endless starting with a wrong diet, smoking and alcohol abuse and ending with physical disorders associated to different tumors, cancers or hypophysis malfunction.
If you don’t know pretty much about the way the pituitary gland affects your fertility you should stick around for a couple of minutes in order to read more about its role in the reproductive system functioning.
The first thing you should hear about is that the pituitary gland is located at the base of your brain and it has a pea dimensioned aspect. But regardless its size, this gland has a major endocrine role. You should know it performs many roles in secreting the growth hormone, the thyroid stimulating hormone, the luteinizing hormone and very important the follicle stimulating hormones.
You should know that secreting the follicle stimulating hormones the hypophysis has a very important role in ensuring a female fertility. Not to mention that the ovulation process is directly tied to the activity of these hormones. The follicle stimulating hormones are necessary for the ovarian follicle maturation. The reproductive process is regulated by these hormones and in many cases associated to infertility when the cause can be found in the lack of secreting these hormones. You

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Retrieved Text: Measuring thyroid stimulating hormone (TSH) is useful in assessing thyroid function and monitoring patients undergoing thyroid replacement therapy. The Access TSH (3rd IS) assay can help you provide physicians and their patients with reliable, accurate results for each test, every time.
TSH is part of the hypothalamic-pituitary-thyroid axis that regulates the body’s metabolism. The hypothalamus secretes a thyrotropin-releasing hormone (TRH), stimulating the pituitary gland to secrete TSH. TSH causes the release of thyroid hormones, T3 (triiodothyronine) and T4 (thyroxine), which control metabolic functions within the cells. When excessive amounts of T3 or T4 circulate, production of TRH stops, resulting in the process being controlled by a negative feedback loop.
The Access TSH (3rd IS) assay provides adherence to the highest industry standards.
The Access TSH (3rd IS) assay ensures less hands-on time in the laboratory.
The Access TSH (3rd IS) assay provides high functional sensitivity and precision.

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Retrieved Text: Hypothalamus. The hypothalamus is located at the base of the brain, near the optic chiasm ﻿﻿﻿where the optic nerves behind each eye cross and meet. ﻿The hypothalamus secretes hormones that stimulate or suppress the release of hormones in the pituitary gland, in addition to controlling water balance, sleep, temperature, appetite, and blood pressure.
Pineal body. The pineal body is located below the corpus callosum, in the middle of the brain. It produces the hormone melatonin, which helps the body know when it's time to sleep.
Pituitary. The pituitary gland is located below the brain. Usually no larger than a pea, the gland controls many functions of the other endocrine glands.
Thyroid and parathyroid. The thyroid gland and parathyroid glands are located in front of the neck, below the larynx (voice box). The thyroid plays an important role in the body's metabolism. The parathyroid glands play an important role in the regulation of the body's calcium balance.
Thymus. The thymus is located in the upper part of the chest and produces white blood cells that fight infections and destroy abnormal cells.
Adrenal gland. An adrenal gland is located on top of each kidney. Like many glands, the adrenal glands work hand-in-hand with the hypothalamus and pituitary gland. The adrenal glands make and release corticosteroid hormones and epinephrine that maintain blood pressure and regulate metabolism.
Pancreas. The pancreas is located across the back of the abdomen, behind the stomach. The pancreas plays a role in digestion, as well as hormone production. Hormones produced by the pancreas include insulin and glucagon, which regulate levels of

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Retrieved Text: Your thyroid gland is a small gland, normally weighing less than one ounce, located in the front of the neck. It is made up of two halves, called lobes, that lie along the windpipe (trachea) and are joined together by a narrow band of thyroid tissue, known as the isthmus.
The thyroid is situated just below your "Adams apple" or larynx. During development (inside the womb) the thyroid gland originates in the back of the tongue, but it normally migrates to the front of the neck before birth. Sometimes it fails to migrate properly and is located high in the neck or even in the back of the tongue (lingual thyroid). This is very rare. At other times it may migrate too far and ends up in the chest (this is also rare).
The function of the thyroid gland is to take iodine, found in many foods, and convert it into thyroid hormones: thyroxine (T4) and triiodothyronine (T3). Thyroid cells are the only cells in the body which can absorb iodine. These cells combine iodine and the amino acid tyrosine to make T3 and T4. T3 and T4 are then released into the blood stream and are transported throughout the body where they control metabolism (conversion of oxygen and calories to energy).
Every cell in the body depends upon thyroid hormones for regulation of their metabolism. The normal thyroid gland produces about 80% T4 and about 20% T3, however, T3 possesses about four times the hormone "strength" as T4.
The thyroid gland is under the control of the pituitary gland,

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Retrieved Text: Hypothyroidism is a condition resulting from an underactive thyroid gland, which is associated with an undersupply of hormones that control metabolism in the body.
The thyroid gland plays a key role in the endocrine system, which produces the hormones that control bodily functions such as metabolism. If the hormone levels are not within a normal range, this can affect the whole body, causing a wide range of symptoms and health problems.
The thyroid is located at the front of the throat, just above the hollow between the upper ends of the collarbones and below the Adam's apple (the larynx). It has two lobes that sit on either side of the windpipe. It is controlled by the pituitary gland, which sits at the base of the brain and secretes thyroid-stimulating hormone (TSH).
The thyroid hormones circulate throughout the bloodstream, regulating metabolism. The lower the levels of T3 and T4 are, the slower metabolism will be.
Low levels of T3 and T4 in the bloodstream are detected by the pituitary gland, which then secretes more TSH to try to stimulate the thyroid gland to produce more thyroid hormones.
Thyroid-stimulating hormone stimulates the thyroid gland to produce metabolism-regulating hormones T3 and T4.
Hypothyroidism can affect the whole body and the symptoms can vary greatly between people. Symptoms may develop suddenly, or very slowly over years. They may be so slight that they are difficult to notice, or so severe they are life-threatening. In older people, symptoms can be difficult to tell apart from the normal changes that come with ageing.
Because hypothyroidism causes a slowing of

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Retrieved Text: ...and what does it do?
Your pituitary gland is about the size of a pea and is situated in a bony hollow, just behind the bridge of your nose. It is attached to the base of your brain by a thin stalk.
The hypothalamus, which controls the pituitary by sending messages, is situated immediately above the pituitary gland.
The pituitary gland is often called the master gland because it controls several other hormone glands in your body, including the thyroid and adrenals, the ovaries and testicles.
It secretes hormones from both the front part (anterior) and the back part (posterior) of the gland. Hormones are chemicals that carry messages from one cell to another through your bloodstream.
If your pituitary gland is not producing sufficient amounts of one or more hormones this is called hypopituitarism.
If on the other hand you are over producing certain hormones, then you would have features due to the over production of the specific hormone concerned.
This serves as a communications centre for the pituitary gland, by sending messages or signals to the pituitary in the form of hormones which travel via the bloodstream and nerves down the pituitary stalk. These signals, in turn, control the production and release of further hormones from the pituitary gland which signal other glands and organs in the body.
The hypothalamus influences the functions of temperature regulation, food intake, thirst and water intake, sleep and wake patterns, emotional behaviour and memory.
The most common problem with the pituitary gland occurs when a benign tumour (used to describe a ‘growth’), also called an adenoma, develops.
Pituitary

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Retrieved Text: We never really think about the importance of Hormones and the contribution to total body function and optimal health. There are several hormones functioning in the body that regulate growth, metabolism and sexual development. ip address information The Endocrine system is responsible for these hormones including the thyroid, adrenal, pituitary and hypothalamus glands. These glands release hormones into the bloodstream which then are transported to the organs and tissues throughout the entire body.
The thyroid gland is responsible for fat metabolism and the parathyroid gland which is embedded in the thyroid gland controls the levels of calcium in the blood. The thyroid gland secretes hormones which regulate energy and emotional balance and controls basal metabolism and body temperature. Weight gain is usually in the midsection.
The adrenal gland is responsible for how energy in the body is stored and how food is used. The adrenal gland is part of the sympathetic nervous system and it’s the body’s first line of defense in response to physical and emotional stress, the “fight” or “flight” mechanism. The hormones secreted are in direct response to the pituitary hormone ACTH. This hormone is a steroid called Cortisol and under prolonged stress will promote health challenges including chronic pain, chronic inflammation or infection, emotional response, glycemic (sugar) problems, immune dysfunction and the inability to release growth hormones. The adrenal gland controls weight in the thigh and knee area.
The pituitary gland is an important link between the Central Nervous System (CNS) and the Endocrine System (ES) and is responsible for the release of growth hormones,

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Retrieved Text: Adrenocorticotropic hormone (also known as "ACTH") is a pituitary hormone. A hormone is a chemical produced by a gland. The pituitary gland, located below the brain, secretes (releases) several hormones that control other glands which regulate growth and metabolism. ACTH's principal function is to stimulate the cortex (outer layer) of the adrenal glands (located near the kidneys) to secrete a group of steroid hormones called glucocorticoids. Glucocorticoid hormones control the body's use of sugar and also help regulate biological functions during stressful moments.
The properties of ACTH were first investigated in the 1930s. In 1933 research groups headed by Canadian biochemist James Collip, American biologist Herbert Evans (1881-1971), and Argentine physiologist Bemardo Houssay (1887-1971) used pituitary extracts to stimulate the adrenal cortex (the center of the adrenal glands). American biochemist Choh Hao Li was one of several scientists who isolated ACTH in 1943 and synthesized it in 1963.
Today, ACTH is often prescribed to reduce inflammation (tenderness and swelling caused by infection, injury, or illness) and relieve pain. This use of ACTH was first studied by American medical researchers Philip Hench (1896-1965) and Edward Kendall (1886-1972), who were looking for an effective treatment for arthritis. During World War II (1939-1945) Hench headed the first program to mass-produce ACTH for medical use. In 1948 and 1949 Hench and another colleague were the first researchers to use ACTH successfully in arthritic patients. Hench and Kendall received the 1950 Nobel Prize in physiology or medicine for their achievement.
ACTH is commonly used to reduce inflammation in rheumatoid arthritis (a disabling inflammation of

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Retrieved Text: The pituitary gland consists of two separate glands: the anterior pituitary and the posterior pituitary.
The purpose of this paper is to detail the role of the pituitary gland in the regulation of other hormones in the body. In your essay, provide a brief overview of the anatomy of the pituitary gland.
Describe the hormones that are released from each gland; explain what triggers the release of hormones; identify characteristics that they have in common; and classify which hormones are considered tropic hormones.
Summarize your information by explaining why the pituitary gland is commonly referred to as the “master gland,” and in what sense this may be misleading and incorrect.
Your cohesive and well-organized essay should be at least 1-2 pages in length, double spaced.
Include at least one scholarly reference in addition to the course textbook. The CSU-Global Library is a good place to find these references.
Include a title page and a references page.
Follow the CSU-Global Guide to Writing and APA.
The pituitary gland, which is also referred to as hypophysis, is a pea-sized endocrine gland weighing approximately 0.5 grams that are located below the hypothalamus gland, which synthesizes and/or secretes hormones that help regulate blood pressure, growth, metabolism, among other functions. It is surrounded by a bony cavity referred to as the sella turcica. Notably, the gland has two lobes which produce hormones, namely the posterior and anterior lobes. The posterior lobe that is also known as the neurohypophysis, while the anterior lobe is also known as adenohypophysis. The anterior pituitary lobe synthesizes various hormones in its different cell types.

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Retrieved Text: Get the toxins and waste products out from the cells (this is a balanced elimination system).
Then you can heal from any symptom, condition or disease. ANY of them!
Balance the Hormonal System Naturally.
Your hormonal system is what carries the nervous system information to the actual organs, glands, tissues and cells of the body. It is the brain/body communication.
Pituitary- master control of the hormonal system. It is a part of the critical HPA axis- Hypothalamus in the brain is the sensor or thermostat reading the internal environment. When is senses a change is necessary it sends messages to the pituitary which then send messages out to the rest of the hormonal glands.
Pineal- controls sleep and immune function.
Thyroid- this is your furnace of your metabolism that runs you. Low fire=low enzyme activity=low health and vitality.
Thymus-this is the heart of your immune system.
Pancreas- this is your digestion source and blood sugar control center.
Adrenals- this is where energy and immunity begin.
Female/Male hormones- energy and vitality but not artificially induced or else you will have to pay the price.
Melatonin – balances your immune system and metabolism (to keep the fire burning so all enzymes and metabolic pathway perform to perfection) – this is all controlled by light and dark cycles.
Insulin control brain chemistry and dopamine and serotonin levels that in turn affect your behavior and mood.
When one goes out of balance they all go out of balance.
Melatonin affects the pituitary gland function.
Pancreas – blood sugar, appetite, immune function.
Adrenals – stress management, pain control, immune function.
In the order of endocrine command, the hypothalamus

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Retrieved Text: Living Stream Whole Pituitary Glandular raw material is collected from bovine animals that are born and raised in Argentina. All raw materials were derived from animals that passed ante and post-mortem veterinary inspection and were found fit for human consumption. The cattle from which the glands are derived, are free range and fed only with natural grass. The product is manufactured in a certified Kosher gelatin capsule.
Glandulars used in proper doses have not been found to be harmful to the body.
The pituitary gland is considered the "Master Gland" and the most important part of the endocrine system and has the responsibility of directing other organs and endocrine glands to suppress or secrete hormones.
There is a relationship between the Hypothalmus-Pituitary-Adrenal Axsis. This HPA axsis, regulates temperature, digestion, immune system, mood, sexuality, energy useage and response to stress. Deficient Pituitary gland function can result from damage to either the Pituitary or the Hypothalmus.

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Retrieved Text: The hormones of the pituitary gland help regulate the functions of other endocrine glands.
The pituitary gland has two parts—the anterior lobe and posterior lobe—that have two very separate functions.
The hypothalamus sends signals to the pituitary to release or inhibit pituitary hormone production.
The pituitary gland is often dubbed the “master gland” because its hormones control other parts of the endocrine system, namely the thyroid gland, adrenal glands, ovaries, and testes. However, the pituitary doesn’t entirely run the show.
In some cases, the hypothalamus signals the pituitary gland to stimulate or inhibit hormone production. Essentially, the pituitary acts after the hypothalamus prompts it.
The pituitary gland is only about 1/3 of an inch in diameter (that’s about as large as a pea) and located at the base of the brain.
Since their functions are so intertwined, it’s no surprise that the hypothalamus and pituitary are located near each other. They’re actually connected by the pituitary stalk, or more technically, the infundibulum.
The pituitary glands are made of the anterior lobe and posterior lobe. The anterior lobe produces and releases hormones. The posterior lobe does not produce hormones per se—this is done by nerve cells in the hypothalamus—but it does release them into the circulation.
The hormones of the pituitary gland send signals to other endocrine glands to stimulate or inhibit their own hormone production. For example, the anterior pituitary lobe will release adrenocorticotropic hormone (ACTH) to stimulate cortisol production in the adrenal glands when you’re stressed.
The anterior lobe releases hormones upon receiving releasing or inhibiting hormones from the hypothalamus. These hypothalamic hormones tell

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Retrieved Text: functions. Looking at these functions, it is obvious that thyroid is one of the important parts of the body.
TSH (thyroid stimulating hormone) produced by the pituitary gland tells you when to produce thyroid hormones (T3 and T4) in your brain. This thermostat is similar to adjusting the heating systems according to room temperature. Patients complaining of low TSH usually have high T3 / T4 hormone levels. Since low TSH levels are often associated with hyperthyroidism (overwork of the thyroid gland) that causes other symptoms, it is important to take TSH to normal and to prevent it from falling again if necessary.
What Does TSH Loss Mean?
Your secretory glands are not producing enough.Your thyroid gland is overworked, producing too much thyroid hormone, which sends a signal to your brain to stop production.Individuals complaining of low levels of TSH and high levels of T3 and T4 (thyroid hormones) have a condition known as hyperthyroidism. However, if an individual suffers from both low TSH levels and low thyroid hormones, this can be due to the weak, diseased or damaged pituitary gland responsible for thyroid production.
The pituitary gland may suffer from severe head injury or, more rarely, from tumor. The pituitary gland produces not only thyroid hormones, but also 8 different hormones. A simple blood test can be used to determine whether the level of hormones produced by the pituitary gland in the body is normal. Alternatively, some patients may be able to see if the pituitary gland is damaged by pulling a brain film to make sure it is not

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Retrieved Text: The pituitary gland is a small pea-shaped endocrine gland that is located at the base of the brain. It regulates homeostasis by secreting necessary hormones into the body. It helps our body react to senses and the environment. For a detailed description of the pituitary gland go here. In energy medicine, the pituitary gland is connected to the 6th chakra and is sometimes referred to as the third eye.
Emotionally individuals with pituitary gland imbalances often feel confused or scatter-brained and may have trouble concentrating. They may feel a lack of connection to the earth or their own body. This may be caused by some past trauma or a lack of connection to a caregiver or parent during their first few years. Where the pineal gland is our connection to the spiritual, the pituitary gland is our connection to the physical.
What can I do to help the pituitary gland function correctly?
- Apply Deep Blue or another oil containing menthol to the brow. Make sure not to get into the eyes.
- Work the pituitary gland reflex point on the foot.
- Attend a class or learn a new skill that interests you.
- Wear the color indigo.
- Participate in a yoga class or do yoga poses at home.
- Make sure you are eating enough protein and that you are consuming foods high in protein, magnesium and vitamins E and D.

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Retrieved Text: Grab my FREE ebook to learn how lifestyle choices can balance your hormones and help with perimenopause and menopause. Click the image below to start the download.
Menopause is where you transition from the child-bearing years into permanent infertility. Although that sounds somewhat daunting, it is a natural progression. It brings on new beginnings that aren’t negative as the term seems to imply in our society today. More on this topic later.
Back to the more complex things I mentioned at the beginning. Menopause has stages which are subtle and can be different from woman to woman. Perimenopause defined as “around” menopause, is a stage. Menopausal symptoms usually begin at this point. Symptoms usually include changes in the menstrual cycle. You may know what I’m talking about. For instance, you go a month without your period or you may have period back-to-back.
This stage can start at any time, but is most common in your 40’s. Premature or early menopause is the cessation of menses (your period) before to age 40. This early menopause is a little uncommon but not worrisome because everyone is unique.
Many women wonder “When am I done with menopause?” The answer is that it is different for everyone. Some women experience minor symptoms for a short time and others experience symptoms into their 80’s and beyond.
It is interesting, many women think that hot flashes are the only symptoms of menopause. If they do not experience these hellfire moments they feel somehow lucky. They’ve escaped the horrible things that their girlfriends are talking about. But, these

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Retrieved Text: Today,� we are looking at how the Chinese treat thyroid disease. The focus is on balancing�the whole body with�no surgery or RAI involved.
The thyroid is a small butterfly-shaped gland on the front of the neck that sits just below the Adam�s apple and wraps around the windpipe (trachea). It is responsible for secreting the hormones necessary for growth and metabolism, and a regulator of all body functions. There are many types of thyroid disease; however, the main conditions present in most thyroid illnesses are hyperthyroidism (thyroid over-activity) and hypothyroidism (thyroid under-activity).
The thyroid itself is regulated by another gland located in the brain, called the pituitary. In turn, the pituitary is regulated in part by the circulating thyroid hormones and by another gland called the hypothalamus. The hypothalamus releases a hormone, which sends a signal to the pituitary gland to release thyroid stimulating hormone (TSH). In turn, TSH sends a signal to the thyroid to release thyroid hormones. If over activity of any of these three glands occurs, an excessive amount of thyroid hormones can be produced, thereby resulting in hyperthyroidism. Similarly, if under activity of any of these glands occurs, a deficiency of thyroid hormones can result, causing hypothyroidism.
Hypothyroidism can also be classified as primary or secondary. Primary hypothyroidism is thought of as an autoimmune disease induced through chronic inflammation of the thyroid gland, also known as Hashimoto�s thyroiditis. This variety occurs most commonly in women. Secondary hypothyroidism is caused by failure of the hypothalamus to regulate the thyroid gland, or lack of secretion of TSH

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Retrieved Text: All endocrine structures develops from epithelia or nervous tissues, or from both. It is noteworthy that some structures described here have other important functions, e.g., kidney, gonads, pancreas.
The Hypothalami are paired thickenings in the thalamencephalon and thus nervous in origin. They control most of the endocrine structure, acting through the pituitary and autonomic systems. Groups of cells produce neurosecretions; droplets produced in cells traverse the axons into the pars nervosa, to be stored and later released into the blood. Other neurosecretions (releasing factors) pass in the blood of the hypothalamo – hypophyseal portal system into the pars anterior where they stimulate production of other hormones. Two hormones plus a number of releasing factors are produced. Oxytocin stimulates contractions of the uterus during birth, and promotes secretion of milk during suckling. Vasopressin causes a rise in blood – pressure by contraction of arterioles, and is also anti – diuretic, favoring resorption of water and Na+ ions from the renal tubules. Specific releasing factors affect the secretion of all hormones produced in the pars anterior and pars intermedia.
The Pituitary Body is an endocrine structure that lies beneath the thalamencephalon. It is formed by fusion of a hollow down – growth from the brain, the infundibulum, with a dorsal invagination from the stomodaeum, the hypophysis, and is thus nervous and epithelial in origin. The infundibulum becomes the pars nervosa; the endocrine parts of the hypophysis are the pars anterior and pars intermedia. The former secrets six hormones. Somatotropin (STH or growth hormone) stimulates rate of protein synthesis, excess producing

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Retrieved Text: Pituitary gland: The main endocrine gland. It is a small structure in the head. It is called the master gland because it produces hormones that control other glands and many body functions including growth. The pituitary consists of the anterior and posterior pituitary.
The anterior pituitary is the front portion of the pituitary. Hormones secreted by it influence growth, sexual development, skin pigmentation, thyroid function, and adrenocortical function. These influences are exerted through the effects of pituitary hormones on other endocrine glands except for growth hormone which acts directly on cells.
The posterior pituitary is the back portion of the pituitary. It secretes the hormone oxytocin which increases uterine contractions and antidiuretic hormone (ADH) which increases reabsorption of water by the tubules of the kidney. Underproduction of ADH results in a disorder called diabetes insipidus characterized by inability to concentrate the urine and, consequently, excess urination leading potentially to dehydration. The urine is "insipid" (overly dilute).

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Input Text: Answer the following question given this paragraph: 

Control of Catabolic Pathways Enzymes, proteins, electron carriers, and pumps that play roles in glycolysis, the citric acid cycle, and the electron transport chain tend to catalyze non-reversible reactions. In other words, if the initial reaction takes place, the pathway is committed to proceeding with the remaining reactions. Whether a particular enzyme activity is released depends upon the energy needs of the cell (as reflected by the levels of ATP, ADP, and AMP). Glycolysis The control of glycolysis begins with the first enzyme in the pathway, hexokinase (Figure 7.19). This enzyme catalyzes the phosphorylation of glucose, which helps to prepare the compound for cleavage in a later step. The presence of the negatively charged phosphate in the molecule also prevents the sugar from leaving the cell. When hexokinase is inhibited, glucose diffuses out of the cell and does not become a substrate for the respiration pathways in that tissue. The product of the hexokinase reaction is glucose-6-phosphate, which accumulates when a later enzyme, phosphofructokinase, is inhibited.


Q: Enzymes, proteins, electron carriers, and pumps that play roles in glycolysis, the citric acid cycle, and the electron transport chain tend to catalyze reactions that are what?

 Choices:

- changeable

- continuous

- reversible

- non-reversible

A:

Target Text: non-reversible

#### Retrieved Documents ####

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Retrieved Text: Cells must constantly generate energy to sustain life. The processes that produce and consume energy all make up cellular metabolism. Metabolism includes all chemical reactions that occur according to the laws of thermodynamics. Animals obtain energy from consuming organic molecules and breaking them down to release the energy stored within their chemical bonds. Energy is generated via cellular respiration through three major pathways: glycolysis, the citric acid cycle, and oxidative phosphorylation. Through a series of exothermic reactions, these pathways release energy in the form of ATP, which can be used to power biosynthesis.
In a series of steps, energy is released from food and used to drive the reactions that build the molecules cells need.
Free energy change can be used to predict whether a chemical reaction will occur spontaneously.
Enzymes degrade the carbohydrates, proteins, and lipids in food into simple subunits that will be further broken down either in glycolysis or in the citric acid cycle.
During glycolysis, glucose is oxidized to pyruvate.
The first phase of glycolysis is called "energy investing" because energy is required to form fructose from glucose.
The second phase of glycolysis is called "energy harvesting" because energy in the form of ATP and NADH is produced.
Pyruvate is oxidized to form acetyl-CoA, which enters the citric acid cycle to produce ATP, electron carriers, and CO2 as a waste product.
During oxidative phosphorylation, the oxidation of electron carriers is coupled to the phosphorylation of ADP to produce most of the ATP made by the cell.

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Retrieved Text: After completing this class, students should be able to: • Analyze the structure and physico-chemical properties of amino acids. • Describe in detail all four levels of protein structure. • Discuss the relationship between structure and function (or malfunction) in proteins providing a wide variety of examples. • Illustrate the principles involved in enzymatic catalysis, inhibition and kinetics from both an energetic and a structural standpoint, and apply those principles to a variety of problems. • Delineate the structure, chemical properties and function of relevant carbohydrates. • Describe metabolism in terms of nutrition, high-energy compounds, and thermodynamics concepts. • Delineate glycolysis, glycogen metabolism, the citric acid cycle and the electron transport chain in full stepwise detail including the reactions, the corresponding enzymes and their regulation. • Discuss organ specialization and regulation at the hormonal level of the different metabolic pathways. • Compare and contrast the sequence of reactions that take place during photosynthesis (for plants and cyanobacteria) with the electron transport chain.

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Retrieved Text: *At this point in the cycle, the hydrogen carrier is FAD (flavine adenine dinucleotide).
Chemical reactions of the citric acid cycle. NADH molecules carrying hydrogens are highlighted.
Figure 4.12, shows that NADH can release the electrons and hydrogen nucleus. Since this reaction removes electrons, the resulting NAD+ is said to be oxidized. Oxidation results from the removal of electrons, often as part of hydrogen atoms; it is the opposite of reduction. The two electrons this reaction releases pass to a series of electron carriers. The regenerated NAD+ can once again accept electrons, and is recycled.
Chapter 4 (pp. 118—119). As electrons are passed from one carrier to another, the carriers are alternately reduced and oxidized as they accept or release electrons. The transported electrons gradually lose energy as they proceed down the chain.
Physiology, Ninth Edition Respiration/Nucleic Acids on which the energy reactions take place. In a muscle cell, the inner mitochondrial membrane, if stretched out, may be as much as forty-five times as long as the cell membrane!
Thus, oxygen is the final electron acceptor. In the absence of oxygen, electrons cannot pass through the electron transport chain, NAD+ cannot be regenerated, and aerobic respiration halts.
Note in figure 4.12 that as electrons pass through the electron transport chain, energy is released. Some of this energy is used by a mechanism involving the enzyme complex ATP synthase to combine phosphate and ADP by a high-energy bond (phosphorylation), forming ATP. Also note in fig ures D.1 and D.2 that twelve pairs of hydrogen atoms are released during the complete breakdown of one

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Retrieved Text: Aerobic cellular respiration is a part of cellular respiration, and it plays an important role in producing the energy that is required for various functions of a cell.
All organisms are made up of tiny cells which carry out various functions. Energy is required for processing these functions. This energy is provided by the cells, and is produced when the cells break down the chemical composition of food molecules and convert them into energy, i.e. convert glucose to energy. This is made possible with the process called cellular respiration, which takes place in the mitochondrion - the power house of a cell. During this process, cells break down glucose molecules and release energy. This energy that is released from the glucose is used to produce ATP. Therefore, cellular respiration is the process by which energy from glucose is transferred to ATP. It is a part of metabolism and all organisms go through cellular respiration.
Cellular respiration is of two types - anaerobic respiration and aerobic respiration. Here, we shall discuss aerobic respiration.
Cellular respiration is vital for the survival of all organisms, as energy from food (glucose) cannot be used by a cell until it is converted to ATP. Hence, it is a continuous cycle that takes place in all organisms. Aerobic respiration plays a crucial role in the production of ATP, where glucose and oxygen are vital elements. This process takes place only if oxygen is available. Take a look at the chemical formula given here.
Aerobic respiration takes place in three phases - Glycolysis, Krebs Cycle, and Oxidative

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Retrieved Text: Oxidative phosphorylation is a metabolic process in which energy is harnessed for the production of ATP. The process occurs in the mitochondria. Electrons released through the oxidation of glucose are shuttled into the oxidative phosphorylation supercomplex via FMNH2. The electrons are passed through a remarkable electron transport chain along and across the mitochondrial membrane. The electron transport chain releases minute amounts of energy with each electron transfer, and the transport is coupled to the pumping of protons across the mitochondrial membrane. Eventually, the electrons are delivered to molecular oxygen, which is reduced to water. Finally, the protons that have gathered on the edge of the mitochondrial membrane cascade back across, turning a molecular millwheel that drives the manufacture of ATP. The ATP is used to power processes throughout the cell.
The mitochondria are the site of metabolic activity in the eukaryotic cell. The citric acid cycle occurs within the mitochondrial matrix, catalysed by a range of metabolic enzymes. For this reason, mitochondria are sometimes called "the power plants of the cell". Oxidative phosphorylation plays a central role in this production, harvesting electrons from NADH and succinate to manufacture ATP.
The complexes involved in oxidative phosphorylation are embedded in the inner mitochondrial membrane. In the picture below, the lower portion of the outer mitochondrial membrane is visible at the top. The inner mitochondiral membrane stretches across the middle of the picture. Both membranes are formed by lipid bilayers. In contrast, both the intermembrane space and the mitochondrial matrix are aqueous environments. The complexes that take part in oxidative phosphorylation

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Retrieved Text: The citric acid cycle, discovered in 1937 in animal tissue, is the central metabolic pathway for all aerobic processes. The cycle provides the complete oxidation of C2 units (acetyl-CoA) derived from fats, carbohydrates and lipids into carbon dioxide and water capturing the released energy as reductive power in the form of NADH and FADH2. The cycle also provides metabolic intermediates for biosynthetic purposes.
The enzymes and intermediates of the citric acid cycle are found inside the mitochondrial matrix, where the reductive power of NADH and FADH2 can directly be fed (in form of electrons) into the electron transport chain of the oxidative phosphorylation process in the inner membrane of this organelle. This electron flow is coupled to proton flow which is temporarily stored as an electrochemical gradient (proton motif force or PMF) which in turn is harvested by the ATP synthase to produce chemical energy.
The substrate of the cycle is an activated C2 unit - acetate in the form of Acetyl-Coenzyme A. It is derived from glycolysis by a decarboxylating dehydrogenase activity of pyruvate dehydrogenase. This mitochondrial enzyme is organized in three major protein complexes forming a particle larger than a ribosome.
The cycle yields the following intermediates, some of which can be used as biosynthetic precursors.
The oxidation steps include lipoamide dehydrogenase (EC 1.8.1.4). This enzyme is a component (subunit) of both multienzymes pyruvate dehydrogenase complex (E.Cs. 1.2.4.1 + 1.8.1.4 + 2.3.1.12) and (E.Cs. 1.2.4.2 + 1.8.1.4). In fact, the usage of enzyme complex subunits in different enzymes with different substrate specificity but identical reaction mechanism (i.e., use

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Retrieved Text: Where does the energy come from that power the recharging of the ATP molecule?
Cellular Respiration is a chemical process that occurs in all living cells, when trapped energy in the bonds of food molecules are converted to the stored energy in ATP molecules.
Cellular Respiration is a series of chemical reactions that frees the energy in food molecules, making it available to cells.
The chemical process of Cellular Respiration starts when a food molecule (i.e. glucose) enters the cell and is acted upon by the enzymes in the cytoplasm of the cell.
The steps of Cellular Respiration are controlled by ENZYMES.
This process takes place in the MITOCHONDRIA, in the presence of oxygen and is called AEROBIC RESPIRATION (oxygen requiring).
Respiration is generally defined as OXYGEN-REQUIRING; but respiration can also occur WITHOUT OXYGEN (ANAEROBIC RESPIRATION).
– Glycolysis is the 1st series of chemical reactions in cellular respiration, in which glucose is converted to pyruvic acid.
– The entire process can take place whether or not oxygen is present. So Glycolysis is sometimes referred to as ANAEROBIC RESPIRATION.
– It is a series of reactions that take place in the CYTOPLASM of the cell.
– Each chemical reaction is catalyzed (to cause an action to begin) by an enzyme.
– The chemical reactions of glycolysis are anaerobic, because they occur without oxygen.
– All organisms can carry on glycolysis.
– Once GLUCOSE is present in the cell, its chemical bonds are broken down by glycolysis, with the help of enzymes, releasing free energy to make ATP.
– Glucose is not the only cellular fuel. ALL SIMPLE SUGARS in the diet

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Retrieved Text: Is water polar or non polar?
Chemical energy is what type of energy and where is it stored?
What type of bonds are in water? Why is it like this?
Which types of molecules are hydrophilic?
Which types of molecules are hydrophobic?
Why can water absorb such a large capacity of heat?
What is the basis of the pH scale and what does the scale express?
When does chemical equilibrium occur?
In cells most proteins are ___ that function as _____.
What makes amino acids are reactive and stable in water?
What side chains make an amino acid more chemically reactive?
Does polymerization require energy? Is it spontaneous?
What type of reaction of monomers polymerize through?
Amino acids are connected by ___ which form in ____ reactions.
What forms a proteins secondary structure?
In nucleic acid polymerization, how many phosphates are transferred and what does the process create?
What raises potential energy in molecules?
Which base pairs have 2 hydrogen bonds and which have 3?
Why does DNA make a poor catalyst?
Why is RNA more reactive?
In a monosaccharide, what is the difference between aldose and ketose?
Plants store sugar as ___ and animals store it as ____.
How do carbohydrates provide structure?
Why do biologists not thing that polysaccharides played no part in the origin of life?
Why do carbohydrates have more free energy than CO2?
What enzyme do most animal cells contain so that they are able to readily break down glycogen to provide glucose?
What are plasma membranes made up of?
What kind of permeability do phospholipid bilayers have?
What kind of molecules can pass through a phospholipid bilayer?
Factors that influence the behavior of the membrane?
Difference between unsaturated and saturated

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Retrieved Text: This is to be transported into mitochondria by a Pyruvate transporter. It is a simport, where the hydrogen ion is a transporter. Here two different enzymes are involved based on the condition. They are Pyruvate dehydrogenase and Lactate dehydrogenase enzymes. There are 2 different conditions are monitored by the Pyruvate fate.
Glycolysis occurs in both aerobic respiration and anaerobic respiration. During this stage, each glucose molecule splits in half, forming two molecules of pyruvate. If oxygen is present, the pyruvate breaks down further into carbon dioxide, hydrogen ions and an electron transport molecule called NADH (the reduced form of nicotinamide-adenine dinucleotide).
the fate of pyruvate after glycolysis depends on if you have ____ or not. oxygen. in order for pyruvate to go into the krebs cycle it must have ____ hub. ... which krebs cycle intermediate helps to regulate the overall rate of glycolysis by direct influence on the activity of phospfructokinase.
The Fate of Pyruvate (30 pts): During anaerobic exercise or fermentation, the pyruvate produced by glycolysis is further processed to give lactate (in muscle) or ethanol and carbon dioxide (in yeast), as shown below. When we ingest ethanol, it is metabolized by liver alcohol dehydrogenase. Pyruvate is given at the right.
Although glycolysis doesn’t require oxygen, the fate of the pyruvate molecules depends on whether oxygen is present. If oxygen isn’t available, the pyruvate is converted to lactate, and no additional ATP is produced from this conversion. If oxygen is present, the pyruvates are transported into the mitochondrial matrix.
After glycolysis and citric acid cycle, what is the fate

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Retrieved Text: Oxidation pyruvate and citric acid cycle diagram The krebs cycle is named after its discoverer hans krebs. It is also known as the citric carbon pyruvic acid molecules are converted to a two carbon molecule attached to coenzyme a called acetyl The carbohydrates fats and proteins from the diet can propel metabolism by contributing to the citric acid cycle. Carbohydrates are broken down to glucose and through the glycolytic pathway the A detailed schematic diagram in the krebs cycle. 2. The tca cycle the second part of aerobic respiration is the tca cycle also known as the krebs tricarboxylic acid cycle or the citric acid.
Oxidation pyruvate and citric acid cycle diagram More than 60 years ago otto warburg recognized that cancer cells differ from normal cells in the metabolic pathway they use for the oxidation of sugar. Rather than the typical series of oxidative More than 60 years ago otto warburg said that cancer cells differ from normal cells in the metabolic pathway they use for the oxidation by the citric acid cycle and reduced tumor growth. The Promoted a shift to sugar metabolism by the citric acid cycle and reduced tumour growth. The researchers also identified the enzyme pyruvate dehydrogenase kinase 1 as one of the targets for wnt.
Oxidation pyruvate and citric acid cycle diagram Most of glucose 6 phosphate enters the glycolytic pathway to generate pyruvate and atp. Pyruvate is converted to acetyl coenzyme a coa which enters the citric acid cycle in the mitochondria and More than 60 years ago otto warburg recognized

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Retrieved Text: 2) synthesis by transfer of high-energy phosphoryl groups to adp. neither occurs without the other. heat production – brown adipose tissue process of atp synthesis in mitochondria calcium ion storage apoptosis – program cell death primary research paper ideas for high school 10 the electron transport chain how to write medical case series definition is the final ethyl nonanoate synthesis of benzocaine and most important step of cellular respiration.while glycolysis and the citric acid cycle make the necessary precursors, the electron transport chain is where a majority of the atp sensations bar pattaya review journal newspaper is created the electron transport chain makes energy. that’s not very how to check my case status online ceac geoecology essayshark much this process takes place process of atp synthesis in mitochondria bronx ny criminal case search in the folds of the mitochondria where a substance known process of atp synthesis in mitochondria as adenosine triphosphate or atp is created. atp synthesis newspaper articles on gender issues in the world in both chloroplast and mitochondria involves a process called_____. 3. happy studying! however, mitochondria is very dynamic in that it can reverse its process roughly 25% of mitochondrial proteins participate in maintenance or expression of the organellar genome at the inner surface of the inner membrane, providing 7 membrane proteins whose synthesis nucleates the assembly of three respiratory complexes the process is then recycled back to atp with the help of atp synthase as the adp molecule passes through the mitochondria. atp is the chemical energy “currency” of the cell

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Retrieved Text: Outline that cell respiration involves the oxidation and reduction of electron carriers.
State that phosphorylation of molecules makes them less stable.
Outline that in glycolysis, glucose is converted to pyruvate in the cytoplasm.
Explain how glycolysis gives a small net gain of ATP without the use of oxygen.
Explain how, in aerobic cell respiration, pyruvate is decarboxylated and oxidised to form acetyl coenzyme A in the link reaction.
Analyse diagrams of the pathways of aerobic respiration to deduce where decarboxylation and oxidation reactions occur.
Explain how, in the Krebs cycle, the oxidation of acetyl groups is coupled to the reduction of hydrogen carriers, liberating carbon dioxide.
State that energy released by oxidation reactions is carried to the cristae of the mitochondria by reduced NAD and FAD.
Explain how the transfer of electrons between carriers in the electron transport chain in the membrane of the cristae is coupled to proton pumping.
Explain how, in chemiosmosis, protons diffuse through ATP synthase to generate ATP.
Outline that oxygen is needed to bind with free protons to form water to maintain the hydrogen gradient.
Explain how the structure of the mitochondrion is adapted to the function it performs.
Outline that electron tomography can be used to produce images of active mitochondria.
Annotate a diagram of a mitochondrion to indicate the adaptations to its function.
Objectives: Three introductory ideas for respiration. The steps of respiration (what you need to understand). Adaptations of mitochondria.
FAD (Flavine adenine dinucleotide): an electron carrier too, becomes FADH2.
NAD and FAD are similar, but you only find FAD in the krebs cycle while NAD is found in many stages.
Electron transport chain and

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Retrieved Text: D. None of the choices are correct.
ASM Objective: 03.02 The interactions of microorganisms among themselves and with their environment are determined by their metabolic abilities (e.g., quorum sensing, oxygen consumption, nitrogen transformations).
ASM Objective: 03.03 The survival and growth of any microorganism in a given environment depends on its metabolic characteristics.
2. Although most metabolic reactions are freely reversible, a few irreversible catabolic steps are bypassed during biosynthesis with special enzymes that catalyze the reverse reaction in order to allow for independent regulation of catabolic and anabolic pathways.
3. Metabolic pathways can be either catabolic or anabolic but not both.
4. __________ pathways are those that function both catabolically and anabolically.
5. The catabolism of glucose begins with one or more of the glycolytic pathways that yield pyruvate.
6. ____________ ____________ is a process that can completely catabolize an organic energy source to CO2 using the glycolytic pathways and TCA cycle with O2 as the terminal electron acceptor for an electron transport chain.
7. Very few Gram-positive bacteria utilize the Entner-Doudoroff glycolytic pathway.
8. Some aerobic bacteria lack the Entner-Doudoroff and Embden-Meyerhoff pathways and instead use the pentose phosphate pathway for glycolysis.
9. An organism may use glycolysis and the pentose phosphate pathway simultaneously.
D. All of the choices are correct.
13. The synthesis of ATP from ADP and Pi, when coupled with an exergonic chemical reaction is called __________ phosphorylation.
D. two ATP or GTP molecules.
17. After glycolysis, pyruvate is oxidized to one CO2 and the two-carbon molecule acetyl-CoA by a multienzyme system called the ________ ________ complex.
18. TCA cycle enzymes are found in the _____________ _________

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Retrieved Text: What Molecules Enter the Krebs Cycle & What Molecules Leave the Krebs Cycle?
What Happens When There Is No Oxygen Available at the End of Slow Glycolysis?
What Follows Glycolysis if Oxygen Is Present?
What Is Produced As a Result of Photosynthesis?
Living things, all of which consist of one or more individual cells, can be divided into prokaryotes and eukaryotes. Virtually all cells rely on glucose for their metabolic needs, and the first step in the breakdown of this molecule is the series of reactions called glycolysis (literally, "glucose splitting"). In glycolysis, a single glucose molecule undergoes a series of reactions to yield a pair of pyruvate molecules and a modest amount of energy in the form of adenosine triphosphate (ATP).
The ultimate handling of these products, however, varies from cell type to cell type. Prokaryotic organisms do not participate in aerobic respiration. This means that prokaryotes cannot make use of molecular oxygen (O2). Instead, the pyruvate undergoes fermentation (anaerobic respiration).
Some sources include glycolysis in the process of "cellular respiration" in eukaryotes, because it directly precedes aerobic respiration (i.e., the Krebs cycle and oxidative phosphorylation in the electron transport chain). More strictly, glycolysis itself is not an aerobic process simply because it does not rely on oxygen and occurs whether or not O2 is present. However, since glycolysis is a prerequisite of aerobic respiration in that it supplies pyruvate for the reactions thereof, it is natural to learn about both concepts at once.
Glucose is a six-carbon sugar that serves as the most important single carbohydrate in human biochemistry. Carbohydrates contain

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Retrieved Text: Supplementation of L-carnitine improves mitochondrial enzymes in heart and skeletal muscle of aged rats.
Department of Medical Biochemistry, Dr AL Mudaliar Post Graduate Institute of Basic Medical Sciences, University of Madras, Taramani Campus, Chennai, India.
Aging is characterized by a general decline in physiological functions that affects many tissues and increases the risk of death. Deterioration of mitochondria, the major source and target of reactive oxygen species (ROS), is implicated in aging and a variety of age-related diseases. In the present study, the activities of citric acid cycle enzymes, such as isocitrate dehydrogenase, alpha-ketoglutarate dehydrogenase, succinate dehydrogenase, and malate dehydrogenase, were found to be decreased in aged rats as well as that of electron-transferring enzymes such as NADH dehydrogenase and cytochrome c oxidase. After supplementation of carnitine to aged rats, the activities of these enzymes reverted nearer to that of young control rats. These findings suggest that L-carnitine improves the activities of mitochondrial enzymes, increases the electron flow through the electron transport chain, and improves reducing equivalence, thereby improves energy status in aged rats.

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Retrieved Text: Current time: And so, of course, maybe the question we should really be asking is how many protons does it take, or how many protons need to flow through this ATP synthase to phosphorylate one molecule of ADP into ATP, and so, I'm actually gonna go ahead back to our ratios up here and write up here that if we knew how many protons were necessary to produce one molecule of ATP, we would be able to calculate essentially the ratio of ATP to NADH or FADH two.
So, of course, to get back to this kind of elusive calculation of ATP, researchers have done controlled studies in which they basically take a known amount of NADH or FADH two and they have mitochondria available in the lab, and they basically allow the mitochondria to oxidatively phosphorylate these molecules and essentially measure how much ATP is produced, but kind of to their surprise at first, they found that for NADH, for one molecule of NADH, they calculated, there was not a whole number of ATP produced, in fact, they found that there was somewhere between two to three ATP molecules produced for every one NADH molecule.
And this oxidative refers to the fact that this process requires oxygen and in fact, the importance of oxygen here is that this oxygen is reduced by electron carrier molecules and something called the electron transport chain so, remember that we have a electron carrier molecules called NADH and FADH two that are produced at various stages of cellular respiration, glycolysis, the

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Retrieved Text: Exam 2 will cover chapters 4, 5, and 6.
What is the cell theory? What is a cell membrane made out of? What kind of biological molecule is this? What is the basic difference between Prokaryotes and Eukaryotes? What are the following cellular components: Nucleus, DNA, chromatin, nucleolus, ribosome, endoplasmic reticulum, Golgi apparatus, mitochondrion, lysosome, chloroplast.
What is diffusion? Passive diffusion? Facilitated diffusion? What is active transport? Exocytosis? Endocytosis/phagocytosis? What is osmosis?
What is an enzyme? What is activation energy? What is a substrate and an active site? What does 'induced fit' mean? Are enzymes reused? How specific are enzymes? That is, can they be used on many different substrates?
What is oxidation? What is reduction? Which has more "energy", something that is oxidized or something that is reduced? In redox reactions, what, exactly, is moving from whatever is being oxidized to whatever is being reduced? What is the cellular energy molecule called? What is cellular respiration? Does cellular respiration generally require oxygen (is it usually aerobic?) Know the equation for cell respiration, glycolysis, citric acid cycle (+ acetalCoA step), electron transport. Know where each occur. Know what powers ATP Synthase directly; know exactly what the ETC does and how (produces H+ gradient). Know the flow electrons in cell respiration; where they come from, what moves them around, and the final electron acceptor. Know the importance of oxygen, and what happens when there is no oxygen. Know the function of fermentation and where it occurs.

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Retrieved Text: All parts of the body (muscles, brain, heart, and liver) need energy to work. This energy comes from the food we eat. It happens due to some sequential biochemical phenomenon known as metabolism.
The endocrine system stimulates reactions of metabolism by releasing hormones like cortisol, glucagon and adrenaline; digestive system provides nutrients; nutrients through blood; respiratory system provides oxygen and excretory system eliminates waste. So metabolism which is the most important function in maintaining life can happen only with perfect coordination of all other systems in the body.
Metabolism refers to all chemical reactions occurring in living organisms, including digestion and the transport of substances into and between different cells to sustain life. These processes allow the living organisms to grow and reproduce, maintain their structures, and respond to their environments.
Metabolism is the set of chemical reactions that happen in the cells of living organisms to sustain life. These processes allow organisms to grow and reproduce, maintain their structures, and respond to their environments. The word metabolism can also refer to all chemical reactions that occur in living organisms, including digestion and the transport of substances into and between different cells.
Metabolism is usually divided into two categories - catabolism and anabolism. Catabolism breaks down organic matter, for example to harvest energy in cellular respiration. Anabolism uses energy to construct components of cells such as proteins and nucleic acids. The chemical reactions of metabolism are organized into metabolic pathways, in which one chemical is transformed through a series of steps into another chemical, by a sequence of enzymes. Enzymes

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Retrieved Text: Previous ed.: Stamford, Conn.: Appleton & Lange, 2006.
Biochemistry & medicine -- Water & pH -- Amino acids & peptides -- Proteins: determination of primary structure -- Proteins: higher orders of structure -- Proteins: myoglobin & hemoglobin -- Enzymes: mechanism of action -- Enzymes: kinetics -- Enzymes: regulation of activities -- Bioinformatics & computational biology -- Bioenergetics: the role of ATP -- Biologic oxidation -- The respiratory chain & oxidative phosphorylation -- Carbohydrates of physiologic significance -- Lipids of physiologic significance -- Overview of metabolisms & the provision of metabolic fuels -- The citric acid cycle: the catabolism of acetyl-CoA -- Glycolysis & the oxidation of pyruvate -- Metabolism of glycogen -- Gluconeogenesis & the control of blood glucose -- The pentose phosphate pathway & other pathways of hexose metabolism -- Oxidation of fatty acids: ketogenesis -- Biosynthesis of fatty acids & eicosanoids -- Metabolism of acylglycerols & sphingolipids -- Lipid transport & storage -- Cholesterol synthesis, transport, & excretion -- Biosynthesis of the nutritionally nonessential amino acids -- Catabolism of proteins & of amino acid nitrogen -- Catabolism of the carbon skeletons of amino acids -- Conversation of amino acids to specialized products -- Porphyrins & bile pigments -- Nucleotides -- Metabolism of purine & pyrimidine nucleotides -- Nucleic acid structure & function -- DNA organization, replication, & repair -- RNA synthesis, processing, & modification -- Protein synthesis & the genetic code -- Regulation of gene expression -- Molecular genetics, recombinant DNA, & genomic technology -- Membranes: structure & function -- The diversity of the endocrine

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Retrieved Text: These are notes from lecture 8 of Harvard Extension’s biochemistry class.
The citric acid cycle or Kreb’s cycle is the cell’s metabolic hub, as it not only generate energy from pyruvate (the product of glycolysis) but along the way also can consume and produce metabolites relevant to host of other processes. It’s called a “cycle” and not a “pathway” because it both begins and ends with oxaloacetate. It takes place inside the mitochondrial matrix.
Pyruvate from glycolysis does not enter directly into the citric acid cycle. First it passes through a “transition phase” where it is undergoes oxidative decarboxylation to CO2 at the hands of the pyruvate dehydrogenase complex, transferring acetyl groups to coenzyme A to yield acetyl-CoA. This can be considered as step 0 and is depicted at the top of the below diagram. Pyruvate dehydrogenase deficiency causes a neurodevelopmental disorder and can result from mutations in many of the different genes involved in the complex.
Source: this is a Wikimedia Commons featured image by multiple authors.
What’s not depicted in this diagram is there are a few ways to enter the CAC. Pyruvate can come either from glycolysis or amino acid catabolism. Amino acid catabolism or fatty acid catabolism can also yield acetyl-CoA directly.
tl;dr: when ample fuel is available, i.e. the [ATP]/[AMP] ratio and [NADH]/[NAD+] ratios are high, there’s no need to continue running the cycle.
substrate availability. availability of oxaloacetate and acetyl-CoA as inputs.
product inhibition. for instance NADH not only inhibits the pyruvate dehydrogenase complex (above table) but also inhibits other regulatory steps.
competitive feedback inhibition. for instance, succinyl-CoA,

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Retrieved Text: The second step of aerobic respiration goes by many different names. Some text books will call it the citric acid cycle others will name it after the guy who discovered it the Krebs cycle or I've even seen it refereed to as the TCA cycle which stands for tricarboxylic acid cycle. No matter what name you go by, it's all the same thing it's the final breakdown of glucose after the glucose was initially split in half like glycolosis. Now it happens in the matrix part of the mitochondria and the ultimate yield of the Krebs cycle for every one glucose that enters the cell it gives you a pair of ATPs, 8NADHs, and a couple of FADH2 now I'll discuss what goes on a little bit more in just a moment.
But first I want help and make sure that you understand what's going on, now if we take a look at any living organism that's a eukaryote i.e. it has a nuclears it'll have somewhere in the cell mitochondria like this plant cell you can see it has mitochondria and that's a trick question that a lot of teachers like to stick with it. They'll ask you which cells had mitochondria and they want you to say just animal cells but remember plants do aerobic respiration to break down the sugar that they themselves are making for their own purposes. So if we take a look at the structure of the mitochondria you can see it has an outer membrane and then it has this

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Retrieved Text: Adenosine triphosphate, also known as ATP, is a molecule that carries energy within cells. It is the main energy currency of the cell, and it is an end product of the processes of photophosphorylation (adding a phosphate group to a molecule using energy from light), cellular respiration, and fermentation. All living things use ATP.
That is why the amount of ATP produced by cellular respiration is estimated to be between 36 and 38 moles. Also: Biology textbooks often state that 38 ATP molecules can be made per oxidized glucose molecule during cellular respiration (2 from glycolysis, 2 from the Krebs cycle, and about 34 from the electron transport system).
ATP is produced at the levels of cellular respiration. It is produced and consumed in anaerobic as well as aerobic respiration. The production of ATP consists of three major pathways namely glycolysis, Krebs cycle or citric acid cycle and electron transport phosphorylation or beta oxidation.
Cellular Respiration study guide by Miss_Salter2 includes 36 questions covering vocabulary, terms and more. Quizlet flashcards, activities and games help you improve your grades.
A summary of Cellular Energy Sources in 's Cell Respiration: Introduction. Learn exactly what happened in this chapter, scene, or section of Cell Respiration: Introduction and what it means. Perfect for acing essays, tests, and quizzes, as well as for writing lesson plans.

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Retrieved Text: Like starch, cellulose is a glucose polymer found in plants. what accounts fro the chemical difference between them?
What mediate the process of transcription?
How many molecules of ATP result from glycolysis?
what is the main lipid in the plasma (biological) membrane?
The cytoskeleton consists of what?
Where would one encounter a Okazaki fragment?
What roles to NADH and FADH2 have in glycolysis and/or respiration?
What most contributes to "fluid" in nature of biological membrane?
What physical phenomenon accounts for movement of electrons down electron transport chain?
2nd Law of Thermodynamics states that the amount of biologically available energy is always decreasing, how then can we explain the phenomenon of life?
What type of enzyme has more than one binding site?
Lipids, amino acids and nucleic acids are all organic molucules. what is the source of all that carbon?
Proteins are composed of ____ linked together by _____ bonds.
How does calcium aid in the contraction of muscles?
calcium binds to troponin, which results in removal of tropmyosin from binding site.
Cholorphyll of photosystem II is oxidized after absorbing the energy from a photon. What is the source of its replacement electron?
Glycolysis occurs in the ____ the Krebs cycle/electron transport occurs in the ____.
What factor most contributes to maintaining membrane fluidity at low temperature?
What is an example of a couple reaction?
Lactose ____ the lac operon; tryptophan ____ the trp operon.
the synthesis of macromolecules all have what in common?
What is accomplished by phagocytosis?
Light dependent reactions occurs in _____. light independent occurs in ____.
What property of RNA enable it to have enzymatic activity?
What main concept enable biotechnology to be useful?
What can be produced

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Retrieved Text: How can Vinpocetine help Us?
The brain is the control center of all physical and intellectual activity in the body. Ten billion different cells, with millions upon millions of neurons, forming connections several hundred times more numerous than the world's population. At the age of thirty cell units die and are never replaced again, thus beginning an inexorable process that becomes more and more acute in the elderly.
The brain normally receives 15-20% of the body's total blood supply and uses 15-20% of the body's totaled inhaled oxygen. The brain must use this oxygen, along with glucose to produce and use 15-20% of the body's total ATP energy. Unlike most other cells, which can burn fat or sugar (glucose) for their energy needs, neurons can only burn glucose under normal conditions, they typically consume 50% of the total blood glucose. Unlike liver and muscle cells, which can store large amounts of sugar as glycogen, neurons can only store at most a minute or two worth of glucose, and so are dependent upon a continuous and uninterrupted blood supply to maintain normal energy metabolism and avoid injury or death.
Most other cells (except heart and skeletal muscle cells) reproduce continually throughout a lifetime yet after the brain reaches a full complement of neurons (birth to 2 years of age), neurons never reproduce, they are an irreplaceable essential of life.
Under normal conditions of adequate oxygen supply, neurons convert glucose into energy (ATP) through a 3-phase process.
The first phase occurs in the cytoplasm of the cell (the gel-like stuff between the nucleus

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Retrieved Text: A series of free High School Biology Video Lessons.
The Calvin cycle is the second step of photosynthesis which converts ATP into glucose for storage. It is also called the "light independent reaction" or the "dark reaction" because unlike the light dependent reaction, light plays no role in the reaction. The Calvin cycle takes place in the stroma, the semi-liquid fluid inside chloroplasts.
Different steps in the Calvin Cycle.
The citric acid cycle, also known as the Krebs cycle, is involved in cell respiration and produces NADH and FADH2 for the electron transport chain. The Krebs cycle also produces two ATP, but much more ATP is produced later, in the electron transport chain, so that is not its main purpose.
The different steps in the Krebs Cycle.
The light dependent reaction is the first step of photosynthesis which converts light energy into ATP. The light dependent reaction takes place inside the chloroplasts along the thylakoid membrane.
The mechanisms in light dependent reactions.
The electron transport system is the stage in cellular respiration in which oxidative phosphorylation occurs and the bulk of the ATP is produced. The electron transport system creates an electron gradient inside the mitochondria along the inner membrane so that when protons re-enter the matrix through the ATP synthase, their potential energy is converted into chemical energy in the form of ATP.
An overview of the election transport system.

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Retrieved Text: The equation of cellular respiration provides information about the products and reactants of this most important biochemical process. Read to know how this process, the most crucial chemical reaction of life, works in every cell of the body.
Every organism on Earth needs energy for survival. Its life is sustained through the process of respiration at the cellular level, which provides the requisite energy. This process makes every cell an independent unit that creates its own energy. This process of deriving energy is quite complex but it can be adequately summed up with the help of the chemical equation presented further.
Respiration, at the cellular level, is a set of connected metabolic processes that are directed towards converting stored biochemical energy in food, into ATP (Adenosine Triphosphate) molecules, which are the body's energy currency. Through subtle manipulation, with the help of enzymes, energy in the form of ATP molecules is derived from glucose. The production of glucose in turn, is done by plants, through the process of photosynthesis. Glucose and complex carbohydrates, created by plants, are consumed by other animals and processed to derive energy.
Food in the form of carbohydrates and fats is first broken down to simpler form of glucose molecules, which are then processed inside the cell to create ATP molecules.
Every action in the human body is made possible through use of the ATP molecules. That is why, they are called the energy currency of the body. Energy is derived through the conversion of ATP into ADP (Adenosine Diphosphate).
Every metabolic process, including cellular respiration, is complex

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Retrieved Text: Mitochondria (singular: mitochondrion) are organelles within eukaryotic cells that produce adenosine triphosphate (ATP), the main energy molecule used by the cell. For this reason, the mitochondrion is sometimes referred to as “the powerhouse of the cell”. Mitochondria are found in all eukaryotes, which are all living things that are not bacteria or archaea. It is thought that mitochondria arose from once free-living bacteria that were incorporated into cells.
Mitochondria produce ATP through process of cellular respiration—specifically, aerobic respiration, which requires oxygen. The citric acid cycle, or Krebs cycle, takes place in the mitochondria. This cycle involves the oxidation of pyruvate, which comes from glucose, to form the molecule acetyl-CoA. Acetyl-CoA is in turn oxidized and ATP is produced.
The citric acid cycle reduces nicotinamide adenine dinucleotide (NAD+) to NADH. NADH is then used in the process of oxidative phosphorylation, which also takes place in the mitochondria. Electrons from NADH travel through protein complexes that are embedded in the inner membrane of the mitochondria. This set of proteins is called an electron transport chain. Energy from the electron transport chain is then used to transport proteins back across the membrane, which power ATP synthase to form ATP.
The amount of mitochondria in a cell depends on how much energy that cell needs to produce. Muscle cells, for example, have many mitochondria because they need to produce energy to move the body. Red blood cells, which carry oxygen to other cells, have none; they do not need to produce energy. Mitochondria are analogous to a furnace or a powerhouse in the

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Retrieved Text: J Mol Graph Model. 2017 May;73:166-178. doi: 10.1016/j.jmgm.2017.01.003. Epub 2017 Feb 2.
Identifying the molecular functions of electron transport proteins using radial basis function networks and biochemical properties.
Le NQ1, Nguyen TT2, Ou YY3.
Department of Computer Science and Engineering, Yuan Ze University, Chung-Li, Taiwan. Electronic address: khanhlee87@gmail.com.
Department of Computer Science and Engineering, Yuan Ze University, Chung-Li, Taiwan.
Department of Computer Science and Engineering, Yuan Ze University, Chung-Li, Taiwan. Electronic address: yienou@gmail.com.
The electron transport proteins have an important role in storing and transferring electrons in cellular respiration, which is the most proficient process through which cells gather energy from consumed food. According to the molecular functions, the electron transport chain components could be formed with five complexes with several different electron carriers and functions. Therefore, identifying the molecular functions in the electron transport chain is vital for helping biologists understand the electron transport chain process and energy production in cells. This work includes two phases for discriminating electron transport proteins from transport proteins and classifying categories of five complexes in electron transport proteins. In the first phase, the performances from PSSM with AAIndex feature set were successful in identifying electron transport proteins in transport proteins with achieved sensitivity of 73.2%, specificity of 94.1%, and accuracy of 91.3%, with MCC of 0.64 for independent data set. With the second phase, our method can approach a precise model for identifying of five complexes with different molecular functions in electron transport proteins. The PSSM with AAIndex properties in five complexes achieved MCC of 0.51, 0.47, 0.42, 0.74, and 1.00 for independent data set,

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Retrieved Text: YedZ of E. coli has been examined topologically and has 6 TMSs with both the N- and C-termini localized to the cytoplasm (Drew et al. 2002). von Rozycki et al. 2004 identified homologues of YedZ in bacteria and animals. YedZ homologues exhibit conserved histidyl residues in their transmembrane domains that may function in heme binding. Some of the homologues encoded in the genomes of various bacteria have YedZ domains fused to transport, electron transfer and biogenesis proteins (see Figure 8 in von Rozycki et al. 2004). One of the animal homologues is the 6 TMS epithelial plasma membrane antigen of the prostate (STAMP1) that is overexpressed in prostate cancer. Some animal homologues have YedZ domains fused C-terminal to homologues of NADP oxidoreductases.
YedZ homologues arose by intragenic triplication of a 2 TMS-encoding element. They exhibit statistically significant sequence similarity to two families of putative heme export systems and one family of cytochrome-containing electron carriers and have biogenesis (von Rozycki et al. 2004). YedZ homologues can function as heme-binding proteins that facilitate or regulate oxidoreduction, transmembrane electron flow and transport. Homologues of YedZ are found in a variety of bacteria, including magnetotactic bacteria and cyanobacteria where YedZ domains are fused C-terminal to magnetosome transporters of the MFS superfamily (TC #2.A.1) and to electron carriers of the DsbD family (TC #5.A.1), respectively.
YedZ homologues are found in animals where one includes a human 6 TMS epithelial plasma membrane antigen that is expressed at high levels in prostate cancer cells (Hubert et al. 1999; Yang et al. 2001). Even more distant

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Retrieved Text: Oxidative phosphorylation is a combination of two simultaneous processes; the electron transport chain and chemiosmotic coupling. The electron transport chain (also known as the respiratory chain) comprises 4 complexes located in the inner mitochondrial membrane.
Oxidative phosphorylation is a combination of two simultaneous processes; the electron transport chain and chemiosmotic coupling. The electron transport chain (also known as the respiratory chain) comprises 4 complexes located in the inner mitochondrial membrane. NADH and FADH2, produced from glycolysis and the Krebs cycle, release electrons at certain points in the chain, which are passed from one electron acceptor to the next. Each time an electron is passed from one complex to the next, it loses energy.
Chemiosmotic coupling harnesses the energy from the electron transport chain and uses it to transport H+ across the inner mitochondrial membrane, establishing a concentration gradient. ATP synthase is found in the inner mitochondrial membrane and this enzyme uses the energy from H+ ion flux to synthesize ATP. Three ATP molecules can be made from each pair of electrons from NADH and two ATP molecules are made from a pair of electrons from FADH2.
Tocris offers the following scientific literature for Oxidative Phosphorylation to showcase our products. We invite you to request* or download your copy today!

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Input Text: Answer the following question given this paragraph: 

Alternative energy sources include wind power, solar power, hydropower, and geothermal power.


Q: Wind power, solar power, hydropower, and geothermal power are called renewable sources of energy or what other term?

 Choices:

- mandatory energy

- alternative energy

- conservative energy

- specific energy

A:

Target Text: alternative energy

#### Retrieved Documents ####

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Retrieved Text: Mr DT: Learn about renewable energy sources; including; solar, biomass, hydropower, wind, etc.
Renewable energy sources are those energy sources which are not destroyed when their energy is harnessed. Fossil fuels are not renewable energy sources because they cannot be easily replaced. Renewable energy requires technologies that harness natural phenomena, such as sunlight, wind, waves, water flow and geothermal heat.
Solar power is energy from the sun this comes in the form of sunlight. Solar energy (energy from the sun) can be captured by solar panels. There are two types of solar panels these use different technology to harness the energy from the sun.
• The first is Solar Water Heating collectors: These panels absorb energy from sunlight and transfer it to heat up water for showers, radiators, etc.
• The second is Photovoltaic or solar electric panels: These panels transform the sunlight directly into electricity.
Solar panels should be roof mounted and not obscured so they can collect the most amount of energy from the sun. Solar power cells are still relatively expensive to manufacture.
Biomass is a collective term for all plant and animal material. A number of different forms of biomass can be burned or digested to produce energy. Examples include wood, straw, poultry litter. Some tips burn waste plant material and use it to generate electricity. Biomass is a very versatile material and can be used to produce heat (for space and water heating), electricity and a combination of heat and power (electricity). The UK has some of the largest examples of the use of Biomass to generate

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Retrieved Text: Take control of your energy costs and consider renewable energy options by selecting an electric supplier that's right for you.
An overview of Class I renewable energy sources including: solar power, wind power, geothermal systems, anaerobic digestion, ocean thermal power, wave or tidal power, hydropower, and biomass.
Connecticut programs that can assist those in need of help with energy bills.
Consumers can access the latest heating oil and propane price surveys and the Connecticut Energy Price Report, which tracks changes in energy prices over the past year for crude oil and heating oil, gasoline, propane, natural gas, and electricity.
Renewable energy sources are continuously replenished on Earth. Sources of renewable energy include wind, solar, geothermal, hydropower and forms of biomass. Incentives and innovative low-cost financing are available to encourage homeowners, companies, municipalities, and other institutions to use renewable energy.
A renewable portfolio standard (RPS) is a state policy that requires electricity providers to obtain a minimum percentage of their power from renewable energy resources by a certain date.

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Retrieved Text: (1) Energy from solar radiation, such as solar energy, water energy, wind energy, and bioenergy.
(2) Energy from the interior of the Earth, such as nuclear energy and geothermal energy.
(3), celestial gravitational energy, such as: tidal energy.
(1) Conventional energy sources such as water energy and nuclear energy.
(2) New energy sources such as bioenergy, geothermal energy, ocean energy, solar energy, and wind energy.
(1) Renewable energy sources such as solar energy, geothermal energy, hydro energy, wind energy, bioenergy, and ocean energy.
(2) Non-renewable energy sources such as nuclear energy.
(1) Primary energy, directly from the energy of nature. Such as: water energy, wind energy, nuclear energy, ocean energy, bioenergy.
(2) Secondary energy sources such as biogas, steam, thermal power, hydropower, nuclear power, solar power, tidal power, wave power generation, etc.

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Retrieved Text: Renewable energy sources (biomass, geothermal, hydropower, solar and wind) accounted for 19.2% of net domestic electrical generation during the first quarter of 2018, according to a new SUN DAY Campaign analysis of data recently released by the U.S. Energy Information Administration (EIA).
Notably, the latest issue of EIA’s “Electric Power Monthly” (with data through March 31, 2018) reveals that wind power accounted for 7.8% of total electrical generation during the first three months of this year, exceeding that produced by hydropower (7.6%).
Solar alone (utility-scale and distributed PV) is now providing 1.8% of the nation’s electrical production, according to SUN DAY. As such, it is now surpassing that supplied by either biomass (1.6%) or geothermal (0.4%).
Moreover, the net electrical generation by solar (utility-scale and distributed PV) during the first quarter more than doubled that of utility-scale oil-fired facilities (those using petroleum liquids and petroleum coke), the report says.
EIA’s report also shows that electric power output by non-hydro renewable sources increased by 13.4% compared to the first quarter of 2017. Geothermal was up by 1.0%, biomass by 1.7%, wind by 12.9% and solar (including small-scale distributed PV) by 33.2%.
However, net electrical generation by hydropower dropped by 6.9%; in turn, the combination of hydropower and non-hydro renewables experienced a net increase of 4.4% compared to the same time period in 2017.
The latest issue of EIA’s “Electric Power Monthly” was released on May 24. The full report can be found here.
A review of the detailed budget numbers provided, does not reflect the associated grant or subsidized $ or target goals for

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Retrieved Text: According to the latest “Energy Infrastructure Update” report from the Federal Energy Regulatory Commission’s Office of Energy Projects, solar, biomass, and wind “units” provided 694 MW of new electrical generating capacity last month or 99.3% of all new generation placed in-service (the balance of 5 MW was provided by oil.) Twelve new solar units accounted for 504 MW or 72.1% of all new electrical generating capacity in October 2013 followed by four biomass units (124 MW – 17.7%) and two wind units (66 MW – 9.4%).
For the first ten months of 2013, renewable energy sources (i.e., biomass, geothermal, hydropower, solar, wind) have accounted for nearly a third (32.8%) of all new electrical generating capacity. That is more than that provided thus far this year by coal (1,543 MW – 12.5%), oil (36 MW – 0.3%), and nuclear power (0 MW – 0.0%) combined. Solar alone comprises 20.5% of new generating capacity (2,528 MW) thus far this year – more than doubling its 2012 total (1,257 MW). However, natural gas has dominated 2013 thus far with 6,625 MW of new capacity (53.7%).
For the first ten months of 2013, compared to the same period in 2012, new capacity from all sources has declined by 27.5% (from 17,008 MW to 12,327 MW).
Renewable sources now account for nearly 16% of total installed U.S. operating generating capacity: water – 8.30%, wind – 5.21%, biomass – 1.32%, solar – 0.59%, and geothermal steam – 0.33%. * This is more than nuclear (9.22%) and oil (4.06%) combined.
A second new federal study, the latest

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Retrieved Text: Energy is the vital force powering our society, industry and eventually our day to day life. Broadly, energy sources can be classified as non-renewable and renewable sources. Non-renewable energy sources are those that can not be replenished (made again) in a short period of time. Petroleum (crude oil), coal, natural gas and Uranium are examples of non-renewable energy sources. Renewable energy sources can be replenished in a short period of time. For example, solar energy, wind, geothermal, hydropower and biomass are renewable energy sources.
Lesson on sources of energy. Energy sources are systems which make energy in certain ways, for example a nuclear power station. The lesson explores three main energy sources - nuclear power, fossil fuels, and renewable sources. It explains the pros and cons of these energy sources.
The presentation introduces and explains the processes involved in oil exploration, drilling and refining. Video footage was filmed in the Illinois Basin with scenes from a geologist's office, drilling rig, pumping unit, refinery, and more.
What is crude oil? Why does our world depend so extensively on this natural resource? Learn all about it in this video.
Learn about natural gas, its benefits and how it can be part of a cleaner energy future. Natural gas is a very efficient fuel to generate electricity, to power industry, to warm homes and even to fuel cars.
The lesson explains how fossil fuels, especially coal, are used to generate electricity in thermal power plants.
How do you Make Electricity from Coal?
How is electricity made from coal? This presentation with excellent 3D animation shows how

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Retrieved Text: Renewable Energy and Government Policy in the U.S.
Renewable sources of power production are growing, but they are very far from being able to meet America’s energy needs. The US spends roughly $1 trillion each year, or 10% of gross domestic product, on the fuel needed to power its economy. An Environment America report, called The High Cost of Fossil Fuels, predicts that by 2030, the US could spend as much as $1.7 trillion a year for coal and oil. The report estimates that between 2010 and 2030, the US will spend $23 trillion on coal and oil.
Renewable sources of power are capable of meeting America’s energy needs. Even though enough sunlight hits the Earth in a single hour to fuel the human population for a year, harnessing that power is a major endeavor. According to nonprofit research institute SRI International, to replace the world’s demand for oil with renewable energy, it would take roughly 4.2 billion solar rooftops, 300 million wind turbines, 2,500 nuclear power plants or 200 Three Gorges Dams.
To maximize renewable energy, each geographical region needs to leverage its own strengths. For example, in Texas, wind power predominates, southern California has ideal conditions for solar energy while Hawaii and Alaska have substantial geothermal resources. (In Hawaii, the Puna Geothermal power plant provides roughly 30% of the Big Island’s power).
The Interstate Renewable Energy Council (IREC) is a leading source of information on renewable energy policy. Recently, IREC published DSIRE`s Top 10 in ’10 list of the US states that have the best renewable energy policies.

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Rank: 7
Score: 77.187645
Retrieved Text: Renewable energies include all energy sources that do not come from finite resources. They include wind energy, hydropower, solar energy (solar thermal, photovoltaics), bioenergy (biomass and biogas) and geothermal energy.
All renewable energies are based on three sources: The nuclear fusion of the sun, tidal power due to planetary motion, and the geothermal energy of the Earth's core – whereby solar energy is by far the most abundant form. Each year it supplies energy roughly equivalent to 10,000 times the current global energy demand to the Earth's surface.
Their limitlessness or renewability sets renewable energies apart from fossil fuels, which have formed over millions of years and therefore cannot be regenerated in the short term.
Secondary forms of energy that are derived from renewable resources, such as electricity, heat or biogas, are also often imprecisely referred to as renewable energies in common parlance. In addition to an increasingly efficient use of energy, including building modernization and the use of energy-saving technologies, the use of renewable energy is considered the most important component of a sustainable energy supply. The use of solar, wind, hydro, bioenergy and geothermal energy not only reduces CO2 emissions, but also our dependence on fossil fuels.
Renewable energy sources are becoming increasingly important. The International Energy Agency (IEA) forecasts that by 2030 more than a quarter of all energy consumption worldwide can be covered by renewable energies. Studies by institutions such as the German federal government’s Scientific Advisory Council on Global Change (WBGU) forecast that renewable energy will ensure half of the global energy supply by 2050.
Marquard

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Rank: 8
Score: 77.18562
Retrieved Text: With a sixth of the world’s population, Africa generates a measly four percent of the world’s electricity, three-quarters of which is used by South Africa and northern Africa. According to World Bank statistics, more than 500 million Africans (almost two-thirds of the total population) have no access to “modern energy.” Hydropower accounts for around 45% of electricity generation in sub-Saharan Africa (SSA) while biomass (mostly firewood) constitutes about 56 percent of all energy use in sub-Saharan Africa. Large-scale use of forest biomass is accelerating deforestation, and the World Bank estimates that 45,000 square kilometers of forest were lost between 1990 and 2005 across all low-income countries in Africa.
Africa has huge renewable energy potential with some of the world’s largest concentration of alternative energy resources in the form of solar, wind, hydro and biomass energy. Overall, 17 countries in sub-Saharan Africa are in the top-33 countries worldwide with combined reserves of solar, wind, hydro, and geothermal energy far exceeding annual consumption. Most of the sub-Saharan countries receive solar radiation in the range of 6-8 kWh/m2/day, which counts among the highest amounts of solar radiation in the world. Until now, only a small fraction of Africa’s vast renewable energy potential has been tapped. The renewable energy resources have the potential to cover the energy requirements of the entire continent.
Several African counties, such as South Africa, Egypt, Morocco, Kenya, Senegal, Madagascar, Rwanda and Mali have adopted national targets for renewable energy, and feed-in tariffs for renewable energy electricity have been introduced e.g. in South Africa and Kenya. Countries such

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Rank: 9
Score: 76.909874
Retrieved Text: New Energy market report from GlobalData: "Hydropower (Large and Small Hydro, and Pumped Storage) in India, Market Outlook to 2025 - Capacity, Generation, Levelized Cost of Energy (LCOE), Investment Trends, Regulations and Company Profiles"
Boston, MA -- (SBWIRE) -- 05/28/2013 -- Hydropower (Large and Small Hydro, and Pumped Storage) in India, Market Outlook to 2025 - Capacity, Generation, Levelized Cost of Energy (LCOE), Investment Trends, Regulations and Company Profiles" is the latest report from GlobalData, the industry analysis specialists that offer comprehensive information and understanding of the hydropower market in India. The report provides in depth analysis on global renewable power market and global hydropower market with forecasts up to 2025. The report analyzes the power market scenario in India (includes thermal conventional, nuclear, large hydro and renewables) and provides future outlook with forecasts up to 2025. The research details renewable power market outlook in the country (includes wind, small hydro, biopower and solar PV) and provides forecasts up to 2025. The report highlights installed capacity and power generation trends from 2001 to 2025 in India hydropower market. The research analyzes investment trends and LCOE for small hydropower in India during 2011-2025. The report provides information on the amount of carbon saved and average number of homes powered by hydropower during 2001-2025. A detailed coverage of renewable energy policy framework governing the market with specific policies pertaining to hydropower is provided in the report. The research also provides company snapshots of some of the major market participants.
- Historical period is during 2001-2011 (unless specified) and forecast period

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Rank: 10
Score: 76.244286
Retrieved Text: As India is striving for the renewable energy sources, one of the biggest business houses in India is gaining the market share of renewable energy with various initiatives in the recent past. Tata Power is India’s largest integrated power company with a significant international presence. From Fuel and Logistics to Generation and Transmission to Distribution and Trading-exploring various renewable sources of energy in India and globally, it has a significant presence in wind, solar, hydro and geothermal energy space. They are one of the largest renewable energy players in India and have developed the country’s first 4000 MW Ultra Mega Power Project at Mundra (Gujarat) based on super-critical technology.
Tata Power is one of the biggest wind energy generators in the country. Its 460.6MW of installed capacity is spread across Maharashtra, Gujarat, Tamil Nadu, Karnataka and Rajasthan. It is also one of the leading solar power generators in India with an operational capacity of 54 MW. Besides Palaswadi, the company has solar plants at Mithapur in Gujarat (25MW), Mulshi in Maharashtra (3MW) and some rooftop solar installations.
The Tata group's renewable energy arm is in talks to invest in a wind energy firm, revving up deal activity in a sector that has lured General Electric, Goldman Sachs and the Asian Development Bank, as the company seeks to achieve its goal of adding as much as 300 MW to its portfolio annually. "We are currently speaking to three wind power companies based in Tamil Nadu, Karnataka and Maharashtra...We hope to close a deal soon as we have a target

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Rank: 11
Score: 75.78137
Retrieved Text: It was quite a year for renewable energy. 2015 set the record for new electrical generation placed in service from solar, wind, hydropower, geothermal and biomass according to the latest Energy Infrastructure Update report released by the Federal Energy Regulatory Commission (FERC) Office of Energy Projects. Of the 16,485 megawatts (MW) of new generating capacity in 2015, 63.85 percent, nearly two-thirds, came from renewable sources.
Wind energy was the largest source of new capacity last year, with 69 new “units” of wind providing 7,977MW of new generating capacity, nearly half the annual total. By contract 50 new units of natural gas brought 5,942 MW of new capacity to the grid, about a third less than for wind.
238 new units of solar energy put 2,042 MW capacity online, 305 MW came from biomass, 153 MW from hydropower and 2 geothermal units brought 48 MW of new generating capacity.
The FERC report shows no new capacity in 2015 from nuclear power, 15 MW from oil and just 3 MW from a single unit of coal. New electrical generating capacity from all renewable energy sources in 2015 – 10,525 MW – is over 700 times greater than the contribution from oil and more than 3,500 times more than that from coal.
The share of energy provided by renewable sources is 17.83 percent of the total installed operating generation capacity in the United States. The share of non-hydro renewables is 9.27 percent, exceeding the 8.56 percent share from conventional hydro. At 108.34 GW of total installed electrical capacity, non-hydro renewables has now eclipsed

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Rank: 12
Score: 75.776184
Retrieved Text: Tidal power, also called tidal energy, is a form of hydropower that converts the energy of tides into electricity or other useful forms of power. The ocean, covering 70% of the Earth’s surface, produces a vast amount of mechanical energy in the form of tides and waves. Tidal power has the potential for future electricity generation. Tidal power is a major growth area, with a global potential up to 100GW installed capacity. As non-renewable energy sources such as coal, oil etc., are being tapped out, new and innovative ways of creating energy of our needs being explored. The extraction and use of fossil fuels are causing many environmental problems of the world, such as climate change, the ozone layer destruction and so forth. The combustion of fossil fuels created an excess of carbon dioxide, an acceptable power generation technology must be mechanically sound, environmentally acceptable, and economically profitable in order to become a real alternative for builders of new capacity. So, renewable energy is the only solution in order to meet up the future crisis. Solar, wind, hydal, wave, tidal, geothermal, biomass, fuel cell etc., are the renewable energy sources. Among them tidal energy is an old but efficient method. Tidal power is classified as a renewable energy source, because tides are caused by the orbital mechanics of the solar system and are considered inexhaustible within a human timeframe. Energy from tidal power is also a form of pollution free energy, which has a lot of potential. Tidal power may be an alternative solution to meet

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Rank: 13
Score: 75.32284
Retrieved Text: Supporting clean energy is good for everyone.
A renewable energy credit (REC)—also sometimes referred to as a renewable energy certificate or green tag—is created for each megawatt-hour (1 MWh, or 1000 kilowatt-hours) of renewable electricity generated and delivered to the power grid.
When renewable energy is generated by wind, solar, biomass, geothermal, and certain hydropower sources, two things are created: (1) the actual electricity, and (2) the environmental benefits associated with the fact that the electricity was produced without burning fossil fuels like coal or natural gas. RECs are the way those environmental benefits or “attributes” are tracked and accounted for.
In an ideal world, we would all have small wind farms or solar panels that generate exactly the amount of energy we need to power our lives. But let’s face it, that’s pretty tough to do. By purchasing RECs, you are supporting clean energy and displacing emissions associated with fossil fuel-powered electric generation.

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Rank: 14
Score: 75.26918
Retrieved Text: The global energy requirement for sustaining economic activities, meeting social needs and social development is increasing daily. Environmentally friendly, renewable energy resources are an alternative to the primary non-renewable energy resources, which devastate ecosystems in order to meet increasing demand. Among renewable energy sources such as hydropower, biopower, geothermal power and solar power, wind power offers distinct advantages to Turkey. There is an increasing tendency toward wind globally and the European Union adjusted its legal regulations in this regard. As a potential EU Member state, Turkey is going through a similar process. The number of institutional and legal regulations concerning wind power has increased in recent years; technical infrastructure studies were completed, and some important steps were taken in this regard. This study examines the way in which Turkey has developed support for wind power, presents a SWOT analysis of the wind power sector in Turkey and a projection was made for the concrete success expected to be accomplished in the future.
The article reports that wind power is being used by Asia's biggest economies and the U.S. as renewable power resources.
Focuses on the economic advantages of using wind energy. Overview on the wind energy industry in the Spanish city of Pamplona; Estimated value of the worldwide industry in 1998; Advantages of wind power over electricity and other traditional means of power generation; Renewable energy sources.
Reports on the progress of the Pennsylvania wind energy project. Generation of clean renewable energy; Environmental message of hotel.
The article reports on the analysis made by the National Renewable Energy Laboratory, stating

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Rank: 15
Score: 75.24993
Retrieved Text: Traunstein is the second largest district in Bavaria in Southern Germany. With a population of 170,000, the district is located is a region called Chiemgau between Munich and Salzburg.Traunstein has set a goal of meeting all their electricity demand with renewable resources by 2020. The district is already more than half way there.
Traunstein's total annual power demand is nearly 650 million kilowatt-hours (kWh) (2010). The district understands that to reach the 100% renewable target, a mix of sources will be required. In 2010, 146 million kWh were supplied by hydropower. Biomass has been growing particularly in the district and generates over 140 million kWh of electricity. Solar power has also expanded significantly, from 18 million kWh in 2005 to at least 68 million kWh. Hydropower, geothermal and wind are viewed as having potential for expansion to reach the 2020 100% goal.
Traunstein held a climate and energy conference in which the district laid out a platform of goals and ideas for their renewable energy planning.

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Rank: 16
Score: 75.070404
Retrieved Text: The Institute of Political Economy (IPE) at Utah State University has released a new set of reports titled: Reliability of Renewable Energy. These reports are an examination of the five most common sources of renewable electricity generation: wind, solar, biomass, geothermal, and hydro. The studies assess each source’s economic, physical, and environmental aspects.
Each of the sections has the following available for download: the full and condensed reports published by IPE, along with a summary one-page document, infographic and videos produced by Strata.
Many Americans are looking to limit the use of fossil fuels, which has led policymakers to mandate and subsidize biomass-generated electricity. Biomass is organic matter such as wood, grasses, or crop residues that are burned to produce electricity, much like coal. Despite government assistance, biomass only generated 1.7 percent of U.S. electricity in 2014. In the Reliability of Renewable Energy: Biomass report, the Institute of Political Economy (IPE) at Utah State University examined the economic, physical, and environmental implications of biomass power to determine its overall reliability as an energy source. IPE found that biomass electricity production, in many cases, is expensive, inefficient, and environmentally damaging. As such, the costs of subsidies and mandates for the biomass industry impose higher costs on taxpayers and energy consumers with limited environmental benefits.
Many Americans are looking to limit the use of fossil fuels, which has led policymakers to mandate and subsidize renewable energy sources like geothermal power. Despite government assistance, geothermal power only generated 0.4 percent of U.S. electricity in 2014. In the Reliability of Renewable Energy: Geothermal

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Rank: 17
Score: 74.77583
Retrieved Text: India has signed an agreement with Iceland to tap geothermal energy in the country, Union Minister for New and Renewable Energy Farooq Abdullah has said.
“We are going deep under the earth”s surface to tap geothermal energy. The potential of it has been identified in Ladakh region, Gujarat and Chatisgarh”, Abdullah said, without giving further details about the agreement.
The minister, who was speaking yesterday at the launch of 2MW variable speed turbine at the Wind Turbine Research Station (WTRS) in Kayathar, said geothermal Energy(GE) would be an important source of energy in future.
He said that once the technology was developed and mastered to tap the GE, it could be shared with other countries.
According to Abdullah, India by 2022, would generate 20,000 MW of power using renweable energy. He said Tamil Nadu continued to lead the country in tapping wind energy.
Tamil Nadu could also focus on producing energy from husk as it was the largest producer of paddy. Village power plants that used husks were successful in Bihar, Punjab and Haryana, he said.
The potential of tidal waves in generating power was being studied. “All possible ways of exploring renewable energy offshore and onshore were being studied”, he said.
Tapping renewable energy as much as possible from solar, wind, biomass and hydropower would make the country pollution free, he said.
He said renewable energy sources was the only way to get power for the 40 per cent of the villages, which remained without electricity.
Abdullah said the ministry was doing its best to see that country did not depend on foreign source

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Rank: 18
Score: 74.55435
Retrieved Text: EGPNA, part of the Renewable Energies division of the Enel Group, is a leading owner and operator of renewable energy plants in North America with projects operating and under development in 23 US states and two Canadian provinces. EGPNA operates around 100 plants with a managed capacity exceeding 4.2 GW powered by renewable hydropower, wind, geothermal and solar energy. In 2017, the company was the fastest growing renewable energy company in the US, bringing approximately 1.2 GW of capacity online. The company is currently the largest wind operator in Kansas and Oklahoma.
Enel Green Power, the renewable energies division of the Enel Group, is dedicated to the development and operation of renewables across the world, with a presence in Europe, the Americas, Asia, Africa and Oceania. Enel Green Power is a global leader in the green energy sector with a managed capacity of around 41 GW across a generation mix that includes wind, solar, geothermal, biomass and hydropower, and is at the forefront of integrating innovative technologies into renewable power plants.

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Rank: 19
Score: 73.9662
Retrieved Text: Solar energy: The sun is a constant and reliable source of energy as well as being an environment friendly source. Appliances that run on solar energy last longer and contribute significantly to lowering utility bills. Photovoltaic cells convert solar energy into electrical energy. PV Cells and panels are commercially viable, reliable, easy to transport, install and inexpensive in the long run.
Water: Hydropower from water is clean power as it does not pollute the atmosphere. Hydropower reservoirs not only supply water and electricity, but are also ideal venues for recreational activities like water sports, swimming, and fishing.
Wind: It is a free resource and hence wind power becomes very cost effective. Harnessing wind power through tall turbines does not need much space and the process is absolutely pollution free. Remote areas with no electricity can produce their own power using windmills.
Biomass: Organic waste from households and farms is a rich source of fuel like methane and ethanol, which can be used to produce electricity. It is inexpensive, and does not adversely affect the environment.
Geothermal: Heat pumps are used to run generators to produce power. Geothermal stations are compact, clean energy sources that cause no air pollution, and are a viable option.
As they are all natural sources of energy, they are sustainable sources which can be replenished quickly and have no adverse effects on the environment.
There is a significant reduction in air, water, and noise pollution.
Does not harm the ecosystem as trees do not have to be cut to set up refineries and power plants.
Reduces depletion of fossil fuels.
Environment

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Rank: 20
Score: 73.4891
Retrieved Text: To give you a sense of scale, your electricity company measures energy in kilowatthours (kWh) and this chart is in terawatt-years (TWy). Energy use for the entire planet in 2015 was 18.5 TWy and growing! That's a lot of energy! But the solar energy available is 23,000 TWy per year - plenty to cover our demands and much more. On the other hand, notice the numbers listed for the finite sources are the total available, not per year. A little math shows just how close we are to exhausting those traditional resources.
So is solar energy renewable? Not only yes, but it’s the most renewable resource we have.
Even if we pretend all energy resources are otherwise created equal, it's easy to see why the Sun is such an attractive option. But most people don't know how all of these resource technologies work, let alone what they are. So let's talk about each of these energy resources to give you a better idea of why things are changing and what our future power supply could look like.
In short, there are two basic kinds of energy resources: finite and renewable. The names are pretty self-explanatory. Finite resources are materials found in the earth in limited quantities. Yes, limited. Meaning they will eventually be gone! Certain new technologies may extend our ability to use finite energy resources but they’re still going to run out eventually. These finite resources include petroleum, natural gas, coal and uranium - the traditional energy mainstays. Renewable resources, on the other hand, are continually generated and

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Rank: 21
Score: 72.698
Retrieved Text: It’s electricity supplied from renewable energy sources, such as wind & solar (sun), geothermal, small hydropower, and various forms of biomass.
Green Power is an earth friendly form of energy that is produced by the planet’s renewable natural resources.
What are we doing for Green Power?
Right now, we’re purchasing one-tenth of a megawatt of power through Bonneville Power Administration’s renewable resource program.
If Green Power has been around for 10 years, why are we pushing it?
Because of recent supply problems in California a couple years ago, there’s a big demand to develop alternate new energy sources and renewable resources.
More than 300 utilities in 32 states now offer some form of green power that allows consumers to support electricity production from renewable resources.
New technology costs more to produce energy.
Biomass production involves construction of facilities to convert certain kinds of waste products (from dairy and pig farms for example) into electricity. These are costly.
What’s in it for me in Montana?
We all need to be aware of the global level of depleting resources. The ripple effect of the heavy demand of populated areas of the west & east coasts effects Montana.
Development of alternate power sources is in progress now & Montanans will benefit from the final outcome.
So, What can I do to support Green Power effort?
If you want MVP to commit to supporting more Green Power, we need your commitment for extra dollars. We’ll then buy more Green Power. Contact one of our offices to learn how you can help support Green Power by your contribution.

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Rank: 22
Score: 72.379265
Retrieved Text: - What They Are: Renewable energy technologies help produce energy from resources that are generally not depleted by human use, such as the sun, wind, and water movement. These energy sources can be converted into heat, electricity and mechanical energy in several ways. Among the technologies that utilize these sources are solar energy, wind, geothermal, biomass and hydropower.
Environmental -- renewable technologies are clean sources of energy that have a much lower environmental impact than conventional energy technologies.
Resource conservation -- renewable technologies rely on ever-renewing resources and help to offset consumption of finite energy sources, such as coal, oil and uranium.
Economic -- investments to build and maintain renewable power generation largely go toward spending on materials and workmanship based in the U.S., rather than on costly energy imports. This investment helps create jobs and fuel local economies. In addition, U.S. companies that produce renewable energy technologies sell their goods and services overseas, which helps reduce the U.S. trade deficit.
Energy security -- renewable technologies help diversity America's base of energy supply and reduce our reliance on costly and sometimes unreliable foreign sources of energy. Such domestic energy production makes us a stronger and more secure nation.

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Rank: 23
Score: 71.960075
Retrieved Text: The global stock index RENIXX® (Renewable Energy Industrial Index, ISIN: DE000RENX014) for renewable energy tracks the 30 largest companies of the renewable energy industry worldwide by market capitalization. The RENIXX World comprises stocks e.g. from sectors as wind energy, solar energy industry, hydropower, geothermal energy, bioenergy or fuel cell technology.
The stocks listed in the RENIXX World cover a broad spectrum of activities, products and services. As for example in the wind power sector the range reaches from manufacturers, wind power project developers and suppliers to utility companies that have invested in on- and offshore-wind energy projects and are active as plant operators. Regarding solar companies the RENIXX World contains companies such as manufacturers of PV-Cells and Modules, PV manufacturing equipment, supplier, project developers or renewable energy utilities. Due to the rather slow constantly driven industry character in the bioenergy sector compared to solar energy relatively few companies are represented in the RENIXX World.

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Rank: 24
Score: 71.71611
Retrieved Text: Who is Green Mountain Energy?
Green Mountain Energy is the nation's longest serving renewable energy retailer. We were founded in 1997 with the mission to change the way power is made, and we are still 100% committed to this mission. Every single product offered by our company has an environmental benefit.
Since 1997, our customers have helped avoid more than 45.7 billion pounds of carbon dioxide emissions by choosing renewable energy, which is like taking over 4.9 million cars off the road for a year. Our customers' demand has also helped spur the development of more than 85 new wind and solar facilities across the nation. Now that's making a difference!
Where is Green Mountain Energy based?
Which states does Green Mountain Energy Company serve?
We currently provide clean energy products to residential and commercial customers under the Green Mountain Energy brand in Illinois, Maryland, Massachusetts, New Jersey, New York, Pennsylvania and Texas. Find out if Green Mountain Energy® electricity is available in your area.
We also market clean energy products through a local utility in Oregon.
Does Green Mountain Energy Company own and operate any wind farms or other renewable generation facilities?
Our customers have helped create demand for the construction of more than 80 wind and solar facilities across the nation representing over 175,000 KW of new renewable energy.
What do you mean “clean” electricity?
The leading cause of industrial air pollution in the country is the production of electricity. While the majority of electricity generated in the U.S. is made by burning pollution-causing fossil fuels like coal, oil and natural gas, our Pollution

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Rank: 25
Score: 71.59839
Retrieved Text: THE GERMAN FEDERAL GOVERNMENT WANTS TO ESTABLISH THE AGE OF RENEWABLE ENERGIES BY 2050 AND QUIT USING NUCLEAR ENERGY BY THE END OF 2022, AT THE LATEST.
Even without nuclear energy, the emission of greenhouse gases is to be reduced 40 percent by 2020 and at least 80 percent by 2050 (compared to 1990). The share of solar energy, wind, and other regenerative energy sources in the power consumption is to be stepped up to at least 35 percent. Currently, this share is about 17 percent.
Power from wind plays an important role, especially offshore wind energy from the North Sea and Baltic Sea. Other sources include hydropower, photovoltaics, geothermal energy, and biomass.
Renewable energies must be combined with modern conventional power plants and power storage units to form a stable supply system. The grid feed-in, which can fluctuate substantially, must be duly controlled. To ensure reliable supply, it must be possible to buffer energy. This is where new, modern energy storage systems come in.
As the power grids are currently not designed for the transport of renewable energies, the grid development must be accelerated. Moreover, intelligent grids and storage units must be implemented, and intelligent power meters must be used.
By 2050, the goal is to cut the need for primary energy by 50 percent. This necessitates massive energy savings and increased energy efficiency. This is partly possible by employing high-end drive, closed-loop, and open-loop technologies.
Still, the affordability, cost efficiency, and effectiveness of all measures must be guaranteed. Energy suppliers need to compensate the wind-up costs resulting from the exit

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Rank: 26
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Retrieved Text: The world’s need for energy is an ever growing appetite and doesn’t show any signs of diminishing. If we are going to keep our planet and ourselves safe and healthy, we need to use energy wisely. What is renewable and non renewable energy and where does it come from?
One of the most enigmatic things in the world is energy. But what is associated with energy? Basically, and in one way or another, everything that we can see, touch and sometimes even think is associated with energy.
How many forms of energy exist? There are a few such as thermal, radiant, chemical, electrical and mechanical. It is difficult to put into words what energy is. It is easier to describe its manifestations. Do you want to boil some water? You need energy. Do you want to drink a glass of water? You need energy. Even thinking can't be performed without energy.
Narrowing our focus, let's look at a specific issue associated with power resources that we depend on. The matter is that the amount of energy expended cannot be more than the amount of energy there was to begin with. Basically, energy can change its forms, but the total amount of energy remains.
Energy can be divided into two types: renewable energy and nonrenewable energy. Renewable energy includes biomass energy, solar energy, wind energy, geothermal energy, hydro energy, and tidal energy. Nonrenewable energy includes oil, natural gas, coal and nuclear energy.
The problem is that most energy we use is taken from nonrenewable energy sources. Oil and natural gas come from

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Retrieved Text: WASHINGTON, D.C. — According to the latest “Energy Infrastructure Update” report from the Federal Energy Regulatory Commission’s Office of Energy Projects, renewable energy sources (i.e., biomass, geothermal, hydropower, solar, wind) accounted for 37.16 percent of all new domestic electrical generating capacity installed during calendar-year 2013 for a total of 5,279 MW.
That is more than three-times that provided for the year by coal (1,543 MW – 10.86 percent), oil (38 MW – 0.27 percent), and nuclear power (0 MW – 0.00 percent) combined. However, natural gas dominated 2013 with 7,270 MW of new capacity (51.17 percent). Waste heat provided the balance of new generating capacity – 76 MW (0.53 percent).
Among renewable energy sources, solar led the way in 2013 with 266 new “units” totaling 2,936 MW followed by wind with 18 units totaling 1,129 MW. Biomass added 97 new units totaling 777 MW while water had 19 new units with an installed capacity of 378 MW and geothermal steam had four new units (59 MW).
The newly installed capacity being provided by the solar units is second only to that of natural gas. The new solar capacity in 2013 is 42.80 percent higher than that for the same period in 2012.
For the two-year period (January 1, 2012 – December 31, 2013), renewable energy sources accounted for 47.38% of all new generation capacity placed in-service (20,809 MW).

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Rank: 28
Score: 71.01168
Retrieved Text: When deciding to live Off The Grid, one of the main concerns (other than a water source) is generating energy to supply your needs.
The first thing we all think of when thinking of green energy is solar.
There are other viable energy sources out there that may suit your needs.
Here are our Top 6 Energy Sources when Living Off The Grid.
The number one source for energy for those living off the grid is solar.
One plus is that most people can install a solar system themselves.
The price reduction in solar systems over the years have made them a viable option.
Solar energy is the cleanest and most abundant renewable energy source available.
The U.S. has some of the richest solar resources in the world.
Modern technology can harness this energy for a variety of uses, including: generating electricity, providing light or a comfortable interior environment, and heating water for domestic, commercial, or industrial use.
If you have 7 hours of daylight per day, solar would be a great option for an energy source.
Wind power is the process by which wind is used to generate electricity.
The two main sources for generating wind energy are windmills and wind turbines.
Wind turbines are classified into two general types: horizontal axis and vertical axis.
Wind turbines, like aircraft propeller blades, turn in the moving air and power an electric generator that supplies an electric current.
Simply stated, a wind turbine is the opposite of a fan. Instead of using electricity to make wind, like a fan, wind turbines use wind to make electricity.
If your property receives an average of

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Rank: 29
Score: 70.771774
Retrieved Text: (MS) - With debates continuing to rage on over the future of the world's environment, more and more research is being done into the viability of renewable energy sources. While some have already begun to embrace such sources, many more are still in the dark as to just what renewable energy sources are.
Renewable energy sources are those that can be replenished in a very small period of time. The most common of these sources include the following.
Biomass: Biomass is organic material made from plants and animals and contains energy from the sun. That energy from the sun is absorbed by plants through photosynthesis, and is then passed on to animals and humans that consume them.
Wood is the most common form of biomass, as wood is used for heating and cooking throughout the world. While it's less commonly used in the United States, wood is an important energy source for much of the developing world. And since it's always possible to plant more trees, wood is among the most renewable energy sources in the world. Other sources of biomass are crops and even biofuels such as ethanol, which continues to be promoted and considered as a means of lessening the world's reliance on petroleum.
Solar energy: Solar energy is energy produced by the sun that can be converted into other forms of energy, such as electricity and heat. Though solar energy is among the less reliable renewable sources of energy, this doesn't mean it isn't valuable. Solar energy is used to heat buildings, dry crops, and heat water.
Geothermal:

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======= Instance Index 8712 =========
Input Text: Answer the following question given this paragraph: 

Carbon Dioxide: Every time you exhale, you release carbon dioxide into the air. It's an odorless, colorless gas. Carbon dioxide contributes to global climate change, but it isn't directly harmful to human health. Carbon Monoxide: Carbon monoxide is produced when matter burns. It's a colorless, odorless gas that is very harmful to human health. In fact, it can kill people in minutes. Because you can't see or smell carbon monoxide, it must be detected with an alarm.


Q: The colorless, odorless gas released when we breath is carbon dioxide. the harmful colorless, odorless gas released when matter is burned is what?

 Choices:

- methane

- acid monoxide

- carbon monoxide

- carbon trioxide

A:

Target Text: carbon monoxide

#### Retrieved Documents ####

Rank: 0
Score: 91.700195
Retrieved Text: Carbon Dioxide is a colorless, odorless, incombustible gas resulting from the oxidation of carbon. Carbon dioxide emissions are directly associated with fossil fuel consumption and industries like construction, breweries and biofuel production.
Because it is odorless and colorless, workers can easily be overcome by high levels of CO2 in confined spaces.
High precision, short response time and excellent structural design.
Internationally advanced infrared sensor technology.
316 L S.S. and Al. Alloy anti-corrosion housing, preventing the erosion of adverse environment like acid, alkali and etc.

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Rank: 1
Score: 88.513794
Retrieved Text: Smog is the general term used to describe a variety of air pollutants, including ground-level ozone (smog's main ingredient), particulate matter, carbon monoxide and nitrogen oxides. It refers to air pollution that is formed when gases from many sources are released into the air and chemically react with each other in sunlight.
Ocean breezes sweep the smog inland toward the mountains where an inversion layer of warm air pushes it down trapping the smog close to the ground where we live and breathe.
Ground-level ozone (O3) is a colorless, odorless pollutant formed by chemical reaction between volatile organic compounds (VOCs) and oxides of nitrogen (NOx) in the presence of sunlight. The primary source of VOCs aid NOx are mobile sources including: cars, trucks, buses, plus agricultural and construction equipment. In contrast, stratospheric ozone in our upper atmosphere, better known as the ozone layer, shields the earth from the suns harmful ultraviolet rays.
Particulate matter (PM) is the term used for a mixture of solid particle, and liquid droplet, found in the air. It originates from a variety of sources, including motor vehicles, power plants, construction activities, soil dust, soot and industrial processes. Course particles (PM10) are generally emitted from sources such as windblown dust, vehicles traveling on unpaved roads, and crushing / grinding operations. Fine particles (PM2.5) can come from fuel combustion (motor vehicles, power generation, industrial facilities) and fugitive dust. PM2.5 is formed primarily in the atmosphere from gases such as sulfur oxides, NOx, and VOCs.
Carbon monoxide (CO) is a colorless, odorless gas by-product of combustion produced primarily

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Rank: 2
Score: 86.35986
Retrieved Text: Gas Poisoning : Hydroxocobalamin Vs.
Carbon monoxide poisoning occurs after enough inhalation of carbon monoxide (CO). Carbon monoxide is a toxic gas, but, being colorless, odorless, tasteless, and non-irritating, it is very difficult for people to detect. Carbon monoxide is a product of incomplete combustion of organic matter with insufficient oxygen supply to enable complete oxidation to carbon dioxide (CO2) and is often produced in domestic or industrial settings by motor vehicles and other gasoline-powered tools, heaters, and cooking equipment. Exposures at 100 ppm or greater can be dangerous to human health.

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Rank: 3
Score: 86.03024
Retrieved Text: Carbon dioxide is a compound containing carbon and oxygen. At atmospheric temperatures and pressures, carbon dioxide is in gaseous form. It is colorless, odorless, about 1.5 times heavier than air and a slightly acid gas. The gas is nonreactive, nontoxic and nonflammable. Solid carbon dioxide (dry ice) is formed at a temperature of -78.5℃.
Used to carbonate soft drinks, PH control in water treatment, in chemical processing, as a food preservative, in chemical and food processing.
Used as a refrigerant when freezing food products, low temperature testing of aviation, missile and electronic components, as well as in fire extinguishers systems.
If you are looking for medical carbon dioxide, Yuantong co2 cylinder will be your best choice, we will provide you with the best quality products and services. Sincerely welcome you to buy our products.

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Rank: 4
Score: 85.64444
Retrieved Text: HOUSTON (Reuters) – Chevron Corp plans to set greenhouse gas emissions targets and tie executive compensation and rank-and-file bonuses to the reductions, the oil major said in its latest climate report released on Thursday.
Chevron’s target aims to reduce emissions and flaring as a percentage of production, but does not set a goal for total emissions – a measure that activist investors prefer. The targets will apply to Chevron’s operations as well as joint ventures or assets it has a stake in but does not operate itself, the company said.
Methane, the main component of natural gas, is colorless and odorless, and has more than 80 times the heat trapping potential of carbon dioxide in the first 20 years after it escapes into the atmosphere, scientists say.

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Rank: 5
Score: 85.3979
Retrieved Text: As for the high carbon dioxide emissions increasing when using fossil fuel,HHO oxyhydrogen generator gradually become popular and acceptable.Alternative energy HHO can meet the energy demands better than any fossil fuels and it has a wide application in the industry of welding,cutting,sealing,energy saving etc.
HHO oxy-hydrogen generator produce oxygen and hydrogen by water electrolysis which we refer to browns gas generator.Theoretically,1 liter water can generate 1860 liters of oxygen and hydrogen with electricity consumption 4kw/h.Oxy-hydrogen gas(HHO gas) is colorless, odorless, no CO, no CO2, no COX and no any other poisonous and harmful material.Besides, hydrogen and oxygen mixed gas would burn into water after using.The alternative energy HHO become a new energy revolution in 21st century.Why?Water as fuel,it is renewable energy.Moreover,it is zero carbon dioxide emissions after burning.HHO generator featured eco-friendly,energy saving,and low cost etc.
Okay Energy,as professional HHO oxyhydrogen generator manufacturer and supplier in China,supply HHO generators and provide HHO energy saving solutions in the world.With the fast development recent years,we have many successful case in the jewelry welding,ampoule bottle sealing,acrylic flame polishing,engine carbon clean,and catalytic converter cleaning.

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Rank: 6
Score: 83.79841
Retrieved Text: ‍Carbon dioxide (CO2) is a nonflammable, colorless, odorless gas. It is found in air at concentration of about 0.03%. Carbon dioxide may exist simultaneously as a solid, liquid, and gas at a temperature of -56.6˚C and a pressure of 60.4 psig. At a temperature of -79˚C and atmospheric pressure, carbon dioxide solidifies forming "dry ice" at density of 97.4 pounds per cubic foot. Because of its low concentration in the atmosphere, air is not a suitable feedstock for carbon dioxide production. Rather, CO2 is obtained from by-product streams from various manufacturing processes. Bulk quantities of carbon dioxide are usually stored and shipped as liquid under elevated pressure and refrigeration.
Blanketing and purging of tanks and reactors. It is also used as shielding gas in the arc welding process. It is the source of the bubbles in soft drinks and other carbonated beverages. It is used to fill certain types of fire extinguishers that rely on its inert properties, densities, and low temperature when released from high-pressure storage.In addition to its "inert" properties, carbon dioxide, as dry ice, is used to freeze a variety of foods.
Carbon dioxide is used in chemistry for controlling reactor temperatures.
CO2 is also employed to neutralize alkaline effluents.
Carbon dioxide is used for inerting, chemical synthesis, supercritical fluid extraction (SFE), acidification (pH) of wastewater or product transportation at low temperature (-78 °C or -108 °F).
Cafein is removal from cafee using supercritical CO2.
Carbon dioxide can be used to add conductivity to ultrapure water, for CO2 snow abrasive cleaning of parts or residues on wafers. CO2 can

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Rank: 7
Score: 83.55606
Retrieved Text: Cold weather easily brings to mind hot chocolate, roaring fires, and snowmen, but the winter months also bring an increase in carbon monoxide poisonings.
Carbon monoxide is a deadly, odorless, tasteless, and colorless gas often referred to as the “invisible killer.” It is released whenever we burn fuels such as gasoline, wood, natural gas, and oil. This gas can build up when heating systems, gas appliances and vehicles, and generators are used or ventilated improperly. Every year in the United States, carbon monoxide poisoning is responsible for more than 430 deaths and approximately 50,000 emergency department (ED) visits.
Some individuals are more affected by exposure to carbon monoxide than others. Infants, pregnant women, the elderly, and people with respiratory conditions or heart disease are more susceptible to carbon monoxide poisoning. Carbon monoxide is harmful because it deprives the heart, brain, and other vital organs of oxygen. Poisoning can occur from prolonged exposure to lower concentrations or brief exposure to higher concentrations of carbon monoxide.
Signs of carbon monoxide poisoning may include headaches, dizziness, drowsiness, nausea, vomiting, chest pain, weakness, and confusion. Breathing in carbon monoxide can lead to clumsiness, blacking out, and even death. Carbon monoxide poisoning symptoms can easily be mistaken for the flu or the common cold, especially during winter months. Unlike the flu or the common cold, however, carbon monoxide poisoning symptoms may lessen after you leave the affected area.
The good news is that carbon monoxide poisoning can be prevented.

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Score: 79.55056
Retrieved Text: Natural gas appliances are typically very safe to use. But a malfunctioning appliance can create carbon monoxide gas, which can be deadly.
Carbon monoxide is produced when natural gas, propane or other fossil fuels fail to burn completely. Carbon monoxide, or CO, is a colorless, odorless gas.
Symptoms of carbon monoxide poisoning include dizziness, headaches, queasy stomach and drowsiness. Continued exposure can cause death.
Carbon Monoxide Safety Tips to use gas in your home or business.

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Rank: 9
Score: 79.37489
Retrieved Text: Carbon dioxide is a reliable, versatile and efficient fire fighting agent,a colorless,odorless,electrically nonconductive gas that is a suitable for extinguishing fires.
CO2 fire fighting systems are the preferred choice as an extinguishant for a multitude of critical facilities,widely used for power generation,Shipboard (Marine) Systems etc.
Low pressure fire suppression system and high pressure suppresion system are available,pls contact us for more details if you are interested.

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Rank: 10
Score: 78.40785
Retrieved Text: Hydrocarbons are burned, or combusted, primarily in engines, power plants and heating systems. Known more commonly as fossil fuels, the hydrocarbons humans burn are coal, natural gas and petroleum products. If combustion were 100 percent efficient and all hydrocarbons contained only hydrogen and carbon, the sole byproducts would be water and carbon dioxide. There are unintended waste products, however, and they cause environmental harm. Even carbon dioxide, which is a natural part of the atmosphere, becomes a pollutant when released in excessive amounts. The environmental liabilities associated with hydrocarbons provide incentives for the development of alternative energy sources.
The incomplete combustion of hydrocarbons, especially coal and diesel fuel, causes the release of altered hydrocarbons. These hydrocarbon pollutants, known collectively as polycyclic aromatic hydrocarbons, take a variety of forms. Some are quite toxic, known to harm aquatic life and cause cancer.
Incomplete combustion of hydrocarbons also results in carbon monoxide pollution. An odorless, colorless gas, carbon monoxide causes headaches and complications for people with heart disease. Carbon dioxide is always released when hydrocarbons are burned. It is a leading cause of global climate change and the acidification of oceans. Combustion of oil and coal, in particular, causes the release of nitrogen oxides and sulfur dioxide. These oxides combine with water and oxygen in the atmosphere, creating nitric and sulfuric acids, which return to Earth's surface as acid deposition, or "acid rain." Acid deposition harms aquatic organisms and kills trees. Because it makes certain nutrients, such as calcium and phosphorus, less available to plants, it reduces the productivity of ecosystems

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Rank: 11
Score: 77.449814
Retrieved Text: Protect your family from the dangers of carbon monoxide, an odorless, colorless, tasteless and highly toxic gas, with this wireless CO detector. The transmitter can send alarm, trouble, end-of-life, tamper and low battery condition messages to the panel, warning occupants and alerting our Monitoring Center. The CO Detector is wireless and programmed to connect to your system in minutes.Please note: CO detectors are not included and must be added to Protection, Home Automation or Video Plans. We recommend purchasing several to place outside of bedrooms and major living areas.
Protect your family from the dangers of carbon monoxide, an odorless, colorless, tasteless and highly toxic gas, with this wireless CO detector. The transmitter can send alarm, trouble, end-of-life, tamper and low battery condition messages to the panel, warning occupants and alerting our Monitoring Center. The CO Detector is wireless and programmed to connect to your system in minutes.
Please note: CO detectors are not included and must be added to Protection, Home Automation or Video Plans. We recommend purchasing several to place outside of bedrooms and major living areas.

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Rank: 12
Score: 76.94131
Retrieved Text: Often called the invisible killer, carbon monoxide is an odorless, colorless gas created when fuels (such as gasoline, wood, coal, natural gas, propane, oil and methane) burn incompletely. In the home, heating and cooking equipment that burn fuel are potential sources of carbon monoxide. Vehicles or generators running in an attached garage can also produce dangerous levels of carbon monoxide.
Use the resources below to make sure you are Carbon Monoxide safe!
The US Fire Administration provides good resources for Carbon Monoxide Safety.

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Score: 76.78661
Retrieved Text: Carbon monoxide is a by-product of incomplete combustion of fossil fuels and hydrocarbons. It is an odorless, colorless gas that can kill if a person is exposed to the gas for an extended period. Fortunately, we can help you prevent carbon monoxide poisoning.
Any heating system that uses hydrocarbons, such as fossil fuel or wood can produce carbon monoxide (CO) when burned. These include; space heaters, wood burning stoves, water heaters, fireplaces, furnaces and gas central heating among others.
As mentioned earlier, CO is an odorless and colorless gas, so you will neither see nor smell it. If you are exposed to CO for an extended period, you will start to experience dizziness, nausea, fatigue, headaches and irregular breathing. In short, you will experience all flu-like symptoms with the exception of fever. You know you have CO poisoning in your home if the symptoms disappear when you go out and reappear when you go back inside.
If you suspect you have CO poisoning in your home, the first thing you need to do is get out of the house. Be sure to evacuate all the occupants of the house, including pets. Since oxygen levels in your blood may be very low, it is important that you sit still for a couple of minutes. Meanwhile, you can be calling 911 for help. CO poisoning can easily be treated through oxygen therapy.
The most effective way of preventing carbon monoxide poisoning is installing CO detectors and alarms in every bedroom in the house as well as the living room. We know all

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Rank: 14
Score: 76.64013
Retrieved Text: In 2010, U.S. fire departments responded to more than 80,000 non-fire carbon monoxide incidents. In 2008 alone nearly 200 people died from carbon monoxide poisoning. Carbon monoxide (abbreviated CO) is a colorless, odorless, invisible gas given off when fuels such as wood, coal, natural gas and gasoline, burn. In homes, some of the most common sources of CO are heating equipment, generators, automobiles, stoves, ovens and dryers.
Fire Safety pt 2-carbon monoxide: The Quiet Killer | Dan Lawrie Insurance Brokers Ltd.

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Score: 76.60252
Retrieved Text: MILWAUKEE (June 11, 2013) — Hurricane activity this season is expected to be above average, according to a report released by Colorado State University. To help homeowners prepare for hurricane season, which started on June 1 and runs through Nov. 30, Briggs & Stratton Corporation (NYSE: BGG) is partnering with TV stations along the Gulf and Atlantic coasts to give away four 6250-Watt1 Storm Responder portable generators per market.
Introduced in spring 2013, the Storm Responder is designed for operation when a power outage occurs. The portable generator unit features a state-of-the-art control panel and is powered by a reliable Briggs & Stratton Professional Series™ OHV engine. Coupled with use instructions printed on the unit, simple diagrams indicate the correct oil and generator fuel types, what appliances can be plugged in and where the portable generator should be placed when in use.
Carbon monoxide (CO) is a tasteless, colorless and odorless gas and it is important to be mindful of its dangers while operating a portable generator. Even if exhaust fumes can’t be detected, the small engines that power portable units emit potentially harmful CO gas. If engine fumes aren’t able to exhaust in a safe manner, harmful effects — even death — can occur in a matter of minutes.
• Do not run portable generators inside homes, garages, basements, crawlspaces, sheds, or other partially enclosed spaces, even if using fans or opening doors and windows for ventilation. CO can quickly build up and linger for hours, even after the unit has been shut off.
• Always place portable generators

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Rank: 16
Score: 76.37241
Retrieved Text: Welcome to GDS Corp. Let us put our years of knowledge and experience to work for you in your commercial or industrial business. We specialize in the development and production of flame and gas detection systems, including the CO2 sensor your facility can depend upon.
For industries that utilize carbon dioxide gas, a CO2 gas sensor is an important safety addition. Industries that could benefit from CO2 sensors include refining, brewing, food processing, water and waste water recovery and power generation. GDS Corp CO2 sensors are state of the art, and deliver the best cost effectiveness, reliability and ease of use. Large or small, your business will receive the personalized service that GDS Corp is recognized for.
When determining the type of sensors needed for any application, GDS Corp experts will guide you through the decision making process.
Carbon dioxide (CO2) is a colorless, odorless gas composed of two oxygen atoms bonded to a single carbon atom. Green plants use carbon dioxide during photosynthesis to make sugars and other organic compounds needed for plant growth and development. CO2 is also a byproduct of fossil fuel combustion, the burning of vegetable matter, fermentation and other chemical processes.
Since carbon dioxide is an inert gas, electrochemical sensors which depend on the target gas reacting with the electrolyte in the sensor will not work. The most common technique for the detection is carbon dioxide is infrared absorption. Using technology similar to that used in infrared combustible gas detectors, and infrared CO2 gas sensor can be designed to detect concentrations of carbon dioxide from

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Rank: 17
Score: 76.157875
Retrieved Text: Home > Training > What is Carbon Dioxide?
Carbon Dioxide is a gas that is both colorless and odorless. Not only is CO2 produced naturally in the environment, but it can also be created through human activities like burning gasoline, oil, coal, and wood. Respiration increases the level of CO2 in air as an individual exhales.
The measure of carbon dioxide in a room signifies the amount of fresh air available. Common complaints due to uncomfortable levels of carbon dioxide include headaches, an increasing pulse rate, particularly high fatigue, and breathing difficulties. In extreme cases, high levels of carbon dioxide can induce heavy nausea, dizziness, vomiting, and even loss of consciousness however, this is very unlikely and nearly impossible in most residential buildings.
Note: The included diagram to the right illustrates that Carbon Dioxide concentration levels have raised at an alarming rate over the last 50 years.
Most homes usually contain levels of carbon dioxide ranging from 300 to 1,000 ppm depending on numerous factors such as how many people are occupying an area, ventilation, internal vegetation, and much more.

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Score: 75.920494
Retrieved Text: There are lots of potential gases that could exist in your home. Natural gas, radon, and gases and vapors released from household furnishings, carpeting, flooring and paints. But none of these gases are as dangerous as carbon monoxide.
Carbon monoxide is scary and may even be a matter of life and death, so it’s not something to joke about. Part of the reason it is so dangerous is because the gas is colorless, odorless, tasteless, and initially non-irritating. A by-product of burnt fuel, carbon monoxide can manuveur its way into your home when the heat exchanger on a gas furnace cracks, allowing carbon monoxide to leak. Depending on the size of the leak and the circulation in a home, carbon monoxide can lead to death very quickly, or it could cause symptoms that have been misdiagnosed as the flu, viral infections, and chronic fatigue syndrome, among other things.
If you do not currently have a carbon monoxide detector in your house, call McKinley Heating Service Experts Heating & Air Conditioning in Edmonton to purchase one. Ask our experts about affordable WiFi carbon monoxide detectors like the Nest Protect.
If you have a carbon monoxide detector, don’t forget to check the batteries on a regular basis. Testing should be done every 90 days, and the detector should be replaced every 3 to 5 years.
Carbon monoxide doesn’t have to be scary and with the proper steps you can be certain to receive alerts if there is any sign of carbon monoxide. Get the protection you need and call McKinley Heating Service

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Rank: 19
Score: 75.79739
Retrieved Text: Carbon dioxide (CO2) is a colorless and odorless gas that exists in the earth's atmosphere and which is dangerous in high concentrations. The proportion of CO2 in natural ambient air is about 0.04 % or 400 ppm. When humans and animals exhale this gas, it is quickly mixed with the ambient air, including in rooms that are well ventilated.
A high CO2 content becomes apparent in humans through rapid fatigue and loss of concentration. The negative effects become noticeable more quickly in small rooms in which there are many people (e.g. conference rooms).
In order to initiate suitable countermeasures such as an increase in the supply of fresh air, it is important in modern climate control systems to measure not only parameters such as relative humidity and temperature, but also the CO2 content. The concentration of CO2 is regarded as an important indicator for the quality of room air.
Installed in the climate zone.

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Rank: 20
Score: 75.69273
Retrieved Text: Vehicles powered by internal combustion engines produce two main types of greenhouse gas emissions: evaporative and tailpipe emissions.
Diurnal emissions generated in the vehicle’s fuel system are caused by changes in temperature throughout the day.
Emissions from the fuel system when a hot engine is turned off occur because of the residual heat volatilization factor of fuels.
Evaporative emissions while driving occur when the engine is in its normal operation.
Emissions at rest with a cold engine occur mainly because of the permeation of the fuel system components.
Hydrocarbon (HC)1 There are a variety of hydrocarbons or volatile organic compounds (VOC). Caused by an incomplete combustion process. VOCs are ozone precursors and some (such as benzene, formaldehydes and acetaldehydes) are highly toxic to humans.
Carbon monoxide (CO)2 CO is a colorless, odorless gas. Caused by incomplete combustion and when carbon in fuels are partially oxidized. CO adheres easily to hemoglobin in blood and reduces the flow of oxygen into the bloodstream causing alterations in the nervous and cardiovascular systems.
Carbon dioxide (CO2)3 Caused when combustion is completed in the presence of sufficient oxygen to oxidize fuel’s entire carbon. Carbon dioxide poses no threat to health but it is a greenhouse gas with a significant heat-trapping factor and contributes considerably to global warming.
Nitrogen oxides (NO)4 Nitrogen oxides, like hydrocarbons, are ozone precursors. In the presence of humidity, NO are converted into nitric acids, thus contributing to acid rain. When both the pressure and temperature in the engine are high, the nitrogen atoms and oxygen react to form NO, nitrogen dioxide (NO2) and other nitrogen

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Rank: 21
Score: 74.97606
Retrieved Text: In order to keep you and your family safe, it’s wise to invest in a reliable carbon monoxide detector. High levels of the gas can cause serious health risks for anyone who’s exposed, especially if the exposure happens repeatedly, such as small amounts over weeks, months, or years. What is Carbon Monoxide? Carbon Monoxide is a gas that’s both odorless and colorless, so you can’t detect it with your senses. It is found in many natural sources, such as forest fires, volcanoes, and more. Several products also emit carbon monoxide, such as stoves and other household appliances. When ignited, carbon monoxide is easy to see because it burns with a blue flame. What is Carbon Monoxide Poisoning? Carbon monoxide is harmless at low concentrations, but at higher concentrations it’s extremely dangerous to both people and animals. When too much is inhaled, carbon monoxide poisoning will result. This can lead to confusion, dizziness, headaches, memory loss, brain damage, heart problems and much more. In extreme cases, it can also cause death. In a pregnant woman, carbon monoxide poisoning can also have serious health risk to the fetus. Carbon Monoxide Detectors Since carbon monoxide is colorless and odorless, it cannot be seen or smelled. Carbon monoxide detectors were invented to solve this problem. These detectors can measure the concentration of carbon monoxide in an environment and sound an alarm if the levels reach dangerous quantities. They’re available in a wide range of models to suit the specific needs of each individual and family. Some models have visual indicators,

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Retrieved Text: The EPA sais Carbon Dioxide is Bad for the Environment. And our Representatives want to tax us on this "Carbon Foot print" in other words Taxing you to breath.
atoms covalently bonded to a single carbon atom. It is a gas at standard temperature and pressure and exists in Earth's atmosphere in this state. CO2 is a trace gas being only 0.038% of the atmosphere.
CO2 is an acidic oxide: an aqueous solution turns litmus from blue to pink. It is the anhydride of carbonic acid, an acid which is unstable and is known to exist only in aqueous solution. In organisms carbonic acid is produced by the enzyme, carbonic anhydrase.
For more details on this topic, see Carbon dioxide (data page).
Carbon dioxide is colorless. At low concentrations, the gas is odorless. At higher concentrations it has a sharp, acidic odor. It will act as an asphyxiant and an irritant. When inhaled at concentrations much higher than usual atmospheric levels, it can produce a sour taste in the mouth and a stinging sensation in the nose and throat. These effects result from the gas dissolving in the mucous membranes and saliva, forming a weak solution of carbonic acid. This sensation can also occur during an attempt to stifle a burp after drinking a carbonated beverage. Amounts above 5,000 ppm are considered very unhealthy, and those above about 50,000 ppm (equal to 5% by volume) are considered dangerous to animal life.
At standard temperature and pressure, the density of carbon dioxide is around 1.98 kg/m3, about 1.5 times that of air.

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Rank: 23
Score: 73.86533
Retrieved Text: Corporate Average Fuel Economy – a standard and limitations instituted to improve the gas mileage of cars and light trucks and thereby reduce energy consumption. CAFE is administered and regulated by the National Highway Traffic Safety Administration (NHTSA) in conjunction with the EPA.
a legal or political system that sets specific mandatory limits on specified emissions, such as CO2 and enforcement actions coupled with a free-market based mechanism whereby emitters can purchase, sell, and trade emission.
a generic term representing Certified Emission Reduction. A unit of measurement and sale that is a key component to the market-based mechanism of a cap and trade system. A single Carbon Credit is equal to one metric ton (tonne) of sequestered carbon dioxide, or its equivalent in Greenhouse impacts for other chemicals such as methane. Carbon Credits are used in both industrial and personal carbon trading systems.
the repeating, natural process of carbon storage (sequestration) and emission.
an odorless, colorless, nonpoisonous, and naturally occurring gas that is a product of fossil fuel or organic material combustion.

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Rank: 24
Score: 73.843254
Retrieved Text: We include this important testing as part of the normal home inspection. Carbon Monoxide (CO) is the leading cause of accidental poisoning deaths in the United States. It is a colorless, odorless, and tasteless poison gas that can be fatal when inhaled, and it is known as “the silent killer” because it cannot be seen, smelled, or tasted.
CO is produced by furnaces, common household appliances, unvented kerosene and gas space heaters, automobile exhaust, generators, fireplaces, and other systems that are powered by the burning of fuel that includes, but is not limited to, natural gas, propane, gasoline, oil, and wood.
The Consumer Product Safety Commission provides information about this subject at their website cpsc.gov.

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Rank: 25
Score: 73.63216
Retrieved Text: Everyone should have smoke alarms and carbon monoxide detectors in their homes. Carbon monoxide, or CO, is an odorless, colorless gas that can cause sudden illness and death.
Choose smoke alarms that communicate with each other, so that if one alarm sounds they all will.

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Rank: 26
Score: 73.27507
Retrieved Text: Carbon Monoxide Is A Deadly Gas That Can Kill! Keep Your Family Safe With A Carbon Monixide Detector and smoke detectors.One of the first lines of defense against deadly fires and smoke, is having working smoke alarms throughout your home and living area. A second very important monitoring device to have in your home is a carbon monoxide detector.What is Carbon Monoxide?Carbon monoxide (CO) is a colorless, odorless, poisonous gas. A product of incomplete burning of hydrocarbon-based fuels, carbon monoxide consists of a carbon atom.

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Retrieved Text: ﻿﻿DON’T LET YOUR GAS APPLIANCES STARVE FOR AIR!
Gas appliances, such as water heaters, furnaces and boilers, need plenty of air to operate safely. Otherwise, they will produce excessive, deadly carbon monoxide. Carbon monoxide is odorless, colorless and toxic, which means you can’t see, taste or smell it. It causes headaches, dizziness, disorientation, nausea and fatigue. Carbon monoxide can also kill, so be sure to maintain your gas appliances!!
Have vents and chimneys inspected by a qualified expert at least once a year.
What is the most important thing to remember when installing a smoke alarm or carbon monoxide (CO) alarm? LOCATION, LOCATION, LOCATION!
Consider installing a Carbon Monoxide alarm in the hallway outside of each sleeping room area.
Check the manufacturer date on your smoke alarm. Consider replacing if it is over 10 years old.

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Rank: 28
Score: 72.15863
Retrieved Text: The average adult breathes in 20,000 liters of air every day. Within those 20,000 liters are pollutants from automobiles, industrial plants, and various other sources. Breathing in such pollutants can cause a number of different respiratory problems and even cancer. While there isn’t much we can do about the air outside, there are steps we can tell our clients to take to make sure the air within their home is clean.
Keep things that cause pollution out of the home. Secondhand smoke is among the most dangerous air pollutants, so do not allow smoking indoors. Also, avoid storing certain chemicals and allowing excess moisture in the home.
Install a carbon monoxide detector. Carbon monoxide is also one of the most dangerous air pollutants and it claims the lives of hundreds of people each year. Without a carbon monoxide detector, it can go unnoticed as it is a colorless and odorless toxic gas. To avoid exposing the home to high carbon monoxide levels do not leave the car idling running in the garage.
Test for radon. Radon is the leading cause of lung cancer in nonsmokers and the second-leading cause of lung cancer overall. Much like carbon monoxide, radon is a colorless and odorless gas which can only be found by testing. Second-hand smoke, carbon monoxide, and radon are the three most deadly air pollutants in the home and folks must take steps to protect themselves as well as their family. You should also fix leaks, clean air conditioners and dehumidifiers, and properly ventilate your home to improve air quality.
May

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Retrieved Text: Services were held Saturday for three of the five teens killed two weeks ago in a Hialeah, Florida hotel room, when deadly carbon monoxide fumes seeped into their room. The Miami Herald reports that the five friends were celebrating a birthday at the Hotel Presidente, when they left their borrowed car running in the attached garage.
The Associated Press reported that friends of the deceased told police the car was having engine trouble so they likely left it running to avoid it not starting again. The door leading to the garage was slightly ajar, allowing the fumes to enter the hotel room, and the teens were found by a hotel maid the next day. She reported a strong smell of gasoline and saw that they were sprawled out on the floor, looking unconscious and not responding to her when she shouted ‘hello’.
In 2006, Florida law was changed to require installation of carbon monoxide detectors in new buildings. The Hotel Presidente (and other such older buildings) is exempt unless it undergoes major renovations. It is yet unclear whether a separate Hialeah ordinance was violated, which requires a higher level of carbon monoxide detection in older buildings.
USA Today reported the story, adding statistics and tips from the Centers for Disease Control and Prevention: Carbon monoxide, a colorless odorless, tasteless gas kills more than 400 people in the U.S. each year, with 15,000 related emergency room cases.
• Have your heating system, water heater and any other gas-, oil-, or coal-burning appliances serviced by a qualified technician every year.
The gas is

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======= Instance Index 646 =========
Input Text: Answer the following question given this paragraph: 

birth of dizygotic (or fraternal) twins. Because dizygotic twins develop from two eggs fertilized by two sperm, they are no more identical than siblings born at different times. Much less commonly, a zygote can divide into two separate offspring during early development. This results in the birth of monozygotic (or identical) twins. Although the zygote can split as early as the two-cell stage, splitting occurs most commonly during the early blastocyst stage, with roughly 70–100 cells present. These two scenarios are distinct from each other, in that the twin embryos that separated at the two-cell stage will have individual placentas, whereas twin embryos that form from separation at the blastocyst stage will share a placenta and a chorionic cavity.


Q: Because dizygotic twins develop from two eggs fertilized by two sperm, they are no more identical than siblings born at what?

 Choices:

- other times of day

- different times

- other eras

- different places

A:

Target Text: different times

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Rank: 0
Score: 91.59169
Retrieved Text: A zygosity will determine if twins, triplets, etc. are identical or non-identical (fraternal).
The results issued for a zygosity test will be either identical whereby the tested individuals have identical DNA at the tested regions or fraternal whereby the tested individuals do not have identical DNA at the tested regions.
Identical twins (also called monozygotic twins) occur when a single egg is fertilized by a single sperm and the egg subsequently divides into two separate embryos. Identical twins will have identical DNA at the regions tested. Non-identical/fraternal twins (also called dizygotic twins) typically occur when two eggs are fertilized by two different sperm. Fraternal twins are as genetically similar to one another as any siblings that share both parents, but will not have identical DNA at the regions tested.

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Retrieved Text: Identical — or monozygotic — twins pop up from a single fertilized egg that eventually splits in two and forms two identical boys or two girls. They share 100% of their DNA.
Fraternal — or dizygotic — twins form from two eggs that have been fertilized by two of the father’s sperm, producing two genetically unique siblings. They share 50% of their DNA.
But “semi-identical” twins are so rare, experts say they have only identified two cases — ever.
Right along that DNA-sharing spectrum, “semi-identical” twins share anywhere from 50% to 100% of their genomes, researchers say.
And they’re extremely, extremely rare. The only other reported case of sesquizygotic twins was reported in the United States in 2007. The recently identified twins from South East Queensland are now 4 years old and healthy.
Details of this second case were published this week in the New England Journal of Medicine. Researchers from the University of New South Wales and the Queensland University of Technology combed through nearly 1,000 cases of twins to confirm their findings.
Authors of the study were observing a 28-year-old woman’s pregnancy in 2014 when they noticed her set of twins shared a placenta, appearing to be identical twins.
But the 14-week ultrasound showed they were different genders — making it impossible for them to be monozygotic twins.
These twins were formed when a single egg was fertilized by two sperm — something that shouldn’t happen, Dr. Nicholas Fisk, who participated in the study and serves as the deputy vice chancellor of research at the University of New South Wales, told CNN.
That’s

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Retrieved Text: The development of monozygotic twins arises through a singular, fertilized embryo, splitting into two. A fertilized embryo develops from a zygote, which is formed through the fusion of a singular egg, with a singular sperm. As monozygotic twins develop through this splitting of a single embryo, both individual twins share identical chromosomes. As such, their genetic codes are identical. Given this identical genetic code, monozygotic twins are therefore called identical twins, or are sometimes referred to as maternal twins.
As each monozygotic twin comes from the same embryo, both individuals have the same gender. The conception of monozygotic twins is relatively rare, with the approximate birth rate of conceiving monozygotic twins being only 3 in every 1,000 pregnancies. The separation degree between the twins, inside of the uterus, is dependent upon time. This means that the separation of both the amniotic sac (amniosity), and the chorion (Chorionicity), depends on the moment in time that the separation occurs.
A third of all monozygotic twins develop from a separate placenta, and an amniotic sac, within the uterus. In this situation, they are known as dichorionic-diamniotic twins or Di-Di twins. These Di-Di twins form through a splitting of the singular embryo, in a 2-3 day time period following fertilization. Two-thirds of all monozygotic twins actually share a singular placenta, with two independent amniotic sacs. These are called monochorionic-diamniotic twins or Mono-Di twins. Mono-Di twins form through the splitting of an embryo in a 3-8 day period following fertilization. Approximately 1% of all conceived monozygotic twins, also share an amniotic sac, and

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Retrieved Text: It is not often that one encounters a pair of “semi-identical twins.” In fact, the world has only seen two of cases of this phenomenon ever before in history. While we have all heard of fraternal and identical twins, the term “semi-identical” twins is puzzling. What exactly does that mean?
By definition, identical twins are created from a single fertilized egg that eventually splits in two and forms two identical males or two identical females. In this case, they share 100% of their DNA. On the other hand, fraternal twins are created from two fertilized eggs from two of the father’s sperm, producing two genetically unique siblings. They share 50% of their DNA. Interestingly, “semi-identical” twins will share the same identical DNA from one parent, but not from the other. The first pair was born in the United States in 2007. The second pair, although born in 2014, was recently discovered in Australia.
The discovery was actually made before the twins were born in 2014. In early pregnancy (at about 6 weeks), a single placenta had indicated that the expectant mother was going to have identical twins; however, an ultrasound at 14 weeks showed the twins were male and female, which would then make it impossible for the pair to in fact be identical. Consequently, doctors determined that a single egg must have been fertilized by two sperm before it divided thus resulting in “semi-identical” twins. The researchers who were responsible for the discovery of the twins screened approximately 1,000 pairs of fraternal twins to see if this

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Retrieved Text: There are several types of twin placentas in the human race. You will be surprised to know that not all twins share a placenta and sometimes two of them will merge to become one. To really understand how all this magic happens, you need to understand the different types of twins, how they are conceived and how they are positioned in their mother’s wombs. Let us take a look at the different types of twins.
Dizygotic twins are those that result from the fertilization of two eggs by two different sperms. They are known in layman’s terms as fraternal twins. These are like two siblings who share 50 % of genes unlike identical twins who have the same DNA. Each fetus will lie in their own membrane and will not share any vessels with the other. They lay in different amnion and each of them has their own sac.
The two fetus do not share the same placenta. Each has their own set of blood vessels and their own amnion. In this case there will be two different placentas released after birth. You will also notice that the two placentas in some cases will merge to form one placenta. Though it is not common enough to be the standard it is not very unusual as well. All the dizygotic twins are di-chorionic. This just means that they have different placentas and different sacs. The sacs can be fused, sharing amniotic fluid or completely separated.
These are the result of one egg being fertilized by one sperm. The fertilized egg

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Retrieved Text: After giving birth to twin girls, a mother in the case T.M. v. A.S. sought child support from the man she believed to be the father of her babies, A.S. The Passaic County Board of Social Services filed an application on behalf of the mother to establish paternity. The court ordered DNA tests from A.S. in order to ascertain his paternity and therefore to compel him to pay child support.
In a very rare but scientifically possible occurrence, the paternity test determined that A.S. was only the father of one of the twins. This phenomenon is known as heteropaternal superfecundation, where two eggs are released during the same cycle, and each egg is fertilized by the sperm of a different man. Heteropaternal superfecundation, which is widely accepted in the scientific community, essentially produces fraternal twins with different fathers. The twins are considered heteropaternal dizygotic twins.
The mother here admitted to having slept with A.S. and with another man within a week of each other. Evidently, she released more than one egg during the period of time in which she slept with both men. One egg was fertilized by A.S.’s sperm, and the other was fertilized by the other man’s sperm. Though they are twins, the girls born of this heteropaternal superfecundation occurrence are only half-sisters.
A situation like this one has not previously come before the courts in New Jersey. The court found that the method of the DNA collection and testing was done correctly, and therefore the paternity results were reliable and accurate. Consequently, the court decided that

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Retrieved Text: You may have heard about the "twin effect," a correlation between taking birth control pills and twinning. It is theorized that if you conceive shortly after you stop using birth control pills, your chances of having twins increases. While using birth control pills, ovulation is suppressed. When they're discontinued, it's thought that the ovaries may superovulate, releasing more than one egg in a cycle and increasing the opportunity to conceive dizygotic or fraternal twins.
This concept is primarily based on a 1977 study published in the New England Journal of Medicine that showed women who got pregnant shortly after stopping oral contraceptives were twice as likely to have twins. These twins were generally dizygotic (fraternal), rather than monozygotic (identical).
Dizygotic twins form when two separate eggs are fertilized by two separate sperm, supporting the idea that the ovaries were releasing multiple eggs in response to stopping contraceptive pills. According to the study, after being off the pill for several months, ovulation should return to a normal pattern of one egg per month, and the chances of twins are reduced to normal levels.
The "twin effect' hasn't been researched a whole lot since that 1977 study in the New England Journal of Medicine, and what little research there is has been mixed. One 1989 study even concluded that getting pregnant within a year after taking oral contraceptives slightly increases your chances of monozygotic (identical) twins. Yet another large study in 1987 showed no association between twins and taking oral contraceptives.
Anecdotally, many moms of twins cite getting pregnant shortly after stopping

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Retrieved Text: Before I got pregnant, I worried constantly if I was going to get pregnant with twins because twins run in my family. I worried even more after I started taking fertility drugs. Having one baby was daunting enough, but the idea of being pregnant with two seemed to quadruple my nerves and fear. What would I do with twins in my tiny New York City apartment? Keep one in a drawer? The twins are on my mother's side, but are twins from the mom or the dad?
It turns out that it's not only genetics that matter, but also the type of twins being discussed. In my family, the most recent set of twins was identical, which, according to Stanford University, is a freak occurrence that just happens sometimes when a fertilized egg splits. However, fraternal twins, the type born of two separate fertilized eggs, are genetic. According to Stanford, the likelihood of twins during any particular pregnancy comes from the mother, because, as they put it, "A father’s genes can’t make a woman release two eggs."
If you're the woman who is trying to conceive though, it's not just your mom's genetics that matter. You can inherit the trait from your father. Your partner's sperm may having nothing to do with it, but your father's DNA does, according to Science Mag.
According to Columbia University's Go Ask Alice, "There are certain genes involved in ovulation that induce hyper-ovulation, or the release of multiple eggs. If you have these genes, your chances of fertilizing two different eggs by two

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Retrieved Text: Young Brisbane twins, a boy and a girl, have been identified as only the second set of semi-identical, or sesquizygotic, twins in the world—and the first to be identified by doctors during pregnancy.
"It is likely the mother's egg was fertilized simultaneously by two of the father's sperm before dividing," said professor Fisk, who led the fetal medicine team that cared for the mother and twins while based at Royal Brisbane and Women's Hospital in 2014. Professor Fisk, a past president of the International Fetal Medicine and Surgery Society, worked alongside Dr. Gabbett.
"The mother's ultrasound at six weeks showed a single placenta and positioning of amniotic sacs that indicated she was expecting identical twins. However, an ultrasound at 14 weeks showed the twins were male and female, which is not possible for identical twins."
Identical twins result when cells from a single egg fertilized by a single sperm divide into two, so identical twins are the same gender and share identical DNA. Fraternal twins occur when each twin develops from a separate egg and the egg is fertilized by its own sperm.
Dr. Gabbett said if one egg is fertilized by two sperm it results in three sets of chromosomes, one from the mother and two from the father. "Three sets of chromosomes are typically incompatible with life and embryos do not usually survive," he said. "In the case of the Brisbane sesquizygotic twins, the fertilized egg appears to have equally divided up the three sets of chromosomes into groups of cells which then split into two, creating the

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Retrieved Text: Home / Video / Viral / world / Nanganak ng Kambal ang Babaeng ito Pero Magkaiba ang Ama! Paano ito nangyari? Alamin!
Nanganak ng Kambal ang Babaeng ito Pero Magkaiba ang Ama! Paano ito nangyari? Alamin!
Twins are normal. We are all aware of the two kinds of twins: identical twins who look exactly alike, and fraternal twins that don't look alike.
But what do you call a phenomenon with twins having the same mother, yet different fathers?
We know that identical twins happen when a sperm cell entered an ovum which was about to undergo mitosis.
Meanwhile, fraternal twins are conceived when two ovums are ready and are fertilized by different sperms.
But having twins with different fathers, or bi-paternal twins isn't a scientific impossibility.
That's proven by a couple from Vietnam.
For privacy purposes, the name of the people involved will not be disclosed as part of the confidentiality clause with the Genetic Association of Vietnam who conducted a DNA test in Hanoi.
Why does your twins look different?
Yes, they were born on the same day, with the same gender, with only a few hours apart.
At first, they thought that it was only a normal case of fraternal twins. But they can't be more wrong.
Growing up together, the twins started exhibiting more differences between each other. One hild has a thick, wavy hair, while the other has a thin straight hair. The former did not resemble the father at all-- which prompted the father's family to pressure him into getting a DNA test. The worst case scenario for them was a hospital mix

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Retrieved Text: You’ve had the usual pregnancy symptoms, done the tests, and gone for pregnancy ultrasounds – and now you have found out that you have a twin pregnancy. How do you feel? What are the differences between a single pregnancy and being pregnant with twins? And is there anything you need to do differently?
There are two main categories of twins – fraternal, or dizygotic twins, and identical twins. Fraternal twins are caused by two eggs being fertilised at the same time. Hence, you can have a boy and a girl, or two siblings who don’t resemble each other at all. Identical twins, on the other hand, come about when one egg splits into two. Identical twins conform to the stereotype of being so similar that you can’t tell them apart and being very close. Fraternal twins, on the other hand, can be so different that they are like any other pair of siblings. This is especially true if they are a boy and girl – they often end up going to different schools and do not share the same interests.
The genetic factor when conceiving twins is very much a matter of debate. The main known genetic factor is hyper ovulation, which could be the cause of fraternal twins and could indeed be inherited. Such a factor has not been established when it comes to identical twins. Nonetheless, it is interesting to note that in some families twin births seem to be very common, while other families don’t seem to have any twins at all.
Another cause of twin

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Retrieved Text: Genetic Basis of Homosexuality Research Papers examine the research and study presented by Pillard and Bailey on the relation of genetics and homosexuality.
The genetic basis of homosexuality can be explicated in research papers from the writers at Paper Masters. Our writers will examine studies on the genetic basis of homosexuality and review and report on them for you in a research project.
Identical twins are called monozygotic twins and their genomes are identical.
Fraternal twins are called dizygotic twins and they share as much genetic material as other siblings.
Richard Pillard of Boston University and Michael Bailey of Northwestern University performed a study with 56 monozygotic twins, fifty-four dizygotic twins, and fifty-seven adoptive brothers who were unrelated. The use of twins is important because they genetically related twins share genetic material while the adoptive brothers do not.
If there is a genetic component to sexual attraction, then the more genetic material that two people share, the more likely they are to exhibit the same sexual preference. Pillard and Bailey’s study showed a concordance rate of 52 percent for monozygotic twins, 22 percent for dizygotic twins, and 11 percent for the adoptive brothers. Concordance is the sharing of a trait by each twin. The results of the study indicate a genetic component to homosexual attraction. Genetics could be as much as 70% of the cause of sexual preference. Pillard and Bailey believe that other factors are both biological and environmental and that they manifest themselves early in life. Their study could not determine how many genes were involved in sexual preference.

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Retrieved Text: Don't be too down on yourself, maybe he just looks like a girl.
what movie we referring to??
nah, Twelfth Night should get the credit!
If she keeps getting mistaken for her brother, I would have to say that they do.
It's possible they have similar facial features and skin color/ hair color, and if they wear similar clothing, it can be difficult to tell even fraternal twins apart.
Good point; I stand corrected on the twin thing, but you said they don't look anything alike. I think we're talking about two different things here.
its possible for identical twins to be different genders, one will normally just look slightly more feminine in body structure.
identical twins cannot be different genders. they are split from the same egg meaning their DNA is identical at the point of conception including their chromesones.
fratenal twins are basically two babies that share the womb. two seperate eggs and sperm.
20 are you sure it's different eggs as well? I thought it was just different sperm same egg, then again I never looked into it. If what I said is true, then they share all of their mother's genes, which means more similarities than normal siblings.
having researched a wee bit yoy can have very rare cases of identical twins where one is male and one is female. it is caused by a mutation in one male twin. identical refers to the zygote meaning they have ti be from the same zygote.
You guys made a bid deal out of nothing.
Actually identical twins are always the same gender. Contrary to common

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Retrieved Text: They say that no birth control method is 100 percent foolproof, but it has always been assumed that abstinence is the only time that guarantees you won't get pregnant. But what if you are already expecting? Can you get pregnant if you are already pregnant?
The answer is mostly no, you can't get pregnant if you're already pregnant. However, there is a phenomenon called superfetation, where a second egg is released and fertilized, sometimes weeks or months after the first. To note: This is extremely rare, with only a few cases reported in medical history, but it theoretically can happen.
In almost all women, as soon as the fertilized egg is implanted, hormones are secreted that shut down any future ovulation and that start a mucous plug being formed at the cervix, serving as a barrier to any sperm who are hoping to enter, according to The Pregnancy Zone. But there have been a few cases, like Julia Grovenburg of Arkansas, where superfetation may have occurred. Julia knew she was pregnant and went for an early ultrasound, where the doctors saw one sac which they were able to give an estimated gestational age. Then they heard a smaller, second heartbeat and discovered a second baby who appeared much younger developmentally.
According to Dr. Karen Doyle, who was interviewed on ABC-TV, while twins may have different sizes at birth, it's unusual for them to have different sizes very early in the pregnancy. Dr. Doyle felt that superfetation was a possible explanation. However, Jeffrey Kuller, M.D. of Duke University told WebMD

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Retrieved Text: Welcome to Season One of Double Happiness Multiplied.
On Episode One, Part One, we get clear on what type of multiple you’re carrying and what that means for your pregnancy.
We hear from Maternal-Fetal Medicine Specialist Associate Professor Craig Pennell who clears up some of the misconceptions surrounding whether your babies are identical or not, and how oftentimes your sonographer or obstetrician might give you a misdiagnosis.
Rebecca Perrie shares her story of going through her twin pregnancy thinking she was carrying fraternal, or non-identical twins, to only find out later on that her girls are in fact identical.
Jodie Wiren takes us on her journey with one of the rarest types of multiples – Monochorionic Monoamniotic twins or MoMos.
Also, Hypnobirthing Practitioner and Doula Elyse Jamieson tell us how when she found out she was expecting fraternal twins, she was determined to learn everything she could in order to make confident decisions that were specific to her situation.
And, I share my story about the shock of learning that I was carrying identical twins and that there were serious complications.
On part two of this episode, we’ll focus on Higher Order Multiples. Laura Sarubin tells us about her journey with identical triplet girls and Jannelle Snaddon explains how she had to grow a uterus to have a baby and ended up with quadruplets.
By the end of Episode One, you’ll be quite familiar with terms like Zygosity, Chorionicity, and Placentation so you’ll have the knowledge you’ll need to be proactive when attending your medical appointments.
A zygote is a fertilised egg.
Fraternal twins are Dizygotic,

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Retrieved Text: I read an incredibly heartwarming story the other day that was first reported in the summer of 2017. A Nigerian couple were trying to conceive for 20 years with no success.
They would’ve been happy to have just a single precious child. They weren’t even considering how to conceive twins. Many in their position would’ve given up and simply accepted that it was never going to happen.
However, the couple still believed and were finally rewarded. Not with 1 child, not with twins but with six babies! I had to even check the name for six, sextuplets!
That got me to thinking, is there reason they had more than just one baby? Did their years of trying make twins more likely?
When I researched a bit more, I found that there are even towns that are famed for their high twin rate. Mohammadpur Umri, a small village in India, has a total of 33 pairs of twins, which doesn’t seem particularly high, until you learn that there are just 600 people living in this village!
While scientists have managed to do various tests, they’ve not yet pinpointed why there is such a high twin rate in the village, it can’t simply be chance?
Has anyone been able to discover the secrets to having twins? Why did the Nigerian couple have 6 children when they finally managed to conceive? Why is there such a high twin rate in some areas?
Based on our curiosity, we’ve found that there are range of reasons, some based on science, other not… We’re now going to detail some

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Retrieved Text: This is lecture unit two and this is the third module.
a little bit later, we'll be talking about alternatives to twin studies.
you an overview of what twin studies in psychology have found.
Recall that a twin study is a natural experiment.
whatever trait we'll measure that phenotype.
important in shaping individual differences on that phenotype.
something, a little something about the feasibility of twin studies.
this lecture, we talked about the frequency of twins.
Twins are actually extraordinarily frequent.
So twins are there, but how do twin researchers go about finding twins?
the world, published a special issue on twin registries throughout the world.
on the world map is actually a twin registry.
every continent is represented, except may be South America.
in this special issue of this journal on twin registries.
in research and all these different sites throughout the world.
Twin research is a very active area of research.
to identify twins through the public health systems.
For example, I work in Denmark and in Denmark, we have a twin registry.
And, every twin in the country is registered in that twin registry.
to the registry and identify where they're living now, and we contact them.
that, but it's relatively easy to identify twins.
health systems, it might be a little more difficult to identify twins.
with a variety of ways of doing this.
happened to be public records, in the state of Minnesota in the US.
through special clubs run for mothers of twins.
So, there's a lot of ways of systematically ascertaining twins.
samples of twins in order to undertake twin studies.
looking at the studies is, well, how do you tell twins apart?
sure that this is

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Retrieved Text: There would be few women in the world who would feel ready to be pregnant with triplets. When they are told the news and immediately think to themselves, "Ok, I've got this." For the majority, the news would come as a huge surprise and you would feel a mix of emotions including, amazement, joy, shock, fear, disbelief and how... as in, OMG! How did this happen?
According to the Australian Bureau of Statistics, 309,142 births occured in 2017. Of these, there were just under 60 sets of triplets born.
Dizygotic - they are formed from separate eggs, that is with a set of identical (2) and a fraternal (1) triplet.
Polyzygotic - there is a set of identical (or monozygotic) twins conceived and another egg is released which is then fertilised by another sperm.
READ NEXT: Celebrities you didn't know were twins!
What are the odds of conceiving triplets?
The most likely way to conceive with triplets is to have fertility assistance and/or take medication which increases ovulation. There does not seem to be any scientific evidence to support the theory that having identical multiples is influenced by heredity. It seems that the splitting of a fertilised egg happens at random.
But hyper ovulation (where the ovaries release more than one egg each month) is certainly influenced by genetics, so women who come from families where non-identical multiples are common do have more chances of having their own multiple births.
Statistics vary but some research suggests conceiving triplets naturally occurs 1 in every 9000 births. Via fertility assistance, the likelihood increases to around 1

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Retrieved Text: “Gambling addiction can be inherited,” the Daily Mail reported. The newspaper said, “if one of your parents is addicted to gambling the odds are high that you will be as well, research has revealed”.
This study in 2,889 pairs of twins investigated the role of genetic and environmental factors in the development of gambling addiction. The researchers were particularly interested in whether these factors interact in the same way in women’s gambling addiction as in men’s.
The study found that identical twins who were gamblers were more likely to have a twin who was also a gambler than non-identical twins. The researchers suggest that this association was more to do with a genetic link than environmental factors.
This study suggests there is a genetic component to gambling addiction that can be present in both men and women. However, this study did not address which genes may be involved or the strength of the association. Addictions are complex disorders. If some people do have a genetic predisposition to develop addictions, it is unlikely to be the sole cause of the addiction and environmental factors are also likely to be involved.
The study was carried out by researchers from the University of Missouri and the Queensland Institute of Medical Research. It was funded by the US National Institutes of Health. The study was published in the peer-reviewed medical journal Archives of General Psychiatry.
The researchers say that women represent nearly half of all individuals who are in treatment for gambling addiction. They wanted to investigate the causes of this addiction in women and

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Retrieved Text: There is more risk of having multiple babies is increasing with the IVF treatment and also with the drugs used at the time of infertility treatment. There are about 30 to 40 percent of infertility drugs leads to multiple births of triplets at the time of IVF. This is directly related to the practice of transferring multiple embryos at embryo transfer.Multiple births are related to increased risk of pregnancy loss, obstetrical complications, prematurity, and neonatal morbidity with the potential for long term damage.
Currently, after IVF and intra-cytoplasmic sperm injection (ICSI) around 16% of pregnancies are multiples, compared with only 1–2% after natural conception. This can be directly related to more than one embryo being transferred during IVF and ICSI.
If two separate embryos implant in the womb, the mother will be pregnant with non-identical twins.
The chance of a single embryo dividing and resulting in identical twins is also higher after IVF, particularly after blastocyst transfer. However it is not yet known why this happens. So it is possible to end up with twins from the transfer of a single embryo, or triplets from two embryos.
There is almost 15% of babies born as a result of IVF to women under 35 (using fresh eggs) are multiple births.
The numbers of embryos that can be transferred is no more than two for women under 40 or no more than three for women over 40, the aim for all patients should be to have a single healthy birth.
Because of this all clinics must now have a strategy to minimize the risk

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Retrieved Text: It's baby mania! Who can resist the cuddly cuteness of a baby? It inspires only gushes of awe at the miracle of birth and hope for another generation. And what about twins? So cute! Triplets? Cuter! Sextuplets? Can we take them home? How is it that babies of multiple births are more like kittens of a litter than people? A discussion for another time. There are two trends in pregnancy that are making headlines more and more frequently. The first is that women are waiting longer to have babies. This means that more and more women are older when they have their first child. The second is that there are more and more women having multiple births--twins, triplets, quadruplets, sextuplets, etc. From the individual woman's standpoint, it makes sense--establish your career and other dreams while you're young, then have a child that you can comfortably raise in this financially troublesome world. From a sociological standpoint, there are broader ramifications on the balance of society.
First let us clarify some points. I don't know if the average age of first pregnancy is rising or falling. That more and more women delay pregnancy into their thirties and forties would suggest that the average age should be climbing. But taken with the data that the average age of first sexual experience is falling over time, you would expect that many females are getting pregnant earlier as well. I would believe that the average age of first pregnancy is not changing much at all. I would believe that the ranks are

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Retrieved Text: Someone actually asked me if I planned on having twins! Yeah, I made an extra egg drop (despite not being on fertility drugs), my husband willed his swimmers to go for both eggs, and we magically made the two eggs implant. Sure! We TOTALLY planned it!
Comments for Did You Plan On Having Twins?
Our response to this is to tell people we 'did it' twice on the same night!
After someone suggesting that it must have been a 'rough' (ie shot his sperm up there fast hence causing the egg to break) conception we just use the response that my partner caused the egg to break when asked if we planned our twins. Shuts people up & funny if they believe us.
We get asked if we'd still have chosen to have a baby if we'd known it would be twins seeing as we have 4 children between us already.
I just like to say that one was an accident.
I haven't gotten this one yet. I'm 12.5 weeks with identical twins, so I would have to ask them how they think I could "plan" for a fertilized egg to SPLIT! I guess with fertility drugs or IVF you can "plan" that there's a "chance", but it's really up to God. But this was not our case. Totally identical means 1 egg, 1 sperm, and a spontaneous split that no one can predict, let alone plan.
Wow, I didn't realise the "did you plan on having twins" was a widely asked dumb question (How do you plan twins?). I thought I'd just

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Retrieved Text: Danielle Paull became pregnant with twins. One of the children was born prematurely, at only 24 weeks. The child weighed just 710 grams. That is only one pound and nine ounces! This was an incredibly tiny newborn. The child was immediately incubated at the Neonatal Intensive Care Unit at the Randwick Royal Hospital for Women in Sydney, Australia. Danielle was not even able to breastfeed the new baby girl, as breastfeeding could bring on contractions and the other child would be born prematurely, as well.
The other twin remains safely in utero at present, and his parents hope he can remain there for the next 16 weeks, which will make the twins four months apart in age. This is a very rare phenomenon called delayed interval delivery. This sort of delivery can be accomplished if the twins are not identical. Identical twins share a placenta, so one twin cannot survive without the other.
The premature birth procedure is attempted when a mother has a cervix that opens prematurely, which is sometimes the case with multiple fetuses.
The surgeon for this sort of birth cuts the umbilical cord very high so that it contracts back into the uterus. This keeps the delivered child’s placenta from detaching, and the body is tricked into not going into labor again to deliver the other child.
Kate Hill of Brisbane, Australia has had an even stranger experience with her twins. She and her husband Peter were attempting to conceive a child, but Kate did not become pregnant. She was diagnosed with the polycystic ovarian syndrome,

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Retrieved Text: Is Fraternal Twins More Common than Identical?
However, with identical twins, one egg actually splits in two after it is fertilized. This means that the babies will share a genotype and will have a much greater chance of looking identical than with fraternal twins. Identical twins is completely natural, and quite rare at that. You cannot seek out tips on how to have twins when it comes to identical sets.
There are many things that can increase a woman’s chances of becoming pregnant with fraternal twins. For example, some women are at a great chance because of their age and others may have twins that run in the family. These are both items that can make having twins more likely. However, there is nothing that can increase the chances of having identical twins. Even women with no history of twins in their family can have identical twins.
The number of fraternal twins continues to rise year after year. The reason for this is because of the increased age of women who are becoming pregnant. Many are also turning to fertility treatments, which can also increase the chances of becoming pregnant with twins. This increase makes it more common for fraternal twins to be born instead of identical twins.

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Retrieved Text: We always got amazed by twins because twins are captivating. They are attached to siblings and appealing as hell. Reasonably this is the reason why many women go for diets that increase their chances of having twins. The bunches of joy are their parents’ self-confidence and the wondrous things they do make us feel more enthralled by them.
Let’s Have A Look At 11 Facts About Twins That You Probably Didn’t Know Before.
Some twins usually indulge twin-talk – a language fancied by the combine that seems to be nonsense to the world however to them, it makes the best sense. As per a publication printed in the Institute of General Linguistics, twins generally use one another as guides for learning words and applying to mean to the sounds they turn out. Their special language fades away by the time they begin college.
Many believe that twins have the same fingerprints however it’s not true. they’re an equivalent in some ways as they need many resemblances with each other and even share DNA, however the one issue that’s totally different their fingerprints. Since these impressions area unit determined by DNA, nutrition and secretion levels within the female internal reproductive organ, and rate of growth, the twins have distinctive sets of lines on their digits.
It’s no secret that twins will sense once the other one is feeling worried or delight. The special connection between them transforms traditional human behaviour because the two will sometimes ‘share a brain’ and reply to a scenario in identical ways. a desirable example is that

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Retrieved Text: Twins can be fascinating as they are rare and adorable. If you have a twin brother or sister, or you have a friend who has a twin brother or sister or you are dating one of them, it is important for you to know more about twins that you have never heard of. Do you know that twins can read each other’s mind and it is not by coincidence but by design. There are many such weird things for twins that the world does not know.
Twins can develop their own language for communication which is referred to as twin talk. This language is unique and common people will not be able to make sense of it. However, this language starts to disappear as they grow old.
Twins can read each other’s mind efficiently. This means they know when the other one is happy or sad. As a matter of fact, they are likely to react to the same situation in the same way.
There is a belief that twins have same fingerprints but it is not true. There are cases where they show very close resemblence but on a micro level, there are always different. They have same DNA but not fingerprints. Fingerprints are determined by DNA, nutrition, growth rate and other factors which cannot be exactly the same for twins and hence, the fingerprint lines differ.
Most of the people think that twins are born just like that and they have no control on it. However, there are certain twin-inducing diets available for women through which they can

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Retrieved Text: Dolly, the world’s first cloned mammal and thus probably history’s most famous sheep, is likely to leave a somewhat ironic legacy. This triumph of genetic engineering, achieved last week by Scottish embryologist Ian Wilmut, might well mark the defeat of the idea that genes determine who and what we are.
A clone is an identical twin, a second creature with a genetic code identical to the first’s. Dolly, in other words, is the twin sister her original never had. Identical twins are rare in nature, and because they’re created when a single fertilized egg divides into two embryos, they’re born at the same time. If Wilmut’s techniques for cloning mammals prove to be practical, that time constraint will no longer exist. It will be possible to make twins whenever we want, to replace your old dog Pete with Puppy Pete, to replicate a deceased human infant, or to copy yourself.
But twins usually grow up in the same family and community (studies of their rearing suggest that people treat identical twins much more alike than they treat siblings or even fraternal twins). A clone’s environment will be different. It will grow from a different egg, develop in a different womb, possibly grow up in a different place, and have different triumphs and disasters.
Cloning, in other words, offers the possibility of the mother of all “twin studies”–comparisons of how often a trait appears among identical twins vs. how often it appears among others. Twin studies these days are invoked to feed the popular notion that genes determine behavior, since

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Retrieved Text: The terminology associated with a twin pregnancy can be confusing and overwhelming. Finding out that you’re having twins is just the beginning of an exciting experience; along with adjusting to the idea of having two babies at once, there is a lot to learn! Here's a guide to understanding these terms, and what they mean for the developing fetuses.
During a twin pregnancy, you may have heard the terms “Di/Di” or “Mo/Di” used to describe twins. These terms are used to classify and explain twin anatomy in the womb. Although it may sound like a lot of medical gobbledy-gook, they're important concepts for parents because some twins are at risk for complications.
These terms describe twins — always monozygotic twins — that share an environment. They are enclosed in ONE amniotic sac and/or ONE chorion.
These terms describe twins — which can be monozygotic or dizygotic — that each has their own, separate sacs. There are two placentas, although in some cases, the placentas fuse together into one.
So let’s look at them in combination.
The majority of twins are di/di, that is, dichorionic, diamniotic. That means that they developed separately, each with their own placenta and own sacs. This is how all dizygotic — or fraternal — twins develop. In addition, some monozygotic (identical) twins will also form this way, depending on how early after conception the egg splits.
However, some monozygotic twins will be mo/di or mo/mo. That means they are monochorionic but diamniotic, or they are monochorionic and monoamniotic. Twins cannot be di/mo. If there are two chorions, then

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Retrieved Text: Many aspects of human characteristics (such as height and eye color) are largely genetically determined. Psychology researchers, however, tend to be interested in dimensions that are relatively less determined by genetics—traits that subject more to environmental influences, such as how a person feels, acts, and thinks. Given that the degree of genetic determination appears to vary from one dimension to another (e.g., spatial skills versus language acquisition), how can one determine the relative influences of heredity and environment for various human characteristics, and how can one understand the complex relationship between them?
For example, Javier has two biological daughters who share the same biological mother. Both are tall, well mannered, and musically inclined. Despite these similarities, the older child appears socially reserved and quiet, while the younger one, who was born into the same family environment, seems more outgoing. In addition, one of his children has been diagnosed with a learning disability while the other seems exceptionally well-functioning cognitively. How can these similarities and differences between the two children be explained? One may think, "Well, Javier is tall and he is also a talented musician himself, so these girls must have gotten these 'good genes' from Javier. And he is quite strict when it comes to disciplining his children, so that explains their good manners. But why is the younger one so sociable—and what about her learning disability? Maybe she hasn't been read to as much as the older one has." In essence, hereditary influences and various environmental factors in these children's lives are being weighed and

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Retrieved Text: Sperm from zebrafish, Danio rerio, and Nile tilapia, Oreochromis niloticus, were microinjected directly into egg cytoplasm to evaluate the potential for developing a novel method of fertilization. In zebrafish, the sperm of two lines (wild-type and gold, long-fin) were injected with or without activation into activated and non-activated eggs. No significant difference (P = 0.997) in fertilization by intracytoplasmic sperm injection (ICSI) was observed between the two lines or when the sperm were activated or not (P = 0.057). There was significance difference in fertilization between activated and non-activated eggs (P = 0.010). The highest fertilization rate was achieved by injection of activated sperm into non-activated eggs (35%). From a total of 188 zebrafish eggs injected, 31 (16%) were fertilized, 10 (5%) developed as abnormal larvae and 3 (2%) developed normally and hatched. Damage of maternal chromosomes by the injection procedure could have caused the developmental abnormalities observed after ICSI. This was investigated by fluorescence microscopy using a DNA-specific stain (Hoechst 33324). Fixed and stained animal poles of zebrafish 30 sec after artificial insemination revealed that female chromosomes were located ~40 mm from the sperm injection site (micropyle). Staining of the animal pole after sperm injection showed no disruption of the formation of the second polar body or its extrusion. Evaluation of two sperm injection sites in zebrafish showed no difference in fertilization rate (P = 0.8264) or reduction of abnormal development. Nile tilapia eggs placed in Hanks' balanced salt solution retained their viability for at least 3 hours after collection. Of a total of 160

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Input Text: Answer the following question given this paragraph: 

(a) A jet airplane flying from Darwin, Australia, has an air speed of 260 m/s in a direction 5.0º south of west. It is in the jet stream, which is blowing at 35.0 m/s in a direction 15º south of east. What is the velocity of the airplane relative to the Earth? (b) Discuss whether your answers are consistent with your expectations for the effect of the wind on the plane’s path. (a) In what direction would the ship in Exercise 3.57 have to travel in order to have a velocity straight north relative to the Earth, assuming its speed relative to the water remains 7.00 m/s ? (b) What would its speed be relative to the Earth? 60. (a) Another airplane is flying in a jet stream that is blowing at 45.0 m/s in a direction 20º south of east (as in Exercise 3.58). Its direction of motion relative to the Earth is 45.0º south of west, while its direction of travel relative to the air is 5.00º south of west. What is the airplane’s speed relative to the air mass? (b) What is the airplane’s speed relative to the Earth? 61. A sandal is dropped from the top of a 15.0-m-high mast on a ship moving at 1.75 m/s due south. Calculate the velocity of the sandal when it hits the deck of the ship: (a) relative to the ship and (b) relative to a stationary observer on shore. (c) Discuss how the answers give a consistent result for the position at which the sandal hits the deck. The velocity of the wind relative to the water is crucial to sailboats. Suppose a sailboat is in an ocean current that has a velocity of 2.20 m/s in a direction 30.0º east of north relative to the Earth. It encounters a wind that has a velocity of 4.50 m/s in a direction of 50.0º south of west relative to the Earth. What is the velocity of the wind relative to the water? 63. The great astronomer Edwin Hubble discovered that all distant galaxies are receding from our Milky Way Galaxy with velocities proportional to their distances. It appears to an observer on the Earth that we are at the center of an expanding universe. Figure 3.64 illustrates this for five galaxies...


Q: The great astronomer edwin hubble discovered that all distant galaxies are receding from our milky way galaxy with velocities proportional to their what?

 Choices:

- distances

- paths

- masses

- dimensions

A:

Target Text: distances

#### Retrieved Documents ####

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Retrieved Text: Portion of the Hubble Ultra Deep Field. Credit: NASA, ESA, S. Beckwith (STScI) and the HUDF Team.
Redshift theory inhibits new research into the age and size of the Universe.
Two major points in Big Bang theory are that redshift is proportional to distance and that it also indicates velocity. It is assumed that the larger an object’s redshift is the farther away it is and the faster it is moving away from the observer. Those two ideas led to the commonly held belief that the Universe is expanding.
Astronomer Edwin Hubble, based on his own observations, as well as those of Vesto Slipher, believed that he had observed remote galaxies receding from the Milky Way in 1929. His greatest surprise was not the recession itself, but the apparent high velocities associated with it. It seemed as if some galaxies were moving away at thousands of kilometers per second.
Spectrograms from Hubble’s galactic images appeared to indicate a “redshift” of light frequencies. He adapted the Doppler effect (after the Austrian physicist Christian Doppler) to the spectra of various galaxies. His thought was that the change in location of “Fraunhofer lines” (for the German physicist Joseph von Fraunhofer) demonstrated a shift toward the red end of the spectrum because of galactic recessional velocity.
Fraunhofer lines occur at certain regions in the spectrum because different elements absorb unique light frequencies. If they are in a different location, then they are assumed to be Doppler-shifted from the element’s velocity. Hubble’s conclusion created the foundation for galaxy-scale distance calculations and their supposed recessional velocities. Some

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Retrieved Text: What’s the evidence that our Universe is expanding, contracting, or staying the same?
The line spectrum of hydrogen, the most common element in the Universe, has characteristic lines (wavelengths or frequencies) in the regions red, turquoise, blue, and violet. The boldest line in the hydrogen spectrum is in the red region. That is if the star or galaxy is not moving towards you or away from you. If it is moving towards you or away from you, each spectrum line will be shifted either toward the violet or toward the red end of the spectrum respectively because of the Doppler effect.
On the “Spectra of Fast-Moving Galaxies” sheet there are spectra of a number of galaxies. The darkest line indicated in each the spectrum is the one that is normally in the red region of the spectrum. With extreme Doppler shifts, that bold line can appear in radically different parts of the spectrum. The scales at the top and bottom of the sheet relate Doppler shifts of the galaxies’ spectra with velocities of the galaxies.
9.1. On the Spectra of Fast-Moving Galaxies sheet, which way are the spectra of most galaxies shifted, towards red or towards violet?
Positive velocity means the galaxy is moving away from us and negative velocity indicates the galaxy is moving towards us.
9.2. Are the galaxies moving towards us or away from us?
Find out how fast each galaxy is moving. Plot the speed on the “Hubble’s Law” worksheet to create a graph of distance vs velocity. Use a computer spreadsheet if you like.
9.3. What does the

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Retrieved Text: Ben Gilliland, is a science writer and illustrator and the 2013 winner of the Sir Arthur Clarke Award for space media. He recently published "How to Build a universe: From the Big Bang to the End of the universe" (Sterling, 2015). Gilliland contributed this excerpt to Space.com's Expert Voices: Op-Ed & Insights.
The cover of "How to Build a Universe: From the Big Bang to the End of the Universe."
The notion that the universe was born in a "Big Bang," or indeed anything else, is a relatively new concept. In fact, even the term Big Bang was coined by someone who didn't believe in it and intended it as a disparaging putdown. Today, however, Big Bang theory is one of the most successful ideas in science, but how did we get there?
Science moved on a bit by the 16th and 17th centuries, with the likes of the astronomer Nicolaus Copernicus and the famous Italian polymath Galileo Galilei, who used reasoning, mathematics, and observation to prove that the Earth and the rest of the planets orbit the sun.
A crucial innovation at that time was the invention of the telescope. Originally little more than an amusing curiosity, the telescope was introduced to astronomy in 1609 by Galileo Galilei and the not-so famous English polymath, Thomas Harriot (who used his telescope to sketch the Moon four months before Galileo's celebrated observations, and who is sometimes credited with introducing the potato to England).
The telescope helped increase the size at which we could view the universe. Galileo's observations of the strange milky

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Retrieved Text: Let’s start with an explanation of how astronomers know that the universe is expanding. The concepts we need to look at are velocities – not accelerations – of distant galaxies.
Beginning in the 1920s, Edwin Hubble used the 100 inch telescope on Mount Wilson to measure the distances to galaxies using Cepheid variable stars as distance indicators. Hubble also studied the spectra of galaxies and found that all but the nearest galaxies had a Doppler redshift in their spectra. Doppler redshifts tell us that an astronomical object is moving away from us. Larger redshifts indicate larger recessional velocities, or objects that are moving away faster.
When Hubble graphed the recessional velocities of galaxies versus their distances, he found a linear relationship. The more distant galaxies appeared to be moving away from us more rapidly. Astronomers call this graph the Hubble plot or Hubble’s law.
Hubble then deduced the reason for this effect: The universe is expanding. The slope of the Hubble plot, called the Hubble constant, tells astronomers how fast the universe is expanding and allows astronomers to calculate the age of the universe in the context of the big bang model. Astronomers also use Hubble’s law to calculate the distances to very distant galaxies from their measured redshifts.
To visualize why Hubble’s law tells astronomers the universe is expanding, draw a bunch of dots on a balloon. Then watch the dots while blowing up the balloon. From the vantage point of any given dot all the other dots will appear to be moving away with the more distant dots

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Retrieved Text: Not long ago, there were no galaxies far, far away. In fact, less than a century ago, many scientists believed there was just one galaxy, the Milky Way. All that changed, however, on December 30th, 1924, when American astronomer Edwin Hubble announced he had evidence that the Milky Way galaxy was just one of the many galaxies in an ever expanding universe.
To commemorate his discovery, here are 7 facts about the man who changed our universe forever.
In the 1920s, Edwin Hubble made history by looking through a 100-inch telescope at Mount Wilson in Southern California. Training his gaze on the Andromeda Nebula, he saw stars similar to ones in our galaxy, only dimmer. One of those stars was a Cepheid variable, which astronomers could use to measure distances. The discovery of the Cepheid variable allowed Hubble to deduce that the Andromeda Nebula was not a nearby cluster of stars, but an entirely different galaxy. By the 1930s, most astronomers had been convinced that the Milky Way galaxy was but one of millions in the universe. The very notion that there was more than one galaxy in the universe was revolutionary and earned Hubble the title as the greatest astronomer since Galileo.
2. He helped Albert Einstein.
Discovering that our galaxy wasn’t alone was just the beginning for Hubble. He continued measuring distances and velocities in deep space, finding that the further apart galaxies are from each other, the faster they move away from one another. His findings, published in 1929, led to the widely accepted notion that the

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Retrieved Text: The American astronomer Edwin Powell Hubble (1889-1953) established the scale of the universe and laid the observational basis for the cosmological theory of the expanding universe.
Edwin Hubble was born on Nov. 20, 1889, in Marshfield, Mo., where his father, a lawyer, was in the insurance business. Hubble received scholarship aid to go to the University of Chicago. He chose law for a career, and after receiving his bachelor's degree in 1910, he went as a Rhodes scholar to Oxford University, England. In 1913 he returned to the United States, was admitted to the bar in Kentucky, and practiced law for about a year in Louisville.
Quite suddenly, Hubble decided that he would devote his life to astronomy, and in 1914 he left for the University of Chicago's Yerkes Observatory in Williams Bay, Wis. In 1917 he completed his doctorate and enlisted in the infantry. He served in France as a line officer in the American Expeditionary Force.
As a student at Chicago, Hubble had attracted the attention of the well-known astronomer G. E. Hale, and after the war Hale offered him a staff position at Mount Wilson Observatory near Pasadena, Calif. Except for the period 1942-1946, when Hubble was with the Ordnance Department in Aberdeen, Md., he was connected with the Mount Wilson Observatory for the rest of his life.
Hubble's early observations at Mount Wilson were made with its 60-inch reflecting telescope and concentrated on objects within our own galaxy, for example, novae, nebulous stars, and variable stars. Gradually he began to observe more distant objects. To determine

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Retrieved Text: nature of some of the spiral nebulae.
systems of stars remote from our own Milky Way.
of thousands compared to the size of the Milky Way.
later the Palomar 200-inch, he observed a striking correlation.
The more distant a galaxy was, the faster it was moving away from us.
had a red shift not a blue shift, meaning it was receding rather than approaching.
In this situation, a linear relationship between red shift and distance.
We can invert the logic and imagine a time when all galaxies were closer together.
Hubble law points to an origin for the universe, tracing time backwards.
named after Edwin Hubble, and the current expansion rate of the universe.
The steeper this relationship, the faster the current expansion rate.
The shallower this relationship, the slower the current expansion rate.
measured to be roughly 72 kilometers per second per megaparsec.
the recession velocity increases by about 70 kilometers per second.
we understand Hubble's observations now in terms of expanding space.
Hubble spoke simply about recession velocities.
in and causes every galaxy to move away from every other galaxy.
where the fabric of the balloon is space time itself.
Objects on the surface of the balloon are carried away from one another.
The best analogy would be tiny beads glued to the surface of the balloon.
Since galaxies individually are held together by their own gravity.
the galaxies themselves do not grow in size.
What does the linear expansion imply?
that we're the center of the universe?
the red galaxy, measuring the distances and speeds of galaxies near us.
The green and the blue.
We can see that the more distant galaxies move away faster.
That's the linear relationship Hubble

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Retrieved Text: Imagine finding a living dinosaur in your backyard. Astronomers have found the astronomical equivalent of prehistoric life in our intergalactic backyard: a group of small, ancient galaxies that has waited 10 billion years to come together. These "late bloomers" are on their way to building a large elliptical galaxy.
Such encounters between dwarf galaxies are normally seen billions of light-years away and therefore occurred billions of years ago. But these galaxies, members of Hickson Compact Group 31, are relatively nearby, only 166 million light-years away.
New images of this foursome by NASA's Hubble Space Telescope offer a window into the universe's formative years when the buildup of large galaxies from smaller building blocks was common.
Astronomers have known for decades that these dwarf galaxies are gravitationally tugging on each other. Their classical spiral shapes have been stretched like taffy, pulling out long streamers of gas and dust. The brightest object in the Hubble image is actually two colliding galaxies. The entire system is aglow with a firestorm of star birth, triggered when hydrogen gas is compressed by the close encounters between the galaxies, and collapses to form stars.
The Hubble observations have added important clues to the story of this interacting group, allowing astronomers to determine when the encounter began and to predict a future merger.
"We found the oldest stars in a few ancient globular star clusters that date back to about 10 billion years ago. Therefore, we know the system has been around for a while," says astronomer Sarah Gallagher of The University of Western Ontario in London, Ontario,

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Retrieved Text: How big is the Universe? How old is it?
Today, cosmology is dominated by the Big Bang theory. The theory’s major premise is that there was once a void containing no matter, no space, and no time. For some reason not explained by the scientists who support the theory, an irruption of energy from another realm of existence replaced the void with what eventually became the present Universe.
The Big Bang theory was postulated because the astronomer Edwin Hubble, using the 100-inch telescope at Mt. Wilson observatory, believed that he had observed remote galaxies receding from the Milky Way. The most surprising piece of his recorded data was not the recession itself, but the high velocities associated with his measurements. According to his calculations, some galaxies were traveling away from his observatory at thousands of kilometers per second.
Hubble arrived at his conclusion because of what was later to be called the “redshift” of light frequencies in spectrograms from his galactic images. Adapting the Doppler effect (named for the Austrian physicist Christian Doppler, who came up with the idea in 1842) to the spectra of various galaxies, Hubble thought that the change in location of particular elemental signatures called Fraunhofer lines (for the German physicist Joseph von Fraunhofer) indicated that the lightwaves had been shifted toward the red end of the spectrum by an apparent recessional velocity.
Fraunhofer lines are supposed to occur at specific frequencies identified in the spectrum by the kind of element that is absorbing the light. If they are in a different location, then they have

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Retrieved Text: The Hubble Space Telescope (HST) is one of NASA ‘Great Observatories’ located in low Earth orbit. During its years of service, Hubble has made priceless discoveries in the field of astronomy while also ‘pulling back the curtain’ to reveal the true beauty of universe through countless stunning images. Hubble was launched by the Space Shuttle Discovery in 1990 for a planned mission of 5 years.
Hubble Space Telescope Fast Summary Facts!
Until the year 1610, all that man knew about the night skies was what w could see with the naked eye. With the invention of the telescope came a revolution in astronomy. Our place in the cosmos would be forever changed as discoveries revealed the true nature of the Solar System, Milky Way Galaxy and universe beyond.
On Earth, telescopes would progressively get larger and larger. They would be located far from city lights, on mountain tops high above the atmosphere’s cloud. However, the ultimate location for a telescope is in space where it is free of the distorting effects of the Earth’s atmosphere.
The Hubble Space Telescope was the first major telescope to be placed in space. Here Hubble conducts scientific observations and images distant faint objects in unprecedented detail. It would reveal objects of unimaginable beauty and increase our understanding of the Milky Way Galaxy, and the universe, more than any other instrument in history!
Since Hubble's launch in April 1990, there have been five further visits by Space Shuttle crews to service and upgrade one of NASA’s great observatories (along with the Chandra X-ray Observatory, the Spitzer

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Retrieved Text: A spiral galaxy that is usually shrouded behind our own Milky Way has come out of hiding in a new infrared image from NASA's latest space telescope.
The new photo reveals a leggy cosmic apparition called IC 342, sometimes known as the "hidden galaxy," and was snapped by the Wide-field Infrared Survey Explorer (WISE). The WISE space telescope is mapping the sky in unprecedented detail to find previously unseen asteroids and other objects.
Stargazers and professional astronomers typically have a difficult time seeing this galaxy through the Milky Way's bright band of stars, dust and gas, but WISE's infrared vision penetrates through this veil, offering a crisp view.
In a spiral galaxy like IC 342, dust and gas are concentrated in the arms. The denser pockets of gas trigger the formation of new stars, which is represented in green and yellow in the photo.
The core, shown in red, is also bursting with young stars, which are heating up dust. Stars that appear blue reside within our Milky Way, between us and IC 342.
This galaxy has been of great interest to astronomers because of its relative proximity to our planet. Yet, determining its exact distance from Earth has proven difficult due to the intervening Milky Way.
The famed late astronomer Edwin Hubble, after whom the Hubble Space Telescope is named, first thought the galaxy might belong to our own Local Group, a neighborhood of about 40 galaxies that includes the Milky Way and Andromeda. But current estimates now place it farther away, at about 6.6 to 11 million light-years.

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Retrieved Text: Our home in space is a vast galaxy containing 400 billion suns, at least that many planets, and a 4-billion-solar-mass black hole at the center.
Our Milky Way is a barred spiral galaxy containing 400 billion stars bound together by gravity. From Earth, the galaxy has the appearance of a faintly luminous band in the sky.
The naked eye cannot resolve the individual stars making up the band, and it was not until the invention of the telescope in the 17th century that it was proved that the Milky Way galaxy contained multitudes of stars.
In the early decades of the 20th century, astronomer Edwin Hubble photographed other galaxies and determined that they too are huge systems of many stars, and not just small structures within our own galaxy. The Milky Way is but one among multitudes of galaxies in space.
The spiral structure of the Milky Way is obscured by the fact that our Earth, sun and nearby planets are embedded in the galaxy’s disc. Observation of the shapes of other galaxies led to the realization that ours might be a spiral type.
Today, new techniques for measuring distance n deep space are helping astronomers put together a picture of the true shape of our Milky Way galaxy, although much debate remains about details such as the exact shape and location of the spiral arms and central bar.

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Retrieved Text: During his work studying galaxies, Hubble used Cepheid variable stars to measure the distances to a sample of galaxies. Even before the Shapley/Curtis debate and the discovery that spiral nebulae are external galaxies, observations had shown that the vast majority of galaxies had spectral lines redshifted from the laboratory values. If you recall from our work on the Doppler effect, a redshift in a spectral line indicates that the object is moving away from us. In a publication by Hubble in 1929, he showed that if you plot the distance to a galaxy (measured from Cepheid variables) and the velocity of the galaxy (measured by the shift in the spectral lines), the two quantities are directly correlated! See the reproduction of his plot below.
Read Hubble's original articles! The astronomical community maintains an excellent resource meant primarily for practicing astronomers. It is the SAO/NASA Astrophysics Data System, and you can use it to search the astronomical literature. For example, if you want to find information on every article I have ever published, you can go there and stick my name in the author field. However, for a much more interesting search, you can go there and put in "Hubble, E" in the author field, and it will bring up the listing of Hubble's published works, including the paper in which he published the plot above.
Hubble's law, which says simply that a galaxy's velocity (or as is sometimes plotted, its redshift) is directly proportional to its distance, also tells us something important about the state of the universe.

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Retrieved Text: For the first time, two astronomers have explained the diversity of galaxy shapes seen in the universe. The scientists, Dr Andrew Benson of the California Institute of Technology (Caltech) and Dr Nick Devereux of Embry-Riddle University in Arizona, tracked the evolution of galaxies over thirteen billion years from the early Universe to the present day. Their results appear in the journal Monthly Notices of the Royal Astronomical Society.
Galaxies are the collections of stars, planets, gas and dust that make up most of the visible component of the cosmos. The smallest have a few million and the largest as many as a million million (a trillion) stars.
American astronomer Edwin Hubble first developed a taxonomy for galaxies in the 1930s that has since become known as the ‘Hubble Sequence’. There are three basic shapes: spiral, where arms of material wind out in a disk from a small central bulge, barred spirals, where the arms wind out in a disk from a larger bar of material and elliptical, where the galaxy’s stars are distributed more evenly in a bulge without arms or disk. For comparison, the galaxy we live in, the Milky Way, has between two and four hundred thousand million stars and is classified as a barred spiral.
Explaining the Hubble Sequence is complex. The different types clearly result from different evolutionary paths but until now a detailed explanation has eluded scientists.
Benson and Devereux combined data from the infrared Two Micron All Sky Survey (2MASS) with their sophisticated GALFORM computer model to reproduce the evolutionary history of the Universe

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Retrieved Text: The composite image at left, taken in visible and near-infrared light, reveals the location of five tiny galaxies clustered together 13.1 billion light-years away. The circles pinpoint the galaxies.
Astronomers have discovered the most distant developing galaxy cluster known to date, shedding light on the formation of large-scale structure in the early universe, a new study reports.
Researchers used NASA's Hubble Space Telescope to find five tiny but bright galaxies clustered together 13.1 billion light-years from Earth. That means Hubble is observing them as they existed just 600 million years after the Big Bang, the dramatic event that brought our universe into existence.
"These galaxies formed during the earliest stages of galaxy assembly, when galaxies had just started to cluster together," Michele Trenti, of the University of Colorado at Boulder and the University of Cambridge in the United Kingdom, said in a statement. "The result confirms our theoretical understanding of the buildup of galaxy clusters. And, Hubble is just powerful enough to find the first examples of them at this distance."
The study will also be published in an upcoming issue of The Astrophysical Journal.
Hubble spotted the five galaxies while performing a random sky survey in near-infrared light.
The newfound galaxies are small, ranging from 10 percent to 50 percent the size of our own Milky Way. But they're about as bright as the Milky Way, because they're feasting on huge amounts of gas via mergers with other galaxies, researchers said.
Most galaxies reside in clusters or groups. Galaxy clusters are the largest structures in the universe, comprising hundreds or thousands of

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Retrieved Text: Historically, famous astronomers and their contributions have paved the way for new theories. For over 10,000 years, astronomical writings, philosophies, beliefs and theories have been found in every corner of the world. It is amazing how certain beliefs began in one area of the world, only to be proven (or disproved) many years (sometimes over 1,000 years) later.
The 20th Century delivered many more famous astronomers with new ideas, theories and revelations. The latest astronomers and their contributions led to even more knowledge of the Milky Way and other galaxies never before known to have existed.
Born in Marshfield, Missouri, USA, Edwin Hubble is most famous for his discoveries of other galaxies beyond the Milky Way. His research into these other galaxies made way for his theory that galaxies are constantly moving away from each other. He believed that the further away a galaxy was from another, the faster they actually continue to move away from each other. Edwin Hubble discovered that the Andromeda Galaxy (formerly named the Andromeda Nebula) was indeed its own galaxy and not simply an astronomical spiral, as previously believed. Edwin eventually created the Hubble sequence to classify each galaxy.
Bulgarian astronomer Fritz Zwicky is most noted for introducing the term “super-nova”. He found that some novae were more than an unstable star with surface outbursts; super-nova being the explosion of an entire star. Fritz Zwicky created the ideas that massive stars end their own lives in huge explosions which produce cosmic rays and leave the star collapsed. In his lifetime, Fritz Zwicky discovered 122

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Retrieved Text: The following is a list of notable galaxies.
There are about 50 galaxies in our Local Group (see list of nearest galaxies for a complete list), on the order of 100,000 in our Local Super-cluster and an estimated number of about 170 billion in all of the observable universe.
The discovery of the nature of galaxies as distinct from other nebulae (interstellar clouds) was made in the 1920s. The first attempts at systematic catalogues of galaxies were made in the 1960 the Catalogue of Galaxies and Clusters of Galaxies listing 29,418 galaxies and galaxy clusters, and with the Morphological Catalogue of Galaxies, a putatively complete list of galaxies with photographic magnitude above 15 comprising 30,642 items. In the 1980s, the Lyons Groups of Galaxies listed 485 galaxy groups with 3,933 member galaxies. Galaxy Zoo is a project aiming at a more comprehensive list; launched in 2007 it catalogued some 50 million galaxies by 2011 (some 0.03% of the estimated total).
This is a list of galaxies that are well known by something other than an entry in a catalog or list, or a set of coordinates, or a systematic designation.
Milky Way Sagittarius(centre) This is the galaxy that contains Earth, it is named after the nebulosity in the night sky that marks the densest concentration of stars of our galaxy in the sky, which appears to blur together into a faint glow, called the Milky Way.
Andromeda Andromeda Commonly just Andromeda, this, called the Andromeda Galaxy, Andromeda Nebula, Great Andromeda Nebula, Andromeda Spiral Nebula, and such, has been traditionally called Andromeda,

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Retrieved Text: A riot of colour and light dances through this peculiarly shaped galaxy, NGC 5256. Its smoke-like plumes are flung out in all directions and the bright core illuminates the chaotic regions of gas and dust swirling through the galaxy's centre. Its odd structure is due to the fact that this is not one galaxy, but two—in the process of a galactic collision.
NGC 5256, also known as Markarian 266, is about 350 million light-years away from Earth, in the constellation of Ursa Major (The Great Bear). It is composed of two disc galaxies whose nuclei are currently just 13 000 light-years apart. Their constituent gas, dust, and stars are swirling together in a vigorous cosmic blender, igniting newborn stars in bright star formation regions across the galaxy.
Interacting galaxies can be found throughout the Universe, producing a variety of intricate structures. Some are quiet, with one galaxy nonchalantly absorbing another. Others are violent and chaotic, switching on quasars, detonating supernovae, and triggering bursts of star formation.
While these interactions are destructive on a galactic scale, stars very rarely collide with each other in this process because the distances between them are so vast. But as the galaxies entangle themselves, strong tidal effects produce new structures—like the chaotic-looking plumes of NGC 5256—before settling into a stable arrangement after millions of years.
In addition to the bright and chaotic features, each merging galaxy of NGC 5256 contains an active galactic nucleus, where gas and other debris are fed into a hungry supermassive black hole. Observations from NASA's Chandra X-ray Observatory show that

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Retrieved Text: The Milky Way is the galaxy that contains our Solar System. This name derives from its appearance as a dim “milky” glowing band arching across the night sky, in which the naked eye cannot distinguish individual stars. The term “Milky Way” is a translation of the Classical Latin via lactea, from the Hellenistic Greek (pr. galaxías kýklos, “milky circle”). The Milky Way appears like a band because it is a disk-shaped structure being viewed from inside. The fact that this faint band of light is made up of stars was proven in 1610 when Galileo Galilee used his telescope to resolve it into individual stars. In the 1920′s, observations by astronomer Edwin Hubble showed that the Milky Way is just one of many galaxies.
The Milky Way is a barred spiral galaxy 100,000–120,000 light-years in diameter containing 200–400 billion stars. It may contain at least as many planets. Our Solar System is located within the disk, around two thirds of the way out from the Galactic Center, on the inner edge of a spiral-shaped concentration of gas and dust called the Orion–Cygnus Arm. The stars in the inner 10,000 light-years are organized in a bulge and one or more bars. The very center is marked by an intense radio source named Sagittarius A* which is likely to be a super-massive black hole. The Galaxy rotates deferentially, faster towards the center and slower towards the outer edge. The rotational period is about 200 million years at the position of the Sun. The Galaxy as a whole is moving

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Retrieved Text: We have a lot of crazy informal names for space sights. Sometimes they’re named after how they are shaped, like the Horsehead Nebula. Sometimes they have a name “borrowed” from their constellation, such as the Andromeda Galaxy. But what about our own galaxy, the Milky Way? Why does this band of stars across Earth’s sky have a name associated with food?
First, let’s back up a bit and talk a bit about what the Milky Way actually is. Astronomers believe it is a barred spiral galaxy — a galaxy with a spiral shape that has a line of stars across its middle, as you can see in the picture above. If you were to fly across the galaxy at the speed of light, it would take you an astounding 100,000 years.
The Milky Way is part of a collection of galaxies called the Local Group. We’re on a collision course with the most massive and largest member of that collection, which is the Andromeda Galaxy (also known as M31). The Milky Way is the second-largest galaxy, and the Triangulum Galaxy (M33) the third-largest. There are roughly 30 members of this group all told.
To get a sense of its immense size, you’ll be glad to hear the Earth is nowhere near the Milky Way’s center and its powerful, supermassive black hole. NASA says we’re roughly 165 quadrillion miles from the black hole, which is found in the direction of the constellation Sagittarius.
The magnetic field of our Milky Way Galaxy as seen by ESA’s Planck satellite. Credit: ESA and the

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Retrieved Text: Astronomers have come up with one of the most accurate measurements of the galaxy's mass yet — and as it turns out, it's "on the beefier side".
Using NASA's Hubble Space Telescope and the European Space Agency's Gaia satellite, a team of international scientists determined the Milky Way (the galaxy that contains our solar system) weighs in at about 1.5 trillion solar masses.
For those playing along at home, that's about 1.5 trillion times the weight of the Earth's Sun.
The findings are an important breakthrough for astronomers, who had been relying on earlier research dating back several decades that estimated the galaxy's mass as somewhere between 500 billion to 3 trillion solar masses.
"We want to know the mass of the Milky Way more accurately so that we can put it into a cosmological context and compare it to simulations of galaxies in the evolving universe," Roeland van der Marel of the Space Telescope Science Institute (STScI) wrote in a blog post for NASA.
"Not knowing the precise mass of the Milky Way presents a problem for a lot of cosmological questions."
Interestingly, astronomers determined that only a tiny percentage of the galaxy's mass could be attributed to the approximately 200 billion stars in the Milky Way.
Rather, most of its mass is locked up in dark matter, an invisible substance that, according to the space administration, "acts like scaffolding throughout the universe and keeps the stars in their galaxies".
Ancient rocks tell us plenty about Earth's history, and may hold hints of billion-year-old cosmic encounters with dark matter.
"We just can't detect dark

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Retrieved Text: NASA's Hubble Space Telescope has uncovered a cluster of galaxies in the initial stages of construction – the most distant such grouping ever observed in the early universe.
In a random sky survey made in near-infrared light, Hubble spied five tiny galaxies clustered together 13.1 billion light-years away. They are among the brightest galaxies at that epoch and very young, existing just 600 million years after the universe's birth in the big bang.
Galaxy clusters are the largest structures in the universe, comprising hundreds to thousands of galaxies bound together by gravity. The developing cluster, or protocluster, seen as it looked 13 billion years ago, presumably has grown into one of today's massive "galactic cities", comparable to the nearby Virgo cluster of more than 2,000 galaxies.
Most galaxies in the universe reside in groups and clusters, and astronomers have probed many mature galactic cities in detail as far as 11 billion light-years away. But finding clusters in the early phases of construction has been challenging because they are rare, dim, and widely scattered across the sky.
"We need to look in many different areas because the odds of finding something this rare are very small," said Trenti, who used Hubble's sharp-eyed Wide Field Camera 3 (WFC3) to pinpoint the cluster galaxies. "It's like playing a game of Battleship: the search is hit and miss. Typically, a region has nothing, but if we hit the right spot, we can find multiple galaxies."
Because distant, fledgling clusters are so dim, the team hunted for the systems' brightest galaxies. These brilliant light bulbs act

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Retrieved Text: Thursday, March 3rd, was a historic day for NASA as well as all humanity. Astronomers reported the discovery of a galaxy that formed just 400 million years after the Big Bang explosion. The newfound galaxy, named GN-z11, is the most distant galaxy found to date.
On the matter, Yale astronomer Pascal Oesch stated: “We’ve taken a major step back in time, beyond what we’d ever expected to be able to do with Hubble”.
GN-z11 was actually first spotted two years ago during Hubble Space Telescope deep-sky visible light survey. At the time, astronomers believed they were seeing something, possibly as distant as 13.2 billion light-years from Earth. And they were right in their assumption, only further observation using a specific instrument located on Hubble, which splits light into its component wavelengths, revealed that the galaxy was located even farther than they had estimated.
According to NASA, Hubble’s most recently discovery is now confirmedly located about 13.4 billion light-years from Earth, in the direction of the constellation Ursa Major. It reportedly contains about 1 billion times the mass of the sun and it is about 25 times smaller in size than the Milky Way.
“We’re seeing this galaxy in its infancy. It’s amazing that a galaxy so massive existed only 200 million to 300 million years after the very first stars started to form. It takes really fast growth, producing stars at a huge rate, to have formed a galaxy that is a billion solar masses so soon,”, said astronomer Garth Illingworth from the University of California.
NASA reports that this discovery

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Retrieved Text: Astronomers say some of the galaxy’s most distant stars were actually whisked away from a passing mini-galaxy.
The force of gravity can be described using a number of metaphors: It’s the glue that holds solar systems and galaxies together, the anchor that keeps us on the ground, the slingshot that sends spacecraft deeper into the solar system.
And in some cases, gravity is a thief.
Astronomers at the Harvard-Smithsonian Center for Astrophysics said Wednesday they have discovered that some of the most distant stars in the Milky Way galaxy actually came the Sagittarius dwarf galaxy, one of the dozens of smaller galaxies surrounding ours. When Sagittarius passed by, the Milky Way’s gravitational tides pulled on the galaxy, and made off with five stars.
The five interlopers are among the farthest known stars in the Milky Way, located in a stretch of stars outside the galaxy’s spiral disk. Astronomers determined their origin using computer simulations. They simulated the movements of the Sagittarius and Milky Way galaxies over the course of 8 billion years. The test showed that over time, Sagittarius lost about one-third of its stars. The stars, the scientists say, were whisked away by the Milky Way and settled into streams at the galaxy’s edge. The observed position and velocities of the stolen stars also suggests they came from Sagittarius, they say.
This kind of cosmic theft may be common in the universe, particularly in neighborhoods of closely orbiting galaxies. In 2011, scientists using a ground-based telescope in Chile to study the Large Magellanic Cloud, another satellite galaxy of the Milky

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Retrieved Text: To a distant observer, our own Milky Way and the Andromeda galaxy would probably look very similar. Although Andromeda is longer, more massive, and more luminous than the Milky Way, both galaxies are vast spirals composed of hundreds of millions of stars. But new research presented at this week’s AAS conference in Seattle suggests that there are other differences as well – namely, in the movement and behavior of certain stellar age groups. This observation is the first of its kind, and raises new questions about the factors that contribute to the formation of spiral galaxies like our own.
Armed with data from both the Hubble Space Telescope and the Keck Observatory in Hawaii, a group of astronomers from UC Santa Cruz resolved 10,000 tiny points of light in the Andromeda galaxy into individual stars and used their spectra to calculate the stars’ ages and velocities – a feat never before accomplished for a galaxy outside of our own.
Led by Puragra Guhathakurta, a professor of astrophysics, and Claire Dorman, a graduate student, the researchers found that in Andromeda, the behavior of older stars is surprisingly more frazzled than that of their younger counterparts; that is, they have a much wider range of velocities around the galactic center. Meanwhile, in the Milky Way, stars of all ages seem to coexist far more peacefully, moving along at the same speed in a consistent, ordered pack.
The astronomers believe that this asymmetry causes Andromeda to look more distinct from our own galaxy than previously thought. “If you could look at [Andromeda’s]

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Retrieved Text: 1. What is a galaxy?
A galaxy is an enormous collection of a few million to trillions of stars, gas, and dust held together by gravity. Galaxies can be several thousand to hundreds of thousands of light-years across.
2. What is the name of our galaxy?
The name of our galaxy is the Milky Way. All of the stars that you see at night and our Sun belong to the Milky Way. When you go outside in the country on a dark night and look up, you will see a milky, misty-looking band stretching across the sky. When you look at this band, you are looking into the densest parts of the Milky Way: the disk and the bulge.
3. Where is Earth in the Milky Way galaxy?
Our solar system is in a spiral arm called the Orion Arm, and is about two-thirds of the way from the center of our galaxy to the edge of the starlight. Earth is the third planet from the Sun in our solar system of nine planets.
4. What is the closest galaxy like our own, and how far away is it?
The closest spiral galaxy is Andromeda, a galaxy much like our own Milky Way. It is 2.2 million light-years away from us. Andromeda is approaching our galaxy at a rate of 670,000 miles per hour. Five billion years from now it may even collide with our Milky Way galaxy.
5. Why do we study galaxies?
By studying other galaxies, astronomers learn more about the Milky Way, the galaxy that contains our solar system. Answers to such

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Retrieved Text: The Hubble Space Telescope has made an unexpected discovery of a dwarf galaxy in our cosmic backyard, located just 30 million light-years away, scientists say.
Researchers used the NASA/ESA Hubble Space Telescope to study white dwarf stars within the globular cluster NGC 6752.
In the outer fringes of the area observed with Hubble's Advanced Camera for Surveys a compact collection of stars was visible, according to a study published in the journal Monthly Notices of the Royal Astronomical Society: Letters.
After a careful analysis of their brightnesses and temperatures, the astronomers concluded that these stars did not belong to the cluster -- which is part of the Milky Way -- but rather they are millions of light-years more distant.
The cosmic neighbour, nicknamed Bedin 1, is a modestly sized, elongated galaxy. It measures only around 3000 light-years at its greatest extent -- a fraction of the size of the Milky Way.
Not only is it tiny, but it is also incredibly faint, researchers said. These properties led astronomers to classify it as a dwarf spheroidal galaxy.
Dwarf spheroidal galaxies are defined by their small size, low-luminosity, lack of dust and old stellar populations. 36 galaxies of this type are already known to exist in the Local Group of Galaxies, 22 of which are satellite galaxies of the Milky Way.
While dwarf spheroidal galaxies are not uncommon, Bedin 1 has some notable features. Not only is it one of just a few dwarf spheroidals that have a well established distance but it is also extremely isolated.
It lies about 30 million light-years from the Milky

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Retrieved Text: Our galaxy, the Milky Way, is more than just a giant spiral harboring hundreds of billions of stars. It&apos;s also the hub of a gargantuan empire that stretches over more than a million light-years and rules some two dozen lesser galaxies, which revolve around it the way moons orbit a giant planet.
Of all our galaxy&apos;s many satellites, none compares to the Magellanic Clouds—a pair of bold and beautiful galaxies far more lively and lustrous than any other in the Milky Way&apos;s retinue. Visible in the southern sky as fragments of glowing mist, this galactic duo poses something of a mystery to astronomers. The Milky Way&apos;s gravity has robbed all its other satellites of the gas they need to make stars, so how have the Large and Small Magellanic Clouds remained so bright and bountiful, filled with brilliant young stars and the gas and dust that create them?
Evidence is mounting that the Magellanic Clouds are so healthy because until recently they have avoided the Milky Way and its gas-grabbing tactics. Seven years ago Nitya Kallivayalil, an astronomer now at Yale University, and her colleagues reported Hubble Space Telescope observations showing that their orbit was much more enormous than previously thought. Prior to Kallivayalil&apos;s work, astronomers thought the Magellanic Clouds orbited our galaxy every one or two billion years. Now it seems they require at least four billion years to fully revolve around it—and possibly much longer. Her latest Hubble data, published in February, yield a more precise path for the pair and strengthen her initial discovery, suggesting

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Retrieved Text: Until now, the biggest supermassive black holes -- those having more than 10 billion times the mass of our Sun -- have only been found at the cores of very large galaxies in the centres of massive galaxy clusters. Now, an international team of astronomers using the NASA/ESA Hubble Space Telescope has discovered a supersized black hole with a mass of 17 billion Suns in the centre of the rather isolated galaxy NGC 1600.
NGC 1600 is an elliptical galaxy which is located not in a cluster of galaxies, but in a small group of about twenty. The group is located 200 million light-years away in the constellation Eridanus (constellation). While finding a gigantic supermassive black hole in a massive galaxy within a cluster of galaxies is to be expected, finding one in an average-sized galaxy group like the one surrounding NGC 1600 is much more surprising.
"Even though we already had hints that the galaxy might host an extreme object in the centre, we were surprised that the black hole in NGC 1600 is ten times more massive than predicted by the mass of the galaxy," explains lead author of the study Jens Thomas from the Max Planck-Institute for Extraterrestrial Physics, Germany.
Based on previous Hubble surveys of supermassive black holes, astronomers had discovered a correlation between a black hole's mass and the mass of its host galaxy's central bulge of stars: the larger the galaxy bulge, the more massive the black hole is expected to be. "It appears from our finding that this relation does not work

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Retrieved Text: A Hubble Space Telescope image of the typical globular cluster Messier 80, an object made up of hundreds of thousands of stars and located in the direction of the constellation of Scorpius. The Milky Way galaxy has an estimated 160 globular clusters of which one quarter are thought to be 'alien'.
Manyof our galaxy?s star clusters may actually foreigners: collections of starsthat were born elsewhere and then migrated to our Milky Way, according to a newstudy.
Theforeign-born starclusters actually make up about one-quarter of the Milky Way globular starcluster system, researchers found.
"Itturns out that many of the stars and globular star clusters we see when we lookinto the night sky are not natives, but aliens from other galaxies,"said study co-author Duncan Forbes, an astronomer from Swinburne University ofTechnology in Australia. "They have made their way into our galaxy overthe last few billion years."
Astronomerspreviously suspected that some globular star clusters, which each containbetween 10,000 and several million stars, were foreign to our galaxy, but itwas difficult to positively identify which ones.
Tofind them, Forbes, along with his colleague Terry Bridges of Queens Universityin Ontario, Canada, used data from the Hubble Space Telescope to examineglobular star clusters within the Milky Way galaxy.
Theythen compiled the largest ever high-quality database to record the age andchemical properties of each of these clusters.
"Usingthis database we were able to identify key signatures in many of the globularstar clusters that gave us tell-tale clues as to their external origin,"Forbes said.
Theresearch will be detailed in an upcoming edition of Monthly Notices of theRoyal Astronomical Society.
Thework also suggests that

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Input Text: Answer the following question given this paragraph: 

Valence bond theory describes the benzene molecule and other planar aromatic hydrocarbon molecules as hexagonal rings of sp2-hybridized carbon atoms with the unhybridized p orbital of each carbon atom perpendicular to the plane of the ring. Three valence electrons in the sp2 hybrid orbitals of each carbon atom and the valence electron of each hydrogen atom form the framework of σ bonds in the benzene molecule. The fourth valence electron of each carbon atom is shared with an adjacent carbon atom in their unhybridized p orbitals to yield the π bonds. Benzene does not, however, exhibit the characteristics typical of an alkene. Each of the six bonds between its carbon atoms is equivalent and exhibits properties that are intermediate between those of a C–C single bond and a C = C double bond. To represent this unique bonding, structural formulas for benzene and its derivatives are typically drawn with single bonds between the carbon atoms and a circle within the ring as shown in Figure 20.11.


Q: Which theory describes the benzene molecule and other planar aromatic hydrocarbon molecules as hexagonal rings of sp2-hybridized carbon atoms with the unhybridized p orbital of each carbon atom perpendicular to the plane of the ring?

 Choices:

- covalent bond theory

- molecular orbital theory

- hybrid orbital theory

- valence bond theory

A:

Target Text: valence bond theory

#### Retrieved Documents ####

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Retrieved Text: The largest database1 of organic compounds lists about 10 million substances, which include compounds originating from living organisms and those synthesized by chemists. The number of potential organic compounds has been estimated2 at 1060—an astronomically high number. The existence of so many organic molecules is a consequence of the ability of carbon atoms to form up to four strong bonds to other carbon atoms, resulting in chains and rings of many different sizes, shapes, and complexities.
The simplest organic compounds contain only the elements carbon and hydrogen, and are called hydrocarbons. Even though they are composed of only two types of atoms, there is a wide variety of hydrocarbons because they may consist of varying lengths of chains, branched chains, and rings of carbon atoms, or combinations of these structures. In addition, hydrocarbons may differ in the types of carbon-carbon bonds present in their molecules. Many hydrocarbons are found in plants, animals, and their fossils; other hydrocarbons have been prepared in the laboratory. We use hydrocarbons every day, mainly as fuels, such as natural gas, acetylene, propane, butane, and the principal components of gasoline, diesel fuel, and heating oil. The familiar plastics polyethylene, polypropylene, and polystyrene are also hydrocarbons. We can distinguish several types of hydrocarbons by differences in the bonding between carbon atoms. This leads to differences in geometries and in the hybridization of the carbon orbitals.
Alkanes, or saturated hydrocarbons, contain only single covalent bonds between carbon atoms. Each of the carbon atoms in an alkane has sp3 hybrid orbitals and is bonded to four other

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Retrieved Text: Thinking in terms of overlapping atomic orbitals is one way for us to explain how chemical bonds form in diatomic molecules. However, to understand how molecules with more than two atoms form stable bonds, we require a more detailed model. As an example, let us consider the water molecule, in which we have one oxygen atom bonding to two hydrogen atoms. Oxygen has the electron configuration 1s22s22p4, with two unpaired electrons (one in each of the two 2p orbitals). Valence bond theory would predict that the two O–H bonds form from the overlap of these two 2p orbitals with the 1s orbitals of the hydrogen atoms. If this were the case, the bond angle would be 90°, as shown in [link], because p orbitals are perpendicular to each other. Experimental evidence shows that the bond angle is 104.5°, not 90°. The prediction of the valence bond theory model does not match the real-world observations of a water molecule; a different model is needed.
Quantum-mechanical calculations suggest why the observed bond angles in H2O differ from those predicted by the overlap of the 1s orbital of the hydrogen atoms with the 2p orbitals of the oxygen atom. The mathematical expression known as the wave function, ψ, contains information about each orbital and the wavelike properties of electrons in an isolated atom. When atoms are bound together in a molecule, the wave functions combine to produce new mathematical descriptions that have different shapes. This process of combining the wave functions for atomic orbitals is called hybridization and is mathematically

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Retrieved Text: Hydrocarbon, an organic chemical compound composed of carbon and hydrogen. Hydrocarbons may be gases, liquids, or solids. In nature, they are found mainly in plants, petroleum, natural gas, coal, and oil shale. Most burn readily and dissolve more readily in alcohol than in water. Some are toxic and some form an explosive mixture with air. Hydrocarbons are used as fuels and solvents and in the manufacture of industrial chemicals, explosives, plastics, synthetic rubber, dyes, drugs, and other products.
More than 100,000 hydrocarbons are known. The main reason there are so many of these compounds is that carbon atoms can unite in many different ways to form complex chain or ring frameworks. Different arrangements of atoms yield different molecules. For example, the formula C30 H62 (30 carbon atoms and 62 hydrogen atoms) represents 4,111,846,763 possible isomers—compounds whose molecules differ only in structure.
In chemistry, compounds closely related in structure to hydrocarbons are called hydrocarbon derivatives. Such compounds consist of carbon, hydrogen, and other elements, usually oxygen, nitrogen, chlorine, phosphorus, or sulfur. They are often named for the hydrocarbons to which they are most closely related. For example, the organic chloride compound most closely related to ethane is called ethyl chloride. Hydrocarbons and their derivatives form a large part of the subject matter of organic chemistry.
Hydrocarbons are divided into two main groups according to structure—aliphatic (or acyclic) hydrocarbons and cyclic hydrocarbons. They are further divided into groups of compounds having similar chemical properties. Members within a group are called homologs, and each complete group is called a homologous series. Neighboring

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Retrieved Text: Not to be confused with benzyl, benzoyl, or phenol.
The structure of the phenyl group attached to an “R” group.
In organic chemistry, the phenyl group or phenyl ring is a cyclic group of atoms with the formula C6H5. Phenyl groups are closely related to benzene and can be viewed as a benzene ring, minus a hydrogen, serving as a functional group. Phenyl groups have six carbon atoms bonded together in a hexagonal planar ring, five of which are bonded to individual hydrogen atoms, with the remaining carbon bonded to a substituent. Phenyl groups are commonplace in organic chemistry. Although often depicted with alternating double and single bonds, phenyl groups are chemically aromatic and show nearly equal bond lengths between carbon atoms in the ring.
Atorvastatin (Lipitor), a blockbuster drug featuring two phenyl and one p-fluorophenyl groups. It is used to lower cholesterol in people with hypercholesterolaemia.
Fexofenadine (Allegra, Telfast), another blockbuster drug, which features a diphenylmethyl group as well as a p–phenylene (C6H4) group. It is an antihistamine used to treat allergies.
Phenylalanine, a synthetic amino acid.
Biphenyl, consisting of two phenyl groups. The two rings tend not to be coplanar.
Chlorobenzene (or phenyl chloride), a solvent.

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Retrieved Text: Chapter L3 Section 4 Organic Compounds The Four Bonds of a Carbon Atom More than 90% of all compounds belong to a group called organic compounds. Organic compounds are covalent compounds composed of carbon-based molecules. Fuel, rubbing alcohol, sugar, cotton, paper and plastic belong to this group. All organic compounds contain carbon. Each carbon atom has four valence electrons so each carbon atom can make four bonds with four other atoms.
Section 4 Organic Compounds The Four Bonds of a Carbon Atom, continued Carbon Backbones Structural formulas are models that are used to show how atoms in a molecule are connected. Each line represents a pair of electrons that form a covalent bond.
Section 4 Organic Compounds The Four Bonds of a Carbon Atom, continued Many organic compounds are based on the types of carbon backbones shown below. Some compounds have hundreds or thousands of carbon atoms as part of their backbone.
Section 4 Organic Compounds The Four Bonds of a Carbon Atom, continued Organic compounds may also contain hydrogen, oxygen, sulfur, nitrogen, and phosphorus. The next slide shows three models of carbon backbones.
Section 4 Organic Compounds Hydrocarbons and Other Organic Compounds Many organic compounds contain several kinds of atoms, but some contain only two. Organic compounds that contain only carbon and hydrogen are called hydrocarbons. There are three types of hydrocarbons: saturated hydrocarbons, unsaturated hydrocarbons, and aromatic hydrocarbons.
Chapter L3 Section 4 Organic Compounds Hydrocarbons, continued Saturated Hydrocarbons An alkane, or saturated hydrocarbon, is a hydrocarbon in which each carbon atom in the molecule shares a single bond with

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Retrieved Text: A team of chemists at Nagoya University has developed a new method for synthesizing nanographenes by zipping up partially fused benzene molecules.
A team of chemists of the JST-ERATO Itami Molecular Nanocarbon Project and the Institute of Transformative Bio-Molecules (ITbM) ay Nagoya University in Japan, together with colleagues, have developed a simple and powerful method for synthesizing nanographenes. Their new approach, recently described in a paper in Science, is expected to lead to significant progress in organic synthesis, materials science and catalytic chemistry.
Nanographenes are one-dimensional, nanometer-wide strips of graphene, made up of benzene units. They are attracting interest as a powerful candidate for next-generation materials, including optoelectronic materials, due to their unique electric characteristics, which depend mainly on their width, length and edge structures. This means that efficient methods for accessing structurally controlled nanographenes are highly desirable.
The ideal synthesis process for nanographenes would be via a ‘LEGO’-like assembly of benzene units, as this would allow the exact number and shape of the molecule to be defined. This direct approach is currently not possible, however, and so the team developed a simple alternative method that controls the formation of the nanographene structure in three key steps.
First, simple benzene derivatives are assembled linearly into two chains, through a cross-coupling reaction. Neighboring links in the two chains are then connected to each other by a palladium catalyst, producing a molecule with three benzene rings bound together in a flat, triangle-like shape. This process then repeats all the way up the chain, effectively zipping the two chains together. The team’s innovation

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Retrieved Text: The key difference between double bond and single bond is that, in a single bond formation, two atoms share one electron pair only between whereas, in a double bond formation, two atoms share two electron pairs.
As proposed by the American chemist G.N.Lewis, atoms are stable when they contain eight electrons in their valence shell. Most of the atoms have less than eight electrons in their valence shells (except the noble gases in group 18 of the periodic table); therefore, they are not stable. These atoms tend to react with each other, to become stable. Thus, each atom can achieve a noble gas electronic configuration. And, this can happen by forming ionic bonds, covalent bonds or metallic bonds. Among these, covalent bonding is special. Single and double bonds come under this category of bonds.
Double bond forms when two atoms share two pairs of electrons between them to fill the valence orbitals. Double bonds are shorter than the single bonds but stronger than them. Sp2 hybridization allows the atoms to form double bonds.
Double bonds can be of two types. Of the two bonds, one is a sigma bond. It forms via the linear overlapping of two sp2 hybridized orbitals. Secondly, the other bond (which we name as the pi bond) forms via the lateral overlapping of two p orbitals.
The common example of a molecule with a double bond is ethylene. In ethylene, the double bond is between two carbon atoms. However, other than between similar atoms, this type of bonds can form between different atoms too as in

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Retrieved Text: (e) H2CO (Formaldehyde) (f) C6H6 (Benzene).
3. What valence atomic orbitals formed the bonds of the compounds listed in problem (2)?
4. What compound listed in problem (2) has Pi (π) bonds that cannot be entirely described as localized Pi (π) bonds?
5. Write the general representative strings for Sigma (σ) bonds and Pi (π) bonds.
1(a) Resonance structures (also called resonance forms): the different Lewis structures that are equally acceptable descriptions of a single molecule.
(b) Sigma (σ) bond: a covalent bond in which the electron density is concentrated symmetrically about the line joining the nuclei (internuclear axis) of the bonded atoms. In other words, a covalent bond in which the internuclear axis passes through the middle of the region of orbital overlap (figure 9.16).
Pi (π) bond: a covalent bond in which the electron density is concentrated above and below the internuclear axis of the bonded atoms. In other words, a covalent bond in which the line passing through the middle of the region of orbital overlap is perpendicular to the internuclear axis of the bonded atoms (figure 9.17).
Localized electrons: σ and π electrons totally associated with the atoms that form the bond. Such bonds are localized bonds.
Delocalized electrons: electrons not totally associated with the atoms that form the bond. Such bonds are delocalized bonds. Delocalized bonds are commomly encountered in molecules that have two or more resonance structures involving π bonds. Such bonds are called delocalzed π bonds.
2(a) The valence-shell configuration of H = 1s1. Two s orbitals overlap to form H2. The internuclear axis of the atoms passes

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Retrieved Text: Scientists may possibly have found clues to what seems to be the path to forming life's building blocks in space.
Published in Nature Astronomy journal the new study reveals that lab experiments carried out by scientists to retrace the chemical steps leading to the creation of complex hydrocarbons in space, showing pathways to forming 2-D carbon-based nanostructures in a mix of heated gases. Scientists say their findings could help explain the presence of pyrene, which is a chemical compound known as a polycyclic aromatic hydrocarbon, and similar compounds in some meteorites.
Scientists explain that Pyrene has a molecular structure composed of 16 carbon atoms and 10 hydrogen atoms. Researchers found that the same heated chemical processes that give rise to the formation of pyrene are also relevant to combustion processes in vehicle engines, for example, and the formation of soot particles.
The latest study builds on earlier work that analyzed hydrocarbons with smaller molecular rings that have also been observed in space, including in Saturn's moon Titan - namely benzene and naphthalene.
Pyrene belongs to a family known as polycyclic aromatic hydrocarbons, or PAHs, that are estimated to account for about 20 percent of all carbon in our galaxy. PAHs are organic molecules that are composed of a sequence of fused molecular rings. To explore how these rings develop in space, scientists work to synthesize these molecules and other surrounding molecules known to exist in space.
For this study, researchers explored the chemical reactions stemming from a combination of a complex hydrocarbon known as the 4-phenanthrenyl radical, which has a molecular

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Retrieved Text: It’s well understood by physicists that stars are responsible for building most of the abundance of elements heavier than helium, through nuclear fusion. Recent observations from LIGO and optical counterparts of neutron star collisions indicate that these processes, and not supernovae, may be responsible for constructing certain elements such as gold and platinum.
But another considerable mystery is how complex chemistry occurs in outer space - how do these elemental building blocks meet and form complex hydrocarbons, like those that seem to be required for carbon-based life?
Now, new experiments have looked at conditions similar to those in outer space to assess the feasibility of processes to form a complex hydrocarbon molecule, pyrene. The study was an international collaboration between experimentalists at the Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab), astronomers from the University of Hawaii at Manoa, and theoretical chemists to understand the chemical reactions at Florida International University. The study was published March 5, in Nature Astronomy.
Hydrocarbons can include a vast array of different chemical compounds, due to the rich chemistry made possible by the hydrogenic bonding; molecular rings can form to provide a huge range of substances, many of which are used by biological organisms. Examples that have been detected in space include benzene and naphthalene. Pyrene is a slightly more complex molecule, consisting of 16 carbon atoms and ten hydrogen atoms; you can view it as four rings of benzene fused together. These polycylic aromatic hydrocarbons (PAHs) are considered possible precursors for the origin of life, and they are associated with the

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Retrieved Text: Crude oil, as it is taken from the earth, is a very complex mixture of hydrocarbons.
As might be expected, the term hydrocarbon refers to the hydrogen and carbon atoms linked together and forming a majority of the individual molecules that are present. Having been transformed from living organisms being subject to heat and pressure over millions of years, the crude is termed to be an “organic” material. In addition to hydrogen and carbon, there are small amounts of other atomic elements that are present and mostly incorporated into the hydrocarbon molecules. The most common of these are nitrogen and sulfur. As part of the hydrocarbon, they are referred to as “hetero-” atoms. Heavier crude may also contain some inorganic materials such as nickel, vanadium, and iron, which are removed during refining.
Hydrocarbons form in an extraordinarily large number of configurations. They range in size from the simplest methane molecule, which contains one carbon atom and four hydrogens, to heavy asphaltic resins with structures that have not been fully mapped. Because we are dealing with mineral oil–based lubricants, we are interested in molecules of a size that fit into the range of approximately 15 to 95 carbon atoms long, corresponding roughly to a boiling range of about 300–700°C. In addition, as the number of carbon atoms in a molecule increase, the number of different ways that a molecule can be structured increases dramatically. Although many different arrangements of molecules may be imagined, for practical purposes, petroleum hydrocarbons are generally classified in a limited number of ways.
Consider the list

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Retrieved Text: Most of the organic reactions occur through the involvement of certain chemical species.These are generally short lived and highly reactive and hence cannot be isolated.These short lived highly reactive chemical species through which the majority of the organic reactions occur are called reactive intermediates.
Example: Carbocation, carboanion, free radical, carbenes and nitrenes.
Chemical species bearing a positive charge on carbon and carrying six electrons in its valence shell are called carbocation.
These are formed by heterolytic cleavage of the covalent bonds in which the leaving group takes away with it the shared pair of electrons.
Carbocation are also formed during dehydration of alcohols in presence of conc. H2SO4 at 430-440 K.
Carbocation are classified as primary (1°) , secondary (2°) and tertiary (3°) according as the positive charge is present on a primary, secondary and tertiary carbon atom.
An alkyl group has +I effect .When an alkyl group is attached to a positively charged carbon atom of a carbocation , it tends to release electrons towards that carbon.In doing so, it reduces the positive charge on the carbon.In other words, the positive charge gets dispersed and the alkyl group becomes somewhat positively charged.This dispersal of the positive charge stabilizes the carbocation.
Stability decreases as +I effect of the alkyl group decreases.
Carbocations in which the positively charged carbon atom is attached to a double bond or a benzene ring are stabilized by resonance.
The presence of electron-donating group such as -CH3, -OCH3, -OH in the benzene ring increases the stability while the presence of electron withdrawing group such as -NO2 ,-CN , -COOR , -Cl

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Retrieved Text: There are millions of organic molecules, but few examples of carbon molecules or nanomaterials such as nanotubes or graphene with extended bonding, despite hundreds of theoretical investigations of their beautiful, symmetric structures and superlative and potentially useful properties. The NSF CNC's mission is to define the chemistry to produce a new class of organic molecules that have pervasive covalent bond connectivity in multiple dimensions and explore their properties for scientific and technological application. This mission is inspired by its discovery that solid, polycrystalline molecular benzene and other aromatic molecules assemble upon compression into a hexagonal crystal of one dimensional carbon nanothreads with tetrahedral, diamond-like sp3 bonding, as shown above. The carbon atoms in the benzene molecules are color-coded to show where they end up in the nanothread crystal, which is recovered to ambient pressure. The pink exterior hydrogens allow nanothreads to collectively function as both hydrocarbon molecules and nanomaterials, in contrast to sp2 bonded carbon nanotubes, opening new frontiers for design of structure and properties. The Center’s main phase I goal is to develop a detailed, actionable and fundamental understanding of the synthesis mechanism of nanothreads, to enable both synthesis scale-up and the production of new threads of diverse composition, properties, and structure.
Team member Vin Crespi (dreaming here) gave a Physics Colloquium at Penn State, entitled "Secret Dreams of Atoms". His talk illustrated modes and habits of thought that encourage discovery and innovation, such as nanothreads.
Team member Roald Hoffmann, shown here with former graduate student Xiang Li, gave two talks on new forms of carbon, including

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Retrieved Text: The increasingly large number of organic compounds identified with each passing day, together with the fact that many of these compounds are isomers of other compounds, requires that a systematic nomenclature system be developed. Just as each distinct compound has a unique molecular structure which can be designated by a structural formula, each compound must be given a characteristic and unique name.
Such common names often have their origin in the history of the science and the natural sources of specific compounds, but the relationship of these names to each other is arbitrary, and no rational or systematic principles underly their assignments.
A rational nomenclature system should do at least two things. First, it should indicate how the carbon atoms of a given compound are bonded together in a characteristic lattice of chains and rings. Second, it should identify and locate any functional groups present in the compound. Since hydrogen is such a common component of organic compounds, its amount and locations can be assumed from the tetravalency of carbon, and need not be specified in most cases.
 A root or base indicating a major chain or ring of carbon atoms found in the molecular structure.
 A suffix or other element(s) designating functional groups that may be present in the compound.
 Names of substituent groups, other than hydrogen, that complete the molecular structure.
As an introduction to the IUPAC nomenclature system, we shall first consider compounds that have no specific functional groups. Such compounds are composed only of carbon and hydrogen atoms bonded together by sigma bonds (all carbons

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Retrieved Text: A major class of organic compounds where carbon and hydrogen molecules are arranged in straight or branched chains. A type of hydrocarbon . Includes alkane s, alkene s, and alkyne s.
An organic molecule containing carbon and hydrogen atoms in straight or branched chains, where all of the carbon-carbon bonds are single bonds. One of three major classes of aliphatic hydrocarbon s.
An organic molecule containing carbon and hydrogen atoms in straight or branched chains, where at least one carbon-carbon bond is a double bond. One of three major classes of aliphatic hydrocarbon s.
An organic molecule containing carbon and hydrogen atoms in straight or branched chains, where at least one carbon-carbon bond is a triple bond. One of three major classes of aliphatic hydrocarbon s.
Molecules which are almost entirely carbon and hydrogen, but have had at least one chlorine atom introduced to them that has replaced one of their hydrogen atoms.
A hydrocarbon (molecule of carbon and hydrogen only) with 27 carbon atoms that is the parent structure of all mammalian steroid s.
Any of several enzyme s that put double bonds into the hydrocarbon areas of fatty acid s.
Any in a family of over 200 chlorinated organic chemicals (all heterocyclic hydrocarbons). The term is most commonly applied to a particular chemical, 2,3,7,8-tetrachlorodibenzo-paradioxin (2,3,7,8-TCDD, simply called TCDD), which is an impurity in the defoliant Agent Orange and in the pesticide 2,4,5-T (see auxin ). Dioxins are also produced when chlorinated materials such as plastics are burned. Dioxins are known to cause skin diseases (chloracne), birth defects, miscarriages, and cancer .
A

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Retrieved Text: Benzene is sometimes referred to as an aromatic compound as opposed to the majority of other organic molecules that you have so far studied that are found in chains and sometimes referred to as aliphatic compounds.
Aromatic substances are said to have an unsaturated ring of atoms whereas aliphatic substances open chains. The word ‘arene’ is sometimes used in place of aromatic.
Benzene has the formula C6H6. Its structure was first proposed by the German chemist Friedrich August Kekulé in 1865. Its molecular formula had been known for some time, but he was the first chemist to propose a structure for it.
This was ground breaking at the time as up to this point, organic chemists had only thought of organic substances existing as aliphatic compounds, i.e. chains of atoms. However, it is not possible to have an arene of C6H6 – it just doesn’t work.
Kekule was working on this problem for a long time and not having any luck. At the 25th anniversary of the discovery of its structure he claimed that on the day he worked out the structure, he was daydreaming about the possible structure of the molecule and imagined a snake eating its tail, forming a ring structure, allowing him to realise the molecule was aromatic as opposed to aliphatic.
This was groundbreaking at the time and opened up a whole new branch of chemistry. Don’t underestimate the importance of this discovery!
Of course now, we know much more about benzene. It does not contain alternating double and single bonds but a system of delocalised electrons above

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Retrieved Text: Thanks to specialised microscopes, we have long been able to see the beauty of single atoms. But strange though it might seem, imaging larger molecules at the same level of detail has not been possible – atoms are robust enough to withstand existing tools, but the structures of molecules are not. Now researchers at IBM have come up with a way to do it.
The earliest pictures of individual atoms were captured in the 1970s by blasting a target – typically a chunk of metal – with a beam of electrons, a technique known as transmission electron microscopy (TEM).
Later refinements of this technique, such as the TEAM project at the Lawrence Berkeley National Laboratory in California achieved resolutions of less than the radius of a single hydrogen atom. But while this method works for atoms in a lattice or thin layer, the electron bombardment destroys the arrangement of atoms in molecules.
Other techniques use a tiny stylus-like scanning probe to explore the atom-scale world. One method uses such a probe to measure the charge density associated with individual atoms – a technique called scanning tunnelling microscopy (STM).
Another, called atomic force microscopy (AFM), measures the attractive force between atoms in the probe and the target. The image is created by bumping the probe over the atoms of the molecule – much in the way we might feel our way around in a dark bedroom.
Both methods build up a picture of a target’s surface and should be suitable for imaging individual molecules. But they have not been able to approach

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Retrieved Text: A team of Dutch and German scientists decoded the inner dynamics of an important model system of organic chemistry. The investigation of the benzene dimer solves a 20-year old mystery, reported the group headed by Melanie Schnell from the Hamburg Center for Free-Electron Laser Science (CFEL). Her study was selected as cover story of the scientific journal “Angewandte Chemie International Edition”and categorised as “very important paper”(VIP) by the evaluators and publishers. CFEL is a joint enterprise from DESY, the Max Planck Society and the University of Hamburg.
Two benzene rings form a dimer.
Benzene is the most basic so-called aromatic compound. It consists of a ring of six carbon atoms with one hydrogen atom attached to each carbon atom. The benzene double molecule, the so-called dimer, is the prototype for the investigation of a complete class of chemical bonds, the van der Waals bond. This is a relatively weak bond between molecules which plays an important role in many fields. An illustrative example is geckos which, thanks to the van der Waals force between the very fine hairs on their footpads and the surface, are able to move on the ceiling.
In the benzene dimer, both benzene rings attach to each other like a T. One ring forms the cap and one the stem; with the stem being slightly tilted to the border of the cap and not in its centre. In spite of this asymmetric structure, the benzene dimer behaves like a symmetric spin top when investigated with micro waves. This was not understood for a long time.

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Retrieved Text: In this post we introduce “aromaticity”, a term for describing a collection of three [note] main properties that distinguish benzene from (hypothetical) cyclohexatriene.
[This collection of features is not unique to benzene. We’ll describe other aromatic molecules in the next post. See “Rules For Aromaticity“].
In the sections below we go through each of these three features in detail.
What’s “resonance energy” again? Let’s start with cyclohexene and build our way up.
In case you can’t picture it, cyclohexene is a six membered ring containing a single pi ( π)bond.
If you treat cyclohexene with hydrogen gas (H2) in the presence of a noble metal catalyst such as Pd supported on carbon (Pd/C), you form cyclohexane. The reaction liberates 28.6 kcal/mol (120 kJ/mol) of heat.
If you’re in second semester organic chemistry, there’s no doubt you’ve seen this reaction before.
Now for a slightly more interesting question. What happens to the enthalpy of hydrogenation when we add a second double bond adjacent to the first one: 1,3-cyclohexadiene. (There’s another isomer – 1,4 cyclohexadiene – which we won’t concern ourselves with for this example, because the double bonds are not conjugated).
The enthalpy of hydrogenation in this case is 55.2 kcal/mol (231 kJ/mol) ; almost, but not quite double of that for cyclohexene (2 x 28.6 = 57.2 kcal/mol).
This is still an interesting result, because it tells us that having those two double bonds together results in a little bit of extra stability (2 kcal/mol) versus two isolated pi bonds.
We call this extra stabilization (2 kcal/ mol) “resonance energy” . It’s a consequence of conjugation

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Retrieved Text: Benzene, with the delocalization of the electrons indicated by the circle.
In chemistry, delocalized electrons are electrons in a molecule, ion or solid metal that are not associated with a single atom or a covalent bond. The term is general and can have slightly different meanings in different fields. In organic chemistry, this refers to resonance in conjugated systems and aromatic compounds. In solid-state physics, this refers to free electrons that facilitate electrical conduction. In quantum chemistry, this refers to molecular orbitals that extend over several adjacent atoms.
In the simple aromatic ring of benzene the delocalization of six π electrons over the C6 ring is often graphically indicated by a circle. The fact that the six C-C bonds are equidistant is one indication of this delocalization. In valence bond theory, delocalization in benzene is represented by resonance structures.
Delocalized electrons also exist in the structure of solid metals. Metallic structure consists of aligned positive ions (cations) in a "sea" of delocalized electrons. This means that the electrons are free to move throughout the structure, and gives rise to properties such as conductivity.
In diamond all four outer electrons of each carbon atom are 'localized' between the atoms in covalent bonding. The movement of electrons is restricted and diamond does not conduct an electric current. In graphite, each carbon atom uses only 3 of its 4 outer energy level electrons in covalently bonding to three other carbon atoms in a plane. Each carbon atom contributes one electron to a delocalized system of electrons that is also a part of the

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Retrieved Text: In excited carbon atom there are four half-filled orbitals available for bond formation resulting in the formation of four covalent bonds.
It should be noted, however, that the four half-filled valence orbitals are not equivalent, there being three p-orbitals and one s-orbital. As such the four bonds would not be equivalent, the bond using the s-orbital would be different from the three bonds using the p-orbital. Actually carbon forms many compounds such as carbon tetrachloride in which all the four bonds are equivalent. To account for the equivalence of the four bonds, it is assumed that the four available orbitals of carbon, the 2s and three 2p orbitals are mixed or hybridized in a manner as to result in four equivalent orbitals.
The phenomenon of intermixing of orbitals of the same atom having the slightly different energies to form new orbitals which have identical shapes and equivalent energies is known as hybridisation.
Carbon atom can undergo three types of hybridisation in its compounds.
Carbon in methane is sp3 hybridised Here, one orbital of 2s-sub-shell and three orbitals of 2p-sub-shell of excited carbon atom undergo hybridisation to form four sp’3 hybrid orbitals. The process involving promotion of 2s-electron followed by hybridisation is shown in Fig. 36.4.
The carbon atom lies at the centre of the tetrahedron while the four hydrogens occupy the four comers or vertices of tetrahedron as shown in Fig. 36.5.
In ethane molecule, both the carbon atoms are sp3 hybridised. The geometry around both the carbon atoms is tetrahedral as shown in Fig. 36.6. C-C bond length is 1.54 A

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Retrieved Text: Hydrocarbons containing at least three carbon atoms and non-aromatic carbon-to-hydrogen bonds are converted into hydrocarbons containing a new carbon-to-carbon linkage and having a higher carbon to hydrogen ratio by heating with an hydrogen-accepting olefine and a proportion of iodine (or hydrogen iodide, alkyl iodides or other compound which liberates iodine under the reaction conditions) of at least 0.05 mol. per mol. of hydrocarbon to be converted at at least 300 DEG C. to effect carbonto-hydrogen bond cleavage in the hydrocarbon feed and convert the olefine to paraffin. Conversions which may be effected are dehydrogenation of alkanes or aralkanes, e.g. isobutane to isobutene, n-butane to butenes and butadiene, ethyl benzene to styrene, o-methyl ethyl benzene to o-methyl styrene, and n-butyl benzene to 4 - phenyl - butadiene - 1,3; dehydrocoupling, e.g. propylene to diallyl, isobutene to dimethallyl, toluene to dibenzyl and stilbene; dehydrocyclization often with aromatization, e.g. n-hexane to benzene, n-heptane to toluene, n-octane to m-xylene and ethyl benzene, 2,5-dimethyl hexane to p-xylene, hexadiene-1,3 to benzene, hexane-1 to cyclohexene, o-diethylbenzene to naphthalene, o-methyl propyl benzene to naphthalene, n-butyl benzene to naphthalene, 2,3-diethyl naphthalene to anthracene, butylcyclohexane to naphthalene, and butylcyclopentane to indene; and dehydrogenation, often with aromatization of hydroaromatic hydrocarbons, e.g. cyclohexane to cyclohexene and benzene, and methylcyclohexane to toluene. In the case of acyclic hydrocarbons containing a quaternary carbon atom, dealkylation and/or isomerization may occur, e.g. 2,2,5-trimethylhexane gives p- and m-xylenes. The olefine used should be such that the sum of the standard free energy change for the hydrogenation of the olefine to the corresponding paraffin

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Retrieved Text: Because they share a common composition with their liquid state, ice molecules also consist of the same 2 to 1 ratio of hydrogen and oxygen atoms, the well-known H2O molecule. The shape of this molecule, the oxygen atom at the center with the two hydrogen atoms separated by an angle of 104.52°, dictates the structure of the solid, crystalline ice. All naturally occurring ice crystals are hexagonal in shape and all snowflakes reflect this basic six-sided crystal habit. The crystal lattice consists of linked hexagonal rings of water molecules with considerable open space in the center of the ring.
Under artificial laboratory conditions of very high pressures and low temperatures, ice can be forced to crystallize in a number of allotropic forms that are stable only under those particular conditions. Crystallization can occur in these laboratory situations in one of several non-hexagonal forms. This is similar to the way that carbon atoms may crystallize to form graphite or, under more extreme conditions, diamond. The conditions under which the alternate forms might be created do not occur naturally on Earth. They may, however, be present on other bodies in space.
The crystalline structure of ice may be deformed by stress, such as the weight of overlying ice on the deeper portions of a glacier. One type of deformation involves shearing of the crystal lattice along parallel planes. Recrystallization, on the other hand, entails the change in the shape and orientation of crystals within the solid. Both of these processes produce the phenomenon known as creep, responsible for the flowing

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Retrieved Text: Pyrrole is an example of a heteroaromatic compound: it contains a heteroatom (atom that is not carbon or hydrogen, such as N, O, S, etc.), and is aromatic.
Because pyrrole is aromatic, we should be able to draw many resonance forms- usually as many resonance forms as sides (in this case, five sides, so five resonane forms).
One of the rules for aromaticity is that all atoms shoudl be sp2 hybridized. But the nitrogen in pyrrole is sp3 hybridized, so how is it still aromatic? Because in 4/5 of its resonance forms the nitrogen is sp2 hybridized; the real picture of pyrrole looks more like the structure on the left (dashed circle) than any individual resonance form.
MendelSet practice problem # 583 submitted by Matt on July 9, 2011.

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Retrieved Text: Density functional calculations accurately reproduce the known bond lengths for C60F18, shown recently (single crystal X-ray structure) to possess a fully aromatic hexagonal ring, and they correctly predict the planarity of this ring. Isostructural C60H18 is also calculated to have an aromatic benzenoid hexagonal ring, and to be marginally less planar. The four benzenoid hexagonal rings of T symmetry C60H36 and C60F36, and the three benzenoid rings of C3 symmetry C60H36 and C60F36 are predicted to be aromatic, with both the T symmetry and the fluorinated species again having the slightly shorter bond lengths and the greater planarity; by these measures T-C60F36 is as aromatic as C60F18. In another C3v isomer of C60H18, which had been predicted (AMI) to be thermodynamically more stable than the known isomer, density functional calculations show the central benzenoid ring to have slightly greater bond alternation, greater bond lengths, to be less planar and the molecule to be overall less stable than the known isomer; this is attributed to the greater strain in the three adjacent pentagonal rings. Sites for ether formation are conjectured based on the recent finding that oxygen inserts into long FC-CF bonds of fluorofullerenes.

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Retrieved Text: In this case we can speak about partial charge of atoms. We will give the definition of partial charge intuitively rather than exactly. A simple definition of partial charge starts from a basic two-atom model in which atoms A and B have different electron structures. In the figure below, the "boundary" of the valence shell is denoted with blue and green solid lines. This boundary is chosen to create a fixed control volume with a definite probability (near to 100%) of finding all electrons belonging to the atom on the inside.
In the intermediate state the nuclear distance of A and B decreases. As they draw closer to each other, each of their electron clouds is polarized to a different degree. Although the electrons of both A and B have partially moved outside of the control volume, this effect is greater in atom B being the more polarizable atom. The more polarizable an atom is, the more electrons will flow out of its control volume so that the atom will become more positive relative to its initial state.
In the final state the two atoms reach the equilibrium nuclear distance and the two electron clouds overlap. Using the control volumes and electron clouds in the figure, atom B becomes more positively charged and atom A becomes more negatively charged relative to their initial states. In this way, partial charge of an atom in the molecule is measured as a charge flow out of or into the atom's control volume.
χν is the orbital electronegativity of the atom.
Iν is the

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Retrieved Text: Lipids are nonpolar organic molecules that are insoluble in polar water but soluble in nonpolar organic solvents like ether, alcohol, and chloroform. Lipids show hydrophobic behavior. The behaviour is associated with the chemical structures of lipids. Lipids have high proportion of C-1-I bonds. C-1-I is non-polar in character. Phospholipids and cholesterol are lipids. They are important constituents of cell membranes. The most common lipids in plants and animals are fats.
oxygen atoms. Some figs also contain small amounts of phosphorus and nitrogen. They contain a much smaller proportion of oxygen than carbohydrates. For example the formula of the fat tristearin is C5,F111006.
The building blocks of fat molecules are fatty acids and glycerol. Fatty acids contain long hydrocarbon chains bonded to carboxyl (COOH) groups. Glycerol is a three-carbon alcohol, with each carbon bearing a hydroxyl (OH) group. Three fatty acid molecules combine with one glycerol molecule. They are attached to the three carbon atoms in the glycerol backbone.
The fats with three fatty acids are called triglyceride neutral fat or triacylglycerol. The glycerol portion of every fat molecule is the same. But there are many kinds of fatty acids. Therefore, there are many kinds of fats. Fatty acid molecules differ in the length of their carbon chains aud in the ways the carbon atoms combine. The most common are e :en-numbered chains of 14 to 20 carbons.
Unsaturated fats: The% have double bonds. Their chains bend at the double bonds. So the fat molecules cannot align closely w ith one another. Therefore. they have low melting points. Thus the fat

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Retrieved Text: To describe the bonding in benzene and the way typical reactions of benzene differ from those of the alkenes.
Next we consider a class of hydrocarbons with molecular formulas like those of unsaturated hydrocarbons, but which, unlike the alkenes, do not readily undergo addition reactions. These compounds comprise a distinct class, called aromatic hydrocarbons, with unique structures and properties. We start with the simplest of these compounds. Benzene (C6H6) is of great commercial importance, but it also has noteworthy health effects.
The formula C6H6 seems to indicate that benzene has a high degree of unsaturation. (Hexane, the saturated hydrocarbon with six carbon atoms has the formula C6H14—eight more hydrogen atoms than benzene.) However, despite the seeming low level of saturation, benzene is rather unreactive. It does not, for example, react readily with bromine, which, is a test for unsaturation.

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Retrieved Text: Born in 1829 in Darmstadt, Germany, Kekulé was talented at drawing and mathematics. He followed the wishes of his affluent family and attended school with the intention of becoming an architect. While at the University of Giessen, however, he was most intrigued by Justus von Liebig’s lectures in chemistry. He switched his academic focus to chemistry and studied in France, Switzerland, and England.
By 1852 Kekulé had worked in various labs across the continent and earned a Ph.D. from the University of Giessen. Taking advantage of numerous opportunities for advanced study, Kekulé worked in hospitals, universities, and private labs until he began to teach organic chemistry in 1856 at the University of Heidelberg.
During the next few years Kekulé turned his attention to the behavior of carbon atoms. He formulated the idea that carbon could be tetravalent; that is, carbon could have a valence of four, which would enable it to bond with both metals and nonmetals. He punished this theory in 1857. Soon after Kekulé expanded on this to propose that in compounds containing more than one carbon atom, the carbon atoms could be joined in long chains. There still remained molecules that did not fit this framework. Kekulé worked on this problem for many years. He used his mathematical abilities and spatial skills to help determine the structure of compounds.
One night Kekulé sat doting in front of his fire. As he gazed into the flames, he dreamt that the fingers of fire seemed to become snakes that chased themselves in circles. One even caught its tail

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Retrieved Text: Formula and structure: The propane chemical formula is C3H8 and is extended formula is CH3CH2CH2. Its molar mass is 44.097 g mol-1. The molecule is formed by a chain of three carbon atoms which are bound to 3 or 2 hydrogen atoms in order to complete the 4 bonds required to complete the octet of Lewis structure. The carbon atoms are sp3 hybridized, thus the molecule has free rotation and a tetrahedral conformation. Its chemical structure can be written as below, in the common representations used for organic molecules.
Occurrence: Propane is found as a constituent of natural gas. It is also present in crude oil together with butane, methane, butylene, isobutylene and others where is extracted from distillation.
Preparation: Propane is producing by the distillation of crude oil or by extraction from natural gas. It is not largely synthesized by chemical industry and there is a few methods for producing it. In crude oil extraction, it is a sub-product in the process to obtain gasoline and other more commercial substances and it is removing to avoid pipelines problems.
Physical properties: Propane is a colorless and odorless gas, but it is shipped as liquefied compressed gas. These melting and boiling point are -187.6 ºC and -42.1 ºC, respectively. Its density is 2.009 g mL-1. Propane, in a pure form or when combined with methane, ethane or propane, can easily ignite forming vapors lighter than air. It is not soluble in water, but is slightly soluble in acetone, ethanol and more soluble in ether, chloroform and benzene.
Chemical properties: Propane is

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Input Text: Answer the following question given this paragraph: 

All other nervous tissue in the body makes up the peripheral nervous system, which has two major divisions. The sensory division carries messages from sense organs and internal organs to the central nervous system. The motor division carries messages from the central nervous system to muscles, internal organs, and glands throughout the body. The motor division is further divided into parts that control involuntary or voluntary responses.


Q: Which division of the peripheral nervous system carries messages from sense organs and internal organs to the central nervous system?

 Choices:

- extrasensory division

- sensory division

- vascular division

- neural division

A:

Target Text: sensory division

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Retrieved Text: 1. The Somatic Nervous System and The Autonomic Nervous System.
2. The Somatic Nervous System transmits sensory messages to carry messages from the central nervous system.
3. The Autonomic Nervous System regulates the body's vital functions, such as heartbeat, breathing, digestion, and blood pressure.
4. The Parasympathetic Nervous System and Sympathetic Nervous System.
5. The Parasympathetic Nervous System.
2. Transmits sensory messages to the central nervous system.
3. Regulates the body's vital functions, such as heartbeat, breathing, digestion, and blood pressure.
What is the function of the somatic nervous system? To carry messages from the voluntary muscles and sense organs.
What is the functions of the autonomic nervous system? It regulates the body's vital functions, such as heartbeat, breathing, digestion, and blood pressure.
1. The two divisions are the somatic nervous system and the autonomic nervous system.
2.The function is to carry messages from the voluntary muscles and sense organs.
3.Regulates the body's vital functions, such as heartbeat, breathing, digestion, and blood pressure.
4. The sympathetic and the parasympathetic nervous system.
2. Carry messages from volentary muscles and sense organs.
3. It regulates bodily functions.
1.)divisions of the peripheral nervous system is the somatic nervous system and the automatic nervous system.
2.)transmits sensory messages to the central nervous system.
3.) regulates the body's vitual functions, such as heartbeat, breathig, digestion, and blood pressure.
The two divisions of the peripheral nervous system are the somatic nervous system and the autonomic nervous system. The functions of the somatic nervous system is to carry messages from the voluntary muscles and sense organs. The function of the autonomic nervous system is regulating the body's vital functions, such as

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Retrieved Text: The autonomic nervous system is unique in that it requires a sequential two-neuron efferent pathway; the preganglionic neuron must first synapse onto a postganglionic neuron before innervating the target organ. In the sympathetic system, the ganglia are arranged in two chains adjacent to the spinal column. In the parasympathetic system, the ganglia are located adjacent to or within the organs they supply.
Interneurons create neural circuits, enabling communication between sensory or motor neurons in the peripheral nervous system and the creation of extensive networks within the central nervous system.
A reflex arc is a neural pathway that controls an reflex action.
The somatic nervous system (voluntary nervous system) is the part of the peripheral nervous system consisting of the afferent and efferent nerves associated with skeletal muscle voluntary control of body movements.
The autonomic nervous system is the division of the peripheral nervous system influencing the function of internal organs, a control system acting largely unconsciously to regulate bodily functions such as the heart rate, digestion, and respiratory rate.

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Retrieved Text: Adrenergic nerve fibre, nerve fibre that releases the neurotransmitter norepinephrine (also known as noradrenaline) at the synapse, or junction, between a nerve and its end organ, which may be a muscle, gland, or another nerve. Adrenergic nerve fibres make up the sympathetic nervous system, one of two peripheral nervous systems controlling involuntary activities, such as digestion, respiration, and circulation.
Adrenergic fibres innervate smooth muscle, cardiac muscle, visceral glands, and various central nervous system structures and sense organs; their action is opposite to the inhibiting action of the cholinergic fibres of the parasympathetic system. Peripheral adrenergic neurons integrate signals from other nerves of the central nervous system and peripheral sense organs; an adrenergic nerve impulse is triggered when one nerve fires repeatedly or when several nerves fire simultaneously.

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Retrieved Text: Nervous System Functions And Organs - May 19, 2018 by stefan.
Post tagged: central nervous system organs and functions, human nervous system organs and functions, nervous system functions and organs, nervous system main organs and their functions, nervous system organs and functions quizlet, nervous system organs and functions table, peripheral nervous system organs and functions.
11 photos of the "Nervous System Functions And Organs"
Related Posts to "Nervous System Functions And Organs"

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Retrieved Text: Invertebrate animals show varying degrees of complexity in their nervous systems, but it is in the vertebrate animals (phylum Chordata, subphylum Vertebrata) that the system reaches its greatest complexity.
All of the fibers of the autonomic nervous system are motor channels, and their impulses arise from the nerve tissue itself, so that the organs they innervate perform more or less involuntarily and do not require stimulation to function.
Three kinds of tissue are found in the nervous system, nerve fibres, nerve cells, and a supporting tissue called neuroglia.
The white consists of medullated fibres belonging to the central nervous system, and these are splanchnic afferent or centripetal, and efferent or centrifugal.
The system of the lateral line or acustico-lateralis component is sometimes regarded merely as a subdivision of the somatic sensory.
The nervous system is an internal communication system, relaying signals with short electrical impulses.
The parasympathetic nervous system normalizes the body by balancing it to the state it was in before the stimulus occurred.
Nervous tissue is composed of two main cell types: neurons and glial cells.
The nervous system coordinates rapid responses to external stimuli.
The Peripheral Nervous System (PNS) connects the CNS to other parts of the body, and is composed of nerves (bundles of neurons).
The nervous system is composed of all nerve tissues in the body.
The peripheral nervous system includes all nerves not in the brain or spinal cord and connects all parts of the body to the central nervous system.
In the peripheral nervous system, a chemical neurotransmitter carries the nerve impulses from neuron to neuron across a synapse (space between

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Retrieved Text: Our body is made up of different body parts which have specific functions to play. Some of them are related to our brain, some to stomach and some to lower part of the body. We won’t be able to perform in a normal manner even if a single part of our body stops working. Just like other parts of the body, we have our nervous system. The disorders related to our nervous system along with the prevention and treatment comes under the medical term which is known as Neurosurgery. IBS hospitals have the Best neurosurgeons in Delhi.
1. Central nervous system – it is that part of the nervous system that consists of brain and spinal cord. It has the word central in it because it coordinates the activity of all the parts of our body. Spinal cord carries information from brain to rest of the body whereas the function of the brain is to receive the information and then transfer it to other parts.
2. Peripheral nervous system – it is that part of the body which consists of all the nerves and ganglia that are outside of our brain and spinal cord. The main function of our peripheral system is to connect our central nervous system to other organs and act as a bridge between central nervous system and the rest of our body.
1. External injuries such as blow to our head.
2. Vehicular accidents with direct consequences to our head.
3. Mishaps in contact sports.
4. Internal injuries that are caused by tumors.
IBS Hospitals is the best hospital

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Retrieved Text: Definition: The process whose specific outcome is the progression of the peripheral nervous system over time, from its formation to the mature structure. The peripheral nervous system is one of the two major divisions of the nervous system. Nerves in the PNS connect the central nervous system (CNS) with sensory organs, other organs, muscles, blood vessels and glands.

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Retrieved Text: The Central Nervous System consists of the Brain, which is the Headquarters of the Nervous System, and the spinal cord where agents of both the CNS and PNS team up to share information acquired from the H.Q.
The Peripheral Nervous System is somewhat like the messenger service of the Nervous system. It is broken down into two major parts the afferent division and the efferent division.
1. The Afferent Division: This division of the PNS holds Humansvilles most elite message carriers. These messengers can take messages all over the body and delivers them to different CNS research labs.
2. The Efferent Division: This division of the PNS carriers motor commands to muscles and glands all over the body. This division is further broken down into two subdivisions the autonomic and somatic branch.
Somatic Nervous System This division makes sure we have control over our skeletal muscles.
Autonomic Nervous System This branch of the PNS provides automatic, involuntary control of Smooth muscle and glandular activity and secretions. The ANS also has its own support units. These are the highly specialized lab workers of the Sympathetic and Parasymathetic divisions.
Sympathetic Division: Preganglionic fibers from the thoracic and lumbar spinal segments synapse in ganglia near the spinal cord. The Sympathetic division is often called the fight or flight system as the scientists of these labs work almost exclusivly with Metabolism and it can increase the energy in the human body.
Parasympathetic Division: Preganlionic fibers from the brain and the sacral spinal segments synapse on neurons of the intramural ganglia located near or in the the tissues

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Retrieved Text: The nervous system can be divided into two major subdivisions: the central nervous system (CNS) and the peripheral nervous system (PNS), shown in Figure 7. The CNS is comprised of the brain and spinal cord; the PNS connects the CNS to the rest of the body. In this section, we focus on the peripheral nervous system; later, we look at the brain and spinal cord.
Figure 7. The nervous system is divided into two major parts: (a) the Central Nervous System and (b) the Peripheral Nervous System.
The autonomic nervous system controls our internal organs and glands and is generally considered to be outside the realm of voluntary control. It can be further subdivided into the sympathetic and parasympathetic divisions (see Figure 8). The sympathetic nervous system is involved in preparing the body for stress-related activities; the parasympathetic nervous system is associated with returning the body to routine, day-to-day operations. The two systems have complementary functions, operating in tandem to maintain the body’s homeostasis. Homeostasis is a state of equilibrium, in which biological conditions (such as body temperature) are maintained at optimal levels.
Figure 8. The sympathetic and parasympathetic divisions of the autonomic nervous system have the opposite effects on various systems.
Parts of the Nervous System by Rajiv Jhangiani, Ph.D. is licensed under a Creative Commons Attribution 4.0 International License, except where otherwise noted.

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Retrieved Text: Before diving into ANS anatomy and physiology, it is important to have a general understanding of its location within the Nervous system as a whole. The image below displays this quite well.
We can see that the autonomic nervous system is a component of the peripheral nervous system, and that it belongs specifically to the motor division of the PNS.
This can be a bit confusing, because we tend to associate everything involving the body’s viscera (organs) with the ANS, including sensory information from the viscera (upset stomach, etc). This is not the case however. The Autonomic Nervous system is solely responsible for the innervation of smooth muscle, cardiac muscle, and glands. For this reason, it is strictly a motor arm of the peripheral nervous system. Sensory information travels to the spinal cord from the viscera along visceral sensory fibers that are separate from the ANS.
So, knowing what the ANS innervates (knowing what its effectors are) we can make a fairly educated guess about what its roles are. Knowing that it innervates smooth muscle, we can surmise that it plays a role in gastric motility, artery vasoconstriction/dilation, gland secretions, heart rate, and bronchiole constriction/dilation, among other things involving smooth muscle, cardiac muscle, and glands. These guesses are correct! The ANS helps maintain many internal functions including those listed above. Rather than list all of the ANS’s functions as a whole, lets take a look at the two divisions of the ANS and their functions.
Most organs of the body have dual innervation. This means that they are innervated by

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Retrieved Text: Neuropathy is damage or disease which affects nerves in the body. To understand neuropathy, one must understand how the nervous system works. The nervous system is comprised of two parts: the peripheral nervous system, which connects the nerves running from the brain and spinal cord to the rest of the body (from eyes, mouth, arms and hands to internal organs, to legs and feet) and the central nervous system, which includes the brain and spinal cord. Neuropathy, also referred to as peripheral neuropathy, occurs when there is damage to the nerves, inhibiting them from sending messages from the brain and spinal cord to the other parts of the body. At Regenerative Medical Center of Delaware, we offer both pain management and regenerative cellular therapies to not only treat your neuropathy symptoms but to heal the root cause.
Are You Experiencing These Common Neuropathy Symptoms?
Regenerative medicine is a natural safe and effective alternative to traditional treatments for neuropathy. Unlike traditional approaches including the use of opioids, costly therapies and painful surgeries, regenerative medicine offers effective treatment options with little to no risk or side effects. Stem celltreatments target the damaged nerves affected by neuropathy, which relieves chronic pain. Stem cells have the unique ability to replicate and create new, healthy cells, while repairing damaged tissue. The best stem cells to use for neuropathy are fat derived, embryonic, or bone marrow.
Contact Regenerative Medical Center of Delaware today to discuss whetherour pain management and regenerative medical therapies are right for you to help with your neuropathy symptoms.We look forward to

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Retrieved Text: Download Color Atlas And Textbook Of Human Anatomy Nervous System And Sensory Organs written by Werner Kahle and has been published by Thieme this book supported file pdf, txt, epub, kindle and other format this book has been release on 2003 with Medical categories.... Download Color Atlas And Textbook Of Human Anatomy Nervous System And Sensory Organs written by Werner Kahle and has been published by Thieme this book supported file pdf, txt, epub, kindle and other format this book has been release on 2003 with Medical categories.
Central And Peripheral Nervous System Study Guide [Free Download] Central And Peripheral Nervous System Study Guide [PDF] [EPUB]. Book file PDF easily for everyone and every device.

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Retrieved Text: Sensory afferent division The sensory also known as afferent division of the nervous system contains nerves that come from the viscera internal organs and the somatic areas muscles, tendons, ligaments, ears, eyes and skin. The first function is the gathering of information from the sensory receptors that monitor changes occurring internally and externally of the body. When a second messenger system is activated, it starts a cascade of molecular interactions inside the target cell, which may ultimately produce a wide variety of complex effects, such as increasing or decreasing the sensitivity of the cell to stimuli, or even altering. The peripheral nervous system consists of sensory neurons, ganglia clusters of neurons and nerves that connect to one another and to the central nervous system. Many types of neuron possess an , a protoplasmic protrusion that can extend to distant parts of the body and make thousands of synaptic contacts; axons typically extend throughout the body in bundles called nerves.
The trajectory of the ball and its speed will need to be considered. The four primary functions of the nervous system are the sensory, communicative, integrative and motor functions. All cells of the nervous system are made of neurons. Visit the Nobel Prize to play an interactive game that demonstrates the use of this technology and compares it with other types of imaging technologies. This reflex functions to protect us from injury. Nerves are large enough to have been recognized by the ancient Egyptians, Greeks, and Romans, but their internal structure was not understood until it became possible

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Retrieved Text: How is nervous system working? It functions by sending electrical impulses across a specialized group of cells called neurons. Learn the whole process here.
The nervous system is a complex network of interconnected excitable cells. These cells, called neurons, are capable of transmitting an electrochemical signal when appropriately stimulated. Normally, a slight negative electrical potential is maintained in the neurons (relative to the outside) and this is momentarily reversed during transmission of nerve impulse.
Activation of neuron cell and generation of a nerve impulse that moves forward from its point of origin is known as action potential. As already mentioned, the inside of a neuron is slightly electrically negative. Moreover, the inside of the neuron is relatively deficient in sodium ions (positively charged) and relatively rich in potassium ions (also positively charged). Normally, the neuron cell membrane is not permeable to these sodium and potassium ions. However, there are specialized channels that open up during action potential and allow for the movement of such ions. When an action potential is initiated, sodium channels open first and this causes entry of sodium into the neuron cell and now the inside of the neuron becomes relatively positive. After this, the potassium channels open up and the potassium from inside of neuron moves out, and the inside of the cell again becomes negative. All the nerve impulses are propagated in the form of this electrical activity caused by an action potential.
Neurons are interconnected with each other at specialized junctions called the synapses. Electrical impulse travelling in a neuron is transferred to

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Retrieved Text: The nervous system is the part of an animal that coordinates its actions by transmitting signals to and from different parts of its body. The basic unit of the nervous system is a neuron. The structures of the nervous system are described in terms of two principal divisions-the central nervous system CNS and the peripheral nervous system PNS. Identify the basic parts of a neuron.
Psychologists striving to understand the human mind may study the nervous system. This helps prevent a Trojan horse program or other types of malicious code from stealing the user's Windows credentials. In vertebrates it consists of two main parts, the central nervous system CNS and the peripheral nervous system PNS. What are the two major groups of nervous system organs.
Receptors Receptors are specialised nerve cells, which are adapted to respond to a stimulus. Flip the cube upside down so that white is on top. Describe how neurons communicate with each other. The PNS cranial and spinal nerves and ganglia provides the communication lines between the CNS and the body's muscles, glands, and sensory receptors. The stimulants mimic neurotransmitters in action. Explain how drugs act as agonists or antagonists for a given neurotransmitter system. The stimulation of rods or cones generates a nerve impulse.

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Retrieved Text: Every species within the animal kingdom, contains the Endocannabinoid System (ECS), except for insects.
The ECS was named after cannabinoids, which are found abundantly in cannabis as well produced naturally within the human body.
Research conducted on cannabinoids such as THC, CBD, CBG and CBC that are produced by cannabis lead to the discovery of the Endocannabinoid System (ECS).
Think of receptors as locks and cannabinoids as the keys: when the right key ‘cannabinoid’ finds the matching lock ‘receptor,’ it opens the door and delivers a message.
Cannabinoids either bind or block specific receptors in our bodies, thus altering messages being sent through the central and peripheral nervous system.
The best way of releasing cannabinoids in cannabis is to do so by heating the matter in order to make the trichomes, which contain the terpenes and cannabinoids, undergo a chemical change.
CB1 Receptors control neurons present in the central and peripheral nervous system, which include the brain and spinal cord, as well as some peripheral organs and tissues.
CB1 Receptors are not present in the medulla oblongata, which is the part of the brain stem responsible for respiratory and cardiovascular functions.
*There is no risk of an overdose with cannabis, as there is no chance of causing respiratory or cardiovascular failures.
CB2 Receptors are present in the peripheral nervous system, which are the nerves and ganglia existing outside of the brain and spinal cord. CB2 Receptors are also found profusely concentrated in the immune system, which is highly concentrated within the spleen and liver, as well as related to the reproduction of white blood cells.
Cannabis

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Retrieved Text: We are asked this question daily at the 4 offices of Virginia Family Chiropractic. Our doctors specialize in the treatment of different types of neuropathy and we literally have seen thousands of cases, because of our cutting-edge protocols in utilizing MLS laser and spinal decompression to successfully treat the right candidate.
But the problem in answering the question lies in the fact that “neuropathy” is a general term for pathology, irritation, compression, lack of blood flow, damage, deterioration, or any other disease of a nerve. It is commonly misunderstood to be a “specific” type of a nerve problem. But in reality there are dozens of different neuropathies that may occur within the body and each can be vastly different in presentation, causation, and treatment required.
First, let’s start with the basics. Our main nervous system is composed of our brain and spinal cord. This constitutes our “central” nervous system. The brain is the director and, obviously, the most important component of the entire system, as without it, we cannot function and we die. It is protected by our skull or cranium.
Our spinal cord is composed of a tightly wrapped bundle of thousands of individual spinal nerves that communicate and connect directly with the different parts of the brain and the rest of the body and organs. The spinal cord is contained within the bony vertebral column of the spine for protection from outside damage. We have 24 individual and moveable vertebrae, as well as, a block of bone at the bottom called the sacrum. This system allows for

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Retrieved Text: The sympathetic and parasympathetic divisions have both central and peripheral components. Clusters of nerve cells that contribute to the control of many organs via the ANS are located in the hypothalamus and brain stem (Fig. 2). Many of these clusters seem to be involved in regulating specific functions. For example, direct stimulation of certain areas can induce an increase in arterial blood pressure, whereas stimulation of other areas alters body temperature, gastrointestinal activity, and bladder function. To a great extent, these auto-nomic regions in the lower brain stem are influenced by neurons originating from cortical regions of the brain; thus, many human behavioral responses include auto-nomic responses that are mediated through the hypothalamus and reticular formation. Examples of such autonomic responses include increased gastric acid secretion upon the sight and smell of food and increased heart rate and dilatation of the pupils of the eye upon being frightened.
In contrast to the peripheral efferent component of the somatic nervous system, which consists only of the axons of spinal motor neurons, the peripheral efferent components (Figs. 1 and 3) of both the sympathetic and parasympathetic divisions of the ANS are rather complex, consisting of preganglionic axons, autonomic ganglia, and postganglionic neurons. The somata of efferent sympathetic preganglionic neurons are located in the intermediolateral horn of the spinal cord in regions from the first thoracic to the third or fourth lumbar segment (see Fig. 1). Axons of these preganglionic neurons leave the spinal cord and are traditionally thought to make synaptic contact with postsynaptic neurons located in either the

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Retrieved Text: Nervous tissue is a highly differentiated tissue composed of nerve cells, nerve fibers, dendrites, and neuroglia. It is composed of neurons, or nerve cells, which receive and transmit impulses, and neuroglia, also known as glial cells or more commonly as just glia (from the Greek, meaning glue), which assist the propagation of the nerve impulse as well as providing nutrients to the neuron.
There are several main components of our nervous system, and they are composed of nervous tissue. The word tissue tends to elicit the thought of wiping runny noses. But in terms of our body, tissue is defined as a group of cells with the same general functions forming organs and other body parts. Of the five main types of body tissue, nervous tissue is responsible for receiving, sending, and processing sensory input. In this lesson, learn about the components of nervous tissue and gain a better understanding of how it works for our body.
It is made up of different types of nerve cells, all of which have an axon, the long stem-like part of the cell that sends action potential signals to the next cell. Bundles of axons make up the nerves.
Nervous tissue makes up three major parts of our nervous system: nerves, the spinal cord and the brain. Our nervous system consists of two main parts: the peripheral and central nervous systems. The peripheral nervous system consists of the nerves that extend to all reaches of the body- the periphery. The central nervous system is made up of the spinal cord and brain

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Retrieved Text: Like other cells, each neuron has a cell body (or soma) that contains a nucleus, smooth and rough endoplasmic reticulum, Golgi apparatus, mitochondria, and other cellular components. Neurons also contain unique structures for receiving and sending the electrical signals that make communication between neurons possible ([link]). Dendrites are tree-like structures that extend away from the cell body to receive messages from other neurons at specialized junctions called synapses. Although some neurons do not have any dendrites, most have one or many dendrites.
Neurons contain organelles common to other cells, such as a nucleus and mitochondria. They also have more specialized structures, including dendrites and axons.
Neurogenesis At one time, scientists believed that people were born with all the neurons they would ever have. Research performed during the last few decades indicates that neurogenesis, the birth of new neurons, continues into adulthood. Neurogenesis was first discovered in songbirds that produce new neurons while learning songs. For mammals, new neurons also play an important role in learning: about 1,000 new neurons develop in the hippocampus (a brain structure involved in learning and memory) each day. While most of the new neurons will die, researchers found that an increase in the number of surviving new neurons in the hippocampus correlated with how well rats learned a new task. Interestingly, both exercise and some antidepressant medications also promote neurogenesis in the hippocampus. Stress has the opposite effect. While neurogenesis is quite limited compared to regeneration in other tissues, research in this area may lead to new treatments for disorders such as Alzheimer’s,

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Retrieved Text: Although the nervous system is very complex, there are only two main types of cells in nerve tissue. The actual nerve cell is the neuron. It is the "conducting" cell that transmits impulses and the structural unit of the nervous system. The other type of cell is neuroglia, or glial, cell. The word "neuroglia" means "nerve glue." These cells are nonconductive and provide a support system for the neurons. They are a special type of "connective tissue" for the nervous system.
Neurons, or nerve cells, carry out the functions of the nervous system by conducting nerve impulses. They are highly specialized and amitotic. This means that if a neuron is destroyed, it cannot be replaced because neurons do not go through mitosis. The image below illustrates the structure of a typical neuron.
Each neuron has three basic parts: cell body (soma), one or more dendrites, and a single axon.
In many ways, the cell body is similar to other types of cells. It has a nucleus with at least one nucleolus and contains many of the typical cytoplasmic organelles. It lacks centrioles, however. Because centrioles function in cell division, the fact that neurons lack these organelles is consistent with the amitotic nature of the cell.
Dendrites and axons are cytoplasmic extensions, or processes, that project from the cell body. They are sometimes referred to as fibers. Dendrites are usually, but not always, short and branching, which increases their surface area to receive signals from other neurons. The number of dendrites on a neuron varies. They are called afferent processes because

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Retrieved Text: The nerves outside of the brain and spinal cord are the peripheral nervous system. A problem with the nerves of the peripheral nervous system is called peripheral neuropathy or nerve palsy. Peripheral nerves connect your brain and spinal cord to your muscles and allow you to move your muscles. They also conduct feelings such as pain, temperature, touch, and limb position from the surface of your body to your brain. The nerves connecting to internal organs that allow involuntary actions such as breathing, sexual function, and digestion are also part of the peripheral nervous system.
a lack of vitamins or minerals.
The symptoms of peripheral neuropathy depend on which nerves are damaged and the function of the damaged nerves.
Nerves that help you move your muscles are called motor nerves. If motor nerves are damaged, you may have muscle weakness.
Nerves that conduct feelings, such as touch, are called sensory nerves. When these nerves are affected, you may have numbness, tingling, pain, or extreme sensitivity to touch.
The nerves connecting to internal organs are called the autonomic nervous system. Depending on what organs are affected, you may have vision problems, dizziness, problems with digestion, bloating, constipation, diarrhea, leaking of urine from the bladder, or incomplete bladder emptying.
Your health care provider will ask about your symptoms and medical history and will examine you. You may have a nerve conduction test to check the function of specific nerves. You may have other tests.
If the problem happens after you had a fall or something hit you, it usually goes away on its own and

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Retrieved Text: The autonomic nervous system (ANS) is composed of the sympathetic and parasympathetic divisions (Fig. 8.14). These two divisions have several features in common: (1) They function automatically and usually in an involuntary manner; (2) they innervate all internal organs; and (3) they utilize two motor neurons and one ganglion for each impulse. The first neuron has a cell body within the CNS and a preganglionic fiber. The second neuron has a cell body within the ganglion and a postganglionic fiber. Visceral reflex actions, such as those that regulate blood pressure and breathing rate, are especially important to maintenance of homeostasis. These reflexes begin when the sensory neurons in contact with internal organs send messages via spinal nerves to the CNS. They are completed when motor neurons within the autonomic system stimulate smooth muscle, cardiac muscle, or a gland. These structures are also effectors.
The sympathetic division is especially important during emergency situations when a person might be required to fight or take flight. It accelerates the heartbeat and dilates the bronchi-active muscles, after all, require a ready supply of glucose and oxygen. On the other hand, the sympathetic division inhibits the digestive tract-digestion is not an immediate necessity if you are under attack. The neurotransmitter released by the postganglionic axon is primarily norepinephrine (NE). The structure of NE is like that of epinephrine (adrenaline), an adrenal medulla hormone that usually increases heart rate and contractility.
The parasympathetic division, sometimes called the housekeeper division, promotes all the internal responses we associate with a relaxed state; for example, it causes

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Retrieved Text: Neurology treatment abroad can help you to locate specialist centres overseas. Neurology is the medical specialty that investigates, diagnoses and treats disorders of the nervous system. There are three areas that make up this area; these are the central, peripheral and autonomic nervous systems. The central nervous system encompasses the brain and spinal cord, the peripheral nervous system connects limbs and organs, and the autonomic nervous system encompasses senses and motor skills. This also includes their coverings, blood vessels, and all effector tissue (such as muscle).
Some of the more common conditions that impact on the nervous system are behavioural/cognitive syndromes, epilepsy, headache disorders (migraine, cluster headaches, tension headaches), traumatic brain injury, neurodegenerative and movement disorders (Alzheimer's, Parkinson's and Huntington's diseases), sleep disorders, cerebral palsy, multiple sclerosis, meningitis, spinal cord disorders (tumours, infections, trauma), as well as speech and language disorders.
The neurology treatment category includes imaging tools for diagnostics, such as computed tomography (CT), magnetic resonance imaging (MRI), and also a long list of treatments and neurosurgical procedures. For example, radiosurgery using a gamma knife is used for treating tumours, and endovascular surgery for the treatment of aneurysms. There is also the vagal nerve stimulator to treat epilepsy and ulnar nerve compression.
For a full list of available destinations for neurology treatment please see the search box to the right.

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Retrieved Text: Teach the parasympathetic nervous system in a new way!
Show how our parasympathetic nervous system works to control our fight or flight state.
The model covers the nerves and ganglia of the parasympathetic nervous system and shows the organs they innervate. A great way to learn and review this part of the peripheral nervous system.

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Retrieved Text: In general, homeostasis refers to the balance within a system that keeps it operating within a range of conditions. Homeostasis helps animals maintain stable internal and external environments with the best conditions for it to operate. It is a dynamic process that requires constant monitoring of all systems in the body to detect changes, and mechanisms that react to those changes and restore stability.
There are three components to homeostatic regulation in animals: the receptor, the control center, and the effector. Receptors are constantly surveilling conditions and detect changes that take conditions outside the normal range, away from a set point. The control centers receive and process the information from the receptors and give commands to the effectors on how to respond.
The failure of homeostatic regulation in just one body system will cause conditions to deteriorate and it may be fatal. For the health of an organism, all homeostatic regulation mechanisms must function properly. The information below describes how various body systems contribute to overall homeostasis.
The nervous system maintains homeostasis by controlling other parts of the body. It comprises the central nervous system and the peripheral nervous system. The peripheral nerves are those outside of the brain and spinal cord which go to the limbs and organs. The brain and spinal cord make up the central nervous system. The hypothalamus in the brain is particularly important for maintaining homeostasis because it controls the actions of the medulla oblongata (involuntary functions), the autonomic nervous system (smooth muscle and glands), and the pituitary gland (hormone excretion).
This system comprises the

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Retrieved Text: � Discuss how we know we feel something; use a question and asnswer method to discuss the role of the nervous system in the experience of being touched. Hand out human body outlines. Explain (20 minutes) � Explain motor and sensory nerves, central and peripheral nervous system. Hang the tracing and have volunteers add central and then peripheral nervous systems to a large outline of the red hat system administration i rh124 pdf 5) The autonomic nervous system may cause activation or inhibition, depending on the division that is active and the target that is affected. 8) Thermoregulatory responses to increased heat are mediated by the sympathetic nervous division.
Diseases of the parasympathetic or sympathetic divisions of the AUTONOMIC NERVOUS SYSTEM; which has components located in the CENTRAL NERVOUS SYSTEM and PERIPHERAL NERVOUS SYSTEM.
5) The autonomic nervous system may cause activation or inhibition, depending on the division that is active and the target that is affected. 8) Thermoregulatory responses to increased heat are mediated by the sympathetic nervous division.

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Retrieved Text: Sensergetics is unique in its adaptation of methodologies, combining holistic healing techniques based in Chinese medicine, kinesiology, chiropractics and neuro-therapeutic techniques to facilitate balance and assess nutrition and other substances that may affect the energy anatomy.
In Sensergetics an imbalance is referred to as a disturbance within your subtle energy anatomy when it is exposed to a particular substance. A disruption of the natural balance within these previously synchronised processes may cause a change in the electromagnetic field in various parts of the body. This is why the treatment protocols are aimed at the energetic and neurological discrepancy which may either contribute to or allow the condition to exist, and not at the condition itself.
Growing numbers are embracing a relatively new modality called Sensergetics, developed by complementary medicine practitioner Lyn Treloar.
Australians now spend over one billion annually on natural therapies. Of these natural therapies, Kinesiology, now practised in over 104 countries, has experienced one of the most rapid growths and has recently been classified by the Australian National Training Association as a complementary medicine. As a result some of Australia’s major health funds are now including Kinesiology in their rebate schemes and Sensergetics falls under this category.
In the 1970s American chiropractor Dr George Goodheart developed Applied Kinesiology. Goodheart incorporated reflex points from both osteopathy and chiropractics and embraced techniques derived from Chinese medicine using acupressure and the five element theory of the meridian system – the framework of many kinesiology modalities today. In terms of its dual East-West roots, Kinesiology actually goes back thousands of years.
Today Sensergetics

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Retrieved Text: Definition (MSH) The craniosacral division of the autonomic nervous system. The cell bodies of the parasympathetic preganglionic fibers are in brain stem nuclei and in the sacral spinal cord. They synapse in cranial autonomic ganglia or in terminal ganglia near target organs. The parasympathetic nervous system generally acts to conserve resources and restore homeostasis, often with effects reciprocal to the sympathetic nervous system.
Definition (CSP) craniosacral division of the autonomic nervous system; generally acts to conserve resources and restore homeostasis, often with effects reciprocal to the sympathetic nervous system; cell bodies of the parasympathetic preganglionic fibers are in brain stem nuclei and in the sacral spinal cord; they synapse in cranial autonomic ganglia or in terminal ganglia near target organs.

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Retrieved Text: Chiropractic is about helping people live healthier, fuller lives. Chiropractors focus on the nervous system and painlessly, manually adjust the vertebral column to affect the nervous system. According to Gray’s Anatomy , the nervous system is the master system in the body which controls and coordinates all other systems such as respiratory, digestive, muscular, and immune.
The nervous system includes the brain, spinal cord, the spinal nerves that exit the vertebral column through openings on the side of each vertebra, and all the peripheral nerves that branch off to serve organs, tissues, blood vessels and muscles. Information from the environment, both external and internal, goes through the spine to get to the brain. In the same manner, information and decisions made in the brain go through the spine to affect certain outcomes. It is a two-way flow of information.
The chiropractic adjustment is intended to remove any disruptions or distortions of this energy flow that may be caused by slight vertebral misalignment’s called subluxations. Chiropractors are trained to locate these subluxations and then to remove them to restore the normal flow of nerve energy, in terms of both quality and quantity.
The idea is that if the master system (the nervous system) is healthy and functioning well, then other systems under its control will also function in a more optimal fashion. Chiropractic is based on the belief that the same innate intelligence that can grow a single cell into a complex human being, made of billions of cells, can also heal the body if it is free of disturbances

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Input Text: Answer the following question given this paragraph: 

Figure 18.12 The northern spotted owl and the Mexican spotted owl inhabit geographically separate locations with different climates and ecosystems. The owl is an example of allopatric speciation. (credit "northern spotted owl": modification of work by John and Karen Hollingsworth; credit "Mexican spotted owl": modification of work by Bill Radke).


Q: The northern spotted owl and the mexican spotted owl inhabit geographically separate locations with different climates and ecosystems. the owl is an example of?

 Choices:

- parallel evolution

- symbiotic species

- allopatric speciation

- biodiversity

A:

Target Text: allopatric speciation

#### Retrieved Documents ####

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Retrieved Text: New U.S. Geological Survey (USGS) science reaffirms, with strong genetic evidence, that the northern spotted owl is a separate subspecies from California and Mexican spotted owls. The same study also found no significant genetic differences between Mexican and California spotted owls.
The study also confirms a zone of mixing between northern and California spotted owls in the Klamath region of southern Oregon, indicating a more northerly presence of California spotted owls than previously thought.
Researchers found no evidence, however, for the presence of northern spotted owls in the traditional range of the California spotted owl.
The U.S. Fish and Wildlife Service has provided the findings to its contractor, Sustainable Ecosystems Incorporated, which is reviewing the scientific information concerning the northern spotted owl. The findings will be among the information the Service considers during its five-year review of the owl.
Susan Haig, a conservation geneticist with the USGS Forest and Rangeland Ecosystem Science Center in Corvallis, Ore., will present these findings at a meeting of the Northern Spotted Owl Review Team in Portland, Ore., on May 13, 2004.
"This is the most extensive, detailed treatment of the genetics of the spotted owl to date and covers all three subspecies in great detail," said Haig. "These findings raise questions about range delineations for northern, California, and Mexican spotted owls. The information can be used with population estimates, assessments of habitat fragmentation, and other factors to address the status and recovery efforts for spotted owls."
Spotted owls are mostly non-migratory, long-lived, socially monogamous birds whose populations have declined in old forests of western North America.

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Retrieved Text: The researchers further found no statistically significant genetic differences between the northern and Mexican spotted owls .
Special construction requirements were developed to minimize repercussions on threatened species, including the Mexican spotted owl, desert tortoise, lesser long-nosed bat, and long-tongued bat.
The Mexican spotted owl was listed as threatened in 1993 due to the historical alteration of its habitat and the danger of catastrophic wildfire.
It applies to Utah, Colorado, Arizona, and New Mexico, where most of the United States' roughly 2,000 Mexican spotted owl pairs reside.
Since I like stacked decks, my additional interest was in yet another forest visitor, recently found foraging here--the Mexican spotted owl, freshly listed as an Endangered Species.
Critical Habitat for the Mexican Spotted Owl (Strix occidentalis lucida) A July 21 proposal would designate nearly 13.
Specifically, residents near the release site in Kane County blame the decline of the timber industry in southern Utah and northern Arizona on federal rules protecting the Mexican spotted owl and the northern goshawk, he said.
The recovery plan for the threatened Mexican spotted owl (Strix occidentalis lucida) was published in 1995.
He blamed the decline of the logging industry in southern Utah and northern Arizona on federal rules protecting the Mexican spotted owl and northern goshawk, and does not want another rare bird adding to the problems.
Habitat management for the threatened Mexican spotted owl (Strix occidentalis lucida) will also promote conservation of Goodding's onion in areas where these species overlap.
Today, trained Apache youth work as field technicians to find Mexican spotted owl (Strix occidentalis lucida) locations, not to trick or steal

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Retrieved Text: Barred Owl (length 53.5 cm) is a large, yellow-billed and dark-eyed owl that lacks ear tufts. It has a barred breast and vertical streaks below. The plumage of both sexes is alike. The Mexican subspecies Strix varia sartorii, known from at least 10 Mexican states, inhabits humid to drier montane forests. It is found along both slopes from central to southern Mexico at elevations of 1500 to 2500 m. In all likelihood, it is a different species than the widespread northern form in Canada and the United States. Barred Owl is about 5 cm longer than the Spotted Owl with which it may occur—the more so as its range expands in certain locations. In pine-oak and conifer forests where they overlap, the larger Barred Owl may be competitively superior. Vocalizations of Barred Owls living in central Mexico are poorly documented; no recordings are available on either of the large online depositories of bird vocalizations. Those included here are from the northern subspecies group. Additionally, the southern limits of this form (or species) are in dispute as some authors lump it with the similar Fulvous Owl.

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Retrieved Text: We estimated diet composition of sympatric Mexican spotted (Strix occidentalis lucida, n = 7 pairs of owls) and great horned owls (Bubo virginianus, n = 4 pairs) in ponderosa pine (Pinus ponderosa) - Gambel oak (Quercus gambelii) forest, northern Arizona. Both species preyed on mammals, birds, and insects; great horned owls also ate lizards. Mammals dominated the diet of both species.
We summarized existing knowledge on winter movements and range and habitat use of radio-marked Mexican spotted owls. In light of that information, we evaluated the adequacy of current management guidelines. Seasonal movement or "migration" appears to be a regular feature of the winter ecology of Mexican spotted owls.
The Spotted Owl (Strix occidentalis) is most common in mature and old-growth coniferous forests throughout much of its range (Forsman et al. 1984, Laymon 1988, Ganey and Balda 1989a, Thomas et al. 1990). Proximate factors underlying habitat selection in Spotted Owls are understood poorly.
The Mexican spotted owl (Strix occidentalis lucida) was listed as a threatened species under the Endangered Species Act (ESA) in April 1993 (USDI 1993). Concomitant with the listing of the owl, a recovery team was appointed to develop a plan to recover the owl, allowing for its removal from the list of threatened and endangered species. The recovery plan - "the plan" - was completed and accepted by the U.S.
I studied the calling behavior of radio-tagged Mexican Spotted Owls (Strix occidentalis lucida) in northern Arizona. Owls used a variety of calls, with three call types (Four-note Location Call, Contact Call, and Bark Series) accounting for 86%

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Retrieved Text: The Who’s Who of Owls: The North American Spotted Owl.
Owls belong to a group of birds that includes about 205 species. They are known for their distinct calls, nocturnal habits, and silent flight, and are sorted into two basic groups—barn owls and true owls. Barn owls have a heart-shaped face, long legs and powerful talons. True owls are more diverse, lacking the heart-shaped face, and include screech owls, horned owls and the Northern Spotted Owl.
Owls are predators and feed on small mammals such as mice, squirrels, voles and rabbits. They cannot chew their prey since, like all birds, they do not have teeth. Instead, they swallow small prey whole or use their sharp bill to tear their food into small pieces before swallowing. They later regurgitate pellets of indigestible material such as bone, fur and feathers. Most owls are nocturnal and hunt at night, avoiding competition with daytime avian hunters such as hawks and eagles.
Possibly the most fascinating characteristic of owls is their adaptation of special flight feathers for silent flight. Downy feathers cover the surfaces of the wing which enable them to minimize the sound made when flapping their wings. Owls also have an acute sense of hearing that helps them locate and capture prey. In some species, the ears are located asymmetrically to enhance their ability to pinpoint the origin of the sounds they hear by sensing the minute difference in the time that sound reaches each ear. These characteristics make owls silent and deadly predators.
The Northern Spotted Owl: Strix occidentalis, is a nocturnal

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Retrieved Text: WFLC is monitoring Washington State’s Northern Spotted Owl Policy Working Group that was formed as a result of settlement in Seattle Audubon Society v. Sutherland. Learn more.
Carpenters Industrial Council v. Salazar challenges the federal government’s final northern spotted owl recovery plan and the final revised designation of critical habitat for the northern spotted owl.
Seattle Audubon Society v. Sutherland challenged Weyerhaeuser to stop logging critical northern spotted owl habitat in Washington State.
Seattle Audubon Society v. Norton challenged the failure of the U.S. Fish & Wildlife Service to develop and implement a northern spotted owl recovery plan.

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Retrieved Text: 3.3 Is the EA 18G Growler Jet Substantially Different from the F18 Hornet Jet?
This category contains research articles on spotted owl population declines, growler jet noise, legal filings and other issues.
For the record, this is my public comment regarding the US Navy's application for a Special Use Permit to expand their use of US Forest Service lands beginning in 2015. As described in the Navy's Environmental Assessment, submitted in September 2014, the US Navy's proposed expansion includes allowing three “mobile electromagnetic radiation emitters” to be moved around between 12 different locations on US Forest Service land (and 3 locations on Washington State Department of Natural Resources land) where the mobile transmitters will “interact” with up to 135 “US Navy F18 Growler military jets” for 12 to 16 hours per day for 260 days per year for the next 10 to 20 years. The Forest Service land that the US Navy is requesting a Special Use Permit to use is on or near Critical Habitat for endangered species, included the Northern Spotted Owls and Marbled Murrelets. The US Navy claims in their Environmental Assessment that these electronic warfare games, which would include more than 22,000 “fly overs” of critical habitat for these endangered species per year, “may affect, but would not adversely affect” these endangered species. However, because the US Forest Service is under a binding 1994 Record of Decision (1994 ROD) to affirmatively protect these endangered species and their critical habitat, the US Forest Service is required to independently and accurately determine whether granting a Special

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Retrieved Text: As you can imagine, operating in one of the last stands of old-growth forest in the Whistler Valley means we encounter and (respectfully) operate side-by-side some incredible wildlife. In this feature we'd like to introduce you to the northern spotted owl.
This owl loves to live in old-growth forest with high tree canopies so it can fly between and underneath the trees. Standing snags (trees with snapped-off tops) make perfect nesting sights for this bird as do big trees with large holes. Northern spotted owls live in pairs, with only 100 pairs thought to be left in BC you can count yourself very lucky if you see one.
You'll know it's a northern spotted owl by it's medium size, dark brown colour with round white spots and facial discs with dark borders. You may also identify it by it's territorial call "whoop wu-hu-hoo" or by it's recognizable flight pattern of fast paced wingbeats between stretches of gliding.
In the last decade the province has protected over 182,000 hectares of their habitat in an effort to preserve and encourage growth in the population. Outside of BC they can also be found down the west coast in Washington, Oregon and northern California.
Nocturnal hunters, they feed mostly on small rodents but can also prey on birds, reptiles and invertebrates. Their lifespan is approximately 10 years long and they reproduce in the late winter/early spring. The female northern spotted owl lays 2-3 eggs per clutch. A week or so after hatching the male owl takes over feeding duties and hunts for the hatchlings.

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Retrieved Text: You are here: Home » News » Northern Spotted Owl » Seattle Times: "Groups challenge plan for spotted-owl recovery"
GRANTS PASS, Ore. — Conservation groups are suing the Bush administration to undo the northern-spotted-owl recovery plan that is making it possible to ramp up old-growth- forest logging in Oregon.
A coalition of conservation groups filed motions Monday to intervene in a timber-industry lawsuit over the owl in U.S. District Court in Washington, D.C.
Seattle Audubon Society and the others argue the U.S. Fish and Wildlife Service was politically influenced by the Bush administration and violated the Endangered Species Act by ignoring the best available science, both in the plan for saving the owl from extinction and in deciding to reduce protections for old-growth forests where the owl lives by 1.6 million acres.
The owl-recovery plan twice flunked peer reviews by outside scientists who said it contained no scientific basis for allowing more logging of the old-growth forests set aside under the Northwest Forest Plan as habitat for the owl. The plan also identified wildfire and the invasion of spotted-owl territory by the barred owl as factors. .
Dominick DellaSala of the National Center for Conservation Science & Policy, a plaintiff in the lawsuit, served on a team of scientists who worked on the owl-recovery plan before it was taken over by the Fish and Wildlife Service.
He said they were prevented from doing their jobs by a group of Bush administration officials in Washington, who needed an owl-recovery plan that would allow logging in old-growth forests in order to push through the

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Retrieved Text: The Northern Spotted Owls are disappearing from Oregon’s forests.
Twenty years after the landmark ruling that eliminated logging on millions of acres of National Forest in order to preserve habitat of the endangered Northern Spotted Owl, those same Spotted Owls are now critically threatened by, of all things, other owls.
In conjunction with historic and ongoing habitat loss, Barred Owls now represent the most critical threat to the survival of the Northern Spotted Owl.
Concerned that the Spotted Owl is likely to go extinct in substantial parts of its historic range without managing Barred Owl populations, the U.S. Fish and Wildlife Service recently released a draft Environmental Impact Statement (EIS) on “experimental removal” of encroaching Barred Owls. The draft EIS outlines eight potential courses of action (including one option to take no action) varying by location, duration, removal method, and cost. However, most of the options involve killing Barreds.
The thing is, no matter how ardently the Fish and Wildlife Service strives to present its studies and policy options in the most objective of ways, killing owls is an ethical issue that Oregonians will have to digest according to their individually subjective values.
For example, should we simply throw up our hands and see what happens between the two owls—let nature take its course? Or is it our responsibility to attempt to manage and mitigate the situation? Is it acceptable to kill Barred Owls if, indeed, they were able to invade Spotted Owl territory because of human-influenced land changes, as many believe? Would it be acceptable to kill them if they

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Retrieved Text: With full-color photographs and illustrations throughout, this book explains how to identify, care for, and raise butterflies in your own backyard, whether you live in an urban or rural setting. 176 pages, paperback.
Provides up to date information on the 18 species of owls found in the United States and Canada. Includes detailed descriptions, habits, and range maps. Illustrated with color plates and black & white photographs. 208 pages, soft cover.
Contains 150 color photos of birds, nest boxes, nestlings, and eggs. This book will help you discover the fascination and importance of nest box monitoring.
This book contains species-appropriate nestbox designs for North America's most fascinating cavity-nesting birds. Full Color photographs and illustrations. 216 pages, paperback.
Full color illustrations of the following species: Great Gray Owl, Northern Hawk Owl, Northern Pygmy Owl, Northern Saw Whet Owl, Shorteared Owl, Snowy Owl, Spotted Owl, and Western Screech Owl. Chart measures 24" x 36".
Illustrates 13 species. The Bald Eagle,Red-tailed Hawk, Sharp-shinned Hawk, Coopers Hawk, American Kestrel and other popular hawks are included in this identification chart. Chart measures 24" x 36".
Illustrates 12 species including the Golden Eagle, Peregrine Falcon, Northern Goshawk, Merlin, Osprey, and Marsh Hawk. Chart measures 24" x 36".
This masterful print depicts all the official state birds of the U.S. in high detail. Scientifically accurate and a great educational tool. Chart measures 24" x 36".

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Retrieved Text: Normally it would be very difficult to get a picture of a Barred Owl. However, I was able to photograph this beauty up close because he is in his own private refuge shelter at Chickasaw State Park. Due to an injury that has rendered him blind in one eye, he will live the rest of his life under the care and protection of the park. He was actually very fortunate that they found him.
Owls rely on their sight, as well as their hearing, to hunt. Without his eyesight, he would most likely become prey himself, even if he survived the initial injury.
He is quite a beautiful owl even with his obvious eye injury.
Vocal Owls often referred to as "hoot owls"
Lives in the woods, nests in trees. Has been known to take over abandoned hawk or crow nests.
Eats frankly anything smaller than itself. Rodents, birds, amphibians, reptiles, and invertebrates.
Body Length: Up to 20"
For nearly 50 years, humans have laid the blame of the reduced Spotted Owl species (not classified as endangered) at the talons of the Barred Owl. There are several "experiments" taking place now to see if the Barred Owl is killed in certain areas IF the Spotted Owl will return and survive there.
A couple of things to keep in mind as you ponder this "experiment". The Barred Owl is killed by the Great Horned Owl in nature. The Barred Owl is the medium sized owl with the Spotted Owl being smaller and the Great Horned Owl being larger.
Also, all wildlife is being forced to move

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Retrieved Text: Jeffers encapsulated the idea that evolutionary processes shape all plants and animals. Unfortunately, far too many in the Forest Service and the collaboratives that work with them fail to understand this basic idea—a “healthy” forest is one with many sources of mortality. Chainsaws are no substitute for natural processes.
Recently on a collaborative/forest service field tour, participants were shown some fir trees with root rot. The group was told that the forest was “too dense” and thus the trees had become susceptible to root rot. The solution, of course, was to log (read kill) the fir trees so they would not succumb to root rot and die.
When I asked the collaborative members and agency personal assembled, “What was the ecological role of root rot in the ecosystem?”, I got perplexed blank stares.
It appeared that no one had ever considered such a question. Yet here they were anxious to log the forest based on the assumption that root rot killing trees was something to control or remove from the forest ecosystem.
Among the ecological values that root rot may provide to the forest ecosystem is a natural thinning of trees (unlike logging/thinning that lost money, root rot does this at no cost to taxpayers). Root rot selects for those trees less adapted to current and future climatic conditions, plus creates snags and dead wood that is critical to many wildlife species. The snags store carbon, and when trees fall over, they establish hummocky mounds that result in micro-sites for plants and animals.
The issue of root rot is a good

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Retrieved Text: The Spotted Owl is a resident species of owl found in western North America. This species will build nests in tree holes, crevices between rocks, or abandoned nests from other birds. The Spotted Owl sits on tree perches and swoops to the forest floor to dine on small rodents, frogs or small invertebrates and mammals. Its preferred habitat includes dense mixed woodlands, but usually lives on the edges of the forest to reach nearby fresh water supplies easily. This species is subject to deterioration due to destruction of its habitat throughout British Columbia and Washington in the United States. The conservation rating of this bird is Near Threatened.
Four note location calls from pair, "hoo, hoo-hoo, hoo".
"Who-cooks-for-you" and "who-who, who-cooks-for-you" calls between a pair.
The Spotted Owl was reported in 1860 by Hungarian immigrant John Xántus de Vesey. Other names include Canyon Owl, Brown-eyed Owl, Wood Owl, Pootie Owl and Hoot Owl.
Unlike most owls, they may not defend their eggs and young from predators, instead watching from nearby as the nest is destroyed.

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Retrieved Text: Over a hundred bird watchers traveled to Zwolle, because a very rare hawk owl was spotted Sunday evening. People came all the way from New Zealand to catch a glimpse of the bird.The approximately 40 centimeters large hawk was spotted at a gas station on the IJsselallee in Zwolle. The native species was only seen three time in the last hundred years. The first time, in 1920, he was found dead. The second time, in 1995 in Limburg, and the third time, in 2005 in Drenthe, he was photographed.
The rumors started earlier this month. A train driver saw a bird "size wood pigeon" sitting on the wire for a while, when he stopped between Zwolle and Leeuwarden.
The owl breeds in the vast, remote forests of northern Europe, Asia and North America. Researchers have no idea how many there are. Therefore, the hawk remains somewhat mystical for birdwatchers. Even if one is spotted in Scandinavia some Dutch birdwatchers will jump in their cars to catch a glimpse of the black-brown owl with white cross marks.
For those who want to see the hawk with his own eyes: the bird has not yet left. For now pictures and posts keep pouring in on Waarneming.nl and Twitter..

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Retrieved Text: Protecting endangered and threatened species.
Listed under the Endangered Species Act since 1992, Marbled Murrelets are primarily threatened by logging. The logging of mature- and old-growth coastal forests has resulted in the destruction and fragmentation of the species' nesting habitat. The Audubon Society of Portland uses a suite of tools to protect this rare seabird, including litigation, habitat restoration and advocacy.
There is probably no species more closely associated with our majestic ancient forests than the Northern Spotted Owl. However, unsustainable logging practices used throughout the last century have left only remnants of our old growth ecosystems, and the spotted owl now perches on the edge of extinction.
Portland will have an important role to play in recovering the Streaked Horned Lark, which was listed as threatened under the Endangered Species Act in fall 2013.
Many seabird species depend on forage fish like sardines for food, and the Audubon Society of Portland is working to keep this vital resource from being depleted. Studies show that when fisheries remove more than two-thirds of the maximum prey biomass of forage fish, seabird colonies’ productivity falters and even fails - these fish are a key food for growing chicks. Our goal: protect one third of forage fish for the birds.
Peregrine Falcons, once one of the most endangered species on earth, have been making a phenomenal comeback since 1972. The Audubon Society of Portland has worked since 1994 to develop a program to provide monitoring, research, management and educational outreach for the growing population of Peregrines nesting in downtown Portland.

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Retrieved Text: Spotted Owl In Ancient Forest by Nick Gustafson - 8" x 10"
Spotted Owl In Ancient Forest poster by Nick Gustafson. Our posters are produced on acid-free papers using archival inks to guarantee that they last a lifetime without fading or loss of color. All posters include a 1" white border around the image to allow for future framing and matting, if desired.
Wow! I know that took some work. Great job!
Nick this is a great owl painting. One of my favorite Birds!
An endangered spotted owl in an ancient forest.

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Retrieved Text: Significant numbers of owls are being illegally trapped and sacrificed each year in India to supply rituals and ceremonies marking annual Diwali celebrations. While the exact number of owls traded domestically is unknown, estimates place the figure in the thousands.
TRAFFIC has issued an advisory to enforcement agencies calling for increased efforts to help curb the trafficking and sacrifice of owls that peaks around the annual Diwali “Festival of Lights” celebrations.
People gather for Diwali festivities in Assi Ghat, India. Of course, there are many elements of Diwali that do not involve animal sacrifice. Image credit Kristian Niemi, CC BY-SA 3.0.
The document is based on TRAFFIC’s investigations into the illegal owl trade in India, published in Imperiled Custodians of the Night. The investigation found that owls are consumed and traded for a wide variety of purposes, including for magic, street performances, taxidermy, private aviaries/zoos, food, use in folk medicines, capturing other birds, use of claws and feathers in making headgear, and eggs used in gambling.
Illegal trapping and trade peaks around the Diwali festival month, especially in Northern India. Occult practitioners drive consumer demand by touting the use of owl parts for purposes ranging from curing various illnesses to fighting the effects of evil spirits. Birds are poached for their bones, talons, skulls, feathers, meat and blood, which are then used in talismans, magic rituals, and traditional medicine.
Owls, especially with “ears” (or tufts) are thought to possess greatest magical powers, and Diwali is claimed to be the most auspicious time for making owl sacrifices.
A barn owl, seen here in

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Retrieved Text: "I see the spotted owl as a kind of hapless symbol of what we have to do to preserve a huge and very important ecosystem - the North American temperate rain forests. We go around to international congresses, telling others to stop cutting down their rain forests, when we are, in fact, much closer to cutting down the last remaining old-growth rain forests on our own continent.
The spotted owl needs large tract of unbroken forest to survive. When these tracts are sliced up by logging operations, others predators come in. The spotted owl cannot stand the competition and becomes extinct in that area.
Mossy Branches - Spotted Owl by Robert Bateman is available as a signed and numbered limited edition print with a 14-3/4 x 18-5/8 image size priced at $625. LAST ONE! Order yours today. All artwork is professionally boxed and insured and guaranteed to arrive in mint condition.

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Retrieved Text: After all the ruffled feathers over saving the Northern spotted owl, the disagreeing sides are coming to a peaceful agreement. At least temporarily. This week, the state’s Forest Practices Board approved the formation of a working group to wrestle with matter of how to increase the Northwest’s owl numbers.
The owls — which have been protected under the Endangered Species Act since 1990 — have seen their numbers slip, rather than rebound. In 2006, environmentalists sued to stop logging on 50,000 acres of private timberland to protect the birds. As their settlement, this working group was formed and everyone promised to hold off on lawsuits for three years.
The group will have at least 11 members, including four enviros, four timber folks and three representatives of state government. They’re supposed to have recommendations completed by November 2009.
Discussion of the role of barred owls, a larger more aggressive competitor, suspected of driving out spotted owls. More information is needed, but even Shawn Cantrell, executive director of Seattle Audubon, said his group is willing to talk about trapping and/or killing the invading barred owls.
What to do about “owl circles” — the protected habitat around known nesting sites.

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Retrieved Text: All the Shasta Land Management foresters are experienced in preparing NEPA and CEQA documents. We have prepared many NEPA and CEQA documents for development projects such as resort expansion, hydroelectric projects, road construction, timber sales, and subdivisions. Our wildlife biologist has prepared many spotted owl surveys, sensitive species surveys, and biological evaluations for projects on National Forest land in relation to timber harvest, road construction, and mineral development.
The Shasta Land Management Consultants Wildlife Biologist has prepared many spotted owl surveys, sensitive species surveys, and biological evaluations for projects on National Forest land in relation to timber harvest, road construction, and mineral development.
Shasta Land Management Consultants offers Private Consulting Biologist (PCB) services. The California Department of Fish and Game (CDFG) recognizes PCBs as being qualified to evaluate potential impacts to the northern spotted owl per Board of Forestry Rules and the Federal Endangered Species Act and they have agreed to review and respond to PCB Consultation Worksheets within five working days of receipt. PCB Consultation Worksheets are equivalent to NSO Checklists ordinarily prepared by agency biologists; one of these forms must be submitted to CDF prior to approval of any THP in the range of the NSO. Persons in need of NSO consultations will realize significant time savings by retaining PCBs to prepare and submit the required documents.

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Retrieved Text: Sycamore Canyon is owned and managed by the Coronado National Forest, United States Forest Service. It is located near the town of Ruby, at the lower edge of Madrean evergreen oak woodlands while Sycamore Creek flows down to the Mexico border where it enters Sonoran desert-dominated habitat. The canyon is relatively shallow and narrow with intermittent drainage, and is very convoluted with scattered permanent pools. Vegetation is primarily high-elevation riparian, including Fremont cottonwood, willow, and velvet mesquite, with scattered Arizona sycamore.
This very small canyon has a very high concentration of nesting IBA priority bird species. According to the Arizona Breeding Bird Atlas (ABBA), 95 species of birds were either confirmed nesting or designated as probable or possible nesting species in or adjacent to Sycamore Canyon. This is one of the highest breeding bird diversity concentrations in Arizona. Arizona BBA surveys also discovered this unique area was found to have the lowest elevation breeding populations of many avian species in Arizona, these include: Spotted Owl, Northern Pygmy-Owl, Whip-poor-will, Acorn Woodpecker, Arizona Woodpecker, Elegant Trogon, Sulphur-Bellied Flycatcher, Rose-throated Becard, Eastern Bluebird, Painted Redstart, Hepatic Tanager, and Black-Headed Grosbeak. During ABBA surveys in 1993 and 1994, 3-4 pairs of Rose-throated Becards were found nesting in Sycamore Canyon. This is one of the highest concentrations ever found for this species in Arizona and in the United States. Through the years, this rugged canyon has attracted many resident and visiting birders in hopes of viewing the rare Mexican species that have occasionally been reported. These include such birds as the Black-capped

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Retrieved Text: James Billstine, SOU graduate student and Spotted Owl Survey volunteer. Learn about the spotted owl and other birds that share the habitat.
Meet at the PCT / Pilot Rock parking lot. Moderate hike.
With an introduction on bird calls.

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Retrieved Text: Mature, old-growth forests in the Pacific Northwest provide critical habitat for threatened and endangered species, including the northern spotted owl and marbled murrelet. Dominated by large Douglas-firs and western hemlocks, these established forests range in age from 200 to 1,000 years old. Yet wildfire activity is increasing across western North America, heightening concerns about severe fires that have the potential to kill the upper canopy layer of forests. Known as “stand-replacing fires”, these extreme events have important implications for forest ecosystems, initiating forest regrowth and altering habitat for wildlife.
Identifying locations that are protected from stand-replacing fire is an urgent management priority, particularly given projections of more extreme fires as climate conditions change. These “fire refugia” – places that remain unburned or experience minimal tree mortality compared to the surrounding landscape – can be key to biodiversity conservation and adaptation. Despite concerns about increasing fire severity, mapping of fire refugia and stand-replacing fire has not been completed for old-growth forests in the Pacific Northwest, hindering conservation planning for threatened and endangered species.
To address this need, researchers will map the probability of fire refugia and stand-replacing fire, based on topographic conditions, fire weather, fuel loads, and climate. They will then use this information to assess the likely future occurrence of old-growth, fire-resistant forests and young, post-fire forests in the Pacific Northwest under increasingly extreme fire weather. These maps will provide estimates of where old-growth forests are likely to persist, and where they are more susceptible to be lost to stand-replacing fires, supporting managers who are revising forest plans,

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Retrieved Text: With over 140 species of birds known to frequent Centennial Parklands, we are still delighted when a rare feathered visitor is spotted. This latest sighting has not only caught our attention, but that of the Australian birdwatching community.
Owls, while not unknown visitors to Centennial Park, are rarely sighted. However last week the rarest of them all – the Powerful Owl – was spotted by our friends and avid twitchers, Dan Hutton and his father Keith Hutton (Dan is better known as one of the brothers behind the magazine, The Beast).
Why is this an exciting sighting?
The sighting of a Powerful Owl is exciting for a number of reasons, most notably that it does not appear on Ern Hoskin’s bird list (which covered a 50 year period, up until 2009, and documents over 150 species that he spotted over that time). Ern’s list only contained one owl – the Southern Boobook Owl.
Sightings of the Powerful Owl, and the recently recorded Barn Owl, appear to be relatively new additions to the Parklands’ wildlife.
What is a Powerful Owl?
The Powerful Owl is the largest recorded owl in Australia and is one of the supreme nocturnal predators in the forests of south-eastern Australia. It is named so for its sheer size and very powerful heavy claws!
The largest species of the “hawk owl” group, the Powerful Owl measures in at 45–65 cm in length and spans 112–135 cm across the wings. Unlike most owl species, the male, weighs in at 1.15–1.7 kg and is slightly larger than the female, at 1.05–1.6 kg.
Why might

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Retrieved Text: Missing owl recaptured after fortnight Jump to media player A missing owl that escaped after her aviary door was left open has been recaptured.
Missing owl spotted on TV report Jump to media player The owl was caught on camera, but managed to evade its owner.
Escaped owl recaptured after two weeks away.
A missing owl that escaped after her aviary door was left open has been recaptured.
Dawn fled her home in Leiston along with her fellow Ural owl Misty two weeks ago.
Misty was caught after just a week, but it took a further week to captured his companion.

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Retrieved Text: Lowell Diller heading out to do some owl work in 2011.
Once again, our owl problem is in the news. National Geographic Daily News has a story today about the experiment to give northern spotted owls a chance at keeping a talon-hold on their habitat by killing barred owls.
"When I went out to do it the first time, I was shaking, I had to steady myself," he remembers. "I wasn't sure I could actually do it. It was so wrong to be shooting a beautiful raptor like this. It continues to be awkward to this day."
Zach St. George wrote about Diller's role in the barred-owl-removal experiment, part of a broader plan by the National Fish and Wildlife Service, for the North Coast Journal back in 2011. It, too, was called Shooting Owls.

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Retrieved Text: The spotted wood owl is an owl of the earless owl genus, Strix. It is an inhabitant of Singapore’s Jurong Bird Park.
Date Uploaded: Oct. 28, 2018, 10:02 p.m.

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Retrieved Text: Harbingers of Change: Owls of Mescalero For the Mescalero Apache, the owl is a messen-ger. Often misconstrued as a bad omen, the owls provide a warning that it’s time to pay attention, and that “when the world is changing, we need to listen.” For FFS Wild-life Biologist and Tribal Liaison Serra Hoagland, that warning is a timely one. She’s studying the Mexican Spotted Owl population on the Mescalero Apache reser-vation in New Mexico, a land steeped in cultural signifi-cance and whose tribal forest manage-ment team uses alternative methods to protect their forests from catastrophic wildfire - the biggest threat to the owl and to the environment in the Southwest from a changing cli-mate. Serra sees the owls as harbingers for these changes and an indicator species for forest health.
Serra’s work is highlighted in the new short film, “Messengers: Owls of Mescalero.” In it, filmmaker Janey Fugate explores the role Native American conser-vationists play in protecting wilderness, and how com-bining traditional ecological knowledge with Western science can address one of the most critical challenges facing the world of wildlife management.

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Retrieved Text: Port of Portland employees working out of our headquarters building have been treated to an up close and personal viewing of a barn owl over the last couple of days. The owl first appeared roosting on the window ledge on the south side of the building on Friday morning and has been spotted at a few different locations around the building since then. Take a look at a few of the great photos our staff were able to snap of our visitor.
According to The Raptor Institute, barn owls are one of the most widespread species of birds in the world. Birds can naturally be attracted to the open spaces at Portland International Airport, where our headquarters building is located, and we use a proactive Wildlife Management Program, to help prevent conflicts between birds and aircraft that utilize the facility.

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======= Instance Index 6246 =========
Input Text: Answer the following question given this paragraph: 

M = dRTP Exercise Radon (Rn) is a radioactive gas formed by the decay of naturally occurring uranium in rocks such as granite. It tends to collect in the basements of houses and poses a significant health risk if present in indoor air. Many states now require that houses be tested for radon before they are sold. Calculate the density of radon at 1.00 atm pressure and 20°C and compare it with the density of nitrogen gas, which constitutes 80% of the atmosphere, under the same conditions to see why radon is found in basements rather than in attics. Answer: radon, 9.23 g/L; N2, 1.17 g/L A common use of Equation 10.23 is to determine the molar mass of an unknown gas by measuring its density at a known temperature and pressure. This method is particularly useful in identifying a gas that has been produced in a reaction, and it is not difficult to carry out. A flask or glass bulb of known volume is carefully dried, evacuated, sealed, and weighed empty. It is then filled with a sample of a gas at a known temperature and pressure and reweighed. The difference in mass between the two readings is the mass of the gas. The volume of the flask is usually determined by weighing the flask when empty and when filled with a liquid of known density such as water. The use of density measurements to calculate molar masses is illustrated in Example 10.


Q: Radon (rn) is a radioactive gas formed by the decay of naturally occurring uranium in rocks such as granite. it tends to collect in the basements of houses and poses a significant health risk if present in indoor air. many states now require that houses be tested for radon before they are what?

 Choices:

- built

- seen

- modified

- built

A:

Target Text: sold

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Retrieved Text: Radon ( /?re?d?n/ ray-don) is a chemical element with symbol Rn and atomic number 86. It is a radioactive, colorless, odorless, tasteless noble gas, occurring naturally as the decay product of uranium. It is one of the densest substances that remains a gas under normal conditions and is considered to be a health hazard due to its radioactivity. Its most stable isotope, 222Rn, has a half-life of 3.8 days. Due to its intense radioactivity, it has been less well-studied by chemists, but a few compounds are known.
Radon is formed as part of the normal radioactive decay chain of uranium. Uranium has been around since the earth was formed and its most common isotope has a very long half-life (4.5 billion years). Uranium, radium, and thus radon, will continue to occur for millions of years at about the same concentrations as they do now.
Radon is responsible for the majority of the public exposure to ionizing radiation. It is often the single largest contributor to an individual’s background radiation dose, and is the most variable from location to location. Radon gas from natural sources can accumulate in buildings, especially in confined areas such as attics, and basements. It can also be found in some spring waters and hot springs.
Epidemiological studies shows a clear link between breathing high concentrations of radon and incidence of lung cancer. Thus, radon is considered a significant contaminant that affects indoor air quality worldwide. According to the United States Environmental Protection Agency, radon is the second most frequent cause of lung cancer, after cigarette

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Retrieved Text: Were you looking for information about Radon? Rayden is a common misspelling of radon.
Radon is an invisible, odorless, and naturally occurring radioactive gas that is formed from the decay of uranium in rocks and soil. People breathe it in every day in low levels (as the gas is present in nearly all air), but long-term exposure to high levels of radon can lead to lung cancer. The levels of this gas can be higher in homes that are well insulated, tightly sealed, and/or built on uranium-rich soil. Numerous tests are available to check for elevated radon levels in a home.

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Retrieved Text: Does radioactive dating with isotopes of uranium and thorium provide an estimate of the beginning middle or end of the periods of earth's formation?
Split and merge into it. This method estimates the age of the oldest unmelted surface rocks on earth. Since the surface of earth probably melted many times as the planed formed, the earth shoul dbe older than these rocks.
Does radioactive dating with isotopes of uranium and thorium provide an estimate of the beginning middle or end of the period of Earth's formation Explain your answer? Method of dating very old rocks by means of the amount of common lead they contain. Common lead is any lead from a rock or mineral that contains a large amount of lead and a s … mall amount of the radioactive precursors of lead i.
By this method, the age of the Earth has been estimated to be c. This figure is in good agreement with the age of meteorites and the age of the Moon as determined independently.
Radiometric dating is used to date rocks like at the grand canyon to approximately see how old the earth is. Radiometric dating is the principal source of information about the absolute age of rocks and other geological features, including the age of the Earth itself, and can be used to date a wide range of natural and man-made materials.
What is the radioactive gas produced from uranium and thorium? Radon gas is the radioactive gas produced from uranium and thorium. It forms from the radioactive decay of small amounts of uranium

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Retrieved Text: Radium is an element that is naturally occurring and can be found in many rock formations including granite. Many concrete buildings, particularly in and around the Charlotte Metro area have been constructed using concrete aggregate containing naturally occurring uranium and radium. In its refined state radium was used to make watch dials and aircraft instruments that glowed in the dark. It was also used in the fabric of gas lantern mantels to increase illumination.
Radon is a colorless, odorless, tasteless, naturally occurring radioactive gas that is formed by the natural decay of uranium. As radon gas decays, it produces solid decay products: polonium lead and bismuth that are often referred to as “radon progeny.” Unlike radon, these charged decay products can remain in the lungs and continue to cause risk of lung cancer for several years.
How does radon affect me?
Radon is the second leading cause of lung cancer in the United States and there is no level of radon that is considered to be safe. The Federal EPA, however, recommends that action be taken if indoor levels exceed 4.0 pCi/l (pico curies per liter). At a 4.0 pCi/l exposure rate there is a potential for 7 out of every 1000 people to contract lung cancer.
Radium in the concrete is a serious problem because as radium breaks down it produces radioactive radon gas which becomes air born as it is emitted from the concrete. To achieve energy efficiency goals, town homes and apartments, which are almost totally surrounded by concrete, have relatively low air exchange rates. This can

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Retrieved Text: The Radon Program is no longer maintained by DSHS. It is now managed by Texas Tech University.
The phone number for the program is: (806) 834-6202.
Is Radon a Problem in Texas?
Where Do I Get a Radon Test Kit?
Granite, as with other kinds of rocks and soils, contains some naturally occurring radioactive elements commonly referred to as Naturally Occurring Radioactive Material (NORM). NORM is made up of elements such as thorium, uranium, and potassium, which contribute to what scientists call "background" radiation. Background radiation is a combination of terrestrial and cosmic radiation that individuals are continuously exposed to as part of living on planet earth. In Texas, on average, we receive about 300 millirem each year from these sources. A person would receive approximately 20 millirem from a routine chest x-ray.
The amount of radioactivity in most granite is quite small. While it is possible to get a measurable level of direct radiation from some granite, in general it emits less radiation than we are regularly exposed to from background radiation. These levels are so low that they are not harmful to human health.
Radon is a naturally occurring radioactive gas that can be released during the decay of radioactive elements in granite countertops or can seep into homes from underground uranium deposits, and build up to higher than normal levels.(See: What is Radon?) Most areas of Texas are considered to be at a low risk level for high radon levels (See: The Texas Indoor Radon Survey), but it is still a good idea to test, and know for sure.
The

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Retrieved Text: Recall why radon is dangerous to humans.
Recall how to prevent radon poisoning.
Recall the process by which radon is produced.
Radon is a colorless, odorless gas, the primary source of indoor air pollution. It sinks in air because it has a high density as is therefore often found in the basements of homes, particularly in areas where with a lot of shale and boulders in the soil. Radon results from the radioactive decay of radium in the soil, and it further decays to produce radioactive daughters including polonium and lead. Radon gas, along with decay products that can attach to dust and airborne particles, enters the lungs and decays, producing alpha and beta radiation that damages DNA and causes lung cancer.
Discovered in 1900 by Friedrich Dorn, radon is a radioactive noble gas now regarded as a potential health hazard in some homes. It also has medical applications for cancer treatment. Its original name was to be niton for "shining" but it was eventually named as a derivative of radium. Radon is found in underground deposits where is it produced by uranium and radium decay.
Radon has a variety of sources, including uranium, and contains rocks like granite, shale, phosphate rock, and pitchblende. Radon can escape from these sources and migrate into the surrounding air and water supplies. It can be found in well water, natural gas sources, and building materials. Radon sources are found throughout the United States, in houses, schools, and businesses that have been constructed on top of radon-rich soil. Due to its heavy density, radon typically

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Retrieved Text: Summary: Thorium is a naturally occurring, radioactive substance. In the environment, thorium exists in combination with other minerals, such as silica. Small amounts of thorium are present in all rocks, soil, water, plants, and animals. Soil contains an average of about 6 parts of thorium per million parts of soil (6 ppm). More than 99% of natural thorium exists in the form of thorium-232. It breaks down into two parts-a small part called "alpha" radiation and a large part called the decay product. The decay product is also not stable and continues to break down through a series of decay products until a stable product is formed. During these decay processes, radioactive substances are produced. These include radium and radon. These substances give off radiation, including alpha and beta particles, and gamma radiation. Some rocks in underground mines contain thorium in a more concentrated form. After these rocks are mined, thorium is usually concentrated and changed into thorium dioxide or other chemical forms. After most of the thorium is removed, the rocks are called "depleted" ore or tailings. Thorium is used to make ceramics, gas lantern mantles, and metals used in the aerospace industry and in nuclear reactions. Thorium can also be used as a fuel for generating nuclear energy.

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Retrieved Text: Radon is a naturally occurring radioactive gas generated by the decay of uranium bearing minerals in rocks and soils. Exposure to indoor radon has been identified as the second leading cause of lung cancer after tobacco smoking. In an indoor environment, there are many factors affecting indoor radon concentrations. Those factors could be different in the Arctic regions than the rest of Canada. Based on the results from recently completed Canadian residential radon survey, this technical note assessed indoor radon characteristics and associated radiation doses in Canadian Arctic regions and compared them to the average radon characteristics in Canada. In Arctic health regions the percentage of homes above 200 Bq/m3 varied from 0% in Nunavut to 19.6% in Yukon Territory. On average, indoor radon characteristics in the Canadian Arctic regions are similar to the overall indoor radon characteristics in Canada. Although there are no significant differences in indoor radon exposure between the Canadian Arctic and rest of Canada, the average lung cancer incidence rate in the Arctic health regions is a factor of 1.6 higher than the national average lung cancer rate. The higher lung cancer rate in Canadian Arctic is likely due to the higher smoking rate in the northern communities.

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Retrieved Text: Radon is a naturally-occurring radioactive gas that results from the normal decay of uranium in rocks and soil. Like many gases, it is invisible; it is also odorless and tasteless. Radon seeps through the ground and into the air and, in some areas, it dissolves in the groundwater.
Radon gas formed in the ground can be very concentrated. Once it gets into the earth’s atmosphere, it dilutes and exists at very low levels. However, the concentrated gas can enter homes through cracks in the foundation, gaps in walls or insulation, and through the water supply. It can also be released from building materials. Indoors, particularly in well-insulated homes, the radon gas can become trapped and build to high levels.
As radon decays, it gives off minute radioactive particles. It is these particles that have been shown to damage the lungs and lead to lung cancer. According to the National Cancer Institute, radon is the second most common cause of lung cancer, though it represents a far smaller risk than cigarette smoking—the leading cause of lung cancer.
The Environmental Protection Agency (EPA) recommends taking action if the indoor radon level reaches 4 picocuries per liter (pCi/L) of air or more. The average indoor radon level is approximately 1.3 picocuries per liter (pCi/L); about 0.4 pCi/L of radon is normally found in the outside air.
Home radon test kits are widely available online and in home improvement stores. Short term detectors measure radon levels over the course of two to 90 days; long term detectors measure levels for as much as a

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Score: 69.538666
Retrieved Text: Arsenic is a naturally occurring element that is widely distributed in the Earth’s crust. Some areas of the United States contain unusually high natural levels of arsenic in rock, and this can lead to unusually high levels of arsenic in soil or water. We see higher-than-normal concentrations of Arsenic in the groundwater in many areas in the Lake Helena Watershed.
See the Arsenic map provided by the Water Quality Protection District on our Maps Page.
The drinking water standard is 10 ppb. We see concentrations much higher than this drinking water standard in the Helena Area.
View this website to get more details about arsenic.
Uranium is a naturally occurring element that has been in rocks since the earth was formed. Not all rocks contain uranium, but there are some places in Montana where uranium is in the bedrock and in valley fill sediments that have eroded from the bedrock of the adjacent upland or mountainous areas. Uranium breaks down (decays) very slowly into other elements including radium and radon gas. These other elements are part of a sequence formed through a transformation (decay) process that begins with the most prevalent form of “natural” (unprocessed) uranium (U-238).
not readily absorbed through the skin.
How do I know if there is arsenic or uranium in my groundwater?
What do I do if I find arsenic or uranium at high concentrations in my water?

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Score: 69.12921
Retrieved Text: This definition begs the questions: What are ionizing radiation or particles? Alternative Titles: radioactive nuclide, radioisotope, radionuclide Radioactive isotope, also called radioisotope, radionuclide, or radioactive nuclide, any of several species of the same with different masses whose nuclei are unstable and dissipate excess energy by spontaneously emitting in the form of , , and. In , for example, -60 is extensively employed as a radiation source to arrest the development of. The radioactive elements listed below shows all the decay modes of Uranium. However, it has limitations of range. The alpha rays are absorbed in the detector, while the non-harmful gamma rays are able to escape.
The circle of darker metal in the center is americium-241; the surrounding casing is aluminium. Beams of subatomic particles, such as protons, neutrons, or alpha or beta particles, directed toward diseased tissues can disrupt the atomic or molecular structure of abnormal cells, causing them to die. Provided there are not too many protons in the nucleus, other forces can hold the protons together. Retest again in five years. Just 25 parts per million 0. Unlike other naturally occurring radionuclides Pu gives off alpha, beta and gamma radiation. This will result in nuclear transformation.
Components of the radiation environment thatimpact the U. Because gross alpha radiation loses energy rapidly and within a short distance, it does not pass through skin. During those processes, the radionuclide is said to undergo. Most of those are only produced artificially, and have very short half-lives. If your natural reaction would be to throw water on this, that

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Score: 68.707344
Retrieved Text: Myth or Fact: Are your granite counters radioactive?
Any type of natural stone may contain trace amounts of naturally occurring radioactive minerals (NORMS). Some pieces of stone may contain more of these NORMS than others depending on the composition of the molten rock from which the stone was formed. Since granite is a natural stone that is mined from the earth, it may naturally contain radioactive elements, like radium. Radium is an earth metal that can decay and emit radon, an odorless, colorless, and tasteless radioactive gas that is the leading cause of lung cancer among nonsmokers. Ultimately, we know that your granite countertops may contain trace amounts of radium, but is it a myth or fact: are your granite counters radioactive?
The possibility of granite countertops being radioactive has been highly magnified by the media over the past decade. We’ve filtered through all the hype and headed straight to a reliable source who has recently commissioned two new studies on the relationship between granite and radiation. The Marble Institute of America is the leading source for information on the suitable applications of natural stone and the standards of workmanship and practice in the natural stone industry. Their recent studies measured both the radiation exposure of workers during granite fabrication and the radon exposure in granite quarries. The results from the studies confirm the truth about the radioactivity and safety of granite countertops.
So, are your granite countertops radioactive? This is a myth. Granite countertops do not emit a significant amount of radiation, and they are not considered dangerous.

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Score: 68.28583
Retrieved Text: During the course of a day, nearly everyone is exposed to low levels of radiation from both man-made and natural sources. Whether from x-rays, microwaves, or the sun, encountering radiation is unavoidable. Naturally occurring radioactive material, commonly known as NORM, includes all radioactive elements found organically in the environment.
While health risks from exposure to low levels of NORM are minimal, the extraction and production of oil, natural gas, or minerals can cause NORM to accumulate in hazardous concentrations.
NORM is produced during the natural decay process of uranium and thorium in the earth's crust. These elements and their decay chain products, known as daughter products, are unstable elements that emit radiation as they decay. Of the many radioactive isotopes produced during this process, the oil and gas industry generally measures only three: Radium 226, Radium 228, and Radon 222. These are the longest-lived elements in decay chains and can produce up to twenty radioactive daughters.
Radioactive isotopes will continue to decay until they become a stable isotope. In the case of radium, a non-radioactive form of lead is the final stable isotope.

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Score: 67.72601
Retrieved Text: Radon is a colorless, odorless gas that forms naturally when radioactive elements, such as uranium, decay.
These radioactive elements can be found in different amounts in soil and rock throughout the world. Though radon is present outdoors and indoors, it is often present in such small amounts that it does not pose a threat to human health.
However, the American Cancer Society notes that prolonged exposure to high levels of radon can lead to lung cancer.
People who work underground, such as miners, are most likely to be exposed to high levels of radon. People who work in factories where uranium is processed or those who come in contact with phosphate fertilizers are more likely to be exposed to high, and potentially dangerous, levels of radon.
Building materials made from substances that contain radon also can lead to unhealthy levels of radon exposure. However, such substances, which the ACS notes include concrete and wallboard, often give off very low levels of radon.

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Score: 67.68842
Retrieved Text: A radioactive noble gas which forms as a transient decay product in Th and U ores, from which it escapes to present a danger in mines and cellars.
The white powder in the flask is the ash produced by burning one of the gas mantles displayed in the thorium cube. It is composed of almost pure thorium oxide. As the thorium slowly decays (it has a long half life of 13 billion years) its atoms undergo a complex series of transmutations, eventually ending up as stable Pb-208 which is the commonest isotope in natural lead. Along the way, the decayed thorium atoms briefly exist as Rn-220 which has a half life of just under one minute. At any given time, there will be very approximately 100,000 atoms of radon gas inside the vessel.
Strictly speaking this yellow object does not contain any radon. Instead it is designed to detect the radioactive gas by absorbing it on activated charcoal. This is a monitoring device issued by the National Radiological Protection Board in the UK to people who live in houses built in parts of the country where the ground contains high levels of thorium and uranium ores. If cellars are not properly ventilated, potentially hazardous concentrations of radon gas can build up. Because radon is an unreactive noble gas, it is hard to filter. A single atom typically has a half-life of a few minutes or days and can easily be breathed in only to decay in the lungs to another radioactive element such as polonium. This element is

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Rank: 15
Score: 67.56006
Retrieved Text: The bright orange Fiesta dishware that many Americans use and collect could be giving off enough radon gas to pose a significant health risk, a geologist says.
"When we test homes and look for radon, we always suppose it comes from the ground," said Rudolph Hon of Boston College. "Maybe we need to make the public aware that some of it can be coming from the cabinet."
Fiesta ceramics made before 1972 "should be always considered as suspect" in homes where radon levels are high, concluded Hon and a graduate student, Christopher Zeman, in a paper presented recently in Binghamton, N.Y., to a meeting of the Geological Society of America.
The dishes' radioactive properties--gamma ray emissions from uranium-based paint in the bright orange variety--have been known for decades. The finding that the paint is also producing significant amounts of radon gas is new, Hon said.
Fiesta dishware sold by the millions in the 1930s and 1940s, and became one of the largest-selling lines in the country. It has recently become popular again among collectors, and is widely available in antique shops and flea markets.
Zeman, 22, said the study found that a single Fiesta plate in an unventilated, 15-by-15-foot room would produce radioactive radon gas at 28 picocuries per liter--a concentration seven times the level considered safe by the federal government.
The gas, radon-222, is produced by the gradual decay of uranium-238.
The radon is believed to escape from the plates through microscopic cracks in the glaze. Fiesta ware in other colors is not radioactive, Hon said.
More than half the radiation to which

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Rank: 16
Score: 67.34608
Retrieved Text: Uranium is a common naturally occurring and radioactive substance. It is a normal part of rocks, soil, air and water. Uranium occurs in nature in the form of minerals, but never as a metal. Uranium enters water by leaching from soil and rocks, or in releases from processing plants. Uranium has demonstrated toxic effects on human kidneys leading to their inflammation and changes in urine composition. Uranium can decay into other radioactive substances, such as radium, which can cause cancer with extensive exposure over a long period of time (U.S. EPA, 2013).
Click here to open WQA's Technical Fact Sheet on Uranium.

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Rank: 17
Score: 66.99294
Retrieved Text: Watch this WHSV news segment.
Radon is something you can’t see or smell but, you need to know about to keep your family safe.
It’s a naturally occurring radioactive gas that is likely in your home and specialists say one in three homes in the Valley have unsafe levels.
The rocky soil in the area makes homes, businesses and apartment buildings more susceptible.
The radon comes from decaying uranium and thorium, which exist naturally in the soil and rocks.
Continuously breathing in unsafe levels of radon is the equivalent of smoking numerous cigarettes per day.
Keith Micallef, the owner of Accurate Home Inspections and a Certified Radon Specialist, says he has seen more people testing.

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Rank: 18
Score: 66.710526
Retrieved Text: Mining and minerals - ANSTOIn milling and flotation operations, instruments using radioactive sources are widespread. These devices have the advantage of providing reliable non-contact measurement. Examples include the measurement of density and moisture in ore or slurries (important for process control and achieving final concentrate target.equipment that measuring radiation in mining,Radiation protection guidelines on mining in South Australia .Jan 18, 2010 . The use of appropriate personal protective equipment (PPE) and hygiene procedures are an important part of radiation . Before leaving the site, background gamma dose rates must be similar to initial background levels. The measurement method should be defined in the RMP and records kept of the.
An investigation into radiation exposures in underground non .
Radon progeny concentration by both grab sampling and automatic devices were undertaken at selected mines. . Kompa R, Pensko J and Schmier H 1985 Measurements of radon and decay products in non-uranium mines of the Federal Republic of Germany using active and passive methods Occupational Radiation.
also arise from equipment containing human-made radioactive sources, such as thickness and density gauges, and from radiation generators, such as X-radiography equipment [1, 2]. Nuclear gauges. Nuclear measurement gauges for industrial process measurements have been around for many years. They have.
Sources of Radon and its Measurement Techniques in Underground .
This study aims to identify the potential sources of radon exhalation and its measurement in underground uranium mines to control the radiation levels within safe limits and protect miners from ... Disturbances caused by the movement of mine workers and mining equipment may also enhance the

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Rank: 19
Score: 66.234055
Retrieved Text: Radon is an odorless, colorless, tasteless, radioactive gas. Radon comes from the decay of radioactive uranium that can be found in small amounts in rocks and soil throughout nature. In areas with disturbed earth, and loose fill, like when a home is built, radon escapes from the soil.
Generally, the air inside a home is lower pressure than the air outside, and combined with the warmer air rising inside, up to 20 percent of the air inside a house can come from the basement. When soil gas and air from fill enter the basement, it may include radon, which is then trapped inside house.
Radon gas continues to radioactively decay once inside the house, producing polonium, bismuth, and lead, which are also radioactive. As these radioactive elements transform, radioactive alpha and beta particles are released, and when inhaled and in contact with living lung tissue, can lead to cancer.
Radon gas exposure is the number one cause of cancer for non-smokers, even greater than second-hand smoke. Most people are exposed to radon gas inside their own homes, and this is their greatest exposure to natural ionizing radiation.
Any home can have a radon problem, the only way to know is to test. Some new homes are built with radon resistant construction techniques, it is still a good idea to plan a radon test to ensure the radon concentration is below the EPA action level. It is easy to add a professional radon test to your home inspections when buying a house.

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Rank: 20
Score: 66.03719
Retrieved Text: An office in Co Cork has been identified as having the second highest radon reading ever detected in Ireland.
The Radiological Protection Institute said the level of the radioactive gas present at The Corkman newspaper in Mallow was 60 times higher than the acceptable limit.
Radon is the second biggest cause of lung cancer in Ireland, causing up to 200 deaths per year.
It is a colourless, odourless, tasteless gas which occurs naturally from the decay of radioactive uranium in rocks and soils. It only becomes a problem when it builds up in basements of houses and offices.
The institute said levels at one office of The Corkman newspaper in Mallow would be equivalent to receiving 39 chest X-rays per day, or nearly 10,000 in a working year.
However, the RPII said the office in question was largely unoccupied, and so the risk to employees was significantly reduced.
The RPII's Chief Executive, Dr Ann McGarry, said over 100,000 homes and offices are estimated to be at risk and while the Corkman took the appropriate action, many others were being irresponsible for not testing for radon.

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Rank: 21
Score: 65.95956
Retrieved Text: “What’s radon?” That question came up in a conversation recently. I suspect that the majority of North Dakotans have heard something about radon in our soils and that it is associated with lung cancer. It is definitely here, but I rarely hear mention of radon in conversations.
Radon is an element. It is a colorless, odorless, and tasteless radioactive gas. It is on the periodic table of elements over on the far-right column. Its symbol is Rn, and it has an atomic number of 86. But it is the radioactive aspect of radon that is of concern.
Radioactive substances are unstable, and as a result give off radiation. Radon is one of several breakdown products in the decay of Uranium. Uranium may be found in bedrock, water, or soil, but remember that radon is a gas, so may also be found in the air. It might surprise you, but exposure to radon ranks second only to smoking as a cause of lung cancer.
Radon is not much of a risk in the outdoors because it is so diluted in the atmosphere. But in buildings close to the ground such as basements, first floors, and crawlspaces, particularly with poor ventilation, radon may move up from the ground and through porous material, cracks in the foundation, sump holes, and the like to become concentrated in the space above.
Here in the United States, it has been estimated that 1 in 15 homes have elevated levels of radon. A quick look at the Environmental Protection Agency’s map of radon risk levels shows that

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Rank: 22
Score: 64.84964
Retrieved Text: Were you looking for information about Radon? Redon is a common misspelling of radon.
Radon is a radioactive gas that is present in nearly all air. The gas, which is odorless, invisible, and tasteless, is released from the normal decay of uranium in rocks and soil. People who inhale high levels of radon are at an increased risk for developing lung cancer. The gas can enter homes through cracks in floors, walls, or foundations, and collect indoors. Tests are available to determine if a home has elevated radon levels.

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Rank: 23
Score: 64.82419
Retrieved Text: The Standard Radiological test includes analysis for uranium, gross alpha & beta and radon. Uranium is a naturally occurring element that is considered mildly radioactive. Uranium is present in most soils at a couple of parts per million, but can be much higher in certain rock formations. Uranium is known to cause problems with kidney toxicity and potentially some forms of cancer. Gross alpha particles emit radiation due to unstable atoms and include isotopes such as uranium 238, radium 226, radon 222 and thorium 232. Gross beta particles are subatomic particles emitted from radioactive atoms. Some beta emitters include tritium, cobalt-60, strontium-90 and radium 228. Running a gross alpha and beta test will give you a general idea of the level of radioactivity and can be less expensive than running tests for the individual isotopes which contribute to radiation. Radon is a gas that can accumulate in groundwater. It is a health concern because it can be released into the air and when inhaled is known to cause lung cancer.

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Rank: 24
Score: 64.79463
Retrieved Text: While some have dubbed Anchor Home Inspection The Best Home Inspection Company CT, did you know we also provide Radon Testing? In case you didn’t know you know…. We do!
Radon is a colorless, odorless, radioactive gas given off from uranium, a naturally occurring mineral in our earth’s rocks and soil. In normal circumstances, radon rises up through the soil and dissipates in the air outside. However, radon becomes concerning when it seeps through cracks, loose fitting pipes, sump pits, dirt floors, slab joints or block walls and starts to accumulate in your home or building.
Radon is the number killer for lung cancer among non smokers. Testing for radon is the only way to know if you or your loved ones are being exposed to it. We use electronic, calibrated radon monitors that test the radon levels.
For more information on Radon Testing visit our Radon page by clicking here.
Anchor Home Inspections provides quality Radon Testing to Rhode Island and Connecticut. Contact us to schedule a home inspection or any of our other home inspection services.

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Rank: 25
Score: 63.840015
Retrieved Text: The new year is a good time to test for radon, as January is National Radon Action month.
“The biggest danger of radon is lung cancer. It’s an odorless, colorless and tasteless gas that is in elevated levels in one in fifteen homes in the U.S.,” said Derek Cooper, the University of Georgia Cooperative Extension’s radon educator.
“We emphasize those characteristics because the only way to detect radon is to test for it,” he said.
According to Cooper, 800 people die every year from the effects of radon.
According to Cooper, alpha particles are a type of radiation that are released when radon breaks down. They are large physical particles that cannot break through skin and can cause damage when breathed.
The health effects from high exposure to radon can resemble those from smoking and smokers face a greater risk of lung cancer if they are exposed to radon, said Cooper.
“It is particularly important for anyone who smokes or has smoked to test for radon,” he said.
Radon results from the breakdown of uranium, which naturally occurs in granite and rocky soils.
According to Cooper, Georgia has granite underneath its soil mostly in the northern half of the state above the Fall Line, an area that divides the Piedmont and Coastal Plains regions. This area includes Coweta County.
Between March 2003 and July 2017, Coweta County had 866 self-reported radon tests, with 182 tests having elevated levels.
According to radon-faq.com, a pCi is a measure of the rate of radioactive decay of radon.
One pCi is one trillionth of a Curie, 0.037 disintegrations per second, or

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Rank: 26
Score: 63.7781
Retrieved Text: Radon is a radioactive gas formed by the natural decay of uranium in soil and rocks. As a naturally occurring substance, it can be found in any type of building, seeping from the ground through cracks and openings in the floors and walls. Without proper ventilation, a home or building can have increased concentrations of radon in indoor air, which could pose significant health risks to occupants. As a harmful substance, it should be detected early on to prevent its deadly effects. Home radon testing in Champaign IL must be performed to detect levels of radon and to apply mitigating procedures if necessary.
Home radon testing in Champaign IL is needed because we can't see, smell, or taste radon. These characteristics make it easy for the harmful substance to go undetected. Radon is a major cause of lung cancer, so testing homes for this dangerous gas is very important. At Callaway and Associates, we have over 20 years of experience in testing homes for harmful levels of radon. With our help, homeowners - buyers and sellers alike - have peace of mind knowing that our radon testing techniques yield accurate results that in turn allows for proper remediation or mitigation plans if necessary.
Callaway and Associates is a locally owned and operated inspection and testing company. We are licensed by the State of Illinois Department of Financial & Professional Regulation, Division of Real Estate to perform home inspection in Champaign IL and by the Illinois Emergency Management Agency (IEMA) Division of Nuclear Safety, State of Illinois Radon Program

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Rank: 27
Score: 63.705456
Retrieved Text: Radon is a natural occurring chemically inert gas. It comes for the radioactive decay of common uranium in soil that enters building directly beneath and a few meters around the foundation. Radon can enter all types of buildings and the main concern is when radon has the chance to accumulate. Tight homes do not cause radon; they increase the likelihood of radon lingering instead of escaping through ventilation.
Radon is an unstable atom and will break down into a family of elements called radon decay products. These decay products attach to the surface of dusts and become logged in the lungs. When exhaled, the radon leaves but the decay products remain in the lungs which have been proven to cause lung cancer. The chance of lung cancer increases greatly for smokers as they already have damaged, weaker lungs. For a non smoker, if exposed to the minimum suggested EPA actionable level of 4 pCi/L, there would be the equivalent risk ratio of dying in a car crash.
There are many ways radon can enter a building. The main reason is that buildings naturally create vacuum effects. Vacuums are caused by either temperature induced stack effects or mechanical exhaust systems. Their are typically four ways radon enters a structure: Vacuum effects, water, diffusion, and emanation.
A good way to visualize is to imagine a bathroom fan or over-the-stove fan turned on and creating a negative pressure in the home. If it is winter, the windows and doors in the home closed tight so a lot of air is being drawn

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Rank: 28
Score: 63.68009
Retrieved Text: Luz Huntington-Moskos, PhD, RN, CPN, UofL School of Nursing assistant professor, recently published the findings in the journal Public Health Nursing. The two-year study was funded by a $210,000 supplemental grant from the National Institute of Environmental Health Sciences as part of a broader study led by University of Kentucky College of Nursing Professor Ellen Hahn, PhD, RN, FAAN.
Hahn’s study Freedom from Radon Exposure and Smoking in the Home (FRESH) Dual Home Screening for Lung Cancer Prevention gave about 550 participants test kits to measure radon and secondhand smoke levels in their homes. Based on the test results, participants received tailored interventions designed to reduce environmental risks for lung cancer.
Huntington-Moskos analyzed data collected from Hahn’s study, focusing on whether parents with children 18 and younger living in the home were concerned about lung cancer risk and the dangerous combination of radon and secondhand smoke.
Radon, a naturally occurring radioactive gas resulting from the breakdown of uranium in the soil, enters homes and other buildings through small cracks and holes in the foundation and can become trapped indoors. Radon and tobacco smoke have synergistic effects that greatly increase the likelihood of lung cancer.
Increasing awareness on preventing exposure to radon and tobacco smoke is especially critical in Kentucky, which has the highest incidence of lung cancer in the country, according to the Centers for Disease Control and Prevention.
The state’s geology also allows for strong concentrations of radon to release from the ground.
Inexpensive radon test kits can be bought at home improvement stores. Installing a ventilation system, which can be

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Rank: 29
Score: 63.502434
Retrieved Text: A: Radon is a radioactive, colorless, odorless, and tasteless gas occurring naturally as a decay product of radium, and thus radon is not readily detectible or observable by the human senses. Radon is considered a health hazard due to its radioactivity, and studies have shown a link between high concentrations of radon and lung cancer. According to the U.S. Environmental Protection Agency (EPA), radon is the second highest cause of lung cancer after cigarette smoking, and radon causes an average of 21,000 lung cancer deaths per year in the United States.
Radon levels are measured by picocuries per liter (pCi/L). An average of about 1.0 to 2.0 pCi/L is typical for indoor radon exposure, and the EPA recommends immediate remedial action for anything above 4.0 pCi/L.
Radon is produced by the radioactive decay of radium-226, which is found in uranium ores, phosphate rock, which has been mined extensively in Polk County over the years, shales, igneous and metamorphic rocks such as granite, and to a lesser degree in common rocks such as limestone, which is found throughout all of Florida.
Radon typically enters a building directly from the soil through the lowest level of a building that is in contact with the ground. Entry points of radon into a building, particularly an older building, are cracks, gaps, and cavities in the building as well as the water supply.
Of great concern in Polk County is phosphate mining and the impact phosphate mining has had on the environment over the years. Phosphate is typically found buried beneath an approximate 10 to

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