Infobox Embryology Name Vitellinemembrane Latin membrana vitellina GraySubject 5 GrayPage 45 Image Caption Image2 Caption2 System CarnegieStage Days Precursor GivesRiseTo MeshName Vitellinemembrane MeshNumber A16.631.886 DorlandsPre m 08 DorlandsSuf 12523303 The vitellinemembrane is a structure directly adjacent to the outer surface of the plasma membrane of an ovum . It is composed mostly of protein fibers, with protein receptors needed for sperm binding which, in turn, are bound to sperm plasma membrane receptors. The species specificity between these receptors contributes to prevention of breeding between different species. It is called zona pellucida in mammal s. As soon as the spermatozoon fuses with the ovum , signal transduction occurs, resulting in an increase of cytoplasmic calcium ions. This itself triggers the cortical reaction , which results in depositing several substances onto the vitellinemembrane through exocytosis of the cortical granules, transforming it into a hard layer called the fertilization membrane , which serves as a barrier inaccessible to other spermatozoa. This phenomenon is the Egg activation Fast and slow block to polyspermy slow block to polyspermy . See also Zona pellucida Egg activation Cortical reaction Perivitelline space Gray s Embryology Category Embryology developmental biology stub es Membrana vitelina ... more details
Vitelline can refer to Vitelline duct Vitelline veins Vitellinemembrane disambig Long comment to prevent listing on Special Shortpages.......................................................................... more details
Infobox Embryology Name Vitelline arteries Latin GraySubject GrayPage Image Gray31.png Caption Model of human embryo 1.3 mm. long. Vitelline arteries not shown, but vitelline arteries labeled at center left. Image2 Caption2 System CarnegieStage 13 Days 28 Precursor GivesRiseTo MeshName MeshNumber DorlandsPre DorlandsSuf The vitelline arteries are the arterial counterpart to the vitelline veins . Like the veins, they play an important role in the vitelline circulation of blood to and from the yolk sac of a fetus. They are a branch of the dorsal aorta . They give rise to the celiac artery , superior mesenteric artery , and inferior mesenteric artery . ref GPnotebook 120913981 ref References references External links EmbryologyUNC cardev 009 http isc.temple.edu marino embryology Heart98 heart text.htm EmbryologyTemple Heart98 heart97a sld021 http www.ana.ed.ac.uk database humat notes extraemb yolksac vitart.htm http www.med.umich.edu lrc coursepages M1 embryology embryo 13cardiovascular system.htm http www.med.mun.ca anatomyts embryo emb6.htm Development of circulatory system Category Embryology of cardiovascular system circulatory stub ... more details
Image Gray22.png thumb Human embryo of 2.6 mm. Image Gray458.png thumb Diagram of the vascular channels in a human embryo of the second week. After Eternod. The red lines are the dorsal aort continued into the umbilical arteries . The red dotted lines are the ventral aort , and the blue dotted lines the vitelline veins . Vitelline circulation refers to the system of blood flowing from the embryo to the yolk sac and back again. The yolk sac is situated on the ventral aspect of the embryo it is lined by endoderm , outside of which is a layer of mesoderm . It is filled with fluid, the vitelline fluid , which possibly may be utilized for the nourishment of the embryo during the earlier stages of its existence. Blood is conveyed to the wall of the sac by the primitive aort , and after circulating through a wide meshed capillary plexus , is returned by the vitelline veins to the tubular heart of the embryo. This constitutes the vitelline circulation, and by means of it nutritive material is absorbed from the yolk sac and conveyed to the embryo. External links GrayPage 54 http www.med.umich.edu lrc coursepages M1 embryology embryo 13cardiovascular system.htm Overview of three circulation systems Gray s Category Embryology of cardiovascular system ... more details
Infobox Embryology Name Vitelline duct Latin ductus vitellinus GraySubject 10 GrayPage 54 Image Gray30.png Caption Fetus of about eight weeks, enclosed in the amnion . Vitelline duct labeled at lower right. Image2 Gray982.png Caption2 Sketches in profile of two stages in the development of the human digestive tube. Vitelline duct labeled on bottom image. System CarnegieStage Days 28 Precursor midgut , yolk sac GivesRiseTo MeshName Vitelline Duct MeshNumber A16.254.891 DorlandsPre DorlandsSuf In the human embryo , the vitelline duct , also known as the omphalomesenteric duct, is a long narrow tube that joins the yolk sac to the midgut lumen of the developing fetus. ref name usmle1 122 Cite book last1 Le first1 Tao first2 Vikas last2 Bhushan first3 Neil last3 Vasan title First Aid for the USMLE Step 1 2010 20th Anniversary Edition location USA publisher The McGraw Hill Companies, Inc. year 2010 pages 122 isbn 978 0 07 163340 6 ref It appears at the end of the fourth week, when the yolk sac presents the appearance of a small pear shaped vesicle the umbilical vesicle . Obliteration Generally, the duct fully obliterates narrows and disappears during the 5 6th week of fertilization age 9th week of gestational age , but a failure of the duct to close is termed a vitelline fistula. This results in discharge of meconium from the umbilicus. ref name usmle1 122 About two per cent of fetuses exhibit a type of vitelline fistula characterized by persistence of the proximal part of the vitelline duct as a diverticulum protruding from the small intestine , Meckel s diverticulum , which is situated about two feet above the ileocecal junction and may be attached by a fibrous cord to the abdominal wall at the Navel umbilicus . Afterbirth The vesicle can be seen in the afterbirth as a small, somewhat oval shaped body, the diameter of which varies from 1 mm to 5 mm. It is situated ... yolk stalk Extraembryonic and fetal membranes DEFAULTSORT Vitelline Duct Category Embryology ... more details
Taxobox image Vitelline Warbler.jpg status NT status system IUCN3.1 regnum Animalia phylum Chordata classis Aves ordo Passeriformes familia Parulidae genus Dendroica species D. vitellina binomial Dendroica vitellina binomial authority Charles B. Cory Cory , 1886 synonyms The Vitelline Warbler Dendroica vitellina is a songbird species in the New World warbler family biology family Parulidae . It is found in the Cayman Islands and on the Swan Islands, Honduras Swan Islands in Honduras . Its natural habitat s are subtropical or tropical dry forest s, subtropical or tropical dry shrubland , and urban area s. It is becoming rare due to habitat loss . References BulletinOfTheBritishOrnithologistsClub101 339. BirdLife International 2004. http www.iucnredlist.org search details.php 6423 all Dendroica vitellina . http www.iucnredlist.org 2006 IUCN Red List of Threatened Species. Downloaded on 25 July 2007. Raffaele, Herbert James Wiley, Orlando Garrido, Allan Keith & Janis Raffaele 2003 Birds of the West Indies , Christopher Helm, London. Parulidae stub DEFAULTSORT Warbler, Vitelline Category Birds of Honduras Category Birds of the Cayman Islands Category Dendroica Vitelline Warbler de Dotter Walds nger eo Vitelina parulio fr Paruline des Ca mans pt Dendroica vitellina ... more details
Infobox Embryology Name Vitelline veins Latin GraySubject 135 GrayPage 518 Image Gray475.png Caption The liver and the veins in connection with it, of a human embryo , twenty four or twenty five days old, as seen from the ventral surface. Vitelline veins visible at center bottom. ad System CarnegieStage 9 Days 28 Precursor GivesRiseTo MeshName MeshNumber DorlandsPre v 04 DorlandsSuf 12849063 The vitelline veins are veins which drain blood from the yolk sac . Path They run upward at first in front, and subsequently on either side of the intestinal canal . They unite on the ventral aspect of the canal, and beyond this are connected to one another by two anastomotic branches, one on the dorsal, and the other on the ventral aspect of the duodenal portion of the intestine , which is thus encircled by two venous rings into the middle or dorsal anastomosis the superior mesenteric vein opens. The portions of the veins above the upper ring become interrupted by the developing liver and broken up by it into a plexus of small capillary like vessels termed sinusoids . Derivatives The vitelline veins give rise to Hepatic veins Inferior portion of Inferior vena cava Portal vein Superior mesenteric vein ref name LHC cite web url http mc.lifehugger.com moc 1232 Vitelline veins Derivatives title Vitelline veins Derivatives publisher LifeHugger accessdate 2009 12 11 ref The branches conveying the blood to the plexus are named the venae advehentes , and become the branches of the portal vein . The vessels draining the plexus into the sinus venosus are termed the venae revehentes , and form the future hepatic veins . Ultimately the left vena revehens no longer communicates directly with the sinus venosus, but opens into the right vena revehens. The persistent part of the upper venous ring, above the opening of the superior mesenteric vein, forms the trunk of the portal vein . Additional images ... Development of circulatory system DEFAULTSORT Vitelline Veins Category Embryology of cardiovascular ... more details
or electrical gradients of the membrane process. Membranes can be generally classified into synthetic membrane s and biological membrane s. ref cite book author Mulder, Marcel title Basic principles of membrane technology publisher Kluwer Academic Springer location year 1996 edition 2 isbn 0 7923 4248 8 ref References reflist Category Membrane technology bg cs Membr na de Membran et Membraan es Membrana fr Membrane io Membrano id Membran it Membrana he lv Membr na pl Membrana ... more details
Taxobox name Vitelline Masked Weaver image Dotterweber Vitelline Masked Weaver Textor vitellinus cropped.jpg status LC status system IUCN3.1 regnum Animalia phylum Chordata classis Aves ordo Passeriformes familia Ploceidae genus Ploceus species P. vitellinus binomial Ploceus vitellinus binomial authority Martin Lichtenstein Lichtenstein , 1823 synonyms Image Vitelline Masked Weaver male RWD.jpg left thumb Serengeti National Park, Tanzania The Vitelline Masked Weaver Ploceus vitellinus is a species of bird in the Ploceidae family. It is found in Benin , Burkina Faso , Cameroon , Central African Republic , Chad , Democratic Republic of the Congo , Equatorial Guinea , Ethiopia , Gambia , Ghana , Kenya , Mali , Mauritania , Niger , Nigeria , S o Tom and Pr ncipe , Senegal , Somalia , Sudan , Tanzania , Togo , and Uganda . References BirdLife International 2004. http www.iucnredlist.org search details.php 53197 all Ploceus vitellinus . http www.iucnredlist.org 2006 IUCN Red List of Threatened Species. Downloaded on 26 July 2007. Ploceidae Category Ploceus Ploceidae stub de Dotterweber fr Tisserin vitellin hu Feketearc sz v mad r sv Plommongul v vare ... more details
Membrane most commonly means a thin, selective barrier, but it is sometimes used for films that function as separators, like biological membranes. Membrane may also refer to Acoustic membrane Amnion Basement membrane Biological membrane Cell membrane Chorioallantoic membrane Fetal membrane Inner membraneMembraneMembrane keyboard Membrane structure Membrane M Theory Mucous membrane Outer membrane disambiguation Serous membrane Synthetic membrane The Membranes , a punk band Tympanic membrane disambiguation ... more details
Unreferenced date December 2009 Membrane biology is the study of the Biology biological and Biochemistry physiochemical characteristics of Biological membrane membranes . DEFAULTSORT Membrane Biology Category Membrane biology Biology stub ... more details
Membrane glycoproteins are membrane protein s which play important roles in cell recognition. Examples include Fibronectin Laminin Osteonectin See also Glycocalyx External links MeshName Membrane glycoproteins membrane protein stub Glycoproteins Cell membranes Category Glycoproteins ... more details
Tectorial membrane can refer to Tectorial membrane cochlea Tectorial membrane axis disambig ca Membrana tect ria Long comment to avoid being listed on short pages ... more details
disorder s in humans. See also For eukaryotes Intermembrane space Chloroplast membrane For bacteria periplasmic space Bacterial outer membrane DEFAULTSORT Inner Membrane Category Membrane biology cs ... more details
Periodontal membrane may refer to The periodontal ligament PDL , largely referred to as the periodontal membrane outside of the United States An artificial periodontal membrane , used to block the spread of growing epithelium after periodontal surgery. disambig ... more details
Membrane biophysics is the study of biological membrane s using Physics physical , computation computational , Mathematics mathematical , and Biophysical techniques biophysical methods . See also Lipid polymorphism Lipid Amphiphile References references Category Biophysics cell biology stub Membrane Biophysics is the use of physical methods applied to cell membrane functions. ... more details
Image Semipermeable membrane.png thumb 250px Scheme of semipermeable membrane during hemodialysis , where red is blood, blue is the dialysing fluid, and yellow is the membrane. A semipermeable membrane , also termed a selectively permeable membrane , a partially permeable membrane or a differentially permeable membrane , is a membrane that will allow certain molecule s or ion s to pass through it by diffusion ... as the permeability of the membrane to each solute. Depending on the membrane and the solute, permeability may depend on solute size, solubility , properties, or chemistry. How the membrane is constructed ... and synthetic materials thicker than a membrane are also semipermeable. One example of this is the thin film on the inside of an Egg biology egg . An example of a semi permeable membrane is the lipid bilayer , on which is based the plasma membrane that surrounds all cell biology biological cell ... layer, the phospholipid bilayer is a semipermeable membrane that is very specific in its permeability ... outside and within the cell. The hydrophobic tails are the layer hidden in the inside of the membrane ... of reverse osmosis , thin film composite membrane s TFC or TFM are used. These are semipermeable ... small molecules that cannot be filtered. Another example of a semipermeable membrane is dialysis tubing . Other types are cation exchange membrane CEM , charge mosaic membrane CMM , bipolar membrane BPM , anion exchange membrane AEM ref http www.ncbi.nlm.nih.gov pubmed 18547927?dopt Abstract Effect of the type of ion exchange membrane on performance, ion transport, and pH in biocatalyzed electrolysis of wastewater ref alkali anion exchange membrane AAEM and proton exchange membrane PEM . The diffusion of water through a selectively permeable membrane is called osmosis . References reflist External links http www.euromemhouse.eu EuroMemHouse European Membrane House http www.iupac.org publications pac 1996 pdf 6807x1479.pdf Membrane terminology. International Union of Pure and Applied ... more details
Membrane fouling is a process where solute or particles deposit onto a Artificial membranemembrane surface or into membrane pores in a way that degrades the membrane s performance. It is a major obstacle to the widespread use of this Membrane technology technology . Membrane fouling can cause severe flux decline and affect the quality of the water produced. Severe fouling may require intense chemical cleaning or membrane replacement. This increases the operating costs of a Sewage treatment treatment ... Baker, R.W. 2004 . Membrane Technology and Applications, England John Wiley & Sons Ltd ref Fouling can ... to the membrane surface. Reversible fouling can be removed by a strong shear force of backwashing . Formation ... flow on membrane fouling for wastewater treatment. J. Separation and Purification Technology 45 68 78. ref Factors affecting membrane fouling Factors that affect membrane fouling Membrane properties such as pore size, hydrophobe hydrophobicity , pore size distribution and membrane material. Solution .... Operating conditions such as pH , temperature , flow rate and pressure. Measure of membrane fouling Flux and transmembrane pressure TMP are the best indicators of membrane fouling. Under constant ... operation, flux declines due to membrane fouling. Fouling control Even though membrane fouling is an inevitable phenomenon during Membrane technology membrane filtration , it can be minimised by strategies such as cleaning, appropriate membrane selection and choice of operating conditions. Membranes .... Another strategy to minimise membrane fouling is the use of the appropriate membrane for a specific operation. The nature of the feed water must first be known then a membrane that is less prone to fouling with that solution is chosen. For aqueous filtration , a hydrophile hydrophilic membrane is preferred. Operating conditions during membrane filtration are also vital, as they may affect ... technology Category Fouling Category Membrane technology de Fouling Membrantechnik ... more details
Unreferenced stub auto yes date December 2009 Expert subject Medicine date November 2008 The otolithic membrane is a gelatinous biological membrane membrane located in the vestibular apparatus of the inner ear , and plays an essential role in the brain s interpretation of equilibrium. Both the saccular macula and utricular macula are covered by an otolithic membrane, thus providing the common name of the otoliths to the Utricle ear utricle and saccule . The membrane is composed of crystalline particles of calcium carbonate called otolith otoliths . When the head is moved the otoliths shift, causing cilia in the nearby saccule and Utricle ear utricle to distort. This produces nerve signals which are sent to the brain, which then uses them to establish its sense of balance. The embedded crystals are very dense and make the density of the otolithic membrane higher than that of the endolymph surrounding it. When the head accelerates along a line or tilts to change its orientation to gravity, the otolithic membrane shifts relative to the bone supporting the maculae. This shift bends the hair cells whose processes are embedded in the otolithic membrane. Category Vestibular system DEFAULTSORT Otolithic Membrane Med stub ... more details
Unreferenced date December 2009 In biochemistry , the membrane topology of an transmembrane protein describes which portions of the amino acid amino acid sequence of the protein lie within the plane of the surrounding lipid bilayer and which portions protrude into the watery environment on either side. More succinctly, the membrane topology describes which regions of the polypeptide chain span the membrane. Description Because biochemists know the hydrophobicity of amino acids individually, the membrane topology of a protein and indeed whether or not it is an integral membrane protein in the first place often may be predicted accurately on the basis of a protein s sequence alone which of course in turn may be predicted solely from the DNA sequence nucleotide sequence of a gene . Such predictions are most reliably based on the assumption that the lipid bilayer spanning portions of a transmembrane protein will assume an transmembrane helix alpha helical secondary structure . Since membrane topology is frequently the first available structural information about a protein after sequencing, integral membrane proteins are often classified or grouped according to this feature. In classifying proteins in this way, biologists look at the number of times the peptide chain is predicted to cross the membrane and may in fact name a class on this basis e.g. G protein coupled receptor 7TM receptors . Membrane topology predictions also can be invaluable for developing antibodies, drugs or other reagents that will bind and or affect the function of the protein. DEFAULTSORT Membrane Topology Category Integral membrane proteins Category Membrane biology ... more details
The interfemoral membrane , or patagium uropatagium , is the membrane that stretches between the legs of bat s, used for flight, and in the case of microbat insect eating bats , for catching prey. External links http www.britannica.com eb article 51421 Encyclopaedia Britannica article on bats Category Bats animal anatomy stub fr Membrane interf morale ... more details
Atlantooccipital membrane can refer to Anterior atlanto ccipital membrane Posterior atlanto ccipital membrane disambig Short pages monitor This long comment was added to the page to prevent it being listed on Special Shortpages. It and the accompanying monitoring template were generated via Template Longcomment. Please do not remove the monitor template without removing the comment as well. ... more details
Unreferenced date December 2009 Image membrane mirror.jpg right thumb 300px Artist s conception of membrane mirror closed right and opened. US Air Force image Membrane mirror s are mirror s made on thin film s of material, such as metallized PET film biaxially oriented PET film . They can be used as components in adaptive optics systems . See also Solar sail DEFAULTSORT Membrane Mirror Category Spacecraft propulsion Optics stub ... more details
An interosseous membrane is a broad and thin plane of fibrous tissue that separates many of the bone s of the body. It is an important component of many joints . Interosseous membranes in the human body Interosseous membrane of the forearm Interosseous membrane of the leg External links DukeOrtho interosseous membrane SUNYAnatomyFigs 10 06 10 Gray s Joints Category Skeletal system musculoskeletal stub hr Me uko tana opna it Membrana interossea th ... more details
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