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Vitelline
Vitelline may refer to: Embryology * Vitelline arteries, arteries that bring blood to the yolk sac * Vitelline circulation, the system of blood flowing between an embryo and its yolk sac * Vitelline cyst, a developmental defect relating to the closure of the vitelline duct * Vitelline duct, a tube that joins the yolk sac to the midgut lumen of a human embryo * Vitelline membrane, membrane surrounding an ovum * Vitelline veins, veins that drain blood from the yolk sac Birds * Vitelline masked weaver (''Ploceus vitellinus''), a species of bird endemic to Africa * Vitelline warbler (''Setophaga vitellina''), a songbird species found in the Cayman Islands and Honduras See also * Vitellin, a protein found in egg yolk * Vitelli The House of Vitelli, among other families so named, were a prominent noble family of Umbria, rulers of Città di Castello and lesser '' rocche''. History In spite of ambitious genealogies, there is no demonstrable connection with the ancient R ..., a su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vitelline Cyst
Vitelline may refer to: Embryology * Vitelline arteries, arteries that bring blood to the yolk sac * Vitelline circulation, the system of blood flowing between an embryo and its yolk sac * Vitelline cyst, a developmental defect relating to the closure of the vitelline duct * Vitelline duct, a tube that joins the yolk sac to the midgut lumen of a human embryo * Vitelline membrane, membrane surrounding an ovum * Vitelline veins, veins that drain blood from the yolk sac Birds * Vitelline masked weaver (''Ploceus vitellinus''), a species of bird endemic to Africa * Vitelline warbler (''Setophaga vitellina''), a songbird species found in the Cayman Islands and Honduras See also * Vitellin, a protein found in egg yolk * Vitelli The House of Vitelli, among other families so named, were a prominent noble family of Umbria, rulers of Città di Castello and lesser '' rocche''. History In spite of ambitious genealogies, there is no demonstrable connection with the ancient R ..., a su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vitelline Membrane
The vitelline membrane or vitelline envelope is a structure surrounding the outer surface of the plasma membrane of an ovum (the oolemma) or, in some animals (e.g., birds), the extracellular yolk and the oolemma. 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 mammals. Between the vitelline membrane and zona pellucida is a fluid-filled perivitelline space. 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 vitelline membrane through exocytosis of the cortical granules, transforming it into a hard layer called the “fertilization membrane”, which serves as a bar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vitelline Veins
The vitelline veins are veins that drain blood from the yolk sac and the gut tube during gestation. 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. Beyond this, they 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. This is 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 * Inferior mesenteric vein The branches conveying the blood to the plexus are named the venae advehentes, and become the branches of the po ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vitelline Masked Weaver
The vitelline masked weaver (''Ploceus vitellinus'') is a species of bird in the family Ploceidae. It is found in western, central and eastern Africa. Gallery Vitelline masked weaver (Ploceus vitellinus peixotoi) male.jpg, male ''P. v. peixotoi''São Tomé and Príncipe Vitelline masked weaver (Ploceus vitellinus peixotoi) male nest building.jpg, male ''P. v. peixotoi'' nest buildingSão Tomé and Príncipe São Tomé and Príncipe (; pt, São Tomé e Príncipe (); English: " Saint Thomas and Prince"), officially the Democratic Republic of São Tomé and Príncipe ( pt, República Democrática de São Tomé e Príncipe), is a Portuguese-speaking i ... References External links Vitelline masked weaver- Species text in Weaver Watch. vitelline masked weaver Birds of Sub-Saharan Africa vitelline masked weaver Taxonomy articles created by Polbot {{Ploceidae-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vitelline Warbler
The vitelline warbler (''Setophaga vitellina'') is a songbird species in the New World warbler family (Parulidae). It is found in the Cayman Islands and on the Swan Islands in Honduras. Taxonomy This species is part of the large New World warbler genus Setophaga. Currently, there are three subspecies described: *''S. v. nelsoni'', (Bangs, 1919), Swan Islands *''S. v. vitellina'', (Cory, 1886), Grand Cayman Island *''S. v. crawfordi'', (Nicoll, 1901), Little Cayman and Cayman Brac These subspecies differ noticeably in underpart coloration and head patterning. Some taxonomists have considered this species conspecific with the North American prairie warbler. However, a genetic study confirmed its species status, while reaffirming a close relationship between the two species. Description This species bears a stark resemblance to the prairie warbler, sharing its streaking on the belly, yellow-green back, and subtle yellow wingbars, differing with the intensity of the black streaks. I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vitelline Duct
In the human embryo, the vitelline duct, also known as the vitellointestinal duct, the yolk stalk, the omphaloenteric duct, or the omphalomesenteric duct, is a long narrow tube that joins the yolk sac to the midgut lumen of the developing fetus. 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). Function 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. About two percent 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 typically situated within two feet of the ileocecal junction and may be attached by a fibrous cor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vitelline Arteries
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 In human anatomy, the inferior mesenteric artery, often abbreviated as IMA, is the third main branch of the abdominal aorta and arises at the level of L3, supplying the large intestine from the distal transverse colon to the upper part of the ana .... References External links * * https://web.archive.org/web/20070623132305/http://isc.temple.edu/marino/embryology/Heart98/heart_text.htm * * https://web.archive.org/web/20070915072304/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 * https://web.archive.org/web/20070812190309/http://www.m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vitelline Circulation
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 is 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 vitelline arteries (a branch of the dorsal aorta), and after circulating through a wide-meshed capillary plexus, is returned by the vitelline veins The vitelline veins are veins that drain blood from the yolk sac and the gut tube during gestation. 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. B ... 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 th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vitellin
Vitellin is a protein found in the egg yolk. It is a phosphoprotein. Vitellin is a generic name for major of many yolk proteins. Vitellin has been known since the 1900s. The periodic acid-Schiff method and Sudan black B dye was used to help determine that Vitellin is a glycolipoprotein because it stained positive when tested. This protein was found to weigh ~540 kDa, given the weight of each of its 4 major subunits. Vitellin is essential in the fertilization process, and embryonic development in egg-laying organisms. This phosphoprotein acts as a membrane, 1-3.5μm, that encloses the egg that comprises at least five glycoproteins that resemble the zona pellucida evident in mammalian organisms. When the egg is fertilized, it buds off from the gamete surface, which results in the fertilization of the membrane in most invertebrates, amphibians, birds, and fishes. During fertilization, the acrosome of the sperm interacts with the vitelline envelope that has species-specific recogniti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |