vitelline circulation — noun circulation of blood between the embryo and the yolk sac • Hypernyms: ↑circulation … Useful english dictionary
vitelline circulation — the circulation through the blood vessels of the yolk sac … Medical dictionary
Vitelline arteries — Infobox Embryology Name = PAGENAME Latin = GraySubject = GrayPage = Caption = Model of human embryo 1.3 mm. long. (Vitelline arteries not shown, but vitelline arteries labeled at center left.) Caption2 = System = CarnegieStage = 13 Days = 28… … Wikipedia
Vitelline veins — 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.) Gray s … Wikipedia
Yolk sac — Not all yolk has to do with birds eggs. Human embryos have a yolk sac, a membrane outside the embryo but connected by a tube (the yolk stalk) though the umbilical opening to the embryos midgut. The yolk sac serves as an early site for … Medical dictionary
sac — 1. A pouch or bursa. SYN: saccus [TA]. SEE ALSO: sacculus. 2. An encysted abscess at the root of a tooth. 3. The capsule of a tumor, or envelope of a cyst. [L. saccus, a … Medical dictionary
Yolk sac — Infobox Embryology Name = Yolk sac Latin = GraySubject = 11 GrayPage = 54 Caption = Human embryo of 2.6 mm. Caption2 = Human embryo from thirty one to thirty four days System = CarnegieStage = 5b Days = 9 Precursor = endoderm GivesRiseTo =… … Wikipedia
RÉSERVES PHYSIOLOGIQUES - Réserves animales — Alors que les besoins nutritionnels, et surtout les besoins énergétiques, des animaux sont permanents, leur alimentation est au contraire discontinue. La mise en réserve temporaire est donc une nécessité vitale. Les composés mis en réserve… … Encyclopédie Universelle
animal development — Introduction the processes that lead eventually to the formation of a new animal starting from cells derived from one or more parent individuals. Development thus occurs following the process by which a new generation of organisms is produced by … Universalium
EMBRYOGENÈSE ANIMALE — Chez les animaux, l’œuf est une cellule unique, souvent de grande dimension, à noyau digamétique, c’est à dire formé par l’assemblage des noyaux des cellules reproductrices ou gamètes. Le cytoplasme cellulaire renferme des réserves plus ou moins… … Encyclopédie Universelle