A membranous sac attached to an embryo, providing early nourishment in the form of yolk in bony fishes, sharks, reptiles, birds, and primitive mammals
membranous structure that functions as the circulatory system in mammal embryos until the heart becomes functional
membranous structure enclosing the yolk of eggs in birds reptiles marsupials and some fishes; circulates nutrients to the developing embryo membranous structure that functions as the circulatory system in mammal embryos until the heart becomes functional
thin membrane which surrounds the yolk of an egg and supplies nutrients to the embryo (in mammals, the yolk sac ceases to function when the placenta forms)
A membranous sac attached to an embryo, providing early nourishment in the form of yolk in bony fishes, sharks, reptiles, birds, and primitive mammals and functioning as the circulatory system of the human embryo before internal circulation begins
membranous structure enclosing the yolk of eggs in birds reptiles marsupials and some fishes; circulates nutrients to the developing embryo
yolk sac
الواصلة
yolk Sac
التركية النطق
yōk säk
النطق
/ˈyōk ˈsak/ /ˈjoʊk ˈsæk/
علم أصول الكلمات
[ 'yOk, 'yelk (in cultivated ] (noun.) before 12th century. Middle English yolke, from Old English geoloca, from geolu yellow; more at YELLOW.