Membranous structure that functions as the circulatory system in mammalian embryos until the heart becomes functional
English: yolk sac, vitelline sac, umbilical vesicle, vesicula umbilicus
yolk_sacEnglish
yolk sac, umbilical vesicle, vesicula umbilicus, vitelline sac
Noun
Membranous structure enclosing the yolk of eggs in birds, reptiles, marsupials, and some fishes, circulates nutrients to the developing embryo
English: yolk sac