Definitions
There are 2 meanings of the phrase
Yolk Sac.
Yolk Sac - as a noun
Membranous structure that functions as the circulatory system in mammalian embryos until the heart becomes functional
Synonyms (Exact Relations)
umbilical vesiclevesicula umbilicusvitelline sacMembranous structure enclosing the yolk of eggs in birds, reptiles, marsupials, and some fishes; circulates nutrients to the developing embryo
Example Sentences
"The yolk sac provides nutrients to the developing embryo in eggs of many animals."
"The yolk sac is an important site for blood cell development in fish embryos."
"During early pregnancy, the human embryo relies on the yolk sac for nourishment."
"In reptiles, the yolk sac contributes to the growth and development of the embryo."
"The size of the yolk sac in bird eggs can determine the health of the developing chick."
