yolk sac

saccus vitellinus

A sac-like expansion of the ventral wall of the intestine, narrowed into a yolk stalk near the body[Hyman's]. Membranous sac attached to an embryo, providing early nourishment in the form of yolk in bony fishes, sharks, reptiles, birds, and primitive mammals. It functions as the developmental circulatory system of the human embryo, before internal circulation begins. In the mouse, the yolk sac is the first site of blood formation, generating primitive macrophages and erythrocytes[WP].

Type Organ
Parent Structure extraembryonic tissue
Latin Name saccus vitellinus
FMA ID 87180

Frequently Asked Questions

What is the yolk sac?
A sac-like expansion of the ventral wall of the intestine, narrowed into a yolk stalk near the body[Hyman's]. Membranous sac attached to an embryo, providing early nourishment in the form of yolk in bony fishes, sharks, reptiles, birds, and primitive mammals. It functions as the developmental circul
What is the Latin name for the yolk sac?
The Latin name for the yolk sac is saccus vitellinus.

Related Structures

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