Preferred Label : yolk sac;
Uberon definition : 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].;
Uberon Homology note : Structures homologous to the four extraembryonic membranes of reptiles and birds appear
in mammals: amnion, chorion, yolk sac, and allantois.[well established][VHOG];
Uberon Taxon note : In therians, a structure homologous to the yolk sac is is present, but contains no
yolk platelets. Instead it is filled with fluid [ISBN:0073040584 (Vertebrates, Kardong)];
Origin ID : 0001040;
UMLS CUI : C0043425;
Currated CISMeF NLP mapping
- Semantic type(s)
- UMLS correspondences (same concept)
- Uberon cross reference
- has developmental contribution from
- has part
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].
