loading...| Preferred Name |
yolk sac |
| Synonyms |
saccus vitellinus vesicula umbilicalis |
| Definitions |
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]. |
| ID |
http://purl.obolibrary.org/obo/UBERON_0001040 |
| database_cross_reference |
EMAPA:16085 EHDAA2:0002212 EFO:0003078 SCTID:362845002 CALOHA:TS-1130 VHOG:0000830 Wikipedia:Yolk_sac FMA:87180 UMLS:C0043425 GAID:1301 BTO:0001471 MESH:D015017 NCIT:C14128 EHDAA:164 |
| 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]. |
| depicted by |
http://upload.wikimedia.org/wikipedia/commons/1/17/Gray22.png |
| editor note |
consider splitting class |
| has developmental contribution from | |
| has_obo_namespace |
uberon |
| has_related_synonym |
saccus vitellinus vesicula umbilicalis |
| id |
UBERON:0001040 |
| in_subset |
http://purl.obolibrary.org/obo/uberon/core#uberon_slim |
| label |
yolk sac |
| notation |
UBERON:0001040 |
| prefLabel |
yolk sac |
| UBPROP_0000001 |
the extraembryonic tissue membrane, formed from the visceral endoderm and the extraembryonic mesoderm, which is located ventral to the embryonic disc and is connected to the presumptive midgut of the embryo; the yolk that it contains is the site of embryonic hematopoiesis and vitelline circulation is involved in early embryonic circulation; it is the origin of the primordial germ cells One of the extraembryonic fetal membranes that balloons out from the fetal midgut. [TFD][VHOG] |
| UBPROP_0000003 |
Structures homologous to the four extraembryonic membranes of reptiles and birds appear in mammals: amnion, chorion, yolk sac, and allantois.[well established][VHOG] |
| UBPROP_0000008 |
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)] |
| subClassOf |
http://purl.obolibrary.org/obo/UBERON_0005631 |