overlaps overlaps in taxon develops from develops from has developmental contribution from has developmental contribution from Amniota cloaca endoderm renal system allantois http://upload.wikimedia.org/wikipedia/commons/a/a5/Gray25.png Wikipedia:Allantois UMLS:C0002084 RETIRED_EHDAA2:0000114 EMAPA_RETIRED:16084 NCIT:C34101 VHOG:0000738 BTO:0000474 allantoic SCTID:308825007 allantoic bud UBERON:0004340 EHDAA2:0001504 EMAPA:16107 a diverticulum of the hindgut endoderm [ISBN:0073040584 (Vertebrates, Kardong)] Structures homologous to the four extraembryonic membranes of reptiles and birds appear in mammals: amnion, chorion, yolk sac, and allantois.[well established][VHOG] part_of embryo in EHDAA2 - note differences in humans A membranous sac that develops from the posterior part of the alimentary canal in the embryos of mammals, birds, and reptiles, and it is important in the formation of the umbilical cord and placenta in mammals[VHOG]. A membranous sac that develops from the posterior part of the alimentary canal in the embryos of mammals, birds, and reptiles, and it is important in the formation of the umbilical cord and placenta in mammals. [TFD][VHOG] MESH:D000482 splanchnic layer of lateral plate mesoderm extraembryonic membrane