overlaps develops from has developmental contribution from cloaca endoderm renal system allantois Wikipedia:Allantois UBERON:0004340 RETIRED_EHDAA2:0000114 EMAPA_RETIRED:16084 EHDAA2:0001504 EMAPA:16107 NCIT:C34101 VHOG:0000738 BTO:0000474 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]. SCTID:308825007 allantoic bud MESH:D000482 splanchnic layer of lateral plate mesoderm extraembryonic membrane