part of part of cloaca A cloaca is apparently a primitive vertebrate feature because it occurs in most primitive gnathostomes and persists in the embryos of almost all vertebrates.[well established][VHOG] A common passage for fecal, urinary, and reproductive discharge in most lower vertebrates as well as the terminal end of the hindgut before division into rectum, bladder, and genital primordia in mammalian embryos. [TFD][VHOG] AAO:0000095 Anatomical structure which is the common receptacle for the alimentary canal, Wolffian ducts, oviducts, and the bladder.[AAO] Common chamber into which the intestines and excretory system opens. Arises during development in all vertebrates, but in many it becomes subdivided, lost or incorporated into other structures GAID:1206 Human beings only have an embryonic cloaca, which is split up into separate tracts during the development of the urinary and reproductive organs MESH:D002988 UBERON:0000162 UMLS:C0008987 VHOG:0001186 XAO:0000244 ZFA:0005781 adding df link to embryonic cloaca leads to a cycle in uberon-simple, as cloaca is a suberclass of embryonic cloaca cloacal cloacal chamber hindgut endoderm and proctodeal ectoderm. uberon vent digestive tract mesoderm-derived structure genitourinary system subdivision of tube