rectum http://upload.wikimedia.org/wikipedia/commons/7/75/Anorectum.gif uberon EV:0100081 MIAA:0000050 MAT:0000050 XAO:0000238 OpenCyc:Mx4rvVjaU5wpEbGdrcN5Y29ycA GAID:311 VHOG:0001751 EHDAA:5836 intestinum rectum MESH:A03.492.411.495.767 terminal portion of large intestine terminal portion of intestine rectal galen:Rectum EMAPA:17896 CALOHA:TS-1180 BTO:0001158 The terminal portion of the large intestine between the ileo-pelvic colon and the anus. [Dorian_AF, Elsevier's_encyclopaedic_dictionary_of_medicine, Part_B:_Anatomy_(1988)_Amsterdam_etc.:_Elsevier][VHOG] The terminal portion of the intestinal tube, terminating with the anus. AAO:0010401 EHDAA2:0001592 FMA:14544 UMLS:C0034896 UBERON:0001052 NCIT:C12390 rectal sac EFO:0000848 MA:0000336 In the lungfish, sharks and rays the rectum opens into the cloaca which also receives wastes (urine) from the kidneys and material from the reproductive organs. In bony fish the rectum reaches the outside environment through the anus, which is normally situated just in front the urinary and reproductive openings. However in some fish the digestive tract may be curled back on itself, and in the Electric Eel (Electrophorus electricus) the anus is situated in the fish's throat. -- http://www.earthlife.net/fish/digestion.html subdivision of digestive tract