part_of part of part of develops_from develops from male reproductive system testis http://upload.wikimedia.org/wikipedia/commons/c/c3/Gray1144.png orchis EHDAA2:0002007 BILA:0000124 EHDAA:8146 (...) while it is likely that Urbilateria lacked a complex somatic reproductive system, it is at present impossible to speculate on whether or not it possessed a true gonad, let alone any other somatic adaptations for reproduction (reference 1); Examination of different vertebrate species shows that the adult gonad is remarkably similar in its morphology across different phylogenetic classes. Surprisingly, however, the cellular and molecular programs employed to create similar organs are not evolutionarily conserved (reference 2).[uncertain][VHOG] uberon The testes are descended in metatherian and eutherian mammals, first transabdominally, then inguinoscrotally MA:0000411 MIAA:0000132 testiculus FBbt:00004928 testes CALOHA:TS-1030 EV:0100102 EMAPA:17972 TAO:0000598 gonad of male reproductive system MESH:D013737 ZFA:0000598 UBERON:0000473 testicular galen:Testis NCIT:C12412 Wikipedia:Testis GAID:396 FMA:7210 VHOG:0000252 XAO:0000157 HAO:0001007 EFO:0000984 SCTID:181431007 MAT:0000132 WBbt:0006794 testicle A gonad of a male animal. A gonad produces and releases sperm. male gonad BTO:0001363 gonad of male genitalia UMLS:C0039597 Male reproductive organ.[TAO] AAO:0000606 BSA:0000085 OpenCyc:Mx4rvVjM25wpEbGdrcN5Y29ycA UBERON:0002117 gonad reproductive organ male reproductive organ indifferent gonad