IMED2004 Study Guide - Final Guide: Gonad, Y Chromosome, Hermaphrodite
Document Summary
Y chr. sex determining region (sry gene) Causes indifferent gonad to develop as a testis. Other genes on autosomes play important role. Once testes develop they secrete two hormones. Females can make testosterone as an adult. Sry region on y chromosome allows expression of active testosterone and mih. Sry inhibit female reproductive organs to be generated bc of. In early embryo there are two internal duct systems. Developmental pathways activate different sets of genes. Cause undifferentiated gonads to develop as testes or ovaries. Prior to week 7, can"t see difference in sex. Either wolffian or mullerian will be expressed. > to get functional gonads and genitalia. Can be xy but cannot use testosterone bc no receptor for hormone (mutation) = look externally female, has small testes. But have ovotestis with both spermatagonia & ovarian follicles. (very rare & usually raised as female). But produce high levels of androgenic hormones. Only one of the two copies of a gene is active.
