PSB-2000 Lecture Notes - Lecture 17: Mesonephric Duct, Paramesonephric Duct, Secondary Sex Characteristic
Document Summary
Sex steroids hormones are released by the gonads. 3 classes: androgens: testosterone, dht (dihydro testerone, estrogen: estradiol (specific hormone, progestins: progesterone. Pathway of synthesis: cholesterol progesterone testosterone to either . 5 alpha reductase: changes testosterone to dht. Effects of hormone: organizational/developmental: occurs during a critical period of development and differentiates between the sexes. They are permanent: activational: triggering reproduction-related behavior in mature individuals and is temporary. Both sexes start out with the same primordial gonads. They have the potential to become an ovary (cortex-outer portion) or testis (medulla-inner portion). Y chromosome has sry (sex determining region of y chromosome). This gene triggers the synthesis of sry protein then the testes are developed: if no sry present then one begins to develop ovaries. Also have primordial versions of reproductive tracts. When one develops testes the secrete an anti-mullerian hormone and testosterone which promotes wolffian ducts and dht for development of male genitalia.
