PSB-2000 Lecture Notes - Lecture 15: Thalamus, Sensory Neuron, Vasopressin
Document Summary
All steroid hormones are made from cholesterol: estrogen, testosterone, corisol-stress, progesterone, aldosterone-salt, pregnenolone- reproducion. They can leak out of the brain and cross the blood brain barrier. Testosterone and estrogen are the major sex hormones: estrogen is made from testosterone, both genders have both hormones but the levels are diferent. Testosterone and estrogen are responsible for many acivaional efects: this includes secondary sex characterisics, they are mostly released from the gonads. The sry gene is usually what determines physical sex: sry gene present: male, sry gene absent: female. Everybody has the geneic program to be f or m. Release of t by testes acivates the male program. The early embryo has two reproducive duct systems. The wolian system becomes the male tract: develops in the presence of testosterone, degenerates in the absence of testosterone. The mullerian system becomes the female tract: develops in the absence of testosterone, degenerates in the presence of amh.
