[ANSC 3080] - Final Exam Guide - Everything you need to know! (41 pages long)

442 views41 pages

Document Summary

What is sex: need for two individuals produce germ cells which fuse to produce an offspring, difference (sexual dimorphism) carried by genes= sex chromosomes. Birds: zw- f zz- m: during early fetal life, gonads are differentiated. Embryo sex differentiation: formation of primordial germ cells (pgcs) Circulate the genital ridge to form indifferent gonads: differentiation of cortex into ovary or medulla into testis- testis organization through transient expression of genes (tdf) from sry. Hypothalamus has two centres of gnrh neutrons (tonic center- responsible for basal secretion; surge centre responsible for ovulatory cycles for female behaviour. During perinatal period: estradiol released by placenta and embryonic adrenals binds to a carrier in blood and does not enter the brain, presence of estradiol in the brain in activates the surge center= male brain. Testes need to be kept 4-6 c below temperature for spermatogenesis. During late part of gestation or early life: testicular descent via inguinal canal is required.