VIBS 305 Lecture Notes - Lecture 14: Paramesonephric Duct, Inguinal Canal, Suspensory Ligament
20 Dec 2017
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Document Summary
Gender differentiation doesn"t occur until the 7th week of development. If primordial germ cells don"t migrate then the gonads will not form. Ducts of reproductive system: males/females have both ducts at some point in development. Female: mesonephric duct - open into the urogentical sinus. Paramesonephric duct - opens into the abdominal cavity. Sry gene (on y-chromosome) triggers differentiation of sertoli (sustencular) cells secrete mullerian inhibiting substance (mis) Leydig cells secrete testosterone -> stimulate mesonephric ducts to develop into the epidydimus and ductus deferens. Dht (dihydride testosterone) directs the formation of urethra, prostate, penis, prepuse*, and scrotum. Mesenchymal cord lower temperature for sperm production guides testicles into nal destination. Phase 1: transabdominal does not pull testes into scrotum testosterone causes regression of cranio- suspensory ligament. Insulin-like 3 produced by leydig causes gubernaculum to thicken movement of fetus promotes passage of the testes through the inguinal canal.
