GRS4101 Lecture Notes - Lecture 1: Spermatocyte, Phagocytosis, Cytochrome C Oxidase Subunit Ii
24 Jul 2018
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Reproductive function: gonads and gametes also see notes from 2212. Testes begin in the abdomen, proximal to the kidney, descends into scrotum via the inguinal canal testes covered in fibrous capsule called the tunica albuginea: divides testes into around 250 different lobules (1-4 semi t) Testis function: gamete production (seminiferous tubules epithelium, androgen secretion (interstitial tissue leydig cells) Seminiferous tubules: sertoli cells and germ cells: mature: proliferation of germ cells; sertoli cells = 10%. Sertoli cells: do not regenerate in adult life, cannot be replaced if exposed to toxins. Protect spermatocyte/spermatids from autoimmune response, prevent toxins entering tubules ( blood-testis barrier: tight junctions between sertoli cells) Phagocytosis of residual cytoplasm during spermatogenesis: release of mature spermatids into lumen of tubule (spermiaton) Secretory- androgen binding (abp), amh, inhibin (inhibits fsh); paracrine glands. Spermatogenesis: mitosis of germ cell: primary spermatocyte: meiosis i. 1st meiotic division: takes 22 days, 2nd in a matter of hours. Stem cells enter into spermatogenesis every 16 days.
