Explanation

FSH and LH. Hormonal Control of Spermatogenesis Spermatogenesis is initiated due to the increase in Gonadotropin Releasing Hormone ($GnRH$) by hypothalamus. $GnRH$ acts on the anterior lobe of the pituitary gland to secrete Luteinising Hormone (LH) and Follicle Stimulating Hormone (FSH). LH acts on the Leydig cells of the testis to secreted testosterone. FSH acts on the sertoli cells of the seminiferous tubules of the testis to secrete an androgen binding protein (ABP) and inhibin. ABP concentrates testosterone in the seminiferous tubules. Inhibin suppresses FSH synthesis. FSH act on spermatogonia to stimulate sperm production [image:3_image91.emf] Dark line – Positive feed back Dot line – Negative feed back