Describe the head and tail region of the spermatozoan. Understand the relationship among the hypothalamus, pituitary, and interstitial cells of the testis. Paired ovoid glands suspended by spermatic cords within scrotum. At the posterior pole of the testis, the tunica albuginea thickens to form the mediastinum testes through which blood and lymphatic vessels and nerve fibers enter and leave testes. This connective tissue septa radiate from the mediastinum into the parenchyma to form 250 lobules per testis which contain the sperm-producing seminiferous tubules.
Cells have a large, oval-shaped nucleus with a prominent nucleolus.
Their cytoplasm contains the usual organelles plus abundant SER and bundles of microfilaments. The tight junctions divide the seminiferous tubule into a basal compartment which extends from the basal lamina to the Sertoli cell tight junctions and an adluminal compartment which extends from the tight junctions to the lumen of the seminiferous tubule. Developing sperm cells occupy deep recesses in the lateral surfaces of Sertoli cells. The tight junctions form part of the blood-testis barrier. ABP binds and concentrates testosterone.