Male Reproductive System I ppt..

• The male reproductive system is composed of the testes ,genital ducts, accessory glands ,and penis .
• Testes function in the production of hormones and spermatozoa. Testosterone is the main hormone produced in the testes .
• Testosterone is important for spermatogenesis, sexual differentiation during embryonic and fetal development, and control of gonadotropin secretion. Dihydrotestosterone acts on many organs and tissues of the body during pubety and adulthood (eg , muscle, hair pattern, and hair growth.
• The genital ducts and accessory glands produce secretions and aided by smooth muscle contractions, propel spermatozoa toward the exterior.
• These secretions also provide nutrients for spermatozoa while they are confined to the male reproductive tract.
• Spermatozoa and the secretions of the genital ducts and Accessory glands make up the semen ,which is introduced into the female reproductive tract through the penis.

Testes:
• Each testis (testicle) is surrounded by a capsule of dense connective tissue, the tunica albuginea , is thickened on the posterior side of the testis to form the mediastinum testis, from which fibrous septa penetrate the organ and divide it into about 250 pyramidal compartments or testicular lobules (fig.1).
• The septa are incomplete, and there is intercommunication between lobules. Each lobule is occupied by one to four seminiferous tubules that are surrounded by interstitial loose connective tissue rich in blood and lymphatic vessels, nerves, and endocrine interstitial cells(Leydig cells) which secrete testosterone .
• Seminiferous tubules produce male reproductive cells ,the spermatozoa , whereas interstitial cells secrete testicular androgens.
• The testes are suspended within the two sides of the secrotum at the ends of the spermatic cords .
• Because of the migration from the abdominal cavity each testis carries with it a serous sac, the tunica vaginalis (fig .1), derived from the peritoneum.
• The tunic consists of an outer parietal layer lining the scrotum and an inner visceral layer, covering the tunica albuginea on the anterior and lateral sides of the testis.