- The primary sex organs of the male; they produce sperm and hormones.
- Their anatomical position "outside" of the body reflects a physiologic necessity: spermatogenesis (formation of sperm) requires a temperature slightly lower than that of the body.
Tunica albuginea
- Fibrous outer surface of the testis
Mediastinum of the testis
- Where the tunica albuginea forms a thickened ridge along the posterior aspect.
- Septa extend from the mediastinum, which separate the lobules.
Seminiferous tubules
- Lie within the lobules
- Sites of sperm production.
- Specialized cells within the lobules produce hormones that support sperm maturation.
Straight tubules
- Transport sperm from the seminiferous tubules to the rete testis
Rete testis
- Comprises a network of tubules within the mediastinum of the testis.
Efferent ductules
Epididymis
- Stores developing sperm
- Head comprises the tightly coiled merger of the efferent ductules
- Body comprises a singular long coiled duct
- Tail of the epididymis is continuous with ductus deferens
Ductus deferens
- Transports sperm to ejaculatory duct
Tunica vaginalis
- Double-layered sac that comprises a visceral layer, which is closely adhered to the tunica albuginea of the testis, and, a parietal layer, which is in contact with the innermost layer of the scrotum and spermatic cord.
- The cavity of the tunica vaginalis is the space between these two layers, and contains a small amount of fluid, which allows for movement of the testicles within the scrotum.