Note! Male reproductive system closely related to urinary system.

PartFunction
1. Testis
(2 ovoid testes)
- Each testis produces sperm
- Each testis also produces male sex hormones → like testosterone
- Male hormones → responsible for development + maintenance of secondary sexual characteristics in males
2. Scrotum- Testis lies between thighs
- both lie in pouch like sac called scrotum
- Scrotum is outside main body cavity → thus it is at slightly lower temperature than body temp.
- lower temp → essential for sperm to develop properly.
3. Sperm Duct- Each sperm duct → loops over a ureter → and then opens into urethra
- after sperm released from testis → they travel through sperm duct.
4. Prostate Gland and its Secretions- Prostate gland → is at base → of urinary bladder → where 2 sperm ducts join the urethra
- Prostate gland → secretes a slippery fluid → which mixes with sperm.
- fluid → contains nutrients + enzymes → which nourishes sperm + stimulate them to swim actively.
- mixture of fluid + sperm = semen
5. Urethra- Tube which passes from bladder through centre of penis to outside body
- Both semen and urine pass out of body through urethra
6. Penis- Penis is an erectile organ → containing erectile tissue with numerous blood spaces.
- when blood spaces filled with blood → penis becomes erect and hard
- Penis enters vagina of woman → during sexual intercourse → to deposit semen, containing sperm

Note

Upper end of each testis → is a spermatic cord → which contains blood vessels Rotation of testis within its sac → may kink off its own blood supply → which will result in irreversible damage to the testis. Leading from the end of testis → is narrow + much coiled tube ⇒ epididymis. Epididymis → temporarily stores inactive form of sperm that is produced by testes → sperm travels from epididymis via sperm duct sperm duct from each side → passes into abdominal cavity + loops over ureter → of that side before opening into urethra

Sperm + urine do not pass thru urethra at same time


Structure of Sperm

Structure of Sperm