External Organs
• Penis- allows urine and sperm to pass. o Root, shaft, glans penis, ureteral orifice o Corpus cavernosa and corpus spongiosum become engorged o Average length is 3 inches
• Scrotum o Holds testicles
Internal Structures
• Testes- Male gonads o Functions: Sperm production and hormone production o Seminiferous tubules: Sperm production takes place
• Epididymis o Seminiferous tubules converge to form o Sperm mature
• Vas deferens o Joins ejaculatory duct with prostate gland o Site of vasectomy
• Seminal vesicle o Secrete 60% of seminal fluid
• Prostate gland o Produce 30-35% of seminal fluid
• Cowper’s (bulbouretheral) gland o Secrete clear mucus prior to ejaculation
Physiology
• Sex Hormones o Testosterone -Testes, adrenal glands
Stimulates sperm production in testes, triggers development of secondary sex characteristics, regulates sex drive o GnRH- Hypothalamus
Stimulates pituitary during sperm production o FSH- Pituitary
Stimulates sperm production in testes o ICSH (LH)- Pituitary
Stimulates testosterone production in interstitial cells within testes o Inhibin- Testes
Regulates sperm production by inhibiting release of FSH o Oxytocin- Hypothalamus, testes
Stimulates contractions in the internal reproductive organs to move the contents of the tubules forward; influences sexual response and emotional attraction o Relaxin- Prostate
Increases sperm motility
Male Cycle
• High hormone levels in the morning, lowest in the evening
• Spermatogenesis o Produces several million sperm a day o Produced in seminiferous tubules, then travel through the epididymis where they mature and become mobile.
Semen Production
• Contain sperm and seminal fluid
Male Sexual Response
• Generally ,men