Male Reproductive System Overview

Primary Anatomical Structures

• Testes
• Ductus deferens (Vas deferens)
• Seminal vesicles
• Urethra
• Prostate gland
• Bulbourethral glands
• Penis

Testes

• Function: Responsible for sperm development; primary sex organ for males.
• Structure: Contains seminiferous tubules where spermatogonia develop into mature sperm.
  • Sperm components:
    • Head: Contains haploid DNA (23 chromosomes).
    • Neck: Houses mitochondria for ATP production.
    • Tail (Flagellum): Propels sperm during ejaculation.
• Temperature Requirement: 34°C for sperm development, 3°C below body temperature.
• Vascular Supply: Gonadal arteries and veins.
  • Arterial supply from abdominal aorta.
  • Veins:
    • Right gonadal vein drains into inferior vena cava (IVC).
    • Left gonadal vein drains into left renal vein, then IVC.

Ductus Deferens (Vas deferens)

• Function: Transports sperm during ejaculation from epididymis to urethra.
• Historical Context: Early anatomists mistakenly thought it was a vessel.

Seminal Vesicles

• Function: Produce viscous secretion containing fructose, prostaglandins, and fibrinogen to nourish and support sperm.
• Contribution to Ejaculate: Major component, provides nutrients and helps decrease vaginal acidity.

Urethra

• Functions:
  • Conduit for urine from bladder.
  • Pathway for semen during ejaculation.
• Sections:
  • Prostatic urethra
  • Membranous urethra
  • Spongy (Penile) urethra

Prostate Gland

• Function: Produces prostate fluid to support sperm motility.
• Health Indicator: PSA levels used to diagnose and monitor prostate cancer.

Bulbourethral Glands (Cowper's Glands)

• Function: Secrete lubrication into the urethra during erection, reducing friction and neutralizing acidity.

Penis

• Structures:
  • Corpora cavernosa: Erectile tissue for erection.
  • Corpus spongiosum: Surrounds urethra, maintains open lumen.
• Function: Main copulatory organ, sensory pleasure.

Semen

• Composition: Contributions from testes, seminal vesicles, prostate gland, and bulbourethral glands.
  • Sperm from testes.
  • Nutrients and alkaline secretions from seminal vesicles.
  • Enzymes and glycoproteins from prostate gland.
  • Lubrication from bulbourethral glands.