L3.2.5: External Genitalia

• External genitalia

  • Scrotum
  • Penis
• Scrotum

  ● Divided sac of skin that hangs outside the abdominal cavity, between the legs and at the root of the penis

  ● Provides a temperature about 3°C (5.4 °F) lower than body temperature.

  ➔ Necessary for healthy sperm
• Penis

  ● Male organ of copulation (sexual penetration) that delivers sperm to the

  female reproductive tract

  ● Has 3 regions:

  1. Shaft (Body of penis)
  2. Glans penis (Enlarged tip)
  3. Prepuce

  ➔ Folded cuff or skin around the proximal end of the glans penis

  ➔ Surgically removed by procedure of circumcision
• Spongy (Penile) Urethra and Its Role in Erection

  ● Internally, the spongy urethra is surrounded by 3 elongated areas of erectile tissue

  (1) Corpora Cavernosa

  (2) Corpus Spongiosum

  (3) Spongy Urethra

  ● Erection happens when this erectile tissue fills with blood during sexual excitement causing:

  ➔ An enlarged and stiffened penis

  ➔ Lets penis serve as the organ for copulation
• Scrotum

  ○ Sac that serves as an external covering and has a wrinkled appearance

  ○ Protects and surrounds the testes and provides enough covering to promote thermoregulation.

  ○ Maintains testes at 3°C lower than the normal body temperature.
• Penis

  ○ Delivers the sperm to the female reproductive tract.

  ○ Copulation and urination

  ○ Regions of the penis:

  ■ Shaft (corpus): spongy tissue

  ■ Glans penis: highly sensitive

  ■ Prepuce (foreskin): folded cuff of the skin; covers the glans

  ○ Internally, there are three areas of spongy erectile tissue around the urethra.

  ○ Erections occur when this erectile tissue fills with blood during sexual excitement.

  ○ Capability of Erection is brought by vasocongestion or increased presence of blood.