Male Reproductive System

Anatomical Views

• Anterior View: Front view of the male reproductive system.
• Posterior View: Back view (opposite of anterior).
• Sagittal View: Side view, created by slicing down the middle and focusing on one side (right side in this case).

Key External Structures

• Visible Structures: Penis and scrotum (contains testes).

Organs and Functions

Testes

• Paired Organs: Central to male reproductive system.
• Functions:
  • Spermatogenesis: Production of sperm, requires a slightly lower temperature than core body temperature.
  • Testosterone Production: Responsible for secondary sexual characteristics (hair growth, muscle growth, voice deepening).
• Temperature Regulation:
  • Scrotum: Fleshy sac that holds testes outside the body.
  • Muscles Involved:
    • Cremaster Muscle: Raises testes in response to cold.
    • Dartos Muscle: Assists in temperature regulation.
  • Cremasteric Reflex: Reflex contraction of the cremaster muscle when lightly touched on the inner thigh.

Epididymis

• Location: Sits on top of the testes.
• Function:
  • Sperm maturation and storage.
  • Adds mitochondria and flagella to sperm for energy and motility.

Vas Deferens

• Function: Transports sperm from epididymis to urethra.
• Location: Runs behind the bladder.
• Spermatic Cord: Contains vas deferens, artery, and vein serving the testes.

Accessory Glands

Seminal Vesicles

• Location: Behind the bladder.
• Contribution: Provides alkaline fluid rich in fructose, making up 60% of semen volume.

Prostate Gland

• Contribution: Produces prostatic fluid to enhance sperm motility.

Bulbourethral Glands

• Location: Two glands, one on each side of the penis.
• Contribution: Produces lubricant for urethra and vagina.

Sperm Journey

• Urethra: Channel for semen to exit the body.
• Role of Penis: Penetrates the vagina to deposit sperm inside during reproduction.

Terminology

• Semen: Combination of sperm and fluid from accessory glands.
• Alkaline Semen: Neutralizes acidic environments of male urethra and vagina for sperm survival.

Key Points

• Temperature regulation is crucial for sperm production.
• Sperm maturation involves gaining energy capacity and mobility features.
• Accessory glands provide necessary fluids for sperm viability and mobility.