The Male Reproductive System | Biology Class 12 - NEET PDF Download

Location and Components

• The male reproductive system is found in the pelvis and comprises a pair of testes along with accessory ducts, glands, and external genitalia.
• The testes are located outside the abdominal cavity in a pouch called the scrotum, which helps maintain a temperature 2–2.5°C lower than the normal body temperature, essential for sperm production.

Diagrammatic sectional view of male pelvis showing reproductive system

Testes Structure

• Each testis is oval-shaped, measuring about 4 to 5 cm in length and 2 to 3 cm in width.
• The testis is covered by a dense covering and contains approximately 250 compartments called testicular lobules.

Testes Structure in Detail

• Each lobule houses one to three seminiferous tubules, where sperm are produced.
• These tubules are lined with male germ cells(spermatogonia) and Sertoli cells.
• The germ cells undergo meiosis to form sperm, while Sertoli cells provide nutrients to the germ cells.

Diagrammatic sectional view of seminiferous tubule

• The spaces between the tubules, called interstitial spaces, contain small blood vessels and Leydig cells, which produce androgens, a type of testicular hormone.

Accessory Ducts

 Male reproductive system (part of testis is open to show inner details) and Accessory Ducts

• The male sex accessory ducts include the rete testis, vasa efferentia, epididymis, and vas deferens.
• The seminiferous tubules connect to the vasa efferentia through the rete testis.
• The vasa efferentia lead to the epididymis, located on the posterior surface of each testis.
• The epididymis connects to the vas deferens, which ascends into the abdomen, loops over the urinary bladder, and eventually opens into the urethra as the ejaculatory duct.

Urethra and Penis

Urethra and Penis

• The urethra originates from the urinary bladder and extends through the penis to its external opening, the urethral meatus.
• The penis, the male external genitalia, is made of special tissue that enables erection to facilitate insemination.
• The enlarged end of the penis, called the glans penis, is covered by a loose fold of skin known as the foreskin.

Accessory Glands

Accessory Glands of Male Reproductive system

• The male accessory glands include seminal vesicles, prostate, and bulbourethral glands.
• Their secretions form the seminal plasma, which is rich in fructose, calcium, and various enzymes.
• The secretions from the bulbourethral glands also aid in the lubrication of the penis.