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Male Reproductive System Diagram — Labeled for NEET Biology

The male reproductive system is the organ system responsible for producing, storing, and delivering spermatozoa along with accessory gland secretions for reproduction. It is important for NEET Biology because NTA frequently tests spermatogenesis, testosterone production by Leydig cells, accessory gland functions, and sperm structure.

Urinary BladderUrinarybladderSeminalvesicleVas deferens(Ductus deferens)Testis(Seminiferous tubules)EpididymisProstateglandCowper's gland(Bulbourethral)UrethraPenisTestisEpididymisTestesEpididymisVas deferensSem. ves.ProstateCowper'sUrethraPenisBladder

Parts of the Male Reproductive System and Their Functions

Testes

Primary male reproductive organs (gonads) located in the scrotum. Produce spermatozoa and secrete testosterone. Each testis contains about 250 lobules with seminiferous tubules.

Seminiferous Tubules

Highly coiled tubules inside testes where spermatogenesis occurs. Lined with spermatogonia (germ cells) and Sertoli cells (nurse cells) that provide nutrition to developing sperm.

Epididymis

Coiled tube on the posterior surface of each testis. Stores spermatozoa and allows them to mature and gain motility. Connects testis to vas deferens.

Vas Deferens

Long muscular duct that transports mature sperm from epididymis to the ejaculatory duct. Passes through the inguinal canal into the abdominal cavity.

Seminal Vesicle

Paired lobulated glands that secrete an alkaline fluid rich in fructose (energy source for sperm), prostaglandins, and clotting proteins. Contributes ~60% of semen volume.

Prostate Gland

Single large gland surrounding the urethra below the bladder. Secretes a slightly acidic fluid with citric acid, lipids, and proteolytic enzymes that activate sperm.

Cowper’s Gland (Bulbourethral)

Paired pea-sized glands below the prostate. Secrete a clear, alkaline pre-ejaculatory fluid that lubricates and neutralises urethral acidity.

Urethra

Common passage for urine and semen in males. Passes through the prostate gland and the penis. Divided into prostatic, membranous, and penile segments.

Penis

External copulatory organ containing erectile tissue (two corpora cavernosa and one corpus spongiosum). Deposits semen into the female reproductive tract.

How NTA Tests Reproduction in NEET

Spermatogenesis

Occurs in seminiferous tubules. Spermatogonia (2n) undergo mitosis, then meiosis I (primary spermatocyte → secondary spermatocyte) and meiosis II (spermatid). Spermiogenesis transforms spermatids into mature spermatozoa. Know the role of Sertoli cells in nourishment.

Testosterone Production (Leydig Cells)

Interstitial cells of Leydig, located between seminiferous tubules, secrete testosterone under LH stimulation. Testosterone controls development of secondary sexual characters, spermatogenesis, and male accessory glands.

Accessory Gland Secretions

Seminal vesicles secrete fructose (energy for sperm). Prostate secretes enzymes and citric acid. Cowper’s glands secrete lubricating mucus. NTA tests which gland contributes which component of seminal plasma.

Sperm Structure and Function

Mature sperm has head (acrosome + nucleus), neck (centriole), middle piece (mitochondrial spiral for energy), and tail (flagellum for motility). Acrosome contains enzymes for penetrating the ovum. Know the function of each part.

Practice Reproduction PYQs on MedicNEET

Master spermatogenesis, accessory gland functions, and sperm structure with previous year questions that match NTA's exact patterns.