The part of the male reproductive organ where sperm cells are produced is called?

Analyze the question: It asks where sperm cells are produced (not stored, carried or added to).

Concept: Sperm production is called spermatogenesis. It takes place in the testes, inside tightly coiled tubes called the seminiferous tubules. The cells lining these tubules divide by meiosis to form sperm cells.

Going through the options:

• A. Epididymis: A coiled tube on the surface of each testis. Sperm are stored and mature here, but they are not made here.
• B. Penis: The organ that delivers semen into the female reproductive tract. It does not produce sperm.
• C. Seminal vesicle: A gland that produces a fluid rich in fructose, which nourishes the sperm. It does not make sperm.
• D. Seminiferous tubules: The site of sperm production inside the testes. This is correct.
• E. Vas deferens: The tube that carries sperm from the epididymis toward the urethra. It only transports sperm.

Answer: D, seminiferous tubules.

Tip: Remember the word "seminiferous", which means "semen-bearing" or "seed-producing". Then use this sequence:

• Made in the seminiferous tubules
• Stored in the epididymis
• Carried by the vas deferens
• Fed by the seminal vesicle and other glands
• Delivered by the penis