Which of the following is not part of the mammalian male reproductive organ?

Analyze the question: You are asked to find the structure that is NOT part of the male reproductive system in mammals.

Explain the concept: The mammalian male reproductive system produces and transports sperm. Its main parts are:

• Testis (testes): produce sperm and the hormone testosterone.
• Epididymis: a coiled tube on each testis where sperm mature and are stored.
• Vas deferens (sperm duct): carries sperm from the epididymis to the urethra.
• Accessory glands: seminal vesicles, prostate gland and Cowper's glands, which add fluid to form semen.
• Urethra and penis: carry semen (and urine) out of the body.

The vulva is the external genital part of the female reproductive system. It includes the labia and the opening of the vagina.

Solution, option by option:

• A. Epididymis: male, so it is part of the system.
• B. Vas deferens: male, so it is part of the system.
• C. Testis: male, so it is part of the system.
• D. Vulva: female, so it is NOT part of the male system.

Answer: D. Vulva

Tip: Group the structures by sex. Words like "testis", "epididymis", "vas deferens" and "prostate" go with males. "Vulva", "vagina", "ovary" and "uterus" go with females. In "not part of" questions, look for the odd one out.