Which of the choices below is NOT a function of the vagina?

A. serves as a passageway for the primary oocyte: The primary oocyte completes its first meiotic division within the follicle and is released as a secondary oocyte during ovulation. The secondary oocyte then travels through the uterine tubes, not the vagina. The vagina is located distal to the site of fertilization and zygote development.

B. receives semen from the penis during sexual intercourse: The vaginal canal serves as the copulatory organ of the female reproductive system, designed to receive the male penis. Its distensible walls and mucosal lining facilitate the deposition of sperm near the external os of the cervix. This is a critical step for natural reproduction.

C. serves as a passageway for menstrual flow: The vagina provides the exit route for the functional layer of the endometrium and blood shed during the menses. This occurs when fertilization does not take place and progesterone levels decline. It connects the uterine cavity to the external environment for this physiological discharge.

D. serves as the birth canal: During parturition, the vagina expands significantly to allow the passage of the fetus from the uterus to the outside world. Its muscular layer and rugae provide the necessary elasticity for delivery. It represents the final portion of the passage during the second stage of labor.

A. not develop secondary sex characteristics: Secondary sex characteristics, such as muscle growth and hair distribution, are driven by testosterone produced by interstitial cells. Since LH levels are normal, these cells will still be stimulated to produce adequate testosterone. The boy would likely appear physically mature in terms of external male characteristics.

B. have impaired function of interstitial cells: Interstitial endocrine cells are specifically regulated by luteinizing hormone, which the question states is functioning normally. These cells will continue to synthesize testosterone regardless of the FSH deficiency. Their endocrine function remains intact because their primary tropic hormone is still present in the circulation.

C. be impotent (unable to have an erection): Erection is a neurovascular reflex mediated by the parasympathetic nervous system and is not directly dependent on FSH. While low testosterone can decrease libido, LH is present to maintain testosterone levels. Therefore, the physiological mechanism for erection should remain functional in this mature male.

D. be unable to produce viable sperm: Follicle-stimulating hormone is strictly required to stimulate the sustentacular cells to facilitate the final stages of sperm maturation. Without FSH, the process of spermatogenesis cannot be completed effectively, leading to infertility. The individual would produce few or no functional spermatozoa despite normal hormonal levels.