Which of the following best describes the role of the vagina in reproduction?

Correct Answer: B

Rationale: The correct answer is B: Passage for sperm into the uterus. Rationale: 1. The vagina serves as a pathway for sperm to travel from the male reproductive system into the female reproductive system. 2. Sperm must travel through the vagina to reach the cervix, uterus, and fallopian tubes for fertilization to occur. 3. The vagina also provides a passageway for the delivery of the baby during childbirth. Summary: A: Production of eggs - Incorrect. Eggs are produced in the ovaries, not the vagina. C: Secretion of estrogen - Incorrect. Estrogen is produced by the ovaries and plays a role in the menstrual cycle, not in the vagina. D: Site of fertilization - Incorrect. Fertilization typically occurs in the fallopian tubes, not the vagina.

Correct Answer: C

Rationale: The primary role of FSH in females is to stimulate follicle development. FSH promotes the growth and maturation of ovarian follicles, which contain the eggs. This process is essential for ovulation and the release of a mature egg for potential fertilization. Choice A, stimulating ovulation, is incorrect because FSH itself does not directly trigger ovulation. Choice B, supporting the development of the corpus luteum, is incorrect because it is primarily regulated by LH, not FSH. Choice D, preparing the uterus for pregnancy, is incorrect because FSH primarily acts on the ovaries, not the uterus.

Correct Answer: D

Rationale: The correct answer is D: All of the above. 1. FSH (Follicle-Stimulating Hormone) stimulates the production of sperms in the testes. 2. LH (Luteinizing Hormone) stimulates Leydig cells in the testes to produce testosterone, which is essential for sperm production. 3. Testosterone is crucial for the maintenance of spermatogenesis. Therefore, all three hormones (FSH, LH, Testosterone) play a significant role in the production of sperm. Choice A is incorrect because FSH alone is not solely responsible for sperm production. Choice B is incorrect because LH alone does not directly produce sperm. Choice C is incorrect because while testosterone is essential for sperm production, it is not the only hormone involved.

Correct Answer: C

Rationale: The myometrium is the muscle layer of the uterus responsible for contracting during labor to expel the fetus. This is essential for the birthing process. Choice A is incorrect because supporting the uterine lining is the role of the endometrium. Choice B is incorrect because facilitating implantation is mainly the function of the endometrium. Choice D is incorrect because estrogen secretion is primarily regulated by the ovaries, not the myometrium. Therefore, the correct answer is C as the myometrium's main function is to assist in the expulsion of the fetus during labor.

Correct Answer: B

Rationale: The correct answer is B: Progesterone. Progesterone helps prevent ovulation during pregnancy by maintaining the uterine lining and inhibiting the release of additional eggs. Estrogen supports the development of the uterine lining but does not directly prevent ovulation. hCG is produced by the placenta to support pregnancy but does not prevent ovulation. Testosterone is not involved in regulating ovulation during pregnancy.