What is the function of the uterine lining during pregnancy?

Correct Answer: A

Rationale: The correct answer is A: Nourish the embryo. During pregnancy, the uterine lining, also known as the endometrium, thickens to provide a rich blood supply and nutrients to support the developing embryo. This lining helps in implantation and facilitates the exchange of oxygen, nutrients, and waste products between the mother and the embryo. Choice B is incorrect as uterine contractions are primarily controlled by the muscles of the uterus. Choice C is incorrect because the uterine lining does not directly support the fetus during delivery; rather, it is the uterine muscles that aid in labor. Choice D is incorrect as the placenta, not the uterine lining, is responsible for providing nutrients to the fetus.

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: B

Rationale: The correct answer is B: Leydig cells secrete testosterone. These specialized cells are located in the testes and are responsible for producing and releasing testosterone, the primary male sex hormone. Testosterone plays a crucial role in the development of male reproductive organs, sperm production, sex drive, and secondary sexual characteristics. Choice A is incorrect because sperm production is primarily carried out by the Sertoli cells. Choice C is incorrect as Leydig cells do not store sperm. Choice D is incorrect as sperm transport is mainly facilitated by the vas deferens and other structures in the male reproductive system.

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.