What is the primary role of progesterone in pregnancy?

Correct Answer: B

Rationale: The correct answer is B: Maintain the endometrium. Progesterone plays a crucial role in pregnancy by maintaining the endometrium, which is essential for the implantation and nourishment of the fertilized egg. Progesterone helps to thicken the endometrial lining, ensuring a suitable environment for implantation and supporting the developing fetus. Promoting ovulation (A) is primarily controlled by estrogen. Stimulating labor (C) is mainly regulated by oxytocin. Supporting lactation (D) is primarily influenced by the hormone prolactin. Therefore, the primary role of progesterone in pregnancy is to maintain the endometrium for the successful development of the pregnancy.

Correct Answer: A

Rationale: The correct answer is A: Seminal vesicles. Seminal vesicles are responsible for secreting fluid that nourishes sperm. This fluid provides nutrients and energy for the sperm to survive and swim. The other choices are incorrect because: B: Prostate gland secretes a fluid that helps with sperm motility and viability, but it does not specifically nourish sperm. C: Epididymis is a coiled tube where sperm mature and are stored, but it does not secrete nourishing fluid. D: Testes produce sperm and testosterone but do not secrete nourishing fluid for sperm.

Correct Answer: A

Rationale: The correct answer is A: Secretes seminal fluid. The prostate gland in males secretes a milky fluid that makes up a significant portion of semen. This fluid helps nourish and protect sperm, aiding in their motility and viability. It also contains enzymes that aid in the liquefaction of semen after ejaculation. Summary: B: Produces sperm - Incorrect. Sperm is produced in the testes, not the prostate gland. C: Produces testosterone - Incorrect. Testosterone is primarily produced in the testes and is not a function of the prostate gland. D: Stores sperm - Incorrect. Sperm is stored in the epididymis and vas deferens, not the prostate gland.

Correct Answer: D

Rationale: The correct answer is D: hCG (human chorionic gonadotropin). hCG is produced by the placenta to maintain early pregnancy by supporting the corpus luteum, which in turn produces progesterone necessary for maintaining the uterine lining. Prolactin is responsible for milk production, not maintaining pregnancy. Estrogen plays a role in the menstrual cycle but is not the primary hormone for early pregnancy maintenance. Progesterone is crucial for pregnancy but is supported by hCG in the early stages.

Correct Answer: B

Rationale: The main function of the corpus luteum is to produce progesterone. After ovulation, the corpus luteum forms from the ruptured follicle and secretes progesterone to prepare the uterine lining for implantation. Progesterone also helps maintain the early stages of pregnancy. Estrogen is mainly produced by the follicles, not the corpus luteum. The corpus luteum does not stimulate ovulation; that is the role of the follicles. Supporting implantation is more related to the actions of progesterone rather than the corpus luteum itself.