Which hormone is primarily responsible for the regulation of the menstrual cycle?

Correct Answer: C

Rationale: Estrogen is the correct answer as it plays a key role in regulating the menstrual cycle by stimulating the growth of the uterine lining. It also triggers ovulation and helps maintain the pregnancy if fertilization occurs. FSH and LH are involved in the release of eggs and development of follicles but are not primarily responsible for regulating the entire menstrual cycle. Progesterone is important for preparing the uterus for potential pregnancy but is not the primary regulator of the menstrual cycle.

Correct Answer: D

Rationale: The correct answer is D: Epididymis. The epididymis is a coiled tube located on the back of each testicle, where sperm are stored and matured after they are produced in the testes. It allows for sperm to gain motility and fertilizing capabilities. The other choices are incorrect because: A: The prostate gland secretes fluid that nourishes and protects sperm but does not store them. B: The vas deferens is a duct that carries sperm from the epididymis to the urethra but does not store them. C: Seminal vesicles produce seminal fluid that nourishes sperm but do not store them.

Correct Answer: A

Rationale: Estrogen is the correct answer because it is the primary hormone responsible for the development of the female reproductive system during puberty. Estrogen triggers the development of secondary sexual characteristics, regulates the menstrual cycle, and promotes the growth of the uterus and breasts. Testosterone is the male sex hormone and is not responsible for female reproductive system development. Progesterone's main role is in preparing the uterus for pregnancy and maintaining pregnancy, not in the initial development of the female reproductive system. FSH (Follicle-Stimulating Hormone) plays a role in regulating the menstrual cycle and stimulating the ovaries, but it is not the primary hormone responsible for the development of the female reproductive system during puberty.

Correct Answer: B

Rationale: The correct answer is B: Progesterone. Progesterone helps maintain pregnancy by inhibiting ovulation. It prepares the uterus for implantation and supports the growth of the embryo. Estrogen (A) is important for the menstrual cycle but does not specifically prevent ovulation. Testosterone (C) plays a role in male characteristics and fertility but is not directly involved in maintaining pregnancy. Human Chorionic Gonadotropin (hCG) (D) is produced during pregnancy but does not prevent ovulation; it helps in sustaining the pregnancy by supporting the corpus luteum to produce progesterone.

Correct Answer: D

Rationale: The correct answer is D: LH (Luteinizing Hormone). LH surge triggers the release of the egg during ovulation. It stimulates the follicle to rupture and release the mature egg. FSH stimulates follicle development, estrogen prepares the body for ovulation, and progesterone maintains the uterine lining post-ovulation. LH is the hormone directly responsible for the release of the egg, making it the correct choice.