Which hormone promotes a small number of primary follicles within the ovary to grow and mature each month?

Correct Answer: D

Rationale: The correct answer is D, follicle-stimulating hormone (FSH). FSH promotes the growth and maturation of primary follicles in the ovary each month. It stimulates the follicles to develop and produce estrogen. LH surge triggers ovulation. A and B are involved in the menstrual cycle, but they do not specifically promote the growth of primary follicles. C is not a hormone involved in the process.

Correct Answer: C

Rationale: The secretory phase follows ovulation in the menstrual cycle. During this phase, the corpus luteum, formed from the ruptured follicle, secretes progesterone, maintaining the endometrium for potential implantation of a fertilized egg. Choice A is incorrect as ovulation occurs in the preceding phase (ovulatory phase). Choice B is incorrect as the functional layer of the endometrium thickens during the secretory phase to support a potential pregnancy. Choice D is incorrect as the functional layer of the endometrium is not shed during the secretory phase, but rather maintained for pregnancy support.

Correct Answer: B

Rationale: The correct answer is B: spermatogonia. Spermatogonia are the cells within the seminiferous tubules of the testes that give rise to sperm cells. Testosterone is produced by Leydig cells, not spermatogonia. A is incorrect because the spermatic cord does not produce testosterone. C is incorrect as the testis is the overall organ where the seminiferous tubules are located. D is incorrect as oogonia are female germ cells found in the ovaries, not the testes.

Correct Answer: A

Rationale: The correct answer is A: sperm. Sperm is not a component of semen; it is the male reproductive cell. Semen is composed of fluids from the epididymis, seminal glands, and prostate, which provide nourishment, protection, and transportation for sperm. The epididymis stores and matures sperm, seminal glands produce seminal fluid, and the prostate contributes prostatic fluid. Sperm is only a part of semen and not a component of it. Therefore, choice A is the correct answer.

Correct Answer: C

Rationale: The correct answer is C: blastocyst. At this stage of development, the embryo is a hollow ball of cells with an inner cell mass. This structure is called a blastocyst. A is incorrect because testosterone is a hormone, not a cell structure. B is incorrect as it does not describe the early stage of embryonic development. D is incorrect as luteinizing hormone is a hormone involved in the menstrual cycle, not embryonic development.