What is the role of the interstitial cells in the testes?

Correct Answer: A

Rationale: The correct answer is A: Synthesize testosterone. Interstitial cells in the testes, also known as Leydig cells, are responsible for producing testosterone, the primary male sex hormone. Testosterone plays a crucial role in the development of male reproductive organs, secondary sexual characteristics, and overall reproductive function. The other choices are incorrect because storing sperm (B) is the role of the epididymis, producing seminal fluid (C) is the role of the seminal vesicles, and maturing sperm (D) occurs in the seminiferous tubules through the process of spermatogenesis.

Correct Answer: A

Rationale: Estrogen is the correct answer because it increases the permeability of the cervix to sperm during ovulation. Estrogen is responsible for the changes in cervical mucus consistency, making it easier for sperm to swim through to reach the egg. Progesterone, FSH, and LH do not directly affect cervical mucus permeability during ovulation. Progesterone prepares the uterine lining for implantation, FSH stimulates follicle growth, and LH triggers ovulation.

Correct Answer: A

Rationale: Step 1: Oxytocin is known as the "love hormone" and plays a crucial role in uterine contractions. Step 2: During labor, oxytocin is released to stimulate rhythmic contractions of the uterus. Step 3: These contractions help to push the baby through the birth canal. Step 4: Therefore, the primary purpose of oxytocin during labor is to stimulate uterine contractions for the progression of labor. Summary: Choice A is correct because oxytocin's main function during labor is to stimulate uterine contractions. Choices B, C, and D are incorrect as oxytocin does not inhibit contractions, increase progesterone production, or directly prepare the cervix for dilation during labor.

Correct Answer: A

Rationale: The correct answer is A: Testosterone. Testosterone is the primary male sex hormone responsible for the development of secondary sexual characteristics such as facial hair, deepening of the voice, and muscle growth. It is produced by the testes in males. Estrogen (B) and Progesterone (C) are female sex hormones, while LH (D) is luteinizing hormone that stimulates the production of testosterone in males but is not responsible for the development of secondary sexual characteristics.

Correct Answer: C

Rationale: The correct answer is C because the fallopian tubes transport the ovum from the ovary to the uterus for fertilization. This is their primary function in the reproductive system. Choice A is incorrect because the ovaries produce eggs, not the fallopian tubes. Choice B is incorrect as the fallopian tubes do not transport sperm but rather the egg. Choice D is also incorrect because estrogen is produced by the ovaries and other tissues, not by the fallopian tubes. In summary, the fallopian tubes serve as a pathway for the ovum to travel from the ovary to the uterus for potential fertilization.