Which structure produces testosterone in males?

Correct Answer: D

Rationale: The correct answer is D: Leydig cells. Leydig cells are located in the testes and are responsible for producing testosterone in males. Testosterone is a key hormone for male development and reproductive function. The other choices (A: Epididymis, B: Seminiferous tubules, C: Prostate gland) are not involved in testosterone production. The epididymis stores and transports sperm, seminiferous tubules produce sperm, and the prostate gland secretes fluids that nourish and protect sperm. Therefore, Leydig cells are the correct choice for testosterone production in males.

Correct Answer: B

Rationale: The correct answer is B: Ovaries. The ovaries are the primary site of estrogen production in females. Estrogens are steroid hormones produced mainly by the developing ovarian follicles. The adrenal gland (A) primarily produces hormones like cortisol and aldosterone, not estrogen. The pituitary gland (C) releases hormones that regulate the ovaries but does not produce estrogen directly. The uterus (D) is the site where the fertilized egg implants and grows during pregnancy, but it does not produce estrogen.

Correct Answer: C

Rationale: The corpus luteum is a temporary endocrine structure formed in the ovary after ovulation. It functions to produce both estrogen and progesterone. Estrogen helps in the growth and development of the endometrial lining, while progesterone maintains the uterine lining for potential implantation of a fertilized egg. The other choices are incorrect because the corpus luteum does not solely produce estrogen (choice A) or progesterone (choice B). Additionally, it does not produce hCG (choice D), which is mainly produced by the placenta during pregnancy.

Correct Answer: A

Rationale: Testosterone is the correct answer because it is the primary male sex hormone responsible for the development of male secondary sexual characteristics such as facial hair, deep voice, and muscle growth. Testosterone is produced by the testes in males. Progesterone (B) is a female sex hormone involved in the menstrual cycle and pregnancy. Estrogen (C) is the primary female sex hormone responsible for the development of female secondary sexual characteristics. FSH (D) is a hormone that stimulates the production of sperm in males and the maturation of eggs in females, but it is not directly responsible for male secondary sexual characteristics.

Correct Answer: D

Rationale: The correct answer is D: hCG. Human Chorionic Gonadotropin (hCG) is produced by the placenta after implantation, confirming pregnancy. Estrogen (A) and Progesterone (C) are important hormones in pregnancy but do not specifically confirm it. FSH (B) is Follicle-Stimulating Hormone, which is not directly related to pregnancy confirmation. hCG is the most reliable indicator of pregnancy as its levels rise significantly in early pregnancy, making it the correct choice.