Which hormone stimulates the secondary female sex organs?

Correct Answer: D

Rationale: The correct answer is D: estrogen. Estrogen is the hormone that stimulates the growth and development of secondary female sex organs like the breasts, uterus, and fallopian tubes. It plays a crucial role in regulating the menstrual cycle and preparing the body for pregnancy. FSH and LH are hormones released by the pituitary gland that primarily regulate the ovarian cycle, while GnRH is a hormone released by the hypothalamus to stimulate the pituitary gland to release FSH and LH. Estrogen, being a primary female sex hormone, directly influences the development and function of secondary sex organs in females.

Correct Answer: C

Rationale: The correct answer is C: Testosterone. Testosterone is the primary male sex hormone produced by the testes. It plays a crucial role in the development of male reproductive tissues and secondary sexual characteristics. Progesterone (A) is a female sex hormone produced in the ovaries, not the testes. Vasopressin (B) is a hormone produced by the pituitary gland, not the testes. "None of the above" (D) is incorrect as testosterone is indeed released from the testes.

Correct Answer: A

Rationale: The correct answer is A: Sperm maturation. The epididymis is a coiled tube where sperm undergo maturation, gaining motility and ability to fertilize an egg. It does not produce sperm (incorrect B), but stores sperm for a short period (incorrect C) before ejaculation. It also does not provide nutrition to sperm (incorrect D).

Correct Answer: A

Rationale: The correct answer is A: Progesterone. After ovulation, the corpus luteum forms from the ruptured follicle and secretes progesterone to prepare the uterus for implantation. Progesterone helps maintain the endometrial lining for potential pregnancy. Choice B, Relaxin, is secreted by the corpus luteum, but its main function is to soften the cervix and pubic symphysis. Choices C and D, LH and FSH respectively, are pituitary hormones involved in the menstrual cycle regulation, not directly secreted by the corpus luteum.

Correct Answer: C

Rationale: The correct answer is C: a diploid fertilized ovum. A zygote is formed when a sperm fertilizes an ovum, resulting in a diploid cell with a complete set of chromosomes. This marks the beginning of a new individual. A) Incorrect: An ovum is a haploid cell produced by the female reproductive system. B) Incorrect: A secondary oocyte is a haploid cell that has undergone meiosis II but has not been fertilized yet. D) Incorrect: A polar body is a haploid cell that is produced during oogenesis and eventually disintegrates.