What factor will inhibit LH secretion?

Correct Answer: B

Rationale: The correct answer is B: progesterone. Progesterone inhibits LH secretion by exerting negative feedback on the hypothalamus and pituitary gland. This hormone signals that the body has enough progesterone and does not need additional LH for ovulation. FSH (choice A) stimulates LH secretion, estrogen (choice C) typically increases LH secretion during the menstrual cycle, and LH (choice D) does not inhibit its own secretion.

Correct Answer: B

Rationale: The correct answer is B: Seminiferous tubules. These tubules are located within the testes and are the specific structures where sperm production occurs through a process called spermatogenesis. Sperm cells are produced within the seminiferous tubules and then mature as they move through the epididymis (choice D) and vas deferens (choice A). The albuginea (choice C) is the tough outer covering of the testes and does not play a direct role in sperm production. Therefore, the seminiferous tubules are the primary site for sperm production in the male reproductive system.

Correct Answer: C

Rationale: The correct answer is C, Uterine tubes. Fertilization occurs in the uterine tubes, also known as Fallopian tubes, where the sperm and egg meet to form a zygote. The uterine tubes provide a suitable environment for fertilization to take place. A: Ureters - Incorrect, ureters are tubes that carry urine from the kidneys to the bladder, not involved in fertilization. B: Urethra - Incorrect, the urethra is a tube that carries urine from the bladder out of the body, not involved in fertilization. D: Ovaries - Incorrect, ovaries release eggs but fertilization does not occur in the ovaries; rather, it occurs in the uterine tubes.

Correct Answer: C

Rationale: The correct answer is C: aldosterone. The cell labeled H is located in the adrenal gland zona glomerulosa, which secretes aldosterone. Aldosterone regulates electrolyte balance by increasing reabsorption of sodium and water in the kidneys. Renin (A) is secreted by the juxtaglomerular cells, progesterone (B) is produced by the ovaries and adrenal glands, and estrogen (D) is produced by the ovaries and placenta. None of these hormones are secreted by the cell labeled H.

Correct Answer: A

Rationale: The correct answer is A: 28 days because the average menstrual cycle length is typically around 28 days, although it can vary. The menstrual cycle consists of different phases such as menstruation, follicular phase, ovulation, and luteal phase, which collectively last around 28 days on average. Choice B (30 days), C (42 days), and D (14 days) are incorrect because they do not represent the typical duration of a menstrual cycle. It's important to note that individual variations in cycle length are common, but 28 days is considered a standard reference point.