Nokea
The Luteinizing hormone acts on the interstitial cells to produce
- A. Androgen
- B. Estrogen
- C. Progestin
- D. Testosterone
Correct Answer: D
Rationale: The correct answer is D, Testosterone. The luteinizing hormone acts on the interstitial cells in the testes to stimulate the production of testosterone. Testosterone is a male sex hormone responsible for the development of male reproductive tissues and characteristics. Androgen (choice A) is a broad term that includes testosterone, so it is not specific enough. Estrogen (choice B) and Progestin (choice C) are female sex hormones and are not produced by the interstitial cells in response to luteinizing hormone. Hence, the correct answer is D.
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Chronic cervicitis is treated with
- A. Antibiotics
- B. Antifungals
- C. Antivirals
- D. Anti-inflammatory drugs
Correct Answer: A
Rationale: Antibiotics are typically used to treat chronic cervicitis caused by bacterial infections.
Each menstrual cycle is considered as a period of ________
- A. 28 days
- B. 30 days
- C. 42 days
- D. 14 days
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.
RU486 causes abortion if it is administered before or soon after implantation. What is the specific effect of RU486?
- A. It binds to luteinizing hormone receptors, stimulating the secretion of progesterone from the corpus luteum
- B. It blocks progesterone receptors so that progesterone has no effect within the body
- C. It blocks the secretion of follicle-stimulating hormone by the pituitary
- D. It blocks the effects of oxytocin receptors in the uterine muscle
Correct Answer: B
Rationale: The correct answer is B, as RU486 blocks progesterone receptors, preventing progesterone from exerting its effects. Progesterone is crucial for maintaining the uterine lining to support a pregnancy. By blocking progesterone receptors, RU486 causes the uterine lining to break down, leading to the expulsion of the embryo and ultimately causing abortion.
Choice A is incorrect because RU486 does not bind to luteinizing hormone receptors or stimulate progesterone secretion.
Choice C is incorrect because RU486 does not block the secretion of follicle-stimulating hormone; its mechanism of action is specific to progesterone receptors.
Choice D is incorrect because RU486 does not block the effects of oxytocin receptors in the uterine muscle; its primary action is on progesterone receptors.
Which of the following statements is incorrect.
- A. a female has approximately 2-4 million oocytes at birth
- B. a female has approximately 6 million oogonia during fetal development
- C. a female ovulates about 2,000 to 4,000 oocytes during her life
- D. only approximately 1-5 oocytes are fertilized
Correct Answer: C
Rationale: The correct answer is C because a female actually ovulates only about 400-500 oocytes during her lifetime, not 2,000 to 4,000. This is due to the process of follicular atresia where many oocytes are lost before ovulation. Choice A is correct as females have a finite number of oocytes at birth. Choice B is correct as oogonia differentiate into primary oocytes during fetal development. Choice D is incorrect as typically only one oocyte is fertilized during each menstrual cycle.
A scientist studying developmental physiology performs an experiment in which a substance is given to pregnant rats that give birth to pups that have XY chromosomes but female genital organs. What was the substance given to the rats?
- A. An antibody that blocked the effect of human chorionic gonadotropin in the embryo and fetus
- B. A large quantity of estrogen-like compounds
- C. Follicle-stimulating hormone
- D. Testosterone
Correct Answer: A
Rationale: The correct answer is A: An antibody that blocked the effect of human chorionic gonadotropin in the embryo and fetus. Human chorionic gonadotropin (hCG) is crucial for male sexual differentiation. Blocking its effects would lead to the development of female genital organs in pups with XY chromosomes. Estrogen-like compounds (B) and follicle-stimulating hormone (C) are not directly involved in male sexual differentiation. Testosterone (D) is responsible for male sexual development, so giving testosterone would not result in female genital organs in XY pups.