A drug is given that affects the initial phases of spermatogenesis to aid in a patient’s infertility complaints. How much time would it take for the effects of this drug to be seen?

Correct Answer: D

Rationale: The correct answer is D (86 days) because spermatogenesis is a process that takes around 74 days from the initial division of spermatogonia to the release of mature spermatozoa. The drug affecting the initial phases of spermatogenesis would take at least one full cycle of spermatogenesis to show its effects, which is around 74 days. Therefore, it would take approximately 86 days for the effects of the drug to be seen. Choice A (4.6 days) is too short for spermatogenesis to complete, so the effects of the drug would not be observable in this time frame. Choice B (16 days) and Choice C (22 days) are also insufficient for a full cycle of spermatogenesis to occur, hence the effects of the drug would not be evident within these durations.

Correct Answer: A

Rationale: The correct answer is A: oxytocin. Oxytocin is the hormone responsible for stimulating uterine contractions during labor and childbirth. It is produced by the pituitary gland and plays a crucial role in the initiation and progression of labor. Estrogen (B) and progesterone (D) are involved in the menstrual cycle and pregnancy maintenance but do not directly stimulate uterine contractions. Granular cell carcinoma (C) is a type of cancer and not a hormone related to uterine contractions.

Correct Answer: B

Rationale: The correct answer is B because in nephrogenic diabetes insipidus, the kidney tubules are unable to respond to antidiuretic hormone (ADH). This results in the inability to concentrate urine, leading to excessive dilute urine output. Lines A and D in the figure represent a high urine output (polyuria) and low urine osmolality, which are characteristic of nephrogenic diabetes insipidus. Choice A (A and C) is incorrect because line C does not show low urine osmolality. Choice C (B and C) is incorrect because line B does not show high urine output. Choice D (B and D) is incorrect because line D does not show low urine osmolality.

Correct Answer: A

Rationale: Step 1: Newborn infants have limited hepatic capacity to store and synthesize glycogen and glucose. Step 2: This limited capacity results in the plasma glucose concentration not being maintained in a normal range for more than a few hours after feeding. Step 3: Feeding every few hours ensures a constant supply of glucose to maintain plasma glucose levels. Step 4: Thus, it is important to feed newborn infants every few hours to prevent hypoglycemia. Summary: A: Correct - Maintaining plasma glucose levels due to limited hepatic capacity. B: Incorrect - Protein concentration is not the primary concern for feeding frequency. C: Incorrect - Keeping food in the stomach constantly does not improve gastrointestinal function. D: Incorrect - Hypoproteinemic edema is not the primary reason for feeding frequency.

Correct Answer: D

Rationale: The correct answer is D: Abnormally high levels of testosterone in the maternal blood. This can cause virilization of the female fetus, leading to the development of male external genitalia. Testosterone exposure during fetal development can result in the formation of a penis and scrotum without testes in a genetic female (XX). Rationale: 1. Testosterone is responsible for the development of male external genitalia. 2. XX chromosomes indicate a genetic female. 3. Lack of testes indicates incomplete masculinization. 4. High levels of testosterone can override the default female development pattern. Other choices are incorrect because: A: Human chorionic gonadotropin does not directly affect fetal genital development. B: Estrogen is not responsible for male genital development. C: Luteinizing hormone does not directly influence the development of external genitalia in the fetus.