A 32-year-old woman presents with a blood pressure of 155/96 mm Hg. In response to questioning, she admits that she loves licorice and eats some at least three times a week. She probably has a low level of

Correct Answer: A

Rationale: The correct answer is A: type 2 11β-hydroxysteroid dehydrogenase activity. Licorice contains glycyrrhizin, which inhibits this enzyme, leading to increased levels of cortisol and mineralocorticoids. This explains the elevated blood pressure in the patient. Choice B, ACTH, is incorrect because licorice consumption does not directly affect ACTH levels. Choice C, 11β-hydroxylase activity, is incorrect as licorice does not impact this enzyme directly. Choice D, glucocorticoid transferase, is also incorrect as licorice does not affect this enzyme's activity.

Correct Answer: D

Rationale: The correct answer is D: thyroid hormone. Thyroid hormone plays a crucial role in regulating the rate of metabolism in all body cells by influencing the production of enzymes involved in energy production. It increases the body's metabolic rate, affecting processes such as heart rate, temperature regulation, and energy expenditure. Parathyroid hormone (A) regulates calcium levels, aldosterone (B) regulates electrolyte balance, and calcitonin (C) regulates calcium metabolism, but they do not directly influence overall metabolism rate in all body cells. Thyroid hormone is the primary hormone responsible for controlling metabolism throughout the body.

Correct Answer: C

Rationale: Step-by-step rationale: 1. Bromocriptine is a dopamine agonist. 2. Dopamine inhibits prolactin release from the anterior pituitary. 3. Galactorrhea is often caused by excess prolactin. 4. By inhibiting prolactin release, bromocriptine reduces prolactin levels and eliminates galactorrhea. Summary: A: Incorrect - Bromocriptine does not antagonize prolactin action. B: Incorrect - Bromocriptine does not enhance prolactin action. D: Incorrect - Prolactin is not released from the hypothalamus.

Correct Answer: A

Rationale: The correct answer is A because oxytocin release is an example of a positive feedback control mechanism. When oxytocin is released during childbirth, it stimulates contractions, which in turn lead to more oxytocin release, creating a positive feedback loop. This helps in the progression of labor. Choice B is incorrect because oxytocin is a neurohypophyseal hormone, not an adenohypophyseal secretion. Choice C is incorrect as oxytocin's main effects are related to labor, delivery, and lactation, not menstruation. Choice D is incorrect because oxytocin primarily controls uterine contractions during labor and milk ejection during breastfeeding, not milk production itself.

Correct Answer: B

Rationale: The correct answer is B: steroid hormones, because both diffuse easily into target cells. Thyroid hormone, being a small iodinated amine, can easily pass through the cell membrane and bind to intracellular receptors, similar to steroid hormones. Unlike insulin (choice A), which binds to cell surface receptors, thyroid hormone and steroid hormones enter the cell to exert their effects. Growth hormone (choice C) and glucagon (choice D) do not share the same mechanism of entry into target cells as thyroid hormone, making them incorrect choices.