ATI RN
Endocrine System Test Questions Questions
Question 1 of 5
Which hormone is produced by the pancreas and acts on the liver to increase blood glucose levels?
Correct Answer: A
Rationale: The correct answer is A: glucagon is produced by the pancreas and acts on the liver to increase blood glucose levels. Glucagon triggers the liver to break down glycogen into glucose, releasing it into the bloodstream. Melatonin is a hormone produced by the pineal gland and is not involved in glucose regulation. Glucagon does not act on the kidney but specifically targets the liver. Calcitonin is produced by the thyroid gland and plays a role in calcium regulation, not glucose metabolism.
Question 2 of 5
A young man presents with a blood pressure of 175/110 mm Hg. He is found to have a high circulating aldosterone but a low circulating cortisol. Glucocorticoid treatment lowers his circulating aldosterone and lowers his blood pressure to 140/85 mm Hg. He probably has an abnormal
Correct Answer: A
Rationale: The correct answer is A: 17α-hydroxylase. In this scenario, the patient presents with hypertension, high aldosterone, and low cortisol levels. This pattern suggests a defect in the enzyme 17α-hydroxylase, which is responsible for both cortisol and aldosterone synthesis. Glucocorticoid treatment lowers aldosterone levels and subsequently normalizes blood pressure. The other choices (B: 21β-hydroxylase, C: 3β-hydroxysteroid dehydrogenase, D: aldosterone synthase) are not implicated in this specific presentation and do not align with the observed hormone levels and response to glucocorticoid therapy.
Question 3 of 5
Which of the following statements regarding pituitary hormones is false?
Correct Answer: B
Rationale: Step 1: Antidiuretic hormone (ADH) is released by the posterior pituitary, and its main function is to increase water reabsorption in the kidneys, leading to decreased urine volume and increased blood volume. Step 2: If ADH causes urine volume to increase and blood volume to decrease, it would be counterproductive to its known physiological role. Step 3: Therefore, Choice B is false as it contradicts the established function of ADH. Summary: - Choice A is true because oxytocin and antidiuretic hormone are indeed produced in the hypothalamus and stored in the posterior pituitary. - Choice C is true as luteinizing hormone does trigger ovulation and stimulates the production of progesterone and some estrogens. - Choice D is true because hyposecretion of follicle-stimulating hormone or luteinizing hormone can lead to infertility in both males and females.
Question 4 of 5
The growth hormone produced by the pituitary gland is known as _______.
Correct Answer: A
Rationale: The correct answer is A: somatotropin. The growth hormone produced by the pituitary gland is known as somatotropin. - "Somato" refers to the body, indicating its role in regulating body growth. - "Tropin" refers to stimulation, emphasizing its function in promoting cell growth and regeneration. - Prolactin (B) is responsible for milk production. - Luteinizing hormone (C) and follicle-stimulating hormone (D) are involved in reproductive functions, not growth regulation.
Question 5 of 5
Which of the following hormones acts on its target tissues by a steroid hormone mechanism of action?
Correct Answer: A
Rationale: The correct answer is A: Thyroid hormone. Thyroid hormone acts on its target tissues by a steroid hormone mechanism of action because it is a lipid-soluble hormone that can diffuse through cell membranes and bind to intracellular receptors. These hormone-receptor complexes then directly regulate gene expression. In contrast, choices B, C, and D do not follow a steroid hormone mechanism of action. Parathyroid hormone (PTH) acts through G-protein coupled receptors, Antidiuretic hormone (ADH) acts through V2 receptors, and β1 adrenergic agonists act through beta-adrenergic receptors, which are all distinct from the mechanism of action of steroid hormones.