ATI RN
Multiple Choice Questions Endocrine System Questions
Question 1 of 5
Melatonin is secreted by which gland?
Correct Answer: A
Rationale: The correct answer is A: Pineal gland. Melatonin is a hormone that regulates sleep-wake cycles and is primarily secreted by the pineal gland located in the brain. The pineal gland responds to darkness by releasing melatonin, which helps to induce sleep. The other choices, B: Thyroid, C: Thymus, and D: Adrenal, do not secrete melatonin. The thyroid gland produces hormones that regulate metabolism, the thymus gland is involved in immune function, and the adrenal glands secrete hormones like cortisol and adrenaline. Therefore, the pineal gland is the correct answer for melatonin secretion.
Question 2 of 5
Which of the following statements is true?
Correct Answer: A
Rationale: Rationale for Choice A: 1. The hypothalamus produces oxytocin and antidiuretic hormone (ADH). 2. These hormones are transported via the hypothalamic-pituitary portal system to the posterior pituitary for storage. 3. When needed, the posterior pituitary releases these hormones into the bloodstream. 4. Oxytocin is involved in labor and milk ejection, while ADH regulates water balance by increasing water reabsorption in the kidneys. Summary of other Choices: B. Incorrect - ADH, when released, causes urine volume to decrease and blood volume to increase by increasing water reabsorption. C. Incorrect - Luteinizing hormone triggers ovulation and stimulates progesterone production but is released by the anterior pituitary, not the hypothalamus. D. Incorrect - Hyposecretion of FSH or LH can lead to infertility, not necessarily sterility, and the effects differ between males and females.
Question 3 of 5
Which hormone is involved in the regulation of calcium levels in the blood?
Correct Answer: A
Rationale: The correct answer is A: parathyroid hormone. Parathyroid hormone is responsible for regulating calcium levels in the blood by increasing calcium release from bones, enhancing calcium absorption in the intestines, and promoting calcium reabsorption in the kidneys. This hormone acts to elevate blood calcium levels when they are low. B: Aldosterone is a hormone that regulates sodium and potassium levels, not calcium. C: Calcitonin is involved in lowering blood calcium levels by inhibiting the breakdown of bone tissue, but it is not the primary hormone responsible for regulating calcium levels in the blood. D: Thyroid hormone plays a role in metabolism regulation, growth, and development, but it is not directly involved in the regulation of calcium levels in the blood.
Question 4 of 5
A patient presents with tiredness, weakness, anorexia, apathy, abdominal pain, hyperpigmentation and postural hypertension. Upon infection he appears to be in cardiogenic shock and his blood volume is depleted. His sodium levels are low, potassium levels are high. Which of the following would also be elevated?
Correct Answer: D
Rationale: The correct answer is D: ACTH. In this scenario, the patient is exhibiting symptoms of adrenal insufficiency, specifically Addison's disease. ACTH levels would be elevated due to the lack of negative feedback from cortisol, which is typically low in adrenal insufficiency. TSH (A) and T4 (B) would be normal or low due to the hypofunction of the adrenal gland, not the thyroid. Adrenal hormones (C) would be low in adrenal insufficiency, not elevated.
Question 5 of 5
In its action in cells, aldosterone
Correct Answer: A
Rationale: The correct answer is A because aldosterone increases the transport of epithelial sodium channels (ENaCs) from the cytoplasm to the cell membrane. This process leads to enhanced sodium reabsorption in the kidneys, promoting water retention and increasing blood pressure. Choices B and C are incorrect as aldosterone does act on the cell membrane and binds to a receptor located in the cytoplasm, which then translocates to the nucleus. Choice D is incorrect as aldosterone does not directly activate heat shock proteins.