ATI RN
Multiple Choice Questions on Endocrine System Questions
Question 1 of 5
The end result of the RAAS is to
Correct Answer: D
Rationale: The renin-angiotensin-aldosterone system (RAAS) raises blood pressure: renin (kidneys) triggers angiotensin II, constricting vessels, and aldosterone, retaining sodium/water. It doesn't lower volume/pressure or raise glucose. Pressure elevation distinguishes RAAS's role, critical for hypotension response, contrasting with glucose or volume reduction effects.
Question 2 of 5
Which of the following glands is both an endocrine gland and an exocrine gland, except?
Correct Answer: D
Rationale: The pituitary gland is purely endocrine, releasing hormones (e.g., GH, TSH) into blood, lacking exocrine ducts. The pancreas is dual endocrine islets (insulin) and exocrine acini (digestive enzymes). Kidneys are endocrine (erythropoietin, renin) and exocrine (urine via nephrons). Gonads (testes/ovaries) are endocrine (testosterone/estrogen) and exocrine (sperm/eggs via ducts). Pituitary's exclusive endocrine nature distinguishes it, key to its master gland status, unlike dual-function organs.
Question 3 of 5
Which of the following comes under tumors?
Correct Answer: D
Rationale: Gigantism, acromegaly, and hyperprolactinemia often stem from pituitary adenomas (tumors), but the question implies adrenal tumors (pheochromocytoma, neuroblastoma) from context. These pituitary conditions aren't adrenal tumors, so 'none' fits if strictly adrenal-focused. This distinction clarifies tumor location, key to differential diagnosis, contrasting with pituitary-derived states.
Question 4 of 5
The endocrine gland responsible for the body's circadian rhythm is the:
Correct Answer: B
Rationale: The pineal gland secretes melatonin, peaking in darkness to regulate circadian rhythms like sleep-wake cycles, influenced by retinal light signals. The thymus matures T-cells, not rhythms. Parathyroids control calcium via PTH, not timekeeping. The pituitary, a master gland, doesn't directly manage circadian cycles hypothalamus does via pineal. Pineal's melatonin-driven role distinguishes it, key to biological timing, unlike immune, calcium, or regulatory glands.
Question 5 of 5
How do hormones from the thyroid and parathyroid regulate the calcium concentration of the blood?
Correct Answer: A
Rationale: Thyroid's calcitonin lowers blood calcium, depositing it in bones, while parathyroid hormone (PTH) raises it, mobilizing bone calcium and kidney reabsorption. Reversing this (PTH lowering, calcitonin raising) defies physiology. T3/T4 (thyroxine, triiodothyronine) regulate metabolism, not calcium. Including all thyroid hormones (T3, T4, calcitonin) with PTH overstates only calcitonin pairs with PTH. This antagonistic balance distinguishes calcium regulation, key to skeletal and blood homeostasis.