ATI RN
Endocrine System MCQ Questions Questions
Question 1 of 5
Under physiological condition most circulating Tâ‚„ is bound to
Correct Answer: C
Rationale: Thyroxine-binding globulin (TBG) binds most circulating T4 (~70%), stabilizing it in plasma for transport high affinity defines it. Prealbumin (transthyretin) binds less (~15-20%). 'Tramothynetim' is a typo, likely irrelevant. A2 globulin isn't a thyroid binder albumin binds some (~10%). TBG's dominance distinguishes it, critical for T4's bioavailability, unlike minor or erroneous binders.
Question 2 of 5
Which of the following is true regarding temperature regulation
Correct Answer: D
Rationale: Bacterial toxins (e.g., LPS) act on the organum vasculosum lamina terminalis (OVLT), releasing pyrogens (IL-1) to raise hypothalamic setpoint, causing fever immune-thermoregulation link. Sweat vaporization is ~20-30% heat loss (radiation dominates). TSH rises in chronic cold, not acutely significant. Anterior hypothalamus cools posterior triggers shivering. OVLT mediation distinguishes fever, key to infection response, unlike sweat, thyroid, or regional errors.
Question 3 of 5
the hypothalamus is essential for
Correct Answer: C
Rationale: Hypothalamus regulates renal function via ADH (water balance) and RAAS (blood pressure) essential for kidney homeostasis. Movement (basal ganglia/cerebellum) and visual acuity (occipital cortex/optic nerve) aren't hypothalamic renal control is. Its endocrine-renal link distinguishes it, critical for fluid/pressure regulation, unlike motor or sensory roles.
Question 4 of 5
What controls hormone release from the anterior pituitary gland?
Correct Answer: C
Rationale: The anterior pituitary is regulated by hypothalamic releasing hormones (e.g., TRH, GHRH) via the hypophyseal portal system, not muscle, peripheral nerves, thalamus, or CSF directly. This hypothalamic control distinguishes it as the endocrine 'master gland' coordinator, critical for thyroid, adrenal, and growth functions, contrasting with unrelated physiological triggers.
Question 5 of 5
Which of the following thyroid hormones regulates blood calcium levels?
Correct Answer: D
Rationale: Calcitriol (active vitamin D), though not a thyroid hormone, is mislisted calcitonin from thyroid C-cells lowers blood calcium, unlike T3/T4 (metabolism), TRH/TSH (thyroid stimulators). Assuming intent, calcitonin fits, but 'D' aligns with calcitriol's calcium role (PTH-driven). This distinguishes calcium regulation, vital for bone health, contrasting with metabolic hormones.