Question

The temperature regulating centre is located in the:

• A. Supraoptic nucleus of hypothalamus
• B. Paraventricular nucleus of hypothalamus
• C. Preoptic nucleus of hypothalamus
• D. Suprachiasmatic nucleus of hypothalamus

Hint:

The thermostat sits in the anterior hypothalamus preoptic area, not the neuroendocrine or circadian nuclei.

Answer 1

The Correct Option is C

Step 1: Temperature homeostasis is a hypothalamic function. Among the hypothalamic nuclei, the one that senses and sets core body temperature is the preoptic nucleus of the anterior hypothalamus.

Step 2: Warm-sensitive neurons here increase their firing when blood temperature rises, switching on cooling mechanisms (sweating, vasodilation). When temperature falls, the posterior hypothalamus drives warming mechanisms (shivering, vasoconstriction).

Step 3: Eliminate the wrong options: supraoptic and paraventricular nuclei are neuroendocrine (ADH, oxytocin), and the suprachiasmatic nucleus governs the sleep-wake circadian rhythm, not thermoregulation.

\[\boxed{Preoptic\ nucleus\ of\ hypothalamus}\]