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: Body temperature is controlled by the hypothalamus, which acts like a thermostat. The key region is the preoptic area of the anterior hypothalamus, where temperature-sensitive neurons detect the temperature of the blood flowing through them.

Step 2: The preoptic nucleus integrates signals from central (blood) and peripheral (skin) thermoreceptors and triggers heat-loss responses such as sweating and cutaneous vasodilation when the body is too warm.

Step 3: The posterior hypothalamus handles heat-conservation and heat-production responses such as shivering and vasoconstriction. Together these centres keep core temperature near the set point.

Step 4: The distractors serve other roles: the supraoptic and paraventricular nuclei produce ADH and oxytocin, and the suprachiasmatic nucleus is the master circadian clock. Hence the correct answer is the preoptic nucleus.