Which mechanism contributes to cooling the body by evaporation of sweat?

• A. Shivering
• B. Sweating and evaporation
• C. Vasopressin release
• D. Digestion of fats

Answer: (B)

Cooling occurs when sweat produced by the skin evaporates. As liquid sweat turns into vapor, it absorbs a large amount of heat from the skin and blood, pulling heat away from the body and lowering core temperature. This evaporative cooling is driven by the hypothalamus signaling sweat glands and is most effective when the surrounding air allows evaporation (good air flow and lower humidity).

Shivering, on the other hand, generates heat through muscle activity, not cooling. Vasopressin release regulates water balance, not temperature loss through evaporation. Digestion of fats increases metabolic heat, not cooling. So the mechanism that directly cools the body by evaporation of sweat is sweating followed by evaporation.