AP BIOLOGY

Detailed explanation-1: -The cooling effect of perspiration evaporation makes use of the very large heat of vaporization of water. This heat of vaporization is 540 calories/gm at the boiling point, but is even larger, 580 cal/gm, at the normal skin temperature.

Detailed explanation-2: -That’s because cooling your body via sweating relies on a principle of physics called “heat of vaporization.” It takes energy to evaporate sweat off of your skin, and that energy is heat. As your excess body heat is used to convert beads of sweat into vapor, you start to cool down.

Detailed explanation-3: -Humans use perspiration from the skin as one means of thermoregulation, because it has a cooling effect due to the latent heat of evaporation of water. Animals with few sweat glands, like dogs, pant to achieve evaporative cooling through the tongue and mouth. Few other animals depend on sweating to cool down.

Detailed explanation-4: -Its main function is to control body temperature. As the water in the sweat evaporates, the surface of the skin cools.