Answer: Sweat glands.
Explanation: Perspiration in common terms is known as sweating which occurs through the sweat glands. This is done to regulate the temperature of the body by loss of water.
When the body is very hot due to external environment or due to some internal reactions. Then the body starts to maintain the temperature of the body by losing water molecules.This loss of water droplets on the body cools down the temperature of the body.