|MadSci Network: Biochemistry|
Reactions that absorb energy from the environment are called endothermic reactions. One common example is the evaporation of water. It requires energy to convert liquid water into gaseous water. That energy often comes from heat. Therefore, the evaporation of water has a cooling effect. One common location on the body where an endothermic reaction takes place, as you can probably now guess, is on our skin when we sweat. The water in the sweat evaporates, taking heat from our skin, and cooling down our bodies.
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