Now, what about thermal regulation? Well, recall that our body is in a constant state of homeostasis so it does what it can to maintain homeostasis. And one of the things that it does is it needs to actually maintain a constant core temperature. So, 36.7 degrees Celsius, if our temperature increases or decreases even slightly, our proteins basically lose their efficiency and cannot function properly. So what our body does is it uses the skin to actually maintain thermal regulation via the process of sweating, perspiration as well as evaporation and radiation, as we'll see in just a moment. So every exothermic process that takes place in the body for example, let's say cellular respiration produces excessive amounts of energy, excessive amounts of heat.