Now, at the same exact time when it's very cold outside, our skin can actually conserve heat. And how it conserves heat is it basically constricts our blood vessels found in the dermis and that redirects that shunts the blood away from the skin and that conserves energy because there is very little blood that actually radiates the energy out from our skin. So our skin cannot only dissipate that heat, but it can actually be used to store as much heat in the body as possible. Now, function number four, it also functions in excretion as well as secretion. So earlier we mentioned the existence of these sweat glands. So not only can our kidneys actually excrete waste products, ions and water, but our skin can also be used to actually excrete these molecules and ions.