Homeostatic mechanism is a physiologic system either open or closed that control or regulates its internal environment and tends to maintain a steady, constant condition. In this case, when it is very hot the mechanism provides cooling systems to cool the body and when it is very cold the system provides heat for the body. For instance the body temperature is sensed by the hypothalamus to be too high or low. If the temperature is above normal, it is sensed by the hypothalamus that a change should be made in order to reduce the amount of blood sent to the heating area or reverse the heating of the area. As a result, the body temperature is cooled and return to the normal temperature to be maintained.