Homeostasis is one of the seven features common to all life forms. Every organism needs the ability to regulate their internal environment in response to their activity and their external environment. It is crucial to the organism’s health to be able to maintain a constant internal environment. For example, the ideal body temperature for humans is 98.6 degrees Fahrenheit . When this temperature rises just a few degrees it can cause a serious effect such as heatstroke or fever. Because of homeostasis, however, our body has many mechanisms to maintain our ideal body temperature. When we get too hot, for example, we sweat and the blood vessels in our skin dilate. The sweat evaporates and cools our skin while the dilated blood vessels allow heat to escape. On the other hand, when our body temperature is lower than normal we shiver and the blood vessels in our skin constrict. The shivering of our skeletal muscles generates heat while the constriction of our blood vessels minimizes the amount of heat we lose.
Homeostasis runs by using negative feedback. When the body temperature becomes too hot, our body activates cooling mechanisms (such as sweating). When we get too cold, the opposite is true.
Whereas human sweat to cool themselves down, dogs have a different mechanism. Dogs start panting, or breathing heavily with their tongue hanging out. As they breathe in the cool air, an almost fan-like process occurs that cools down the blood in their nose. Because the major blood vessels in their head run very close to the blood vessels in their nose, the cooler blood is then circulated throughout the rest of the body. They breathe out warm air to further cool down their body temperature.