Homeostasis is the process through which an organism maintains certain internal conditions, such as a human body's internal mechanisms maintaining body temperature at a specific level to prevent over or under heating; this process is important because it makes it possible for cells and organs to function properly. For example, certain parts of the human body cease to function if they become too hot or too cold; this is why it is possible for people to freeze to death or die from overheating.
Temperature regulation is an important bodily function for warm-blooded animals, because it allows them to live in any climate and to survive in places where the climate fluctuates seasonally. Homeostasis is important not only in regulating temperature but in performing tasks, such as digestion and elimination of waste. When an animal's kidneys filter its liquid intake and triggers the elimination of waste in the form of urine, that animal's body is performing a natural, involuntary function that helps regulate the amount of potentially toxic or otherwise harmful materials in the body. Homeostasis is important all the way down to the cellular level; without proper homeostasis, cells cannot perform essential tasks such as osmosis, which is a process of water passing through a cell's membrane.