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homeostasis ho·me·o·sta·sis (hō'mē-ō-stā'sĭs)
The ability or tendency of an organism or a cell to maintain internal equilibrium by adjusting its physiological processes.
The processes used to maintain such bodily equilibrium.
The tendency of an organism or cell to regulate its internal conditions, such as the chemical composition of its body fluids, so as to maintain health and functioning, regardless of outside conditions. The organism or cell maintains homeostasis by monitoring its internal conditions and responding appropriately when these conditions deviate from their optimal state. The maintenance of a steady body temperature in warm-blooded animals is an example of homeostasis. In human beings, the homeostatic regulation of body temperature involves such mechanisms as sweating when the internal temperature becomes excessive and shivering to produce heat, as well as the generation of heat through metabolic processes when the internal temperature falls too low.
The tendency of the body to seek and maintain a condition of balance or equilibrium within its internal environment, even when faced with external changes. A simple example of homeostasis is the body's ability to maintain an internal temperature around 98.6 degrees Fahrenheit, whatever the temperature outside.