Answer: Homeostasis
Explanation: Homeostasis is the ability of an organism or a cell to maintain relatively constant internal physical conditions despite changes in the external environment. This includes maintaining a stable internal environment, such as a specific range of body temperature, blood sugar levels, and pH. Homeostasis is essential for the survival and proper functioning of an organism and its cells.
It is accomplished through a complex network of physiological processes, such as feedback mechanisms, that work together to detect and respond to changes in the environment. These mechanisms help to balance the various physiological systems to maintain a stable internal environment, which is necessary for the normal functioning of cells and the organism as a whole.