Homeostasis, a term coined by Walter Cannon, can be defined as the ability to maintain the internal environment in an almost constant equilibrium, regardless of changes occurring in the external environment. The internal environment, in turn, is defined as the fluids that circulate through cells, the so-called interstitial fluid. To maintain homeostasis, the internal environment must keep certain values unchanged. This is achieved thanks to a number of coordinated physiological processes that ensure balance.
In plants the physiological processes responsible for this balance are:
opening and closing stomata
converting excess sugar molecules to a lesser number of starch molecules
