Homeostatic

Homeostatic refers to processes that maintain stable internal conditions in living organisms or systems. The term derives from Greek homeo- “similar” and statis “standing.”

Biological homeostasis is achieved through feedback control systems that involve sensors, a control center, and effectors. Negative feedback reduces deviations from a set point, restoring balance; positive feedback amplifies changes only transiently. Some systems also use feedforward signals that anticipate disturbances.

Common examples include thermoregulation (maintaining body temperature), osmoregulation and water balance, acid–base (pH) regulation, and glucose homeostasis controlled by insulin and glucagon. Calcium balance, blood pressure, and oxygen delivery are also tightly regulated.

Disruption of homeostatic mechanisms can cause disease or symptoms such as fever during infection, hypothermia after exposure, diabetes mellitus due to impaired glucose homeostasis, and electrolyte or fluid imbalances.

Outside biology, homeostatic principles underpin engineered control systems, such as thermostats and autonomous regulators, and are studied in fields like cybernetics and systems biology. In neuroscience, homeostatic plasticity helps stabilize neural activity.

In theory, homeostasis is the ability of a system to maintain internal stability despite external changes, and it is often distinguished from allostasis, which emphasizes adaptive adjustments to predict and cope with stress.