"maintaining a steady state internal environment, despite a changing external environment, is called homeostasis"
Homeostasis is any self-regulating process by which biological systems tend to maintain internal stability with the tendency to resist external changes. Homeostasis involves negative and positive feedback loops. Homeostasis depends on the ability of the body to detect (via sensors) and oppose these changes. From sensors signals are sent to the control center in the brain, and then after processing the information the effectors are activated.