What is the medical term meaning maintenance of a stable internal environment?

Homeostasis is the tendency of a system, especially the physiological system of higher animals, to maintain internal stability, owing to the coordinated response of its parts to any situation or stimulus tending to disturb its normal condition or function.

A steady internal environment is needed by the body to adapt to the changes outside. Had there been no homeostasis, then not only humans but other living beings would have died of drastic environment changes, which in normal cases is neutralized by the body's internal environment. For example:

• The atmospheric pressure at sea level is very high around one hundred thousand pascals. If the pressure of the blood and the other liquids in our body would not have regulated it, air would force itself inside our bodies.
• Our body produces red blood cells at high altitudes due to the lack of oxygen. This is another feature of homeostasis.

Homeostasis keeps key elements in the body such as water and temperature relatively constant, despite conditions in the environment.
The body's way of maintaining the ideal environment is called "homeostasis." Homeostasis, is the property of a system, either open of closed, that regulates its internal environment and tends to maintain a stable, constant condition. Typically used to refer to a living organism, the concept came from that of milieu interieur that was created by Claude Bernard and published in 1865. Multiple dynamic equilibrium adjustment and regulation mechanisms make homeostasis possible.