Final answer:
Homeostasis is the maintenance of a constant internal environment by an organism, such as the human body, despite changes in the external environment. It operates via negative feedback mechanisms that bring the body's variables like temperature or blood glucose levels back to a set point.
Step-by-step explanation:
The term you are looking for is homeostasis. This biological concept refers to the ability of an organism, such as the human body, to maintain a constant internal environment in the face of a changing external environment. It involves various physiological mechanisms, often called homeostats, which operate on the principle of negative feedback.
Negative feedback mechanisms are processes whereby a deviation from a set point triggers a response aimed at bringing the conditions back to this set point. For example, if the body's temperature rises above the set point, mechanisms like sweating and increased blood flow to the skin are activated to help cool the body down.
Similarly, if blood glucose levels increase after a meal, the body works to lower them back to a normal range. All living things, including humans, use homeostasis to keep their internal variables within normal ranges, despite external fluctuations.
This includes the regulation of body temperature, pH of bodily fluids, and the concentration of nutrients and minerals. Understanding homeostasis is crucial because it explains how organisms remain stable and functional despite the continuous changes they undergo and the varying external conditions they experience.