What is meant by the term 'homeostasis' in biological systems?

The term 'homeostasis' refers to the ability of a biological system to maintain a stable and constant internal environment despite changes in external conditions. This concept is crucial for the survival of organisms, as it ensures that physiological processes can operate optimally.

In the context of living organisms, homeostasis encompasses a variety of physical and chemical conditions, including temperature, pH, hydration, and electrolyte balance, among others. The body continuously makes adjustments to keep these factors within a narrow range, which is vital for processes like enzyme activity, cellular metabolism, and overall health.

The other options do not accurately capture the essence of homeostasis. While gradual changes in population might relate to ecological dynamics, they do not pertain to the stability of an individual's internal environment. Increased energy levels are more associated with metabolic rates rather than the concept of stability. Lastly, temporary equilibrium suggests a fleeting or unstable state, which contrasts with the enduring stability that homeostasis embodies.