Answer:
Our body's internal environmental factors like; water level, solutes and body temperature keeps on changing but that happens within a very narrow range and has no adverse effect. However, when there are fluctuations in the external environment, it may have deleterious effects on an individuals' normal bodily functions. And hence, the protection of internal environment from the harms or fluctuations of external environment is termed as homeostasis. It helps regulate our body's temperature, solute and water level etc.