Líkamsjafnvægi

Líkamsjafnvægi, also known as homeostasis, is the ability of an organism to maintain a stable internal environment despite external changes. This dynamic state is crucial for survival, as cells and organs function optimally within a narrow range of conditions.

Key physiological variables that are regulated include body temperature, blood glucose levels, blood pressure, and fluid balance. For example, when the body overheats, mechanisms like sweating are activated to cool down. Conversely, when the body gets cold, shivering generates heat.

Homeostatic processes are complex and involve feedback loops, primarily negative feedback. In a negative feedback system, a change in a regulated variable triggers a response that opposes the initial change, bringing the variable back to its set point. For instance, when blood glucose levels rise after a meal, the pancreas releases insulin, which helps cells absorb glucose, thus lowering blood sugar.

Disruptions to líkamsjafnvægi can lead to illness or disease. Chronic imbalances can result in conditions such as diabetes, hypertension, or hypothermia. Therefore, the body’s continuous efforts to maintain internal stability are fundamental to health and well-being.