Homeostasis (A - level biology)

Definition of homeostasis, mechanisms of homeostasis (negative feedback and positive feedback), components of efficient negative feed back mechanism, homeostasis of glucose, role of pancreas in homeostasis of glucose (i.e. production of insulin) and diabetes mellitus



Homeostasis is the ability of an organism or system to maintain a stable and constant internal environment despite changes in the external environment or physiological conditions. In other words, homeostasis is the process by which the body regulates and maintains equilibrium or balance within its internal environment, including temperature, pH, fluid levels, and energy metabolism.

The mechanisms of homeostasis involve feedback loops that continuously monitor and adjust internal conditions to maintain stable levels. Negative feedback loops, for example, are used to detect and correct deviations from normal conditions, such as fluctuations in body temperature or blood glucose levels. Positive feedback loops, on the other hand, amplify changes in the internal environment and are involved in processes such as childbirth and blood clotting.

The body's major organ systems work together to maintain homeostasis. The nervous system, for example, uses sensors in the body to detect deviations from normal conditions and sends signals to coordinate responses. The endocrine system uses hormones to regulate various physiological processes, including metabolism, growth and development, and fluid and ion balance. The immune system also plays a role in maintaining homeostasis by fighting off infections and other threats to the internal environment.

Dysfunction in homeostasis can lead to diseases and health problems. For example, diabetes results from a failure in the body's ability to regulate blood sugar levels, while dehydration occurs when there is an imbalance in fluid and electrolyte levels. Understanding homeostasis and its mechanisms is thus crucial in preventing and treating various health conditions.