Interdependence of Body Systems Homeostasis is the process

Interdependence of Body Systems ―Homeostasis is the process by which the body maintains a stable internal environment. • Our bodies sweat to maintain a stable temperature (to keep us from overheating).

―Negative Feedback • The body changes an internal condition back to its normal state. • Used by most body systems to keep homeostasis. • Blood pressure is regulated this way.

―Maintaining Chemical Balance • Negative feedback helps maintain chemical balance. • When glucose levels are too high insluin is secreted by the pancreas. • When glucose levels are too low glucagon is secreted by the pancreas.

―Positive Feedback • Rare in a healthy body. • When change in the body occurs, the positive feedback mechanism does not restore the body to a normal state. • Example: Contractions during childbirth.

―Blood Clotting • Positive feedback • When a blood vessel is cut, it constricts and chemicals are released. • These chemicals cause blood platelets to stick to each other (clot together). • When enough platelets stick together, the hole in the blood vessel is plugged.

Questions • What is homeostasis? • Which type of feedback is used by most body systems to maintain chemical balance? • Explain what positive feedback is and give an example? • Explain what negative feedback is and give an example?