7.16—Negative and positive feedback

A homeostatic control system detects deviation from a set point and coordinates effectors. Negative feedback opposes the deviation and returns the variable toward its normal range; positive feedback reinforces a change until a defined endpoint.

Thermoregulation increases heat loss when body temperature rises, whereas clotting can amplify activation until a wound is sealed.

Homeostasis is dynamic equilibrium, not a perfectly fixed value. Do not label every response negative or assume positive feedback is automatically unstable.