The Body as a Whole Practice Test

Negative feedback reverses a deviation from the normal value to restore balance. When a controlled variable moves away from its set point, the body activates responses that oppose the change and push the value back toward normal. For example, if body temperature rises, mechanisms like sweating and vasodilation increase heat loss to bring it down. If temperature falls, shivering and vasoconstriction conserve heat to raise it. This opposing action maintains homeostasis by keeping the system stable. Positive feedback would amplify the change rather than correct it, feedforward involves anticipatory adjustments rather than reversing a deviation, and neutral feedback isn’t a standard mechanism for restoring balance.