Which statement best describes negative feedback in homeostasis?

Which statement best describes negative feedback in homeostasis?

• A. It stops or reduces the stimulus, returning the variable toward its set point
• B. It amplifies the initial stimulus
• C. It changes the set point randomly
• D. It only works for temperature

Answer: (A)

Negative feedback in homeostasis keeps conditions stable by counteracting any deviation from the normal value and pushing the system back toward its set point. When a variable is outside the desired range, sensors detect the change and a control center initiates responses that oppose that change, reducing the stimulus. A classic example is body temperature: if it gets too high, sweating and widening blood vessels help dissipate heat; if it drops, shivering and constriction of blood vessels generate or conserve heat. The goal is to stop or lessen the original stimulus, restoring balance. This is distinct from processes that amplify changes (positive feedback), which drive processes to completion rather than restore stability. It also isn’t about randomly changing the set point, and it isn’t limited to temperature—negative feedback regulates many variables such as glucose levels, pH, and water balance.

Negative feedback in homeostasis keeps conditions stable by counteracting any deviation from the normal value and pushing the system back toward its set point. When a variable is outside the desired range, sensors detect the change and a control center initiates responses that oppose that change, reducing the stimulus. A classic example is body temperature: if it gets too high, sweating and widening blood vessels help dissipate heat; if it drops, shivering and constriction of blood vessels generate or conserve heat. The goal is to stop or lessen the original stimulus, restoring balance.

This is distinct from processes that amplify changes (positive feedback), which drive processes to completion rather than restore stability. It also isn’t about randomly changing the set point, and it isn’t limited to temperature—negative feedback regulates many variables such as glucose levels, pH, and water balance.