What is the main difference between positive feedback and negative feedback in biological systems?

In biological systems, the main function of negative feedback is to maintain homeostasis and stabilize the internal environment. Negative feedback mechanisms detect deviations from a set point and activate processes that counteract those changes, effectively working to return the system to equilibrium. For example, in thermoregulation, if the body temperature rises above the normal range, mechanisms such as sweating and increased blood flow to the skin are activated to cool down the body, thereby stabilizing the temperature around a set point.

The other options incorporate misunderstandings about the roles of positive and negative feedback. Positive feedback does not maintain stability; rather, it amplifies changes and drives processes to completion, such as in childbirth where the release of oxytocin increases contractions. Therefore, the distinction lies in the fact that negative feedback seeks to stabilize the system by reducing deviations, while positive feedback enhances deviations away from the norm.