What is negative feedback?
Firstly you have a change away from optimum conditions, for instance a decrease in internal body temperature, which is detected by a receptor. The receptor relays this infromation down the communication pathway to the effector. The effector will act to reverse the change, for instance to increase internal body temperature the bodys metabolic activity will increase as there will be more excess heat energy given off. There is now a return to optimum conditions.
JB
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