When you touch boiling water, for example,get a cut, or even exercise too much, a special receptor on the neuron is activated, sending a signal to the brain - that hurts!.

VOA: standard.2010.05.04

It works by a control mechanism called negative feedback, and the thermostat is measuring the temperature and then sending a signal to a heater somewhere.

是通过一种叫做负反馈的控制机制,探测器测量温度,再把信号传给加热器

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