How does a human body maintain a constant temperature?

Answer 1

By the process of homeostasis.

For e.g if you have just entered a cold room

Thermoreceptors in your skin detect the change in temperature nerve impulses are generates carried by sensory neuron to the hypothalamus which is a biological thermostat.

The hypothalamus coordinates the message and send corrective measure through the motor neuron to the effectors.

The hair erector muscle contract the hairs stand straight trapping and insulating layer of air.

The shunt vessels dilates more less blood flows to the skin thus less heat is loss through radiation.

The sweat gland become inactive no sweat is produced.

The sud-cutaneous fat acts as an insulating layer reducing heat loss.

The body temperature then rises and returns to normal this is called negative feedback mechanism

The reverse occurs if the body temperature rises above normal.