Like any complex machine, our bodies must maintain?

Question

Like any complex machine, our bodies must maintain relatively constant internal conditions, despite changes in the external environment. This state of equilibrium between the outside environment and the internal environment is called homeostasis. How does your body maintain homeostasis? Provide examples to illustrate this concept.

Answer 1

One best example is temperature.

Your body always maintain a body temp around 37.8 degree regardless if you are lying on the beach in a hot summer, or snowboarding on the mountains.  How do we maintain steady body temp? By using a negative feedback loop. Think of a air conditioner. There is a thermal stat, sensor, reactor. when sensor sense a change in the system, it send the signal to thermal stat, which compare the input data with its set point. If temp if higher than set point, it will have the reactor working to cool down to set point. If the temp is lower than set point, it will have the system heat up. Once the temp is cooled down or heated up, the sensor will sense the new temp, and send that to the thermal stat. Thermal stat compares the new input with its set point, if match, no more change will happen.

This is exactly the same system we use in our body. All the processes are done biologically, e.g. thermal stat will be our hypothalamus, and cooler will be sweat gland, heater will be muscle shivering, and so on.