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Our bodies need to control things like body temperature and water level to keep them from changing. The process of keeping things the same is called homeostasis.

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Homeostasis is how the body keeps conditions inside it the same. Scientists describe it as the maintenance of a constant internal environment.

  • body temperature at 37°C
  • the amount of water inside our body
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How we keep things the same

  • First, we need receptors to detect when things such as temperature change.

  • Then we need a processing centre to receive this information and coordinate our response.

  • Finally, we need effectors to produce a response that ensures our body temperature stays at 37°C.

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Negative feedback

Negative feedback ensures that, in any control system, changes are reversed and returned back to the set level.

negative feedback keeps our body temperature at a constant 37°C. If we get too hot, blood vessels in our skin vasodilate (become larger) 

If we get too cold blood vessels in our skinvasoconstrict (become smaller)

The other factors also controlled in the body by negative feedback are:

  • blood oxygen levels
  • salt levels
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lol did you take this of bbc's gcse bitesize?

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