What is Homeostasis?

Homeostasis is the maintenance of a constant internal environment within the body.

This sounds quite confusing but don’t panic – in simpler terms, homeostasis is the process which works to keep the conditions inside the body the same. This means that the reactions happening within cells can happen under their optimum conditions, which in turn means they are more efficient.

Here are some examples of conditions that need to be regulated:

Body Temperature

Blood sugar level

Water content

Homeostasis works because of negative feedback mechanisms. Negative feedback mechanisms work like this:

A change in the system from normal à this change is detected à control mechanisms are activated, returning conditions to normal à control mechanisms are switched off

Regulation of Body Temperature

Optimum body temperature is 37.5ºC. When body temperature is different from this, control mechanisms are activated to return the body to its optimum temperature.

When too hot:

Vasodilation – blood vessels dilate allow more blood to flow through the skin.

Sweating – when sweat evaporates it removes heat energy from the skin.

When too cold:

Vasoconstriction – blood vessels constrict, conserving heat in the center of the body

Shivering – shivering is caused by muscle contraction. Some of the energy produced by respiration of the muscle cells will be lost as heat, increasing body temperature.