Explain the concept of homeostasis.
Homeostasis is the control of the body’s internal conditions such as temperature, specific blood conditions or other variables within living organisms. The term ‘Homeostasis’ was first defined by the French physiologist, Claude Bernard, in the year 1865 and is the made up of two words homeo means “body” and stasis means “the same”. So in other words homeostasis is about keeping the body in balance. For example if you are too hot you may remove some of your clothing      (known as a voluntary response) and you may sweat (known as an autonomic response) to help get your body temperature back to normal.
Homeostasis is responsible for the provision of a consistent internal environment for set processes to occur. Every process, or reaction, has a desirable peak environment called the norm. Some Influences that occur, such as an external, can cause deviation away from this norm level and the body will correct this change – this is known as negative feedback.
Two good Examples of negative feedback are when blood pressure rises the heart will slow or if glucose levels are too high the pancreas secretes insulin to stimulate the absorption of glucose.
Negative feedback is the most common type of reaction, because it is only natural to rectify a potential problem, Negative feedback systems require:
  * Receptors to detect change
  * A control centre to receive the information and process the response (usually the brain).
  * Effectors to reverse the change and re­establish the original state
Negative feedback occurs when a vital variable, sometimes known as a key variable, such as the PH of the blood and tissue fluid, deviates from the accepted range or limits, and triggers response to counteract or nullify the deviation. The liver glycogen is converted into glucose in order to top up those crucial energy levels in cells. The brain and nervous system play a vital role in controlling homeostatic...