Our skin is a protective layer between the body and its external environment.It works as a sensor to mo niter changes in exterior physical conditions.Different kinds of situations such as heat,cold,pain and pressure,provoke different types of nerve cells,in the skin.Thus ,the brain is sent the useful information of the happenings,outside the body,and it in turn, commands an action& nbsp; to different parts of the body.For example,when we happen to hold a flower with a thorn and detect pain,message from the arm are sent to the spine.A spine sends this message to the brain and brain command the hand muscles ...