For life to continue, the body requires an adequate supply of oxygen to enter the lungs and be transferred to all cells in the body through the blood stream. In particular, if the brain, the organ that controls all bodily functions, does not have a constant supply of oxygen it will begin to fail after three or four minutes. Without oxygen, the casualty will lose consciousness, the heart beat and breathing will cease, death will result.
The ABC of life
Three elements are involve in getting oxygen to the brain. The air passage, or Air way, must be open so that oxygen can enter the body, breathing must take place so that oxygen can enter the blood stream via the lungs; and he blood must travel around the body (the Circulation, taking the oxygen to all the tissues and organs, including the brain.
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