ABSTRACT
In general the human body consists of vital organs-heart, brain, kidneys and liver-and non-vital organs-eyes, ears, joints, etc. As with all bodily tissues there is a constant process of cellular turnover, but in the ultimate failure of the processes of repair and regeneration (ageing) there is in a sense a race between which systems fail first. If a vital organ fails, by definition the person dies. If the vital organs continue to function, the non-vital organs inevitably decay.
