PSG 201 Lesson Note: Ageing in Physiology

This is time related deterioration of the physiological function necessary for survival and fertility. Maximum life span- the maximum number of years a member of a specie has been known to survive. This maximum life span depends on the special Life expectancy: the age at half the population still survive, this is not the characteristics of specie or population. 

Why do they age? 

1 The hereditary factor depending on what's going on the linage 

2 loss of cellular mass and ability of cell to divide and replicate 

3 accumulation of waste material that make cell to die 

4 changes in the structure of collective tissue No single theory adequately describe the ageing process