The appearance of some changes as the body grows older is called ageing. It ultinately leads to death.
It can be defined as deteoration in structure and function of the body cells, tissues & organs of individual.
All living being have a specific life span. Maximum life span in tortoise.
MORPHOLOGICAL AND PHYSIOLOGICAL CHANGES -
1. Decreased efficiency of heart to pump blood.
2. Reduction in the number of nephrons & taste buds.
3. Less formation of R.B.C.
4. Cells loss the capacity to retain water.
5. Skin becomes dry and wrinkeled.
6. Formation of urine is less.
7. Muscles become weak.
8. Bones become brittle.
CELLULAR CHANGES -
1. Increased number of chromosomal aberration in liver cell.
2. Greater amount of defective proteins in cell.
3. Accumulation of pigment.
4. Decreased power of multiplication in cell.
EXTRA CELLULAR CHANGES -
1. Collagen becomes less permeable, rigid & insoluble.
2. O2 & nutrients do not diffuse in cell easily.
3. Excretion is decreased.
4. Diffusion is less.