Age means the part or duration of a being which is between its beginning and any given time. It is countable and one of the stages of life at which some particular changes or development occurs, which distinguishes itself from any other stage of life.
In growth-related studies, age plays an important role since it is considered for all physiological, psychological and cognitive growth of an individual.
Age is also a universal phenomenon and the changes that an individual undergoes, with the increase in age are also universal with slight changes in the onset of the changes. The development and maturation of an individual could be studied on a dynamic basis with the help of age. With the growth in age, various changes are seen in various body systems.
Age is an important factor as the various changes in growth are resulted from changes in body systems which could be studied with respect to age. These changes are studied keeping in mind the changes with time.
Changes in Body With Time
1. The Skin
With growing age, the skin flattens due to the loss of many tissues such as subcutaneous fat, skin cells, sebaceous glands, sweat glands, melanocytes and hair follicles. With age, lentigo occurs, the blood flow to the skin also decreases and nerve endings are lost or become less sensitive that results in less effectiveness for protection against bacteria or an insulator as a thermal regulator and as sensory receptor.
These results in wrinkling, loss of elasticity, and freedom of movement and expression are inhibited. The slowing of circulation results in slower healing. The loss of colour is also seen, as the hair becomes grey.
2. The Skeletal System
The loss of bone matter is the primary change in the ageing of the skeletal system. The basic cause of bone loss is the relative rates of production of osteoblasts and osteoclasts changes so that more bone matter is dissolved than is laid down. This loss is much greater in women than in men.
- Osteoblasts– Bone forming cells
- Osteoclasts– Bone dissolving cells
Other factors seen in the skeletal system with growing age are loosened cartilage around the joints, depleted lubricating fluid in the joints, and hardened and contracted ligaments. These factors occur more in men than in women.
There are significant effects of these changes on our health status because as the bones become brittle they become less supportive of our activities, resulting in less activity, which in turn results in poorer health. The excess bone that has been taken up tends to reside in the arteries and local blood vessels, causing decreased circulation.
3. The Muscular System
Muscle cells are post-mitotic cells that are that cannot replace themselves once they are formed and so all muscle cell loss is permanent. Muscular response gradually slow down with age even under the best conditions, although the loss of muscular capabilities is mostly due to result of cell loss due to inactivity of the body.
With the loss in muscle cells, weakness and slowness of the muscles also increase. Exceptions are also seen in the muscles of the left ventricle of heart, and the diaphragm as they do not lose muscle fibres with age since they are continually active.
4. The Neurosensory System
The nerve cells (neurons) are also post-mitotic fixed cells and with growing age, they lose dendrites, dendritic spines, and end branches; all of which are the intermediary parts necessary for the communication with one another.
As the nervous system ages, signal conduction becomes slower but much more so at the nerve synapses (nerve junctions) than within the nerve cells themselves. There is loss of taste buds, olfactory cells (sense of smell), nerve endings in the skin, and even brain cells.
The hearing sensitivity degrades, especially in the higher ranges, as the ear ossicles harden. The vision changes as the lens of the eye becomes less flexible and yellows, and this results in the requirement of more light and glasses for close work.
5. The Gastrointestinal Tract
The mouth, esophagus, stomach, small intestine, gallbladder, liver, pancreas, and large intestine all come together to form the Gastrointestinal tract. In the mouth, taste buds and teeth are lost after adulthood. Problems with the esophagus with growing can be dysphagia (difficulty swallowing), substernal pain, heartburn, belching, and general epigastric discomfort which is also seen after adulthood.
Atrophic changes in the stomach, especially hypoacidity and achlorhydria, are common with growing age. Cell replacement is active in the small intestine, so few changes occur with ageing but obstructions are not uncommon.
Gall bladder problems are most marked after age 65, rather than in middle age. Problems with the pancreas usually begin to develop about age 40 and they do tend to increase with age.