Biological theories of aging
Aging is a biological phenomenon all the living things are undergoing. We are not sure about anything in the world except the aging. We are approaching getting nearer to the death from the time of the birth onwards. No living thing in the world has the ability to defeat death as it occurs sometimes naturally and sometimes accidently. Aging has different dimensions like physical, psychological, and social. There are many biological theories with respect to aging.
Simple Deterioration, Non-programmed Aging and Programmed Aging, Autoimmunity theory, Free radial theory, Telomerase Theory of Aging etc are some of them. This paper briefly explains some of the biological theories of aging mentioned above.
Aging: simple deterioration theory/wear and tear theory
Simple Deterioration Theory argues that Aging is the accumulative result of universal deteriorative processes such as oxidation, molecular damage, wear and tear, or accumulation of adverse byproducts (Goldsmith, p. 3). Even though man and machine are two entirely different things, both of them have certain similarities in their functioning.No machine is able to function more than particular period of time because of the wear and tear due to continuous work. Same way bodies of the living things are also undergoing continuous work which causes damages to the parts of the body.
Even though we refill the fuels in the form of food, nutrients and water, there are certain limitations for the body of the living things to survive for a longer period. In chemistry, most of the chemical reactions yield products and by-products. These by-products are not necessarily the intended one. Same way our body chemistry also yields different by-products which are harmful to our health and may reduce our life p. At the same time we cannot avoid the production of such by-products
Aging: non-programmed aging theory
Non-programmed theory of aging believes that aging is a passive result of an organism’s inability to better resist fundamental deteriorative processes. Moreover aging serves no purpose, is not an adaptation, and is not programmed (Goldsmith, p. 8).
Our body is undergoing lot of changes and processes virtually in very seconds. Most of the activities inside our body are beyond our control.For example, the pumping of blood by the heart is not done with our permission. We cannot stop any of the internal functions. Everything inside our body is tuned to do certain things and any malfunctions occur inside our body may result in diseases. We are passive observers of our body functions.
Aging: programmed aging theory
“Organisms are purposely designed and genetically programmed to age or otherwise limit life p because the deterioration and life p limitation serves an evolutionary purpose” (Goldsmith, p. 9). It is unimaginable to think of a world without death for living things. The earth might not be able to give shelter to all the living things if death was not there. So as part of the natural evolution process, nature has programmed death; natural and accidental to all the living things. August Weismann (1834–1914), the great German theorist and experimental biologist of the 19th century, was one of the first biologists to use evolutionary arguments to explain aging. His initial idea was that there exists a specific death-mechanism designed by natural selection to eliminate the old, and therefore worn-out, members of a population. The purpose of this programmed death of the old is to clean up the living space and to free up resources for younger generations (Gavrilov &Gavrilova).
Aging: autoimmunity theory
This theory argues that our body has the tendency to reject its own tissues with the increasing age (Biological theories of aging, p. 21). For example, it is difficult for the older people to take heavy foods because of digestion problems. Moreover, it is a fact that we are losing many hairs and skin and nail cells periodically. In other words, our body has the tendency to reject certain things as time passes.
Free radical theory
Free radical theory says that certain chemical compounds in our body does damage which accumulates to produce aging (Biological theories of aging, p. 22). Our body is just like a factory.
We know that a factory can produce lot of industrial wastes and these wastes can sometimes affect the functioning of the factory. Same way our body also produces lot of harmful wastes. Some of them will be released through, stools, urines, and sweats. But most of the harmful wastes will be accumulated at some part of the body like Kidney. Kidney stone is a common disease occurring in many people.Kidney failures can cause problems to the blood purification purpose and death can happen.
Telomerase theory of aging
Discovered by scientists at the Geron Corporation, Telomerase Theory of Aging argues that telomeres (the sequences of nucleic acids extending from the ends of chromosomes), shorten every time a cell divides.
This shortening of telomeres is believed to lead to cellular damage due to the inability of the cell to duplicate itself correctly. Each time a cell divides it duplicates itself a little worse than the time before, thus this eventually leads to cellular dysfunction, aging and indeed death (Kleinsek Ph.D. ) We have the ability to either accelerate or slow sown the DNA damage. Those who have the ability to slow down the DNA damage may live much longer than those who have not such abilities. DNA can be repaired using artificial means up to certain extent which can delay the death. But under no circumstances, it is possible to avoid death as per the researches and findings till now.
Aging is a natural phenomenon incorporated to all the living things by nature in order to find spaces for the coming generation. Even though there are many biological theories are there with respect to aging and death, all of them unanimously agree that death is inevitable.
- “Biological Theories of Aging”. 16 March 2010.
- Gavrilov Leonid A and Gavrilova Natalia S. 2002. “Evolutionary Theories of Aging and Longevity”. 16 March 2010.
- Goldsmith, Theodore. C. 2009. “Theories of Biological Aging”. 16 March 2010.
- Kleinsek, Don Ph. D. “Theories of Aging”. 16 March 2010.
- http://www. antiaging-systems. com/agetheory. htm |