Reason's Why Humans Can Live to at least 120 Years - Essay Example

? REASONS WHY HUMANS CAN LIVE TO AT LEAST 120 YEARS Since time immemorial, human beings have had the desire to live forever without death being a part of their lives. To understand what affects the life span of humans and other organisms as well, we need to understand the anatomy and physiology of their bodies. Anatomy is the study of the body’s structure while physiology studies the functions of the body organs. The human body consists of well-organized cells that perform different functions. As people grow, wastes in their bodies accumulate, in turn, stopping the underlying cells from working properly making them age at a faster rate. Scientists have analysed these for a long time through researching what organisms should do to enjoy healthy lives or live longer. In this discussion, I support their arguments by analysing their research findings. Through research estimates, the maximum years a human can live in this century are 120 years (Rana, and Ross, 2005). Scientists examined the composition and structure of the body to determine the possibility of increasing the lifespan of human. They have used technology and laboratory observations on other species like rats to find ways of reducing illnesses, and genetic disorders, subsequently, increasing the time human beings live. Different organisms and species have varying life spans. According to research, life expectancy depends on factors like the cell metabolism, body and brain size, the environment and genetic make-up among other things. Among these factors, it is clear that the metabolic rate of an organism is a correlation between the metabolic rate and life span. For example, the tortoise and other slow moving organisms have a longer life span than fast moving organisms. This is because they are less active and use reduced levels of energy compared to their counterparts. This makes them have a reduced metabolic rate (Rana, and Ross, 2005). There are theories that scientists and researchers have used to make their conclusions, and include Wear-and-Tear Theory, Autoimmune Theory, Cross-Linkage Theory, Free-radical theory, Aging-Clock Theory and the Cellular Theory. These theories are based either on fate or chance. Theories based on chance look at the external factors that alter the body’s anatomy as time moves by. An example of an alteration is mutation. Theories based on fate looks at internal factors that may increase the rate of aging such as the genetic make–up of the organism. The wear and tear theory implies that the degradation of cells in the body increases the chance of diseases and other complications, which concurrently reduce the life span. There are two main categories of cells, which are the germic plasma and somatic cells. The germic cells are made up of the sperms and egg cells. The rest of the cells are somatic cells. The cells in the human body often undergo wear and tear and eventually die. When this happens, the worn out cells are replaced with new ones while the torn cells are repaired. The Autoimmune theory studies the relationship found between the immune system and aging. The immune system produces antibodies that help the body defend itself against the attack of foreign disease causing bodies (SAGE, N. D.). As a person grows, their immune system weakens thus increasing their susceptibility to diseases. As a result, it comes a time when the immune system cannot differentiate between the invading bodies to cells of the body. The Aging-Clock theory views the life span of humans as a sequence of activities from the time of birth until death. Hormones that are active at different times of growth control the human body. The most researched theory is that of the Free Radicals. Free radicals are atoms produced during oxidation and contain at least one unpaired hydrogen atom. Free radicals are highly reactive and unstable and cannot survive on their own. They pair with any available elements to increase their stability. During these reactions, they mutate the body’s’ cells and damage the cellular composition. Free radicals are known to cause serious diseases like cancer; heart conditions, rheumatoid arthritis and osteoporosis thus increase the rate of aging. For example, to cause heart problems, the free radicals pair with fat cells, eventually forming oxidized fat. These oxidized fats settle along the walls of the artery and blocked them. Blocking of arteries reduces the amount of blood flowing to the heart and can eventually damaging the heart. The cellular theory of aging argues that the capability of cellular division reduces as one grows reaching a limit known as the Hayflick limit at some point. The Hayflick limit refers to the maximum number of times a cell divides before it stops. Research done on the tissues of a foetus and a 70 year old by Leonard Hay flick, in 1965, showed that cellular division in the foetus had a limit of 100 times unlike that of from the older person which divided a maximum of 30 times (SAGE, N. D.). Scientists developed two main approaches towards increasing the life span of human to a maximum of 120 or more. These approaches are the caloric restriction method and the genetic approach. The caloric restriction limits the amount of calories consumed by between 30 – 40%. Research done on rats subjects to a reduced caloric diet found that the rats lived way much longer than it was expected. If the same is applied to humans, people can live even longer by up to 30 years. An ideal diet for this contains high nutritious well balanced food with reduced calories. This approach encourages the intake of supplements since they are digested faster. Antioxidants are the best supplement to reduce the rate of aging since they fight off the free disease causing radicals. Genetic experiments done on organisms like yeast have shown tremendous possibility of the extension of life. This is through altering the genetic composition by replacing the genes causing aging with modified ones. With these, scientists have; therefore, proven beyond doubt that life span can be increased. Additionally, the DNA forms a key player when it comes to aging. In relation to this, scientific research has been performed on mice’s DNA’s telomeres. The research deduced on telomeres, which are the crucial terminal ends of the DNA located on each chromosome shows that they not only keep the chromosomes from attaching to each other but also have a vital role in the aging of cells. Scientists have made strong conclusions that shrinkage of the telomeres results to aging of the cells. On the other hand, studies of telomeres in mice have proved to produce encouraging results as scientists tweak the mice’s telomeres, in turn reversing aging and increasing the mice’s life span. The results are encouraging though rodents are still far from humans in terms of anatomy similarity, but with continuous research on tweaking telomeres, eventually reversing of human aging will be possible (Kimball, 2011). References Kimball J. (2011). Telomeres. Retrieved on April 1 2012 from >http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/T/Telomeres.html< Rana, F. R., & Ross, H. (2005). Long Life Spans: "Adam Lived 930 Years and Then He Died" New Discoveries in the Biochemistry of Aging Support the Biblical Record. Retrieved on March 29 2012 from >http://www.godandscience.org/apologetics/longlife.html< SAGE. (n. d.) Why Do Our Bodies Grow Old? Retrieved on March 29 2012 from >http://www.sagepub.com/upm-data/44595_2.pdf Read More