Cellular Aging Theory, And The Wear And Tear Theory

Humans undergo several stages during their lifetime including growth, development, reproduction and senescence. Senescence is defined as the deteriorative biological changes that organisms experience as they age eventually leading to death. These changes include low metabolism, a weak immune system, memory loss, poor vision and loss of hearing. Senescence begins in humans during their post-reproductive years. However, gerontology research has shown that individuals who reproduce late have longer life spans compared to individuals who reproduce early. Nonetheless, it does not indicate that senescence is inevitable. All organisms experience senescence,

Now we know that progeria is a genetic mutation that causes what seems like accelerated ageing but what exactly is ageing? And what causes it? Well no one knows for sure but one idea is linked to Progeria. Progeria is caused by a mutation in Lamina A (you will learn more about this in the next paragraph) which misshapes the cells nuclei and causes stem cells to be unable to replace the old, worn, cells leading to deterioration over time (Travis, J. (2003). An easier way to understand this is shown through the words of Shaoni Bhattacharya in her essay The children who grow old before they grow up whenever she states “The gene encodes lamin A, a protein found in a cell's nucleus. This is a major part of the lamina, a kind of scaffolding on the inner side of the nuclear envelope. It is also associated with DNA itself. There is still a lot to discover about

While anti-aging is a field of interest, there are some challenges that come about since aging is a complicated process with no definitive answer. Due to factors

Every time a cell divides we lose a telomere, making it shorter. When it eventually gets too short the cell dies as it can longer divide. Each time the telomere gets shorter the ageing process takes a step in one direction, our chance of cancer goes up. This happens in all of our cells that regenerate, like the ones filled with fibers such as collagen and elastin, that good stuff that keeps us looking young. So, the more years we are alive, the more times our cells divide shortening our telomeres and before

Using this characteristic, we could seek ways to conquer aging by changing the environment we live in. Experiments had done on C.elegans, a tiny worm with 14 days of life. By damaging an age control hormone called Daf-2, biochemist Cynthia Kenyon doubled C.elegance’s lifespan to 28 days. More experiments were conducted until she concluded that hormones like Insulin, IGF-1, and Daf-2 control aging. Dig into the discovery, she then found the key factor behind- a gene regulation protein called FOXO. This protein is activated when receiving signals of decreasing hormone levels. Importantly, one way to cause a reduction in hormone is harsh environmental conditions. When animals and human suffer from a shortage of food supply, FOXO triggers functions like antioxidant, caregivers or DNA repair, and ultimately extend lifespan (Kenyon, 2011).This is a perfect example showing that environmental interactions could affect human behaviors, therefore changing the rate of

Ageing, “the gradual decline in functions observed over time” (Rehman, 2016). Ageing is the result of genetic mutations that build up over time and make it harder for the cell to copy DNA. Every three nucleotide base pairs code for one amino acid, so by changing just one nucleotide can change the amino acid and the amino acid builds a different protein and that protein does a different job than was intended before the base pair change. The DNA copying that takes place in a cell during mitosis can be compared to a metaphor of a copying machine, one jam builds up and jams other copies and the machine doesn’t work as effectively. This paper jam is ageing, mitosis slows down and takes longer to produce cells and thus intern causes a domino effect,

In this week’s assignment, I’ve learned several things about how aging affects you physically and mentally.  With my personal growth, this week’s assignment it made me realize why we age and we get older. It is a mystery and there are many theories about how we age.  This expanded my knowledge because it forced me to look into why our bodies and minds age.  I did not know about the theories of aging and how we age, this a new concept and something I did not have an understanding about.  I believed it was the way life evolved. You’re born as an infant that develops into a young person that matures into an adult. The most valuable lesson I’ve learned, there are four theories of aging. The theories are 1. Oxidative stress - the body inability

Aging is a complex and multifactorial process that has induced several new and modified theories to explain the aging process. Overall, while multiple theories of aging have been proposed and studied, currently there is no consensus; many of the proposed theories have been found to interact with each other in a complex way. By understanding the existing and testing new comprehensive aging theories, it may be possible to understand the process of aging more fully, and thus improve longevity and quality of life of all

The current state of genetically altering life spans is mostly based of the last two decade of research involving animal models. The evidence of the research is showing that aging is more complicated than previously thought. The evidence also shows that the life span of these animal models can be manipulated. There has been an increased effort among researchers to break down the genetic basis of aging, or senescence, which is the harmful side of increasing age. Researchers have made progress with the use of animal models. The research from these experiments has shown that by genetically manipulating the DNA of these models can alter their life span. These findings raise the question on whether or not these practices can benefit human life span.

Senescence in the phrase “effects of senescence on physiology”, refers to the complex process of ageing that eventually leads to death. Therefore, effects of senescence to physiology refers to how biological processes and organs within the human body change as a result of one growing old (Shock, 2015). In addition, the author points out that the performance of organs such as heart, kidneys, brains or lungs decreases as a result of cell death due to the decreased ability of the body to produce or repair cells- when one is growing old. Shock (2015) mentions that during senescence the remaining cells in the elderly body may not perform as well as those in a young individual thus, taking enzymes in the elderly body to carry out chemical reactions.

Aging is simply the procedure of growing old. Ironically, the process is not that simple. With enhanced medicinal attention and living circumstances in developed nations have improved both healthiness and life expectation, from approximately 50 years in the early 1900s to over 80 years at the current time. Nevertheless, age is the foremost risk factor for the primary devastating and life-threatening conditions such as diseases related to loss of neurologic functions, cancer, and heart and blood vessels.

Telomeres are directly correlated to the aging of a human body. Although some people might think that shorter telomere lengths are detrimental, the natural shortening of these telomeres are essential to healthy and normal aging. It is natural for cells to divide through mitosis, but each time cells are split telomeres are lost through the process. This is why the telomere maintenance system was evolved to protect the ends of chromosomes (Prescott, Kraft, & Chasman, 2011). Every time a cell is divided, its telomeres are weakened, and stress can accelerate this weakening, and biologically age the person. As a

In particular: a) species which show no aging (“animals with negligible senescence”) show the same telomerase activity at any age and have no cancer problem, as demonstrated by their constant mortality rate at any age; b) in our species, studied in wild conditions, the increase in age-related mortality is precedent to cancer-related deaths cases and it is impossible that defenses against cancer kill before cancer can develop; c) shortened telomeres, as a result of telomerase inactivity, cause dysfunctional telomere-induced instability and so the likelihood of cancer increases; d) in normal mice, telomerase expression delays aging but does not increase cancer risk.

During each and every cell replication, chromosomes shrink by a small, but noticeable amount. Because of this, telomeres cap the ends to protect the coding regions of the chromosomes. With each generation of DNA, more and more of the telomere disappears. An enzyme slowly rebuilds them, but it cannot keep up with the degradation during chromosome replication. Eventually the shortened telomeres cause the cell to go through apoptosis (Pierce 2014). Because telomeres are one cause of cell death, it is hypothesized that telomere size can determine the health and age of an individual. Research has shown a correlation between telomere length and chronic disease. Those with chronic diseases usually have significantly shorter telomeres. This raises the questions of what the correlation means. Chronic disease could shorten the telomeres, or short telomeres could cause chronic disease. Another hypothesis exists that shortened telomeres and chronic disease are both caused by another force; they occur simultaneously, but one does not necessarily cause the other. Researchers have also seen a correlation between telomere length and age. Physical age may be derived from the number of cells that have undergone apoptosis. There are a number of things that we can do to prevent telomere reduction. Diet and exercise both play a key role in this. Things that are “bad” for us, such as smoking and stress, increases the rate at which telomeres shorten. By

Causes of aging are very uncertain. Besides, there are several factors which predispose an individual to premature aging. Current theories suggest that this process occurs to due to cellular damage such as DNA oxidation by free radicals causing