It seems that a lot of people are obsessed with the idea of immortality.
Qin Shi Huang, the first emperor of a united China (reigned 221-210 BCE), was obsessed with the idea of being immortal. So, he ordered his army to search for something that would make him immortal. Instead of living forever, Qin Shi Huang drank mercury and died from mercury poisoning. Obviously, drinking mercury won’t help us become immortal. But what, if anything, will?
A newborn will gain, on average, about 100 pounds by the time they are 20. Humans peak at that age. After that, there is a decline in their physical and mental performance, but this decline happens way too slowly for us to notice as its happening. And then, by the time we get to 60, our chances of dying doubles every eight years. This means, for instance, that a 68-year-old is two times more likely to die than a 60-year-old. The loss of a loved one is always very sad, and it can be especially difficult to deal with if the death is sudden.
One theory on why we age is called the cellular clock theory. This is the idea that cells only have a limited number of times that they can reproduce. Once a cell has reproduced as many times as it can, it starts to become damaged. DNA (deoxyribonucleic acid) is the blueprint of a living organism. DNA is made up of a random sequence of letters called base pairs. Adenine (abbreviated as A) pairs with thymine (T) and cytosine (C) pairs with guanine (G). DNA looks like a twisted ladder. If part of one side of the ladder has AAGCTC, then the other side of the ladder will be TTCGAG.
A chromosome (looks like an X) is made up of two strands of DNA(2 inches, 2 nanometers in width). Humans have 23 pairs of chromosomes — 46 in total. Telomeres are stretches of DNA that are at the bottom of chromosomes. They protect chromosomes from losing genes each time they replicate. They are essentially the aglets (plastic tips) of shoelaces. Each time a cell reproduces, the amount of telomere it has decreases. This is because when a cell divides, it makes copies of its chromosomes, which means the DNA strands (twisted ladders) unwind and separate and then an enzyme called DNA polymerase, with the help of pieces of RNA (ribonucleic acid), reads each side of the ladder and makes a corresponding base pair.
When the new strand is made, there needs to be more room for the RNA, so the telomere becomes shortened. A newborn’s telomeres can have around 8,000 base pairs and an older person’s telomeres can have around 1,500 base pairs. So, if we can figure out a way to prevent telomere shortening, we could essentially lengthen our lifespan.
But the thing is, we don’t know if telomere shortening is caused by aging or if aging is caused by telomere shortening. The enzyme telomerase adds base pairs at the ends of telomeres to counter telomere shortening. Scientists are working with having human cells divide forever using telomerase but applying that to actual humans is still something that, if it occurs, will happen in the future.
Since the 1600s, our life expectancy has increased by about 50 years due to things such as advancements in medicine (for example vaccines and antibiotics), better living conditions (for example, sanitation), and technology (for example, refrigerators).
Some scientists predict that our life expectancy will never go past 90 (it’s about 79 in the United States); but Richard Cawthon, a geneticist working with telomeres and telomerase, predicts that if all processes of aging could be eliminated and oxidative stress damage (free radical theory) could be repaired, humans could potentially live to be 1,000 years old. It isn’t immortality, but it’s pretty close!
Vaageesha Das is a junior at Morgantown High School.
Today’s information comes from:
- Bains, P. (2020, January 9). Exercise is key to living longer. Retrieved December 07, 2020, from https://www.allinahealth.org/healthysetgo/move/exercise-is-key-to-living-longer;
- Glancey, J. (2017, April 12). The army that conquered the world. Retrieved December 07, 2020, from https://www.bbc.com/culture/article/20170411-the-army-that-conquered-the-world;
- Learn. Genetics. (n.d.). Are Telomeres the Key to Aging and Cancer. Retrieved December 07, 2020, from https://learn.genetics.utah.edu/content/basics/telomeres/;
- Universal-Sci (Ed.). (2020, August 28). Can ageing really be ‘treated’ or ‘cured’? An evolutionary biologist explains – Universal-Sci. Retrieved December 07, 2020, from https://www.universal-sci.com/headlines/2020/08/27/can-ageing-really-be-treated-or-cured-an-evolutionary-biologist-explains.
