Title. Why do our bodies stop growing at one point and begin to decline in function? If the purpose of life is to live and reproduce, wouldn’t it make more sense to continually evolve and live forever? Also don’t our cells constantly regenerate? So if they do then why do they start to die out?
In: Biology
Life doesn’t have a purpose the way you’re describing. Life on earth came about because of random chance. some species thrive, some species go extinct, there’s no plan or guiding hand. I pretty much all living things die because the DNA that forms the basis for living things degrades over time when cells divide. Besides, if everything lived forever, that would be a nightmare. And the planet would over populate in a few generations to the point where all plant life was gone, and then everything that eats meat would start consuming each other with no herbivores to fill that part of the food web. You would cause a mass extinction within decades.
DNA is a recipe that describes how to make that cells in your body. Each time your body makes a new cell, it follows the instructions in the DNA to make it. This includes creating a new copy of the DNA, which introduces a problem. What happens in the new copy isn’t completely right? You get cells that don’t function correctly and can actively harm the body around them. The most common of these are the various kinds of Cancers. Strains of our DNA is capped with a special kind of proteins called Telomeres which helps protects them from damage during coping, but the Telomeres themselves get shorted by a little bit each time they are copied. Once the Telomeres have become exhausted, your DNA becomes much more likely to be damaged, resulting in illness and death.
1. cells take on damage over time (UV, toxins, metabolic byproducts)
2. replication errors in DNA
3. telomere shortening (every time a cell divides the telomeres that help it divide get shorter)
Latest Answers