Journal #2: Why We Age—And How We Can Stop It

In this ten-minute video from Scishow, Hank (the enthusiastic host who talks with many hand gestures) talks about immortality, or at least an enviably long lifespan, and the series of discoveries made about this particular topic. 

 

Now, there are a number of reasons as to why we age, the first being senescence (an official term for aging). Senescence takes place after sexual maturity (because again, we are only good for reproduction), and as it progresses on we lose the ability to combat physical stress, maintain homeostasis and fight off illnesses. However, some species do lack the symptoms of aging; in other words, they are negligibly senescence. Essentially they maintain a level of fitness until diseases, predations or accidents occur. 

On a cellular level, senescence could be viewed as constantly dividing somatic cells that are programmed with a fixed biological timing—the Hayflick limit. The Hayflick Limit indicates the amount of cell divisions each one could undergo; furthermore, these “expiration dates” get shorter with age, and as our cells practically have death automated into them—we also face an imminent death. 

Sorry, Twilight fans

And here an obvious question rises up: what is the cause of the Hayflick Limit?

(and more importantly, how can we overcome it so we can live forever?)

The answer is most likely to be chromosomes. Cells are no longer viable when it is inept to replicate telomeres, the non-coding DNA on the end of chromosomes that prevent copying errors. Along with that, telomeres shorten with every division, until it is finally too short to protect the chromosome any longer—rendering the cell useless. 

Here, another point arises. If scientist were to fiddle around with the chromosomes to sustain the telomeres, then what is stopping us from immortality? 

Telomeres

And that is precisely the problem: prolonging telomeres is very much possible, and is already practiced by one type of cells that can create its own and divide infinitely without damage to the chromosomes: cancer cells. Their rapid dividing is what causes malignant tumors; successfully ending the hope that it holds the answer to our universal wish.  

Firstly, to bridge this idea to my Biology class, is the cell division bit.  The Hayflick Limit is both a remarkable (and frustrating) aspect of the cell division business, and it does provoke thoughts on what other discoveries are there on the division of cells. Another mentioned detail is homeostasis, the system of regulating the internal environment of human, and it's eventual fate into becoming one of the senescence's causality.

The reason this concept made a fascinating video to watch, is solely due to the lure of living forever. For hundreds of years, humans have been intrigued by such a notion; from the Philosopher’s Stone to Dracula, there is no doubt that it will continually be one of the most sought-after ideas. It is certainly possible (to a certain extent) seeing as the Hydra is biologically immortal, and other negligibly senescence species do exist. However, knowing whether or not if the human body (and its materials) is physically able to achieve that with medical engineering, on whether or not it could overcome the limits in which we live as of present—could possibly be centuries of research. Of course, I would much rather know the possibility within this lifetime, as well as the way it could be achieved, though I have a feeling if it were possible, it would be a franchise. But again, there's the if, and whether or not we'd be fortunate enough to even catch a glimpse.

Oh well.

Can't do anything about that

Citations

Author Name: Hank Green/ Scishow
Title of Web Document:  Why We Age--And How We Can Stop It
Title of the Hoisting Website: YouTube
Publishing Organization: YouTube
Date Rretrieved: Nov 3rd
Date: October 21st, 2012