Why do we die?

Question

Scientifically speaking, why?

Answer 1

All our cells in our body divide by mitosis. All cells will eventually die so divided cells replace them. As you grow, more cells are being produced than the amount of cells dying out. (cells die because the mitochondria that makes energy for the cell becomes gradually inefficient.) At the midpoint of our age the amount of cells being produced by mitosis equals the amount of cells dying. Later on in life more cells will die than the replacement cells and we cannot get enough cells to keep going so we die.
Don't forget that cells are the building blocks of life. We need; cells to make tissues, tissues to make organs (skin and muscles), organs to create a system (e.g. the digestive system) and systems to make an organism.

Answer 2

Cells break down with age, eventually that sum total of all those cells breaking down results in weakness, sickness, disease and/or death---we call this aging.

Interestingly, you should browse some forums on nanotechnology and read what some scientists are proposing. Nanotechnology is the science of building things from the atom up. So some theorize it is technically possible to build small machines which would then be injected into our bodies just like a flu shot. These machines would proceed to repair our cells and keep them up to spec of an ideal, young human model.

According to these scientists, as long as cells are continually repaired the body keeps functioning. So, barring being hit by a bus or falling off a cliff, humans could live forever.

This is not science fiction. Nanotechnology is a fledgling science and the only barriers to this theory becoming reality are in engineering these "machines". Keep an eye on this in the next 40-60 years.

Answer 3

Scientifically speaking, our DNA is 'programmed' to die in two important ways. Certain cells do not divide to make new cells (except perhaps following certain physical injuries). Heart muscle and brain cells normally do not divide yet some are lost as we age. When cells divide the DNA (long helical strings of genetic code) can lose some code at the ends (split ends?) and only a certain approximate number of cell divisions are reasonably possible. This differs for different cell tissues. Man would not die if all damaged or aged cells were replaced with new original cells and unneeded accumulations of matter were cleaned out. From a practical point of view, we are born and develop with excess capacity like two lungs capable of oxygenating us at a full run or two kidneys capable of purifying our blood under extreme loads. Smoking and excessive drinking prematurely rob some of their excess capacity and finally of there minimally required capacity. Eat healthy and live longer.

Answer 4

We're not built to last - many people put 'to clear room' assuming that evolution somehow looks ahead to an overcrowded world - do these silly people honestly think any organic creature would develop safeguards to decrease its survival value? Such creatures would quickly go extinct.

In biological terms cell division over time wears us away - the cells have a kind of clock called a telomere which is shortened with each replication. If we could reprogram that with molecular technology this may help us live for longer. In evolutionary terms the answer is there is no need for us to live. Once you've had your children and they're able to survive on their own you might as well be dead. Your genes have their version of immortality - or at least the next stage of a massively long life. This is why various insects and spiders die after they breed - and why not? They have fulfilled their function in life which is to replicate their genes. Your genes may live forever, you won't.

Answer 5

Because of sin....

Things in the world are falling apart.

Because "it is appointed for all men, once to die, and then the judgement"

We were not created for death, but sin brought on death. God redeems us through his son Jesus if we accept the free gift and are born again by the Holy Spirit.

That may not sound scientific or intelligent enough for you...but it's important and true! The other folks on here answered you scientifically so I hope this helps too!

Answer 6

We have to. You may think that when your cells replicate, they completely replicate but taht's not true. You actually have a genetic strip inside your cells. This strip does not replicate so much as it splits in half. When your young, it replicates, when you stop growing, it ssplits in half. When this certain strip of DNA can no longer split in half, you stop regenerating new cells and you have to die because you are physically incapable of healing and replacing dead cells.

Of course there are other reasons but I've only just got over ten minutes until I'm no longer a part of teh Yahoo! Answers community. My answer, by the way, is completely genuine, you cna find it in a book called 'genes' by Brian J Ford. Now if you'll excuse me, I'm going to go adn do what I do best, beign a complete cow.

Answer 7

Death has many potential causes: disease, injury, poisoning, among others. Any of these may damage tissues and organs, and disturb the inner balance that allows vitality (homeostasis). Ultimately, every cause of death in animals does so by breaking the oxygen cycle, cutting off oxygen flow to the brain. All living creatures die, even if they have no particular affliction. Furthermore, every species has its own typical life expectancy. Humans, for example, don't usually pass the 100-year mark, even when they are generally healthy and living in a secure environment. In humans, similar to most mammals, one can discern a slow deterioration in the body's vitality, which eventually results in death.

Current research aims to discover the cause of the body's natural deterioration upon entering old age. Even though findings are generally inconclusive, several theories have been proposed. One theory proposes that the body's deterioration is caused by genetic reasons, as the human genome contains a self-destructive mechanism that kicks off after a specific length of time. Another theory suggests that there is a limit on the rate of cell division which ultimately leads to cell demise (see Telomere).[2] However, many studies show that a proper diet and nutrition together with regular physical activity can extend life expectancy.

In third world countries, inferior sanitary conditions and lack of access to medical technology makes death from infectious diseases more common than in developed countries. One such disease is tuberculosis, a bacterial disease which killed 1.7 million people in 2004.[3]

Answer 8

It's a good question. If you think about single-celled life froms, they never die naturally (although they can be killed); they have no fixed life-span.

But. multi-cellular life froms seem to all be subject to aging and death.

Some have specualted that it has something to do with telomeres (the highly repeptitive termination of a strand of DNA); telomeres are not reproduced during cell division, and so shorten with eatch succeeding episode. Eventually, they are so short the cell can no longer divide.

However, that explanation doesn't really work for specialized cells -- such as neurons and brain cells, that do not undergo individual replication.

Answer 9

with age the capacity of division of human cells decrease and so gradually growth of an organism comes to a hold.finally when the cells stop dividing all the activities of visceral organs stop and thus when systems come to a hold biological death occurs.

Answer 10

As we get older, the cells that our bodies produce are not as good. So the parts of our bodies start to fail. When vital organs fail, that's it!