if body cells are always replaced whenever they die, how comes living things die.?

Question

what is the meaning of death.what gives us the strengths to do all those things that you do.why doctors fail to prevent death?

Answer 1

Death is defined differently depending on what institution or book you are accessing. Usually though, death is the complete and irreversible sesation of a heart beat and the death of brain activity (along with these, the lungs and other vital organs follow).

If our life solemnly depended on the functioning of cells, then you are right, it would not make sense to see people dying. But the human body, composed of several trillions of cells, needs to maintin certain levels of oxygen in order to keep these cells alive and in constant reproduction. So consider the following case, a person starts drowning, therefore he starts lacking oxygen. The lack of oxygen will eventaully lead to cells dying and thus the failure of the organ systems. After that, if the person isnt rescued, the whole body dies, thus the person dies. See how the human body doesn not only depend on cells in order to live? Thats why we die.

Also, as we age, the funcion of our cells becomes less and less productive. As we get old, so do our cells and guess what, they die too and are not always replaced. Eventually, the replacement of cells stops at some point.

So what gives us the strenght to do things? Its cells yes, but from a bigger point of view, its the nutrition that we give these cells. Cells run on ATP just like cars run on gas. If we eat the appropiate things, our cells will be stronger, and our bodies will too. Thus ATP is actual energy, energy that our cells provide to our tissues, to our organs, to our organ systems and to us, as organisms-humans.

The reason why doctors cannot prevent death is simple, they cannot reverse the course of nature that our primary parents, Adam and Eve left for us to inheret. They sinned, inhereted death and illnesses and so did we. Although medical doctors can often make things better and help us feel that way too, expecting them to come up for a solution to death is a little to off, perhaps out of their league.

Answer 2

1

Answer 3

Human body is a perishable DNA carrier, thats all ! our job is bring variety in our DNA by coupling with a better variety and then pass it on. The moment we do it, technically our job is over.
Death is nothing but the body giving up its functions due to excessive wear and tear! our heart keeps pumping continuously and gets tired, also the chemicals like hormones, acids and free radicals although help our functioning turn killers as they alter our genetic code and the cells go into a suicidal mode. the funny part is, the suicidal mode is the cell forgets to kill itself, that is when we start aging, like the skin hanging poor eye sight. if we dont let the cell die new cells cannot be produced. if new cells cannot be produced the old cells give up as they get tired of over usage and finally we stop functioning---that is called death.

Answer 4

As we age, our DNA gets corrupted. That's why skin in old people - even the new cells - doesn't look like baby skin.

We die because the delicate balance that keeps us alive eventually is overcome.

Why do doctors fail to prevent death? I am a doctor - heck, we can't even get people to quit smoking, let alone prevent death. All we can do is offer advice on waht you can do to prolong and improve the life you have.

Answer 5

Living things die because cells can only split so many times and as the years go on they not only don't spilt as much but the slow down. There really isn't anything a doctor can do to keep cell from getting used up its just nature.

Answer 6

nice question very very short answer is that, when cells replicate mitosis the copy is not perfect 1 in 10^8 of the bases may be wrong, this problem is continued whenever the cell divides again, and the mistakes build up, so cells become less good at what they were supposed to do, so death is unavoidable, really, you can try and cure individual organs that mistakes seem to showing in but eventually it all goes wrong and you die,

Answer 7

As we age the cells loose their ability to reproduce and make mistakes in copying themselves, the older you are the worse it gets. A couple of short articles from New Scientist below
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In brief : Wasting away

* 03 January 1998
* From New Scientist Print Edition.


"KILLER factors" that trigger healthy cells to commit suicide could explain why muscles waste away so quickly in the elderly, a scientist told the American Society for Cell Biology in Washington DC last month.

Old muscles lose mass even though they have enough regenerative cells to replace dying tissue. To try to understand why, Eugenia Wang of McGill University in Montreal, Canada, took the liquid surrounding dying muscle cells and added it to healthy muscle cells.

Surprisingly, the healthy cells committed suicide due to factors secreted by the dying cells. Wang believes the sudden decline in muscle cells could be activated when aging muscle achieves a critical level of dying fibres. "When the cells try to regenerate, they get killed," she says.


Shorter telomeres mean shorter life

* 00:01 31 January 2002
* NewScientist.com news service

Baby Bio

Old people can expect to die sooner if they have shorter telomeres, pieces of DNA that protect the ends of chromosomes.

Researchers have long suspected that telomeres act as molecular clocks governing the process of ageing in cells, but until now nobody has proven the link.

"There has been a lot of hot air and prediction based on animal models. This really is the first time that facts have replaced that," says Elizabeth Blackburn of the University of California, San Francisco, discoverer of the telomere-building enzyme telomerase. But she cautions that the new research does not necessarily imply that shortened telomeres cause early death.

Some cloned mammals, such as the sheep Dolly, have shorter telomeres than other animals of the same age, leading some scientists to speculate that they will have shorter lifespans.
Unravelled shoelaces

Geneticist Richard Cawthon and colleagues at the University of Utah measured the telomeres in a randomly-chosen group of 150 patients aged 60 or over. Those with shorter telomeres were eight times as likely to die from an infectious disease and three times more likely to suffer a fatal heart attack.

A telomere is a repeated sequence of five bases that preserves the integrity of genes during DNA replication, rather like the glue that prevents the ends of shoelaces unravelling.

Its length at birth varies from person to person. But each time cells replicate, daughter cells have slightly shorter telomeres than their parents. Over time, after many replications, a DNA strand's sealant erodes.

In healthy people, telomeres do not shrink significantly until old age because the enzyme telomerase ensures regeneration. But eventually telomeres get so short that the DNA strands either stop replicating or, worse still, start fusing together, often encouraging tumours to grow.
Slow response

White blood cells rely on their ability to replicate quickly to mount attacks on infections. Retarded replication caused by shorter telomeres might explain why those patients were much more likely to die of an infectious disease, says Cawthon.

He admits that it is not clear whether short telomeres actually cause age-related diseases and death or whether they are just a symptom of some other process responsible for aging. Either way, there are other forces at work - earth worms and fruit flies get old long before their telomeres shrink significantly.

Inducing telomere growth by somehow injecting telomerase might seem like a potential way to extend life. But this would risk causing cells to replicate uncontrollably, leading to cancer.

In fact, Titia De Lange, a telomere expert at Rockefeller University, New York, believes the correlation between telomere shrinkage and old age has evolved to retard cell replication. This would provide a "tumour suppressor pathway" in the older cells most likely to turn cancerous.

Journal reference: The Lancet (vol 361, p 393)

Answer 8

When they are replaced genetic imperfections occur. So, over time these genetic imperfections accumulate to create ageing.

Why do you try to make doctors responsible for not preventing death? You obviously have no faith. It's lack of faith that gives medical researches the excuse they need to enter into immoral research.

Answer 9

death is the punishment for sin my dear,scientist are saying that our bones replenish themselves to only be 20 years old no matter how old we get! and you are right if our cells gets replaced as they die why do we die?death my seem cruel,but what if everyone ever born was still alive?where we we all fit?

Answer 10

B'cuz cells r not created from nowhere. Every tissue has its capacity to regenerate and as people grow older, this regenerating power comes down and eventually goes out.