The difference between life and non life

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The difference between life and non life

Postby MINARAS on August 31st, 2007, 4:00 pm 

When somebody is studying the phenomenon of viruses ,he can see that when viruses are not coming in contact with a host organism, they are a sum of chemical compounds that not fulfill the criteria to be considered as life.While on the other hand they start reacting with a host, or in other words they start making chemical reactions with the compounds of the host,they become alive.The same thing happen with prions ,which are proteinaceous compounds that while they react with proteins of the host, they become alive in a way.

Lets hypothesize that we make the hypothesis that:No living organism is possible to remain unchanged structurally.Lets hypothesize that this rule is principal in nature and nothing could go beyond it or prove that it is untrue.

What would that mean to the way that we see the world?

First of all lets make clear what we mean: An organism that would remain unchanged structurally dyring a very small period of time,would be considered as not living for that period. When we say unchanged we mean of course that there are not taking place chemical reaction inside it.Maybe there is a single cell inside an organism that is unchanged,but the rest of the cells are changing. We say then that this organism has a dead cell.,but the organism as a whole is alive.Maybe this cell would be able to regain life if it react with the appropriate signals. But maybe not.

If we want to see the consequences of our hypothesis in the nature we meet the question:what is the least that can be considered as life?For example, a mitochondrion can be considered life according to what we said, but a simple chemical molecule cannot,unless it reacts with another molecule or substance.At the moment of the reaction these two substances are the least that is considerd life.So, a simple chemical reaction as long as it happens ,is the simpliest form of life, or else, the sparkle of life.That means that the superior organisms as well as all the organism is a summation of chemical reactions.

The advantages of the hypethesis that we made is that we can explain successfully the prions and the viruses.

Another important consequence of the hypothesis is this:Living creatures are the sum of their chemical reactions as we said.While they are getting older,they are suffering a process that is called aging.They are changing especially structurally.Obviously they are getting different.That means that the chemical reactions that are composing their body,are different from that that were before.If the chemical reaction were remaining unchanged forever,then the body would be the same,and that means that the body would stay forever young and forever alive.

Lets see now a simple chemical reaction A+B—}C+D.Lets consider that C and D are gases and are expelled from the place of the reaction.The quantity of A and B will get lesser and lesser because they are becoming C and D,Or else they are suffering a chemical transformation.

Lets see now another chemical reaction:A+B---}C+D--}E+F

Lets consider that E and F are gasses.That means that the quantities of A,B,C,D will be lowering unless we put in the mixture exactly the quantities of A and B that is being transformed into C and D every moment.So there is an exact amount, as well as exact rhythm of adding A and B that would keep the reaction unchangeable.Lets consider now a very simple organism that is composed from the reactions :A+B--}C+D--}E+F…………--}Y+Z.Lets say that A and B are food supplements and Y and Z are compounds expelled from the organism.Of course the real organisms are much more complicated.If that organism eat theoretically a certain amount of food in acertain way, then the reactions of this organism would remained the same forever.[C,D,E,F……are all compounds of the organism.].If we didn't give the exact food ,then the reaction would change ,dependently on the how far we are from that ideal food .In the same manner we can say that all living organisms are a sum of chemical reactions that start with digestion,and end with the waste products of metabolism.

As a result we can say that in a theoretical basis,if an orgasism eated exactly a certain amount,quality and quantity of foods in acertain way,then it could prevent the changing of its reactions and as a result it could prevent the aging process,expanding its lifespan.Of course this is something very difficult to happen in real life because there are numerous things that plays their role and of course things are not that simple.

One important clue that suggests that what we said is true, is the recent discovery that living organisms that follow a calorie restricted diet,can expand their lifetime, in some cases as long as 60 per cent.This is not a proof that what we said is true,but it is positive to find that the changing of caloric menu has as a result a change in the lifespan.Perhaps a certain diet causes an ever greater expansion.It remains to be proved…………..

The new hypothesis also says that life existed before the first cell,in the form of chemical reactions………………………see also the role of light in the creation and evolution of life……………………TO BE CONTINUED
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Re: THE DIFFERENCE BETWEEN LIFE AND NON LIFE

Postby lucaspa on September 7th, 2007, 1:27 pm 

MINARAS wrote: Lets hypothesize that we make the hypothesis that:No living organism is possible to remain unchanged structurally.Lets hypothesize that this rule is principal in nature and nothing could go beyond it or prove that it is untrue.

What would that mean to the way that we see the world?

First of all lets make clear what we mean: An organism that would remain unchanged structurally dyring a very small period of time,would be considered as not living for that period.


You made this much more complicated than it is.

In order to be "alive" an entity must exhibit ALL the following characteristics:
1. Metabolism (which includes catabolism AND anabolism)
2. Growth.
3. Response to stimuli
4. Reproduction.

Viruses and prions are NOT going from non-life to life, but instead are going from living organisms to non-living by letting other organisms -- their hosts -- perform some of the basic functions. In the case of both, it is metabolism and reproduction. Neither prions nor viruses can metabolize nor reproduce on their own. They must coopt the processes in living cells.

By the criteria above, mitochondria are not "alive". They can't reproduce by themselves but need DNA that is in the nucleus of the eukaryotic cell.

By your criteria, fire is alive. After all, it is constantly changing via chemical reactions. By the criteria above, fire is not alive. Because fire lacks anabolism.

Another important consequence of the hypothesis is this:Living creatures are the sum of their chemical reactions as we said.


This is also a consequence of other hypotheses. So the consequence is not unique to your hypothesis.

They are changing especially structurally.Obviously they are getting different.That means that the chemical reactions that are composing their body,are different from that that were before.If the chemical reaction were remaining unchanged forever,then the body would be the same,and that means that the body would stay forever young and forever alive.


Now you went the other way and got way too simple. Remember, bacteria don't age, do they? Aging is a property of multicellular organisms, not unicellular ones. Only a FEW of the chemical reactions are changing in the cells in our bodies. And, in some cells -- the primitive undifferentiated stem cells -- the reactions are not changing at all. We can isolate stem cells from 90 year old humans that are identical in capabilities to the stem cells from 1 day olds. Not only "can", but have.

The new hypothesis also says that life existed before the first cell,in the form of chemical reactions


Again, this "consequence" is not unique to this hypothesis. The RNA World hypothesis has long stated that "life" existed before cells. In this hypothesis, "life" is a set of RNA molecules that catalyze their own synthesis.
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Re: THE DIFFERENCE BETWEEN LIFE AND NON LIFE

Postby BioWizard on September 7th, 2007, 10:15 pm 

lucaspa wrote:Now you went the other way and got way too simple. Remember, bacteria don't age, do they? Aging is a property of multicellular organisms, not unicellular ones. Only a FEW of the chemical reactions are changing in the cells in our bodies. And, in some cells -- the primitive undifferentiated stem cells -- the reactions are not changing at all. We can isolate stem cells from 90 year old humans that are identical in capabilities to the stem cells from 1 day olds. Not only "can", but have.


You hit the nail on the head there. Aging is a cellular program, not passive entropic decay of cells, and it was evolved to serve certain functions in multicellular organisms, which may be beyond the scope of this discussion.

Although interestingly, I saw a report somewhere a few years ago that said something about bacterial division being not 100% symmetrical, and that bacteria can concentrate molecular toxins in one of the daughter cells, and so after some generations, the toxins levels get too high and the daughter that ends up with them dies. They described it as a form of unicellular aging, which of course I don't agree with. I can't confirm the validity of their results either.
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Postby goingtothedogs on September 8th, 2007, 2:25 am 

Bio, I read a book a while ago about this which really fascinated me. It was titled "Power, Sex and Suicide. Mitochondria and the Meaning of Life." by Nick Lane

The broad subject of the book is how our use of a eucaryotic/multicellular life and mitochondria in particular enables us to "live in the fast lane" with an oxygen powered lifestyle, but that part of the price we pay for that is the link between sex and death. It went quite deeply into the need for a cell to subordinate it's individuality for the common good of the body and the ways in which this is enforced.

It's a book I intend to read again because although it very interesting indeed, I didn't entirely "get it".

If you're feeling creative at some point, I'd really appreciate you giving a bit of background on the subject; in a new thread perhaps.



As an aside, I couldn't recall the exact book title, so I was searching Amazon. You can imagine some of the books it brought up searching under words like "power" "sex" and "death"
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Postby BioWizard on September 8th, 2007, 9:17 am 

goingtothedogs wrote:Bio, I read a book a while ago about this which really fascinated me. It was titled "Power, Sex and Suicide. Mitochondria and the Meaning of Life." by Nick Lane


Incidentally, it's the next book on my readng list. It was suggested to us by the lecturer in a course I'm taking. The course is on mitochondria - everything mitochondria. We can read it together and discuss it in the books forum. That'll have to wait though till I'm done with my proposal and also Lincoln's book.
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Postby goingtothedogs on September 8th, 2007, 9:37 am 

Ah thanks Bio. That'd be great.

Let me know when you're ready and I'll dig it out.
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Re: THE DIFFERENCE BETWEEN LIFE AND NON LIFE

Postby lucaspa on September 9th, 2007, 12:46 pm 

BioWizard wrote:You hit the nail on the head there. Aging is a cellular program, not passive entropic decay of cells, and it was evolved to serve certain functions in multicellular organisms, which may be beyond the scope of this discussion.


Part of aging seems to be a cellular program. That is, differentiated cells are programmed for a certain number of cell divisions before they apoptose and die. It's called "Hayflick's number" after Leonard Hayflick. The number varies from species to species. For humans it is about 50. Data indicates that it is the telomeres and levels of telomerase that provide Hayflick's number.

Some adult stem cells do not seem to obey Hayflick's number. The multipotent adult stem cells that I work with, for instance, have gone over 150 cell doublings and seem fine.

Another part of aging is accumulation of damage due to oxidation of lipids, proteins, and DNA and damage to DNA itself thru methylation and other chemical reactions.

Remember, natural selection is pretty much done with us after we have kids. So the mechanisms to protect cells from oxidative and other damage need only do well enough to get the individual thru having kids that survive to have their own kids. For humans that is about 35-40. After that we are going on momentum.

Although interestingly, I saw a report somewhere a few years ago that said something about bacterial division being not 100% symmetrical, and that bacteria can concentrate molecular toxins in one of the daughter cells, and so after some generations, the toxins levels get too high and the daughter that ends up with them dies. They described it as a form of unicellular aging, which of course I don't agree with. I can't confirm the validity of their results either.


Can you at least do a PubMed search and see if you can find the paper? That would help.
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Postby lucaspa on September 9th, 2007, 12:48 pm 

BioWizard wrote:Incidentally, it's the next book on my readng list. It was suggested to us by the lecturer in a course I'm taking. The course is on mitochondria - everything mitochondria. We can read it together and discuss it in the books forum. That'll have to wait though till I'm done with my proposal and also Lincoln's book.


Do you have any reading in that course on mitochondria replication? I'm finding that very difficult to fine either in PubMed or in books. Thanks.
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Postby lucaspa on September 9th, 2007, 12:56 pm 

goingtothedogs wrote:Bio, I read a book a while ago about this which really fascinated me. It was titled "Power, Sex and Suicide. Mitochondria and the Meaning of Life." by Nick Lane

The broad subject of the book is how our use of a eucaryotic/multicellular life and mitochondria in particular enables us to "live in the fast lane" with an oxygen powered lifestyle, but that part of the price we pay for that is the link between sex and death.


I'm not sure I get this. There are many unicellular organisms that are aerobic -- "oxygen powered lifestyle". Shoot, the ancestor of mitochondria had an "oxygen powered lifestyle". :)

It went quite deeply into the need for a cell to subordinate it's individuality for the common good of the body and the ways in which this is enforced.


This sounds way too teleological. Even once an organism is multicellular, it doesn't necessarily reproduce sexually. Many multicellular organisms reproduce by budding. On the other side, the unicellular amoeba Dictolystelium uses sexual reproduction.

Sexual reproduction has the advantage of introducing vast new levels of variation into a population -- by recombination. The disadvantage may be the death of individual. Or perhaps that is an advantage. Any species reproduces at a rate that exceeds the capacity of the environment. If there were no death, that would simply happen faster and the new variations would not be available.

You can read a bit on the evolution of sexual reproduction in a special section in Science: Evolution of Sex. Science 281: 1979-2010, Sept. 25, 1998.
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Re: THE DIFFERENCE BETWEEN LIFE AND NON LIFE

Postby BioWizard on September 9th, 2007, 1:10 pm 

lucaspa wrote:
BioWizard wrote:You hit the nail on the head there. Aging is a cellular program, not passive entropic decay of cells, and it was evolved to serve certain functions in multicellular organisms, which may be beyond the scope of this discussion.


Part of aging seems to be a cellular program. That is, differentiated cells are programmed for a certain number of cell divisions before they apoptose and die. It's called "Hayflick's number" after Leonard Hayflick. The number varies from species to species. For humans it is about 50. Data indicates that it is the telomeres and levels of telomerase that provide Hayflick's number.

Some adult stem cells do not seem to obey Hayflick's number. The multipotent adult stem cells that I work with, for instance, have gone over 150 cell doublings and seem fine.

Another part of aging is accumulation of damage due to oxidation of lipids, proteins, and DNA and damage to DNA itself thru methylation and other chemical reactions.

Remember, natural selection is pretty much done with us after we have kids. So the mechanisms to protect cells from oxidative and other damage need only do well enough to get the individual thru having kids that survive to have their own kids. For humans that is about 35-40. After that we are going on momentum.


Yep I know that.

But to go back to what you said, multipotent cells can (under native conditions) undergo an equal number of divisions as differentiated cells without accumulating as much DNA damage or telomere shortening, and thus without apoptosing. This makes me think that it's mostly a cellular program, and that molecular damage and telomere shortening is an outcome or mediator, rather than a cause (although it can be - think feedback amplification), for the phenomenon of cellular aging. Otherwise germ cells would have accumulated damage over generations, bringing the population to a hault (think continuous germline).

lucaspa wrote:
Although interestingly, I saw a report somewhere a few years ago that said something about bacterial division being not 100% symmetrical, and that bacteria can concentrate molecular toxins in one of the daughter cells, and so after some generations, the toxins levels get too high and the daughter that ends up with them dies. They described it as a form of unicellular aging, which of course I don't agree with. I can't confirm the validity of their results either.


Can you at least do a PubMed search and see if you can find the paper? That would help.


I did do a PubMed search, but I couldn't locate the paper. I fuzzily recollect that it was in a summer issue of Science, I think 2003. I'll check in there.

lucaspa wrote:
BioWizard wrote:Incidentally, it's the next book on my readng list. It was suggested to us by the lecturer in a course I'm taking. The course is on mitochondria - everything mitochondria. We can read it together and discuss it in the books forum. That'll have to wait though till I'm done with my proposal and also Lincoln's book.


Do you have any reading in that course on mitochondria replication? I'm finding that very difficult to fine either in PubMed or in books. Thanks.


If we cover that, I'll pass on the references.
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Postby BioWizard on September 9th, 2007, 2:03 pm 

Yep, found the original report in SAGE/KE Science June 25, 2003.

Growing Old, Bacterial Style
Mitch Leslie

http://sageke.sciencemag.org/cgi/conten ... 003/25/ns5
Abstract: Like us, some bacteria age, although scientists long believed they couldn't. Theoretical studies suggest that unequal division is the prerequisite for aging, and a new study of an asymmetrically dividing bacterium backs the argument. Starvation also provokes aging in some bugs, causing them to start producing proteins that are vulnerable to oxidative damage. Deprived bacteria deploy defenses against oxidation that are similar to those in worms and higher organisms. Bacteria's ability to survive brutal conditions might clue scientist in to ways to make our own cells resist aging.

Citation: M. Leslie, Growing Old, Bacterial Style. Sci. SAGE KE 2003, ns5 (25 June 2003)
http://sageke.sciencemag.org/cgi/conten ... 003/25/ns5


Senescence in a Bacterium with Asymmetric Division
Martin Ackermann, Stephen C. Stearns, and Urs Jenal

http://sageke.sciencemag.org/cgi/conten ... 003/25/or8
Abstract: Science 300, 1920 (2003).

Senescence is a deterioration of function with age manifested as a decrease in reproduction and survival. Prokaryotes are considered to be nonsenescent and potentially immortal organisms. In this Brevia, Ackermann et al. show that an asymmetrically dividing bacterium, Caulobacter crescentus, exhibits a decrease in reproductive output with age. This organism may be used as a model system for studies of the fundamental properties of senescence
.

And here's what PubMed turned up:

Some highlights of research on aging with invertebrates, 2006-2007.Partridge L.
Centre for Research on Ageing, University College London, Department of Biology, Darwin Building, Gower Street, London WC1E 6BT, UK.

The invertebrate model organisms continue to be engines of discovery in aging research. Recent work with Drosophila stem cells has thrown light on their human equivalents, and on the role of stem cells and their niches in the decline in fecundity with age. Inspired by observations of aging in bacteria and yeast, a new theoretical study has revealed evolutionary forces that could favour asymmetry in the distribution of damaged cell constituents at division, and hence pave the way for the evolution of aging and selective maintenance of integrity of the germ line. Mechanisms of nutrient sensing and cell signalling in the response of lifespan to dietary restriction have been elucidated. Powerful invertebrate models of human aging-related disease have been produced, and used to start to understand how the aging process acts as a risk factor for disease. In the near future, studies of invertebrate aging are likely to move away from an exclusive reliance on genetic manipulation towards a more biochemical and physiological understanding of these systems.
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the difference between life and non life

Postby MINARAS on September 13th, 2007, 11:25 am 

First of all,i like the idea that fire is a primitive form of life.Second,i think that we must isolate if we are talking about mitochondria,stem cells or the whole body.If we forget all the things that composes a human body i really beleave that a body of a human or an animal is a sum of chemical reactions,and we have to see it only as that,as a whole,and not getting comfused with mitochondria,stem cells etc.Scientists have accepted that life was originated from a single cell,which was the first cell on earth, and composed the first thing that was a form of life. The evolution of this cell had as a result the formation of life the way that we know and see today. A problem with this idea is that, as we know, if we had just a single cell in earth right now, and out of it there was nothing, then not only this would not lead to the formation of more complicated forms of life,but this single cell soon would be dead.Despite of that,most scientists accept the single cell theory.The new theory that we introduced claims tha tit was not necessary to be a first single cell to start the evolutionary process that would lead to life as we know it today, but says that life preexisted , because even a single chemical reaction is a form of life.The creation of the first cell actually is the result of the existence of life.

Lets see now another problem: In the beginning, life on earth was simplier than today. That means that there was a system of chemical reactions that gave its place to a more complicated one.This sounds a bit strange because if a system of chemical reactions does not get energy from outside, leads to an equilibrium state. If we accept that our new theory is true, means that there had to be an external source of energy{probably the large quantities of energy that comes everyday on earth from the light of the sun that lead not only to the survival of the first forms of life, but also to their evolution. Please excuse me for my very bad english!!!
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Re: the difference between life and non life

Postby BioWizard on September 13th, 2007, 2:24 pm 

MINARAS wrote:First of all,i like the idea that fire is a primitive form of life.


That was actually used to demonstrate a misconception about life, so don't get too attached to it. Fire does not satisfy the definition of life, in that it is:

1- strictly exothermic
2- does not carry any inheritence code, and thus cannot evolve. It's a propagating chemical reaction, not a metabolic network of catabolic AND anabolic reactions, whereby the anabolic reactions constitute the self assembly processes of life.

Second,i think that we must isolate if we are talking about mitochondria,stem cells or the whole body.If we forget all the things that composes a human body i really beleave that a body of a human or an animal is a sum of chemical reactions,


Indeed.

and we have to see it only as that,as a whole,and not getting comfused with mitochondria,stem cells etc.


There's no confusion. Mitochondria are ancient bacteria which got incorporated in cells, and coevolved with them for such a long time that they are now functionally inseparable.

Scientists have accepted that life was originated from a single cell,which was the first cell on earth,


Not really. It doesn't have to be the only cell that arised on earth. It is however the one (or one of several closely related) that survived and managed to have descendents lasting till today... hence they're here.

and composed the first thing that was a form of life. The evolution of this cell had as a result the formation of life the way that we know and see today. A problem with this idea is that, as we know, if we had just a single cell in earth right now, and out of it there was nothing, then not only this would not lead to the formation of more complicated forms of life,but this single cell soon would be dead.


No. The cell did not appear out of the blue. It evolved from simpler molecular assemblies which were probably neither unique nor scarce in its environment. And so, the cells which were most successful over others that might have emerged need not be the only ones to have ever existed.

Finally, if you take any component of a cell nowadays and leave it in noncontrolled conditions, it will degrade quickly because:

1- The conditions are different from those which would have allowed such structures to exist stably independently
2- These structures have evolved in the context of the cell to the point where they can no longer exist on their own
3- The world is littered with enzymes from life forms that populate it, and so they will quickly degrade any DNA, RNA, or protein, if they encounter it.

Finally, its not true that if you place a single cell out there it will die. With the absence of parasites and other cells that might cannibalize it, it will probably divide and fill out any niche available to it. That's why waters are infested with single celled organisms.

Despite of that,most scientists accept the single cell theory.The new theory that we introduced claims tha tit was not necessary to be a first single cell to start the evolutionary process that would lead to life as we know it today, but says that life preexisted , because even a single chemical reaction is a form of life.The creation of the first cell actually is the result of the existence of life.


That's a misrepresentation. No one's pushing that there was just one cell that appeared and gave rise to all life.

Lets see now another problem: In the beginning, life on earth was simplier than today. That means that there was a system of chemical reactions that gave its place to a more complicated one.This sounds a bit strange because if a system of chemical reactions does not get energy from outside, leads to an equilibrium state. If we accept that our new theory is true, means that there had to be an external source of energy{probably the large quantities of energy that comes everyday on earth from the light of the sun that lead not only to the survival of the first forms of life, but also to their evolution. Please excuse me for my very bad english!!!


I have no idea what you're talking about.
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The difference between life and non life

Postby MINARAS on October 1st, 2007, 11:41 am 

As we said, living organisms are a summation of chemical reactions.What happens now when they die? There is a disorder in a system of reactions (for example brain necrosis, which means that in a large number of neural cells there is a stop in the reactions that happen there) that lead in a chain reaction way to a disorder in other reactions and then in others and so on.The final result is that there is a necrosis in the whole body, in a chain reaction way.

This means that if somebody with a magic way made all the chemical reactions of the body started working simultaneously,(or else there was an arousal of all the reactions and all were working again),we woud not have the chain reaction leading to death again, but the organism would gain life again.The question is with which way we would stimulate all the reactions simultaneously.This means that the source of this energy, would give the appropriate energy to the whole volume of the dead cell, with the right timing.One idea is the use of an appropriate form of electromagnetic waves.
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Postby dho on October 1st, 2007, 2:41 pm 

Starting the chem reactions would not necessarily restart life since irreversible damage to the system most likely happened during the down time.
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Postby BioWizard on October 1st, 2007, 2:44 pm 

When life ends, reactions don't stop; rather, they reach equilibrium. Meaning, life is not a matter of these reactions simply taking place, but rather a matter of networking them altogether in a way that prevents them from reaching equilibrium. This allows the organism to utilize the released enthalpy (liberated from nonequilibrium reactions) in driving processes with positive free energy. When death occurs, the system gets decoupled and the organism can no longer release sufficient enthalpy to counter entropy, and disorder takes over.
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The difference between life and non life

Postby MINARAS on January 7th, 2008, 1:10 pm 

1)Imagine that with the help of a sourse of light we in a way,some chemical reactions in a small place.After a period of time,they are getting more and more complicated.Lets hypothesize that someday the whole system becomes extremely complicated.We could not see nothing more but a mixture of colours and shapes.This is life.But human is a part of this complicated system which means that he sees thing in a mirror like way,because he is in the system.so it is very difficult for him to see life in an objective way.2)Nature does not promote a certain form of life,but what we see,is the result of the sum of the reactions that happened through history.
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Postby BioWizard on January 7th, 2008, 1:54 pm 

You might want to clean that up (grammatically) and take it to the philosophy section. For the sake of doing science (which is what we do in this section), life has a relatively agreed upon operative definition.
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Postby Removed user on January 7th, 2008, 2:27 pm 

Nature does promote a certain form of life and this is based on the natural laws governing physical systems. All systems have certain basic properties and living systems are no exception.

Life is described by describing the properties of living things. The specific group of properties that are considered inherent to living beings may be considered arbitrary by some but by setting boundaries science is able to do a very good job of gaining understanding within said boundaries. One of the major flaws of non-scientific thought is that it's often unbounded, although on very rare occasions this can be an advantage.

http://en.wikipedia.org/wiki/System
http://en.wikipedia.org/wiki/Life
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The difference between life and non life

Postby MINARAS on March 19th, 2008, 6:15 am 

entropy of life


1)what is the difference between a man that is alive and a man that is dead?In both cases the body is consisted from the same elements and compounds.But in the first case these compounds are reacting with each other and the structure of the body changes every moment.In the second case the chemical reactions of the body are lead to an equillibrium and so the composition of the body remains unchanged.The structure of a dead man cannot change if there are not microorganisms in its environment.

2)The property of reproduction in living beings that are chemical reactions seems to actually be a result of the energy that forces the chemical reactions to continue happening.Life continues because chemical reactions continue.Reproduction seems to be one of the most ancient properties.

3)The relativity of entropy

What happens with the ntropy of living systems that are chemical reactions?The energy that comes externally on earth in the form of light could explain the lowering of entropy.However ,if in the beggining there where 2 or 3 reactions and after a while there are more and more ,and more complicated, seems that the entropy of the whole living system on earth or else nature, is raising.But remember that previously we said that human is not a neutral observer of things, but he is changing together with the system.This confuses him.What impact has that?It means that if humans entropy is raising slower than whole living natures entropy ,he will think that his entropy is lowering.Its something like relativity of motion.One exaple is this :Imagine a large number of birds that are flying one next to other to the same direction.If we tell them to fly one far from the other,so the group will start separating, the entropy of the system will start raising.Imagine also that there are three birds that are very close to each other,somewhere in the group.If they separate with less speed than the others and we consider these 3 birds as a system,the systems entropy will actually lower relatively with the whole system of the birds.
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The difference between life and non life

Postby MINARAS on March 19th, 2008, 6:17 am 

1)living organisms normally are not dying because the chemical reactions that are composing them are continuing happening.if we analyze all these reactions we will have a very good view to their homeostasis.As we said we are seeing the world from the inside , or else in a mirror like direction, because we our selves are part of things, so we appreciate things from its results.We think that homeostasis is a very magical and perfect mechanism, because we are the result of homeostasis, but the theory that we analyzed says that homeostasis simply is the cataloge of the chemical reactions that are still happening, and just because they keep happening, the organism is alive.



2)the complex organic compounds that are composing living creatures probably are the results of many years of reactions, or else they are the fingerprints of the reactions from the beginning of all the reactions till today.



3)because human is a very complicated system of reactions that all depend from each other, its very loggical to say that it is almost impossible to treat compeletely a chronic disease with a single drug.The human body is not a car that we fix the part that is wrong and everything is ok.Instead, its reactions are so complicated, that (unless the illness is caused by a foreign agent e.g. a microbe, or by that lack of a substance that can be replaced), if there is a problem with a reaction this will lead to a chain reaction way problem to other reactions of the body as well.This mechanism is responsible for chronic diseases.The only way to treat compeletely this disease is to put back the initial reaction with the problem the way it was.Every other method will reduse symptoms, but not heal.Or it may theat a problem and create another.A good example for this is the treatment of high blood pressure or cholesterol.This are much more complicated that we though, that ever with the proper treatment of high blood pressure or cholesterol, we are not talking about healing, but for statistically significant improvement.Some studies also shows that there is no decrease in mortality even with the treatment of the risk factors.Another good example are rheumatic diseases.No complete cure exists.Drugs have many side effects.One hole is closed, and another is opened. Even in major diseases there is a big dissosiation between the pathogenetic mechanisms that are discovered and treatments.This diference will continue growing if we dont realize that the mechanism that organism works is more complicated.
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The difference between life and non life

Postby MINARAS on April 30th, 2008, 5:38 pm 

1)lets come now to the position to answer if the spores that some microorganisms forms(e.g. cryptobiosis,anhydrobiosis etc) are living forms.If their metabolism is not zero, if it exists but it cant be detected because it is so weak, then they dont differ in anything from the other organisms.If their metabolism is absolute zero, then the answer gets more complicated.The fact is that it doesnt matter what it is, because the question is useless.Life as we see it is simply the result of the chemical reactions on earth.As we said ,we are part of the system and we dont realize it, but if we were alien forms of life for example, and we were watching the earth from outer space, then we would see only a very complicated network of reactions that are becoming more and more because of the energy of light.This system would have different structural forms, colours, etc.So, what happens with the spores is that because they face very unfriendly conditions ,the certain chemical reactions stop happening or they are lowering their rate.According to our definition, they are not life, but what is life?Life seems to be more an invention of us,or else a term that we use to describe anything that looks like us.There is not such a thing as life, its an illusion.An organism is the reactions that we see, and we think they are something amazing because we see them separately from all the other reactions that are happening in the world.We judge them from their reult, which is that they become like us.We are a part of the reactions that are happening as well, and while we see organisms that look like us, we think they are independent creatures, but actually they cant be separated from the whole soup of reactions.The spores are becoming as they were before because their reactions start happening, and they start looking like us.There is not such a thing as homeostasis.So tthe existence of their reaction gives the illusion that we called life.
2)Another implication of the theory is that because the sum of the chemical reactions is a chain, it means that the cause of a disease maybe come from the organ that has the symptoms, but maybe not.An initial problem causes its irregularity, but depends of the vulnerability of each organ to see in which organ the symptom will be seen, because all the reactions communicate with each other, and when a problem exists its like a volcano and we dont know where will it explode.For example a psychic disorder can cause a problem from the liver for example
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The difference between life and non life

Postby MINARAS on September 27th, 2008, 7:12 am 

continue from previous
Of course, when we are talking about chains of chemical reactions, we do not mean it in the simplistic way, that they are in a chain, and everything is happening in an order, where the formed substance goes to the next position to react with the next substrate etc. Things in nature are much more random, and it is difficult sometimes for us to detect which is the next step.One of the major difficulties are some passive phenomena that happen, such as plasma flow, passive diffusion through membranes because of difference in concentration, or electrical gradients, excretion throught ducts, etc.The latter are phenomena that happen passively ,due to the laws of nature and are not defining life, the way the chemical reactions do. To be more symbolical, they play the role that scientists play in a chemical lab:they transfer the substances from one tube to another, arrarge the conditions, etc.But the chemical reactions are the big difference.

Of course , if these movements that we are talking about were not there, we would not be the way we are.We are the results of all these , and so it is normal to think that if something was not the way it is, WE would not be there, the way we are!So we think that they are essential for us and everything was arranged perfectly, and if something was a bit different ,we would not be there, but as i told everything depends on who is the observer.We are a changing complex, and everything that happens lead to us.We see things from the opposite side though.It is like we are in a moving ship, and so we realize things differentl from someone who is standing in the port.Most of all we dont have a good sence of our own movement.If we were not in the living system, we would not find any reasoning for all the creatures on earth.Even if we were tables for example, we would think that the most perfect creatures are the tables.All depends on what is the observer.
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Re: the difference between life and non life

Postby lucaspa on May 19th, 2009, 9:36 am 

MINARAS wrote:First of all,i like the idea that fire is a primitive form of life.


But fire isn't alive. It lacks anabolism. Anabolism and catabolism together make up metabolism -- one of the characteristics of life. Catabolism is breaking down chemicals for energy. Fire obviously does that well. Anabolism is making more complex chemicals from simpler ones using energy. Fire does not do that.

Second,i think that we must isolate if we are talking about mitochondria,stem cells or the whole body.If we forget all the things that composes a human body i really beleave that a body of a human or an animal is a sum of chemical reactions,and we have to see it only as that,as a whole,and not getting comfused with mitochondria,stem cells etc.


Different chemical reactions happen in different specialized cells and different parts of a cell. That's why you can't view the human body as a simple sum of chemical reactions. The Krebs cycle happens nowhere else in the cell but the mitochondria. Therefore the major production of ATP - absolutely essential for anabolism -- happens in the mitochondria. As another example, calcium and phosphate precipitate to form mineral only in matrix synthesized by either osteoblasts or hypertrophic chondrocytes. If that chemical reaction happened all over the body, our whole bodies would be bone.

A problem with this idea is that, as we know, if we had just a single cell in earth right now, and out of it there was nothing, then not only this would not lead to the formation of more complicated forms of life,but this single cell soon would be dead.


Ah, but an essential characteristic (among the 4) of life is that it reproduces. So, in the situation you described, that cell would not be alive.

The new theory that we introduced claims tha tit was not necessary to be a first single cell to start the evolutionary process that would lead to life as we know it today, but says that life preexisted , because even a single chemical reaction is a form of life.The creation of the first cell actually is the result of the existence of life.


RNA World does indeed state that there were replicative molecules before there was a cell. However, the one way we know to get life from non-life results in a cell first, RNA later.

In the beginning, life on earth was simplier than today.


Not necessarily. That is one startling discovery with the cell-first experiments: the first cells were just as complicated -- perhaps even more complicated -- than modern cells.

This sounds a bit strange because if a system of chemical reactions does not get energy from outside, leads to an equilibrium state. If we accept that our new theory is true, means that there had to be an external source of energy{probably the large quantities of energy that comes everyday on earth from the light of the sun that lead not only to the survival of the first forms of life, but also to their evolution. Please excuse me for my very bad english!!!


As you say, there is the energy of the sun. That drives electrical storms, heating of water, and a number of other secondary sources of energy. The same abiotic chemical reactions that produce amino acids also produce porphyrins. These can be incorporated into the first cell form by thermal heating of amino acid and then hydration. That means that some of the first cells were photosynthetic.
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Re: The difference between life and non life

Postby BioWizard on May 19th, 2009, 12:40 pm 

I can agree with almost all of lucaspa's points and explanations. I just have one comment to add. Cells need not have come before RNA macromolecules. RNA replicators could have appeared long before cells were formed around them, or before cells encorporated RNA into their structures, if you want to consider lipid bilayers as "cells". Remember that organelles like mitochondria themselves originated from cells (alpha-proteobacteria in this case).

Can you please reference the first cell experiment you're talking about?
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Re: The difference between life and non life

Postby MINARAS on October 19th, 2012, 2:39 pm 

In this point, someone would ask:Why are the forms of life the way they are today?In other words, what gave them their shape, and their characteristics?How can simple reactions lead to the complicated forms we see today?The answer is that the forms we see today are the result of what had happened, so we(the results), see ourselves as the most capable to survive, which is true, because thats what happened through time!as we told, virtually we see history from the opposite side, or else ,we see the theory of evolution from the end towards the beggining


p.s. sorry for the delay, but i promise i will answer to everybody specifically soon....
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Re: The difference between life and non life

Postby NeoTheseus on October 19th, 2012, 8:23 pm 

I would love to jump in on this discussion. I was actually thinking along these lines for a few weeks. I have been in medicine, nursing to be exact, for over 20yrs. I am currently in school to be a nurse practitioner. With all of that said, I have a problem with the generally accepted definition of life. I agree with the concept of metabolism and the response to its environment. The issue I have is with the concept that organisms need to be able to reproduce in order to be considered alive.

First, I understand that we, as humans, reproduce cells constantly even if we are not engaged in sexual reproduction. The way I understand organism reproduction is that the organism reproduces, TOTALLY. I will give two three examples how this falls short.
1. Horses when they mate with donkeys produce mules, which are sterile! I believe mules are a form of life even if it can't reproduce.
2. Pets, like Fido the dog, may be spayed or neutered. They are seen as family members by their owners. I think you all would have a hard time convincing this family that because Fido can no longer reproduce that Fido is not alive.
3. Also, let's talk about humans; US! Children cannot reproduce. They are physically immature. Seniors can't reproduce; they are beyond the years of conception. Are we only alive from puberty to menopause? Are we a virus during the other stages of existence?

I feel sentient beings are easier to define compared to other forms of life; they have consciousness. Life ends, for the organism as a complete entity, when consciousness is lost, even subconscious and dream states, and when cognitive brain activity ceases. I know life in this regard can be ethically argued but give or take, that is the border or boundary of life. Other cells may live for a while, bacteria may survive, and the body or its parts may be sustained, but the person as we know them as a living being is gone with the total loss of consciousness.

Other forms of life are more arguable. How can we say a tree is alive but a virus is not; I don't know. When do chemical reactions cease being just chemical reactions & become metabolism? ADP & ATP production perhaps; an internal combustion engine can utilize energy from gasoline. Did the car eat or drink it? It interacts with its environment. If you disagree watch a car interact with a telephone pole. I know that is ridiculous but cars rust as it interacts with the elements.

As I already said, I feel reproduction should not be a criterion to define life. Sentient life is easier to define, but ultimately what life is is very grey. I would love to further discuss this.
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Re: The difference between life and non life

Postby owleye on October 20th, 2012, 2:26 pm 

Neotheseus...

How would you respond to the question of whether viruses are alive?

One problem with venturing into the question you are asking is that it is probably a diversion from the topic. This is to say there is a distinction between on the one hand being alive and being dead and on the other hand life and non life. The latter deals with the question of evolutionary history of life whereas the former merely deals with individual participants in that evolution.

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Re: The difference between life and non life

Postby NeoTheseus on October 20th, 2012, 2:45 pm 

owleye wrote:Neotheseus...

How would you respond to the question of whether viruses are alive?

One problem with venturing into the question you are asking is that it is probably a diversion from the topic. This is to say there is a distinction between on the one hand being alive and being dead and on the other hand life and non life. The latter deals with the question of evolutionary history of life whereas the former merely deals with individual participants in that evolution.

James


I don't know, to answer your question pertaining to are viruses alive. I feel it all hinges on the difference between metabolism & simple inanimate chemical reactions. Also, I don't understand your dichotomy between life/non-life & being alive & being dead. If reproduction is used as a criterion, the mule would be a non-life that is alive. This is preposterous. Something must have life to be alive. It is impossible to be alive & non-life. I posit that mules, children, spayed & neutered animals, the celibate, and old people are alive, until they are not regardless if they can or do reproduce.
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Re: The difference between life and non life

Postby owleye on October 21st, 2012, 3:27 am 

NeoTheseus wrote:
I don't know, to answer your question pertaining to are viruses alive. I feel it all hinges on the difference between metabolism & simple inanimate chemical reactions. Also, I don't understand your dichotomy between life/non-life & being alive & being dead. If reproduction is used as a criterion, the mule would be a non-life that is alive. This is preposterous. Something must have life to be alive. It is impossible to be alive & non-life. I posit that mules, children, spayed & neutered animals, the celibate, and old people are alive, until they are not regardless if they can or do reproduce.


I think you missed the point. Mules are obviously living creatures, having evolved in accordance with principles of evolution. However, that it doesn't self-reproduce doesn't disqualify it from the being part of the category life, even if life itself requires reproduction in order to qualify. It is a category mistake to draw that conclusion. Life is manifold, but at its basis is a renewal of an identity, best grasped by the structure of DNA itself. Overlooking all the control and energy aspects that go into it, the structure of DNA is basically adapted to self-reproduce under the assumption that the nucleotides that form the backbone sequence are plentiful in its environment. It was the first thing noticed by Watson following the discovery of the double helix. Reproduction is the function of DNA. Of course, to avoid being screened out by the environment, controls of various kinds exist to shape the success of this function. Reproduction strategies abound in nature. Bacteria reproduce their DNA abundantly, whereas other species for a variety of reasons, less so. The reason I asked about the life of viruses is that they probably evolved as detritus of bacterial reproduction, and survive because they are parasitic on their host. I'm inclined to think they are life forms, though I suppose I'm taking a larger view of this basic function. Individuals, that is individual cells and organisms, are themselves projections of the DNA that represent the strategic response to their reproductive success. Both cooperation and competition are embedded within that strategy, and there's nothing particularly sacred about whatever the derivation of its success. Mules apparently don't need to self-reproduce to be being considered successful biological creatures.

Notwithstanding this point, humans have a way of interfering with natural selection, one in which instead of the environment playing the role it does in the success of the adaptations to it, human intentions come to play an active role as well. And as I see it, humans intentions seem to be growing in magnitude with each passing era. Mules may therefore owe some of their success to the needs of humans.

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