Discussion: Origin of life.

[mihail]

1st sorry for my english, if there are mistakes...

 

I have an idea in my mind and I would like to ask you people, who understand science more than me, what do you think of it:

 

So we separate living world and non-living world (saying non-living I mean stones, water and so etc.). The living world has one very specific thing in itself. It is, let's call it force that make it survive. In organisms this is called 'an instinct of self-preservation'. What is this force? In my oppinion this is a natural force that existed even before the life(what we understand of it) appeared. If this is so, it means that life is just a manifestation of this force. This force I suggest is something absolutely normal like the force of gravitation and it is one and the same everywhere in the universe. I believe this force, affects both 'living' and 'non-living' worlds. If this is so, it means that life exist in stones and in all nature, because it is element of the universe.

Well it is not the complete exact idea, but I hope I managed to explain it understandable. It sounds possible to me... PLEASE COMMENT, ASK QUESTIONS IF DID NOT UNDERSTAND. Thank you!

[SkepticLance]

Mihael,

Many people have postulated a force of that or similar nature, and that idea is heavily represented in certain alternative therapies. For example : acupuncturists postulate a force they call Chi.

 

However, all those ideas are purely hypothetical. Many scientists have tried to find evidence of such a force, and failed. Most probably, no such force exists.

 

The force you talk of, to drive organisms to survive, is not needed. Normal ideas of evolution are sufficient to explain the behaviour of animals that increase chances of survival. Quite simply, if any animal has genes causing behaviour in a way to make it less likely to survive, it is less likely to pass on those genes. Over time, those genes will be weeded out of the population.

 

Animals whose genes alter behaviour in ways that increase chances of survival will likely survive, and those genes will become more frequent in the population. No force is needed.

[Daecon]

You mean like an energy that's present in self-replicating complex molecules?

 

Whatever it is that differentiates living matter from dead/inert matter when biochemically they're exactly the same?

 

It must be more than just ordinary electricity, mustn't it?

[thedarkshade]

The living world has one very specific thing in itself. It is, let's call it force that make it survive. In organisms this is called 'an instinct of self-preservation'. What is this force? In my oppinion this is a natural force that existed even before the life(what we understand of it) appeared. If this is so, it means that life is just a manifestation of this force. This force I suggest is something absolutely normal like the force of gravitation and it is one and the same everywhere in the universe. I believe this force, affects both 'living' and 'non-living' worlds. If this is so, it means that life exist in stones and in all nature, because it is element of the universe.

Well it is not the complete exact idea, but I hope I managed to explain it understandable. It sounds possible to me... PLEASE COMMENT, ASK QUESTIONS IF DID NOT UNDERSTAND. Thank you!

That sounds like a 5th fundamental force:eek:... but there is nothing which would support what you say, right? This "force" reminds me of "vis vitalis", a "force" or ability which was thought was the reason that organisms make organic substances.

 

It is certain that all the life today is as a result of that single cell that was the first thing to live. How that was "created"? Well, we have Miller's experiment which is a sort of scientific back up. But I'm sure there is something a lot lot more complicated behind that. The origin of life is indeed an interesting issue.

 

But shouldn't threads like this be on speculation sector?

[mihail]

ok you say, the life does not need this 'force'. Let's go back to the time when there had no life. How come does the life begin it's exitance? I understand that it went a lot of time for this to happen. I just cannot understand, how come there appears life from nothing. The stone and water we believe are static and do not change only if some force from outside is involved. And you mean that it started to happen accidentally and it just continued to develop under to its own momentum? I cannot comprehend this... really! please explain.

 

sorry for the english, stupid me!

[ecoli]

Don't think of it as an accident. Think of it as a specific set of conditions that are very rare. But, even if the conditions are rare, on a long enough time line, a set of molecules just happens to be at the right place at the right time for the right set of reactions to occur.

 

Now this 'force' you speak of. It might help to think of it this way:

 

Molecules are not conscious, so obviously the idea that a molecule would 'want' to replicate itself is absurb. Molecules don't really want anything.

 

But, imagine that, by random chance, there was a molecule that somehow was able to replicate itself. The code that controls the molecules ability to replicate itself is contained within that molecule. Therefore, all replicates of that molecule will also contain the ability to replicate themselves.

 

Now, imagine, again by chance, one of those replicates lost the ability or the 'desire' to replicate itself, by some internal change in that molecule. Because that molecule does not replicate itself, no other molecules will contain that design information, unless there is another random change.

 

Meanwhile, molecules that DO contain information for self replication will continue to replicate. Molecules that do not will eventually break down, and their information encoded within is lost.

 

As you see, only molecules that contain information to replicate persist.

 

The force you speak of comes not as a result of some inherent natural force that makes molecules that 'want' to replicate. It's just that molecules that, by random chance develop the ability to replicate will out-persist molecules without this information.

 

Therefore nature favors the proliferation of molecules that contain the information to proliferate, simply because it is the molecules that are ABLE to proliferate that are the ones that hang around.

 

Evolution of species comes out of this, where molecules that can replicate better outperform ones that don't. These molecules, by random chance, find that they can associate with other molecules that can help them replicate even better, and the first cells are built.

 

Do you understand now?

[thedarkshade]

You got a point. I mean, the creation of everythingness from nothingness simply violates logic. The same goes for the Big Bang.

 

How did life appear is a big question. So far there is no CLEAR view for how did it exactly being, though there is this experiment! If you stop for a second, think of the life that stand everywhere around you and ask how did all this appear, then you really realize how less we know about the nature. How small are to understand this world, and tend to understand the infinite universe. It just is absolutely exciting to think of stuff like this. I mean, you think of how life showed up, you make your own picture of it, think of it in the way you want and so might do everyone. That's because there is yet nothing that would decisively say "This is how life appeared. It started exactly this way and if circumstances somehow manage to come like this again, life would again begin."

 

And I have no problems understanding your english. I'm not a native speaker either

 

edit: BTW ecoli, this somehow word really does not fit pure science. Science is about how and why!

[mihail]

Thank you very much for the serious answers. I tried to discuss this in one non science forum and I met only the jokes of the people there. Well, I know one thing for sure now and it is that I need to read a lot more before I start making any conclusiuns for things like that. Thank you people!

[ecoli]

Thank you very much for the serious answers. I tried to discuss this in one non science forum and I met only the jokes of the people there. Well, I know one thing for sure now and it is that I need to read a lot more before I start making any conclusiuns for things like that. Thank you people!

 

Welcome to SFN... where the men are real men, the women are real women are where we always take our science seriously.

[thedarkshade]

OMG ecoli, you could at least have chosen a better statement!

[ecoli]

OMG ecoli, you could at least have chosen a better statement!

eh, give me a break, I've been studying biochemistry for the last 5 days. I'm tired!

[Drallig9399]

You got a point. I mean, the creation of everythingness from nothingness simply violates logic. The same goes for the Big Bang.

 

How did life appear is a big question. So far there is no CLEAR view for how did it exactly being, though there is this experiment! If you stop for a second, think of the life that stand everywhere around you and ask how did all this appear, then you really realize how less we know about the nature. How small are to understand this world, and tend to understand the infinite universe. It just is absolutely exciting to think of stuff like this. I mean, you think of how life showed up, you make your own picture of it, think of it in the way you want and so might do everyone. That's because there is yet nothing that would decisively say "This is how life appeared. It started exactly this way and if circumstances somehow manage to come like this again, life would again begin."

 

And I have no problems understanding your english. I'm not a native speaker either

 

edit: BTW ecoli, this somehow word really does not fit pure science. Science is about how and why!

 

This is actually why I came to this board. I just dont understand how life begins from inanimate objects. It seems to defy the laws of physics.

 

If there was no life in the beginning how can there be life now? I'm not looking to judge, I was just wondering if there was a scientific theory to explain it.

[Phi for All]

This is actually why I came to this board. I just dont understand how life begins from inanimate objects. It seems to defy the laws of physics.

 

If there was no life in the beginning how can there be life now? I'm not looking to judge, I was just wondering if there was a scientific theory to explain it.

It's called abiogenesis and it is based on the idea that everything in the universe started from simple structures that became complex over time. Whether these simple structures were influenced by organic molecules or created them in the process is still subject to speculation.

[Drallig9399]

Thanks for the info. I'm reading the articles, although I gotta admit they are way above my head

[Phi for All]

Keep in mind that Earth started as a chunk of molten rock. Much of what came about later was added, like a Universe Soup. Where do you think we got water from if the planet was once too hot for it?

[SkepticLance]

There is no single scientific theory to explain the origin of life. There are, however, a number of results from scientific studies which each give a possible clue.

 

Millers experiments, plus many similar follow up experiments, showed that, in a reducing atmosphere such as the Earth had over its first billion odd years, any major energy source (lightning, ultra violet, meteor strike etc) can induce the gases to react together to create a wide range of organic molecules. This includes amino acids, purines, sugars, fatty acids etc. All the basic building blocks of life.

 

In a world where there are pools of water, these building blocks will dissolve, and eventually make a fairly strong organic solution - the primordial soup. Further experiments show that, on the surfaces of some minerals such as Montmorillonite, and calcite, some of those molecules line up. Once aligned, they can combine to form small polymers, which are essential to life.

 

The existence of certain other chemicals (fatty acids and detergent type molecules) permit the formation of small 'cells' which enclose portions of the primordial soup, presumably including the polymers.

 

If one of those polymers has the ability to replicate (eg a small version of RNA), then it will grow in number and occupy a large part of the brew. If it 'mutates' into different forms, then those different forms will compete with each other for resources, and evolution has begun.

 

Now for the disclaimer. The above is NOT a unified theory of abiogenesis. It is a collection of scientific results and some speculation. The origin of life is still not really understood, and a lot more work needs to be done.

[foodchain]

This is actually why I came to this board. I just dont understand how life begins from inanimate objects. It seems to defy the laws of physics.

 

If there was no life in the beginning how can there be life now? I'm not looking to judge, I was just wondering if there was a scientific theory to explain it.

 

Yuck city, that’s classical physics really. Quantum Darwinism is a neat way to look at it I would suggest. Basically in such isolation or isolated systems do not exist really, not in time at least. The rate of interaction among quantum systems or the smallest aspect of reality is constant and copious. In which you have for lack of better words I would guess constant interference, coherence, and decoherence going on really in some form or another.

 

Also I would suggest from the reality that probability exists in the real world as a facet of physical reality, see role of the dice, that such by itself physically provides more of enough for a basis to allow such to exist by physics. Its just most people do not think of QM in regards to physics for such I think and I do not know why. This I think is a product of the frozen and deterministic mindset brought on by classical physics, such also for the most part generated determinism. As far as I know the reality of QM, which empirically is totally sound so far in regards to physical tests basically denies that reality is either only or purely classical nor is it purely deterministic in some linear sense.

 

I mean for instance you happen to be of matter and energy just like everything else physically at a highly reduced notion of what is physical. This means just like a bouncing ball you happen to be governed by such "laws" even if they are currently temporary and flawed. How do you think a mind could work? How does a c-h bond understand what a Twinkie is? These questions and related happen to blow peoples minds as they do mine but really I think most of it boils down to QM even if our current understanding of such does not match the exact reality of it even if it has one. More and more I am beginning to think its just a constant evolution of stuff, in which produces anything, be it laws of physics, to time, to microbes to the current form of the universe. I have no real way to test this but none the less to answer your original position physics does not outlaw in any way organic evolution.

[Taq_is_hot]

ok you say, the life does not need this 'force'. Let's go back to the time when there had no life. How come does the life begin it's exitance? I understand that it went a lot of time for this to happen. I just cannot understand, how come there appears life from nothing. The stone and water we believe are static and do not change only if some force from outside is involved. And you mean that it started to happen accidentally and it just continued to develop under to its own momentum? I cannot comprehend this... really! please explain.

 

sorry for the english, stupid me!

 

Hello mihail! It is nice to see someone so interested in this subject! I think it is fascinating! But where really do you draw the line for "life"? Don't mind me, I'm just thinking out loud here...

 

All life really is, is a label. Biological life has specific properties it must have to be labeled as "life". But is it really logical to cut off biotic from abiotic at a certain point? If you say all life must have cells, must grow and mature etc etc...then what about the qualities biotic things have that abiotic ones do too?

 

So, let's take a look at the similarities. All life, we can say, is a large system composed of smaller systems, but everything has a system. All "life" is born, matures and then eventually dies. All "life" uses energy from something to function. It functions, then something disrupts the system and it dies. Take a look at abiotic things now. Let's look at a storm. It is born, it uses energy from something, it functions, then it dies. This is true for many abiotic systems. Where do you draw the line as to what is "life"?

 

Also, think of humans. We all have an ability to think and reason. We have nervous systems that can detect external stimuli. When something goes wrong with us interally, we feel pain. That is our signal. What about machines and computers? There are plenty of examples of macines that can detect light or sound. Some computers and robots can think. Technically, we install immune systems into our computers to detect viruses. In other words, machines have the ability to detect when something is wrong with them...just like humans. We don't like to think these things are alive...but where do you draw the line?

 

Could you label an atom as "alive"? Again, where do you draw the line? Our bodies are systems of organs. Each organ is a system of cells. Each cell is a system of organelles, which are systems of molecules which are systems of atoms which are systems of subatomic particles and so on. Is my life my body? Or is my life a system of lives of cells? My city is a system of humans. Is my city "alive"? Well, my city is no different than my body! They are both systems of organization. They function...so where do you draw the line? How can't we say that our bodies are a "city" of cells?

 

Then, we have single celled creatures and multi celled ones. What about a colony of bacteria? They are all alike because they all multiplied from a singe one. Just like my cells did. They all have the same DNA. The only difference between them and me is that my DNA says to create a whole syste of different types of cells where theirs says to just keep making the same thing. But am I one being, or many? Is one strain of bacteia one being or many?

 

Spem and egg...Is the human alive ONLY after the egg is fertilized? Then what? The little sperm that fertilizes it has no life? Where do you draw the line?

 

There is no answer. It is just your own perception.

 

So when we say life spawned from whatever whatever, what are we talking about? "Life" is just an extention of the organization of systems in this universe! We are the newest and most complex systems that nature has evolved us to be and all we are doing is labeling ourselves as a specific "group" that really is just a small part of all existance. There is no definite dividing line.

[tanman636]

http://en.wikipedia.org/wiki/Panspermia

 

This is what i believe.

[lucaspa]

ok you say, the life does not need this 'force'. Let's go back to the time when there had no life. How come does the life begin it's exitance? I understand that it went a lot of time for this to happen. I just cannot understand, how come there appears life from nothing. :

 

Life doesn't appear from "nothing". Life on this planet is a set of chemical reactions. The sum of those chemical reactions (including the reaction of some molecules with each other and water to give a membrane) is life. This is what biochemistry is all about: studying the chemistry of living organisms. So far, we haven't found anything that is not covered by chemistry.

 

As to how to get life from non-living chemicals, there are several possible ways to do this. The one I like best is "protein first". Heat a mixture of amino acids to have them form proteins. The proteins will then spontaneously form cells. The cells are alive. You can do this dry (as in a tidal pool) or at underwater hydrothermal vents.

 

http://www.siu.edu/~protocell/

http://www.theharbinger.org/articles/rel_sci/fox.html

 

So, let's take a look at the similarities. All life, we can say, is a large system composed of smaller systems, but everything has a system. All "life" is born, matures and then eventually dies. All "life" uses energy from something to function. It functions, then something disrupts the system and it dies. Take a look at abiotic things now. Let's look at a storm. It is born, it uses energy from something, it functions, then it dies. This is true for many abiotic systems. Where do you draw the line as to what is "life"?

 

This is where the all four of the characteristics come in. Storms do respond to stimuli (winds), and grow. However, they don't reproduce and they don't anabolize.

 

Fire is another good example. Fires grow, respond to stimuli, reproduce, but they have only half the requirements of metabolism. Fires metabolize, but they don't anabolize.

 

Spem and egg...Is the human alive ONLY after the egg is fertilized? Then what? The little sperm that fertilizes it has no life? Where do you draw the line?

 

This is different. Once again, we are talking ethics and legality, not biology. When you say "human alive" you mean: when do we give the organism the rights and priviledges we have decided go to other members of our species? This isn't a biological question. It is often deliberately confused with biology so that a particular ethical/legal stance can be disguised as science, but that doesn't make it biology.

[Realitycheck]

http://en.wikipedia.org/wiki/Panspermia

 

This is what i believe.

 

There is no reason for it to happen somewhere else before it happens here. The earth is about a good a place for it to happen as anywhere that you look within the next 100 billion solar systems. What this proposes is that all of these building blocks of life somehow composed themselves independently within the frigid recesses or hot furnaces of space. Chemicals typically don't organize themselve in such a complicated manner in these types of environments. It's a really complicated process.

[pioneer]

One way to deduce the life force can be done with simple observations. I am not saying there is a new force, but just an old one being used in a slightly different way. If we look at inanimate matter, in an oxygen atmosphere, it gets oxidized to lowest energy state, end of story. But with life, although oxygen is busy at work, life is able to gain or maintain energy. It does this by storing energy as reduced materials. The fertilized ovum will become an adult person someday, gaining potential energy over time. Life has something about it that allows it to get the better of oxygen and make the process go in reverse, storing energy and passing this on.

 

The most likely culprit is hydrogen, since it is hydrogen that ends up gaining the electron density that normally goes to oxygen. One way to understand this is to look at H2. This is the most stable state of hydrogen. It is so stable, it has the lowest melting point of any compound in nature. If hydrogen was the only atom in the universe, H2 is its lowest energy state, since it has little affinity for other H, except close to absolute zero. If we add oxygen to the picture, the H2 state of hydrogen becomes a high energy state relative to the oxygen-hydrogen system. Life reflect H trying to head to its own native low energy state. But being among oxygen it is being pulled the way, toward H2O. The compromise is C-H and N-H.

 

Let me explain this better with an analogy. Say we have two young brothers and only one toy. We have big brother O and little brother H. Based on this two brother system, big brother will get the toy most of the time. Although this situation has the lowest system energy (big brother is not going ballistic) , it does not imply that little brother is happy with this arrangement. Little brother would like more play time but is prevented by big brother. So he has to get creative to get the toy away from O.

 

If we do an atom count of a cell and assume 90% water, the hydrogen makes up 60-65% of all the atoms. It gets 60% just from H2O. What little brother lacks in size, it makes up with shear numbers. In water H doesn't even have to stay put but can migrate from O to O looking for happier hunting grounds.

 

When cells divide the metabolism reaches its highest levels, or O gets really dominant over the H. The daughter cells build back up the H side of the potential, until there is critical mass for O to get the upper hand. Neurons are unusual in that they don't divide after a certain early age. What this means is that O's traditional cell cycle Mardi Gras has been truncated. What that means is hydrogen has gotten the hand and dominates the brain.

 

Evolution is the story of little brother H becoming better and better at getting the upper hand over big brother O. Better than in water. But O doesn't take this lying down, but is resisting constantly. If you look at cancer, this is O domination, due to extreme metabolism. It can also lead to the destruction of the body so O can finish the job permanently.

[iNow]

Shouldn't one first demonstrate the existence of a "life force" before they waste a whole lot of time and energy trying to describe it and where it comes from?

[lucaspa]

http://en.wikipedia.org/wiki/Panspermia

 

This is what i believe.

 

That only pushes the problem elsewhere. How did life arise in the universe from non-life?

 

One way to deduce the life force can be done with simple observations. I am not saying there is a new force, but just an old one being used in a slightly different way. If we look at inanimate matter, in an oxygen atmosphere, it gets oxidized to lowest energy state, end of story. But with life, although oxygen is busy at work, life is able to gain or maintain energy. It does this by storing energy as reduced materials. The fertilized ovum will become an adult person someday, gaining potential energy over time. Life has something about it that allows it to get the better of oxygen and make the process go in reverse, storing energy and passing this on.

 

Pioneer, please don't take this wrong, but please read a bit about biochemistry and, particularly, the Krebs cycle and the electron transport chain. You are trying to re-invent the wheel but you are making a square wheel, not a round one. Look instead at what is already known. Yes, a proton (hydrogen) is involved, but it is as part of the molecule nicotinamide adenine dinucleotide (NAD). Thus the proton is transferred to oxygen to make water. BUT, this process is coupled to the chemical reaction of combining adenine diphosphate (ADP) to adenine triphosphate (ATP). The terminal phosphate bond is the one used to "store energy" and is used in other anabolic reactions thruout the cell.

http://library.thinkquest.org/C004535/aerobic_respiration.html

 

 

If we do an atom count of a cell and assume 90% water, the hydrogen makes up 60-65% of all the atoms. It gets 60% just from H2O. What little brother lacks in size, it makes up with shear numbers. In water H doesn't even have to stay put but can migrate from O to O looking for happier hunting grounds.

 

That doesn't happen. The H-O bond is quite stable. Look at how much energy you must pump in via electricity to split a water molecule to hydrogen and oxygen! You are correct that the electrons in that bond spend more time around the oxygen nucleus than around the hydrogen proton. This gives that proton a partial + charge, since the negative electron isn't always there. The oxygen gets a partial - charge. What this means is that the H of one water molecule tends to "bond" with the oxygen of another water molecule. These "hydrogen bonds" do form and break many times a second. They are what gives water its unique properties as a liquid. The energy of a hydrogen bond is about 4.5 kcal/mole compared to 110 kcal/mole for the H-O bond.

 

When cells divide the metabolism reaches its highest levels,

 

Usually, no. In most cells metabolism reaches the highest levels when the cells are synthesizing extracellular matrix or doing its job. For instance, in osteoblasts metabolism is maximum when the osteoblast is making bone matrix. In liver, metabolism is highest when hepatocytes are making albumin or detoxifying chemicals.

 

Evolution is the story of little brother H becoming better and better at getting the upper hand over big brother O.

 

It can't be. Evolution is about populations of individual organisms changing due to descent with modification. You are talking about what happens within individual cells.

 

It's a nice little fantasy you have about H fighting O, but it has no connection to reality.

[thedarkshade]

That only pushes the problem elsewhere. How did life arise in the universe from non-life?

It does? Not really, the title of the thread is "Origin of life" and panspermia is just another hypotheses related to the subject. It says that life in earth was transfered from some extraterrestrial source and the other stuff that says the link.