Discussion of all aspects of biological molecules, biochemical processes and laboratory procedures in the field.
The genetic material of most living organisms, which is a major constituent of the chromosomes within the cell nucleus and plays a central role in the determination of hereditary characteristics by controlling protein synthesis in cells. DNA is a nucleic acid composed of two chains of nucleotides in which the sugar is deoxyribose and the bases are adenine, cytosine, guanine, and thymine (compare RNA). The two chains are wound round each other and linked together by hydrogen bonds between specific complementary bases to form a spiral ladder-shaped molecule.
When the cell divides, its DNA also replicates in such a way that each of the two daughter molecules is identical to the parent molecule. The hydrogen bonds between the complementary bases on the two strands of the parent molecule break and the strands unwind. Using as building bricks nucleotides present in the nucleus, each strand directs the synthesis of a new one complementary to itself. Replication is initiated, controlled, and stopped by means of polymerase enzymes.
How DNA is Non-living thing?
1- DNA is chemical compound composed of chain of peptides and proteins strung together in a double helix formation that is like a blueprint in telling the organic chemistry in your body how to build cells, what kind of cells, and where to build them. And chemical compounds can not be considered as a living things, because in realty, all chemical compounds ( e.g enzymes, fats , lipids , proteins , ........... etc ) are non-living things. So, if we said DNA is living, we to say that all chemical compounds are living also.
2- DNA is non-living, because it is a molecule not an organism, and this molecule is not sharing organisms in any property, even in replication process as it needs co-workers ( e.g. Enzymes, RNA co-factors ) to succeed its replication.
3- DNA is non-living because it cannot maintain homeostasis on its own. And it does not have a metabolism of its own.
4- Is water living or non-living? Water is the simplest example of something not living but responsible for maintaining life. So, DNA is not living but responsible for so many important functions related to life as it is the genetic material which control all the vital processes in the bodies of -almost all the organisms.
5- DNA is non-living because it is not having any growth and it can't grow, and the process of replication is not growth, it is simply " Duplication ".
6- Firstly, living things are made up of the living material or the protoplasm while non-living things are made up of dead material. And DNA is non-living because it is made up of dead material ( e.g Codons and nucleotides ), in additional to that all the structure of DNA composed of dead materials that are chemical components.
7- If we defined growth as adding new material to our bodies, then DNA is living, because in the process of replication it add new sequences to its structure, but even in this case we have say it is non-living because DNA is not showing development which is the second part of growth, and simply development is the changes in structure living things undergo as it grow and age. So. no change in the structure occurring after replication process.
8- Birth and death is one of the characteristics of living thing, DNA appeared in the living and it is not having birth point to have death point. So, DNA is non-living because it never dies.
9- DNA is not living. It is a chemical - a large fragile molecule - in fact it is a FANTASTICALLY HUGE MOLECULE and for what it is, it is in fact remarkably robust. It contains a series of chemical bonds linked together in a chain, and since not all the links of the chain are the same, it is possible to store information there. Our modern computers use binary - a code made of two digits - 1 and 0 or ON and OFF or MAGNETIZED and NOT MAGNETIZED. DNA uses quaternary code - 4 digits represented by four proteins.
10- It is non-living; there is no debate in the biological community about this. It is a relatively inert chemical that can now be synthetically made. Considering DNA as living is like considering protein to be living. DNA is part of a living cell, as are proteins, fats and a number of other organic molecules.
How DNA is living thing?
The only one proof to say DNA is living, just by the process of replication, because that process sometime refers to making new generation of DNA, and that is just like living thing do.
In additional to the process of replication, DNA is responsible for a huge function, it carries and shifts hereditary information and characters from the parents to the offsprings, and that must be done by living thing.
DNA is not living thing, but it is essential part to all the living things. Without DNA the presence of life could not be. It is non-living as it carries the properties of non-living things most than carrying that of living things.
"Research is what I'm doing when I don't know what I'm doing"
Wernher Von Braun
Thats a great explanation.Thanks Hashem sir.I will be in touch with you.
I found your article very interesting but I have one question. If DNA is non-living why doesn't it continue to function after the body is dead?
I have had time to digest what you have written. I find it hard to accept your justification of DNA as non-living when the majority of its functions are those of a living organism. I have replied to each of your points:
1. DNA communicates with cells giving instructions. How many other chemical compounds give instructions? Don’t most just react?
2. Non-living molecules are those for tables, chairs and sofas. Isn’t DNA a molecule that contains life and therefore is a living molecule?
3. If the DNA is not responsible for homeostasis in a living organism, what is? Doesn’t the metabolism of a living organism depend on its DNA?
4. Why is DNA classified as non-living when it is responsible for so many important functions relating to life?
5. Doesn’t this conflict with #1. DNA communicates with cells giving instructions therefore it cannot be just a simple duplication or replication.
6. If DNA is made up of dead material what gives it life to do what it does? If it is dead why doesn’t it continue functioning after the body dies?
7. If what you say is true then all the changes and growth a living organism goes through from birth to old age is contained in its DNA. It must be a living thing.
8. This is very confusing; a child’s DNA is created and comes into being at the point of conception. At the point of death, like the body only the non-living DNA is left therefore DNA is a living thing.
9. I understand this but what makes the DNA function? Is it a life force? Do you think the answer lies outside the physical?
10. Perhaps it is time to open the debate again. As you mentioned, DNA is responsible for a huge number of functions, functions that must be done by a living thing.
If DNA proved to be living as the huge range of functions you have mentioned would favour, would this change the way we look at life?
A simpleton seeking the truth.
Apart from the utter stupidity of the original question and the easy answer [define life properly (The wikipedia definition is OK) and see if DNA does or not fit the definition. (Hint: the answer is no)] I wanted to point out some flaws in the above post:
1- All hormones, many organic and inorganic compounds and physical phenomena are triggering reactions in cells. Does that make them special?
2- There are no living or non living molecules. A table and a chair can be made of something living (not very convenient in the long term maybe, but definitely possible) or that once was (wood, plastic, wool and many fibers etc...) living, and that has no impact on the fact that they are alive or not.
3- Many other molecules and pumps are directly maintaining homeostasis. And much more directly than DNA. The metabolism of many cells depends on the presence of organic molecules, are they alive too?
4- See above. replace DNA by carbon or water (as in the original post) and reread your question. it is still perfectly factually correct and yet as stupid. Go back to the definition of life that you should have looked at in #1.
5- The OP is wrong, and so are you. The point is that DNA replication is not autonomous. DNA in itself is not enough to create a self replicating entity. Giving instructions is irrelevant. other wise a CD-Rom or my flashdrive could be alive.
6- The OP is wrong, and so are you. There is no difference at the molecular level between what is alive or not. Carbon is carbon whether you find it in Diamond or a piece of DNA. There is no special vital force required to make things living.
7- The fact that DNA codes for what an organism will develop in does not mean anything more than that. It is a blueprint, and without what is around (a living cell, organism) it is absolutely not more alive than a its sequence on a piece of paper (or more likely in a computer file).
8- The DNA is made in the parents before the conception of the offspring. And the reproductive cells are alive (at least for a few days depending on the species) on their own. The DNA does not substantially change after death. it is the same DNA. The cells will slowly decay as they start having problem to find oxygen and nutrients, but some cells are still alive after the body is dead (cf. transplant, cell culture etc..)
9- The OP was right. The DNA is used in living organisms because it is there and life evolved from something that was using DNA. Other molecules could replace DNA as well. No life force necessary.
10- There is no debate, just a lack of understanding of the definition of life. Many atoms and molecules are essential to life, but that does not make them "alive".
But once again then again what would you expect that the fact that DNA was deemed alive would change to our understanding of life? This is just a friggin' label that is quite convenient to communicate, but with little operative relevance.
Science has proof without any certainty. Creationists have certainty without
any proof. (Ashley Montague)
Hi Patrick, I loved your quote; I now have it on my wall.
I have looked at Wikipedia. I accept my original question was rather naive; I accept my reference to living and non-living objects was amateurish; and I accept your comments. In fact I learnt a lot from what you posted.
A couple of points I’d like to open for debate:
As you mentioned DNA is first formed in the individual parent as a single strand. It sends no signals, is not self-sustaining. The majority of this is discarded.
Things change at the point of conception. The two single strands bond into the familiar double helix form. Suddenly the DNA starts signalling, is self-sustaining, replicates, grows and begins to draw sustenance from its surroundings.
(Perhaps a little bit like your CD-Rom when the computer fires it up. This makes your last question about my expectations an interesting concept.)
These functions cease at death. The body cells begin to decay. Although the DNA looks the same (as you posted) it is now dead ‘its functions have ceased’.
As I mentioned in my original post from conception until death DNA follows the pattern of a living organism.
Life (cf. biota) is a characteristic that distinguishes objects that have signalling and self-sustaining processes (biology) from those that do not, either because such functions have ceased (death), or else because they lack such functions and are classified as inanimate.
I think it was Richard Dawkins in his book ‘The Blind Watchmaker’ who speculated that the computer chip might be the next DNA; hope for your CD-Rom yet.
Peter, a simpleton seeking the truth.
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