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this is my first time here, so go easy on me! I've been trying to find out more about the actual process of DNA replication. Specifically, I am wondering if, when the DNA replicates during cellular division, the result is the original DNA strand and a copy? Or is the original strand destroyed in the process and there are 2 child copies that are identical (aside from mutations) to the original?

I am pretty confident in the end-result, but maybe whoever answers can verify this for me too. My understanding is that the original cell itself is destroyed in the end, but the daughter cells are constructed from the substance of the parent's cell. The initial question will help clarify this process for me too, because I am curious if one of the two daughter cells has the literal DNA from the original, or if basically the entire original cell "dies" in the process and the two new cells are completely new.

Update (to demonstrate research effort):

I have learned how a helicase enzyme untwists the DNA and severs the hydrogen bonds between the nucleotide bases, then single-strand binding proteins bind DNA polymerase to the ends of the strand and begin molding, creating a complimentary strand for each side. It seems evident that half of the "original" is found in each daughter, and the DNA polymerase forms the other half. So, the original is still present, but not in its original form, which is why I'm not sure what the "official" diagnosis is. Is it a parent-child, or two children?

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  • $\begingroup$ "It seems evident that half of the "original" is found in each daughter, and the DNA polymerase forms the other half." - Thanks for doing some self-research: looks like you found your answer! It's okay to write up an answer to your own question. However you still ask: "Is it a parent-child, or two children?" - as the answer you found shows, the answer as far as the DNA molecule itself is neither. $\endgroup$ – Bryan Krause Jul 9 at 19:05
  • $\begingroup$ Thanks Bryan. I think the answer I'm looking for lies a little deeper, but maybe I don't know how to word it. Read my reply to Alex Reynolds' response and see if that helps you understand what I am asking. It may be that we don't actually know the answer yet, but maybe somebody that understands this deeper than I do can enlighten me. $\endgroup$ – Jonathan Plumb Jul 9 at 23:08
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Via: https://en.wikipedia.org/wiki/Semiconservative_replication

Semiconservative replication describes the mechanism of DNA replication in all known cells. It derives its name from the fact that it produces two copies of the original DNA molecule, each of which contains one of original strand, and one newly-synthesized strand. (emph. added)

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  • $\begingroup$ Thanks for the feedback. I suppose my question can be tailored more. A cell's nucleus is considered to be its brain-center. In all living things, there is a controlling consciousness (like our own consciousness that controls our body as a whole). If the DNA is the code that determines cell function and operation, then is the DNA the consciousness? If so, when the DNA splits, what happens to that original consciousness? Does it take up residence in one of the two, newly-formed strands, or is the original destroyed and two "newborns" are produced? $\endgroup$ – Jonathan Plumb Jul 9 at 23:06
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    $\begingroup$ "In all living things, there is a controlling consciousness" including at the level of a cell is not a statement that is supported by any scientific research that I am aware of. Besides some religious perspective (that seems to run into a problem here), there is nothing "controlling" a cell, rather a cell is made of molecules (some of them quite complicated) that respond and interact with their local chemistry. Clearly in DNA replication, as Alex's answer mentions, the DNA molecule in each of the two cells after division is half new and half from the parent. $\endgroup$ – Bryan Krause Jul 9 at 23:13
  • $\begingroup$ I see. Thanks for clarifying all this. It has helped me tremendously! $\endgroup$ – Jonathan Plumb Jul 9 at 23:56
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    $\begingroup$ I'm afraid I don't know what "consciousness" means in this context. Cells are just bags of chemicals where reactions take place. DNA is just a molecule. If the right parts of it are accessible to protein-making machinery and energy (ATP), then life happens. Unless there are errors in replication or cell division that change a copy, one copy of a DNA molecule has the same chemical properties and utility as another copy, all else the same. $\endgroup$ – Alex Reynolds Jul 10 at 1:13

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