I don’t get your point. Germ line cells are a variety of stem cell. Soma gets all sorts of phenotypic modifications.
Why not? Most of evolution is neutral. Would you claim that it isn’t really evolution? And no, it can’t be both. Traits can easily be heritable without being subject to selection.
It persists because information required to replenish it after it degrades survives in the sequences of DNA. Without DNA as that information store, that cell or organism perishes.
Seriously? Cellular organization is governed by proteins and RNA, both of whom must be synthesized by interpreting information preserved in DNA. That information is encoded in DNA and persists relatively unchanged through generations.
It is. John we shouldn’t be disagreeing here. When I say DNA holds all the information needed to build organisms, I means that in the same way an updated English dictionary holds all the information (words and their meanings) needed to construct every possible sentence in English. You are human, so you need hemoglobin, cytochrome oxidase, catalase and a vast number of biomolecules to properly function. DNA is comprised of nucleotide sequences which encode information that specifies the production of each of these proteins (and RNAs as well). The same applies to every protein and RNA molecule present in our cells. Since proteins and RNA direct the synthesis, maintenance and elimination of themselves and other biomolecules, DNA indirectly encodes information that specify these processes.
That is what I really mean John. Nothing more, nothing less.
I don’t deny this. I am only saying the information in DNA is what specifies the unique features of whatever organism possesses it, DNA and only DNA holds such information.
Again I don’t deny this.
He misunderstands my position and since you agree with him, you equally misunderstand me as well.
Possibly the case, but if so, it seems that you need to write more clearly, so that you are not misunderstood.
I haven’t seen you make that argument, nor have I seen Wells use that argument. However, in forum discussions in the past I have seen people try to squirm out of the rather obvious conclusion that DNA sequence is a very dominant force in determining development and morphology. I was simply outlining the border of the current scientific consensus in case you ran across material that may have stepped over that border.
I have been clear enough, but you and Mercer still misunderstand. To be regarded as a molecular means of inheritance, a biomolecule must be stable, able to store information, have a mechanism to replicate itself with a high degree of fidelity, etcetera. Only genomes (mostly DNA and some RNA) have these qualities. Why this seems to elude John and Rum baffles me.
My point is that not just any somatic cells become germ cells.
Here is a good summary at a basic level:
https://embryology.med.unsw.edu.au/embryology/index.php/Primordial_Germ_Cell_Development
I would say that we have not done enough chimeric nuclear transplant experiments to know that. Many more will need to be done to preserve endangered species through the foreseeable future.
Again, that organization is information not stored in DNA.
Come on, Michael. Put down the goalposts. You’re going from “inherited information” in general to “molecular means of inheritance.” Those aren’t even close to being the same thing.
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False, because some of it is heritable. Heritable information is solely stored in DNA, which is passed down to progeny alongside other cellular constituents.
There are no goalposts to put down. I have been very clear that the information only DNA hold is heritable.
Plenty of it is to falsify your claim of “all.”
That is why if you encapsulate an in vitro transcription/translation system (available for the last 10-15 years) and a genome in a phospholipid sphere, you’ll never get an organism.
That’s false. The goalpost you added was “molecular,” btw.
Sorry I edited my response to that.
Yes, that’s because DNA is a passive store of hereditary information in the absence of other appropriate cellular constituents.
Not true. Go through all my comments on this thread and its pretty obvious I have consistently argued that only DNA keeps heritable information.
You edited your comment and now it makes no sense:
I don’t understand the first sentence. I am pointing out that the organization is inherited.
Yes it is inherited directly, following cytokinesis, but some of it goes away after a time. What persists through generations is the actual heritable information, found in just DNA.
Life loses its cellular organization? Absurd.
Please stop this.
The organization of the cell is absolutely essential information that is not stored anywhere in DNA and never goes away.
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You misunderstand. I specifically mentioned that following cell division, cellular organization (composed of and sustained by DNA, proteins, RNAs, membrane lipids and others) is directly inherited by progeny. After a time, all these directly inherited constituents and the information they carry are lost, asides from DNA and the information it carries. To recreate these degraded components so as to maintain cellular organization, existing non-DNA cellular constituents have to rely on the information stored in DNA. Clear enough?
It never goes away because of DNA.
No, I really don’t.
Correct so far!
Wrong. The organization, which is information, is never lost.
No, the fundamental organization of the cell is not stored in DNA.
I don’t understand why that’s a point. What does it tell us that’s relevant?