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To: allmendream
It is DIRECTLY involved in the actual response made to the stress because it DIRECTLY introduces mutations that ARE the response that is made.

Nope. You obviously cannot establish that every cellular response to a stress involves the use of error DNA_polymerase in the solution. Specifically, the example from slide 22.

Why, are you ignorant enough to STILL insist that all cell stress leads to cell death?

Why are you so stupid as to not admit it was a distractor. That is why I placed, "Be that as it may" immediately subsequent to that statement. It is a definition question in my opinion. If you wish to define a stress as anything that provokes a response to it as stress that is fine. If you wish to define a stress as something that is harmful to the organism that is also fine, but I will not give up my French Fries or coconut oil because you think them stressful.

404 posted on 10/07/2011 1:04:20 PM PDT by AndrewC
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To: AndrewC
I don't need to establish that EVERY cellular response to a stress involves the use of error prone DNA polymerase to illustrate WHY error prone DNA polymerase is expressed in a bacterial cell during stress.

Some novelty in evolution comes about through regulated cellular responses. The stress response that leads to expression of error prone DNA polymerase is one such regulated cellular response - and it DOES lead to novelty in evolution.

Care to describe to me how some 8% or less of the bacterial genome can be a “tote bag” for innumerable ‘discarded’ mutations for every possible gene in the bacterial genome for every possible stress it might encounter?

Besides if you even agree that there IS such a thing as novelty in evolution - as Shapiro posits - why would it have to come from some “tote bag”?

If it was there but unused until it was needed it wouldn't be “novel” now would it?

405 posted on 10/07/2011 1:13:20 PM PDT by allmendream (Tea Party did not send the GOP to D.C. to negotiate the terms of our surrender to socialism.)
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To: AndrewC
“Seems to be pretty straightforward. If it did not “change”, “it” would die, which it does eventually. But to the more immediate concern, the bacteria “adapts”. The real question is how it “knows” it is under stress in order to react to the stress.” AndrewC

No, bacteria do not all eventually die. All bacteria alive today are descended from bacteria that DID NOT DIE - they split and live on in the form of at least one living ‘descendant’.

“The point is that if the cell dies, it was a stress. If it does not die, it wasn't a stress.” AndrewC

So how does a cell “know” it is under stress you ask? Apparently by your ludicrous definition - when it is DEAD it knows it was under stress!

A stress is something that interferes with the living processes of a cell. It can be an antibiotic, a toxin, heat, cold, high pressure, low pressure - anything that can be detected through molecular mechanisms that causes interference in the living processes of the cell.

These molecular mechanisms that detect cellular distress start a signaling transduction pathway that activates transcription factors that enable the expression of stress response genes.

One of these stress response genes is error prone DNA polymerase.

Why it is expressed during stress is because, as you helpfully point out - if it didn't change it would (be more likely to) die.

Now what is changing when error prone DNA polymerase is used during cellular reproduction instead of high fidelity DNA polymerase?

The entire genome, not just psuedogenes, not just things from your absurdly small “tote bag” - NO! The ENTIRE GENOME is subject to change - and good thing too - because during during extreme heat stress (for example) a large % of genes would need mutations that made them more stable at high temperatures in order to survive and thrive at higher and higher temperatures.

407 posted on 10/07/2011 1:26:03 PM PDT by allmendream (Tea Party did not send the GOP to D.C. to negotiate the terms of our surrender to socialism.)
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