James A. Barham
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Member # 50
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posted 10. June 2002 07:36
Most of the debate between ID theorists and Darwinians has classically focused on the question of origins. ID theorists seem to be willing pretty much to accept the mainstream view of the cell as a mind-bogglingly complex mechanism, but then point out (quite rightly) that the Darwinian account of the origins of such mechanisms is ridiculously inadequate.
However, I have become convinced that the mainstream view of the occurrent functioning of the cell is itself inadequate, and must be supplemented by some sort of theory of how cellular function can be so coordinated in space and time. As I advertised on another thread, I have been researching the theory of coherent cellular action of John G. Watterson. I would like to ask my ID colleagues to think about the following problem, as nicely articulated by Watterson in the following passage:
[After discussing his own theory of a quantal unit or "pixel" consisting of protein+ordered water, which can cohere with other such quantal units in wave fashion, he goes on to say the following:]
"We can extend this concept and propose that the row of domains represents the supramolecular complex composed of enzymes involved in a metabolic pathway. Then only when the metabolites are located at their respective catalytic sites between the clusters and domains, can the transition [to coherent action] take place. Since it encompasses the whole complex, each metabolite is converted into its product, which can then all be moved along one position in the sequence of active sites. This co-operative mechanism ensures that each molecule entering the complex as the initial metabolite is fully converted into the final product. The cell must operate in some such way as this, in order to avoid the cytoplasmic space from becoming filled with metabolic debris. There is no experimental evidence that the subcellular space is a concentrated solution of metabolites, each waiting for its chance encounter with the correct enzyme to continue along its pathway. This problem cannot be solved in the classical picture in which we have soluble metabolites colliding with soluble enzymes, because the diffusion mechanism is random and can therefore only disrupt the order needed for the operation and maintenance of sequential processes. If enzyme catalysis were diffusion controlled, the cell would become clogged with metabolites of all types. Furthermore, once freely dissolved in the cytoplasm, a portion of them would never re-enter the metabolic flow because of the chance nature of diffusion. To illustrate this point, the classical picture of cellular activity can be likened to traffic flow in a busy city where there are no rules of the road." (J.G. Watterson, "The Pressure Pixel---Unit of Life?", BioSystems, 1997, 41: 141--152; p. 149)
Now, I don't think this is necessarily an insuperable obstacle from an ID perspective. One might envision saying that the cooperativity (the "rules of the road") will be explained via additional constraints or boundary conditions that have not been identified yet (a sort of "hidden variables" argument). And, indeed, there is abundant empirical evidence for structure (cytoskeleton, microtrabecular lattice, compartmentation on all scales) that would provide such contraints.
But I just wonder how, in general, my ID colleagues would react to this passage and to the idea that the mainstream statistical picture is utterly inadequate to account, not just for origins, but equally for the occurrent functioning of the cell.
[ 10 June 2002, 07:49: Message edited by: James A. Barham ]
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