[Differentiation of cells and organs from the point of view of the second law of thermodynamics and the "protein-machine" concept].
Differentiation of cells and organs arises on the basis of excessiveness at thermodynamically stable process of DNA synthesis as a thermodynamic system with a great relaxation time and alternative number for degrees of freedom. Entropy normalization for DNA is controlled by the exterior effects for DNA causing a thermodynamic unstable (quick) process of protein synthesis. While DNA is interacting with the medium, this process is stabilized not by a priori information which, probably, presupposes this in DNA, but by the ecologic recess inside the cell. The chain of reverse effect assumes transmission of DNA degrees of freedom of controlling effects not only from its neighboring environment, but both from the cell and the organism as a whole. A possibility of accidental occurrence in the natural selection is defined both by the above and the specification of the state equations for DNA which determines relative limitation of variants synthesized with its participation of key reaction groups in proteins. Evolution has no aim, but the principle of filling the ecologic recess creates an apparent expediency that does not differ from the presupposed one. The question--why are the state equations for DNA of this type--ultimately resolves itself into the question why the inner structure of a nucleus is of the kind it exists, i.e., at present it is beyond the possibility of scientific analysis. But with the existing equations of state the leading reason of differentiation for cells and organs is the second thermodynamics principle as tending to maximal chaos limited by the internal and external conditions.
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D002454:Cell Differentiation; D004247:DNA / Q000096:biosynthesis / Q000737:chemistry; D013816:Thermodynamics
D004247:DNA
Differentsirovka kletok i organov s tochki zreniia vtorogo nachala termodinamiki i kontseptsiia "belok-mashina".