February 13th, 2020

  • mns2012

Комплиментарность структуры и функции в биосистемах по Патти

Pattee H. H. (1978) Biological systems theory: Descriptive and constructive complementarity. In: Klir G. J. (ed.) Applied general systems research. Plenum, New York: 511–520.

. . . . The introduction of this complementarity into systems de­scription has profound epistemological and methodological signif­icance. By recognizing that all living systems depend on internal, rate-independent, linguistic descriptions, we are forced to intro­duce the classical symbol-matter (or subject-object) dualism into the system itself. This is no metaphor or analogy; it is a literal interpretation of what we normally mean by the symbol-matter dis­tinction. The genetic DNA is a linear, discrete set of symbols that is interpreted by the transducing, protein-synthesizing constraints of the cell to construct and control the structure and dynamics of the organism in its environment. This internal description is also responsible for the growth of new degrees of freedom, new parts, and new functions into the systems that are competent to read it. The reading process is relatively rate- independent, but its execution requires rate-dependent control that is accomplished by constructing thousands of enzymes whose dynam­ical description would each require thousands of degrees of free­dom. Of course all these complex dynamical processes could not be described in the cell. The trick of genetic description (Cf. Lofgren [Note 9] ; von Neumann [Note 25] ) is that the description of the constraints that harness the dynamics is relatively simple and abstract (i.e., obey arbitrary syntactic rules), while the dynamics that they constrain are incredibly complex and entirely physical (i.e., obey natural laws).Biologists now know many of the key molecular hardware mechanisms underlying reproduction, development and evolution, although much of the molecular hardware remains to be discovered. The molecular biological descriptions of the gene and its mechanism of expression have been interpreted by some biologists as a total reduction of life to physics, but to others the details of molecular structure have only served to emphasize the basic ambiguity between structure and function. As a consequence, many biologists are now shifting from questions of hardware structure to the questions of the pro­gramming and control of the morphologies and activities of orga­nisms. We are finding that useful explanations of living systems’ behavior require a dualistic description that recognizes the linguistic, prescriptive activity of life as complementary to the dynamical hardware activity. Longuet-Higgins [Note 10] has characterized life as “programmed matter” which succinctly focuses on this essential complementarity. The earlier emphasis in biology on the anatomical and molecular structures is being augmented with the concepts of biological languages and programs.