domingo, 20 de janeiro de 2008

The Living Organism: A Self-regulating System

The inter-relations between elements, happenings or individuals,
as far as they have a regular and stable character, become organizational.
Every organizational inter-relation supposes the existence and the game of attractions, of affinities, of possibilities of connections
or of communication between the elements or individuals.

Edgar Morin

The scientific revolution determined by the ideas that came from the theories of organization, communication, and information, has led to the conception of the organization of the living beings, formulated by Henri Atlan. The term self-organization was introduced in 1947 by W. Ross Ashby.

The organisms are self-regulative systems, adaptive, capable of self-duplication. For that, they have to acquire energy from the environment, and use it to their biological work. With this aim, the living things act thermodynamically as irreversible chemical machines. In order to be self-regulating and adaptive, control and information are essential. Cybernetic mechanisms must provide at least the basis for the steady state and dynamical characteristics, as well as the necessary adaptability to survival.

Thus, while the ergonic component of the living organism may be better understood in terms of free flux of energy, the cybernetic component compares itself to the flux of information which is necessary for the maintenance of the steady state (homeostasis in the sense attributed by Cannon, 1932). The mechanisms of control affect the ergonic component of life in all the various levels of organisation, from the molecular to the global.

The operational reason for the existence of the cybernetic mechanism is the stabilisation and the conservation of the ergonic component. Adaptability, control, survival, and stability are facets of the same central biological characteristic.

There are two main components to analyze biological systems. One of them includes all the elements which are relative to acquisition, transference and utilization of energy, which allows the organism to grow, to move and to do work. The other consists in the group that operates on detection, processing, retention of information which allows the control of what the organism does and with which velocity. Essential to the maintenance of life, both components are intimately associated to sustain the steady state. The ergonic component of the living organism identifies itself with the flux of energy in the living beings.

The flux of energy across the organism is canalised by the synthesis, storage and utilization of the high energy bonding of the phosphates. In the first half of the 20th century, the phenomena of transference of energy in glucose, in the tricarboxylic acid cycle and in the system of transference of electrons were elucidated. Its basic pattern has been the same from the anaerobic micro-organisms until the plants and superior animals. The cybernetic component is compared to the flux of information.

Understanding where and how such regulative systems act is, with no doubt, the biggest challenge of current Biology.

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