The Theory of Open Systems in Physics and Biology

Abstract

A summary consideration of the implications of the fact that living systems are "open systems," that is, systems in which there is a continuous inflow and outflow of materials with a consequent change in the components, while classical thermodynamics is largely based on "closed systems,v in which no material enters or leaves, tending to equilibrium. While basic chemical and physical principles do apply to living systems, due consideration must be given to the fact that living systems are "open systems." Such phenomena as self-regulation, growth, maintenance of concn. gradients by living tissues, equinfinal-ity (final state independent of initial state within wide limits), and numerous other characteristics of living systems which upon the surface appear to depart from conditions detd. by classical thermodynamics, are interpretable in terms of basic physical and chemical principles when the living system is considered as an "open system.".