ABSTRACT: Biological organisms are open thermodynamic systems with metabolism. Therefore, most processes are not in equilibrium. Thermodynamic forces and fluxes drive biological processes under consumption of energy and dissipation of entropy. Such processes are irreversible. The understanding of nonequilibrium processes is important to analyze molecular reactions, protein function and metabolism in biology. This course introduces into the thermodynamics of irreversible processes and into the application of these concepts to elementary biological reactions (e.g. ion channel activities and ion pumps). Under certain conditions stable fluxes (stationary states) develop, or dissipative structures can form. Criteria for defining such states are formulated. As an important example, this course also introduces into the foundations of the physics of nerve pulses. This includes the treatment of the basic physical features of nerves, electrical conductance through cell membranes, cable theory, ion channels and the Hodgkin-Huxley model in particular, which forms the nonequilibrium basis of the accepted models for the action potential. We contrast this classical theory of nerves by an adiabatic thermodynamic treatment of nerves leading to the possibility of solitons in membranes, thus forming an alternative basis for the origin of the nervous pulse that is based on reversible physics. The difference between reversible and dissipative processes is discussed. This includes channel activities and their lifetimes.
For physicists, chemists, biochemists and related subject after the bachelor.
LITERATURE: There will be handouts that are sufficient for understanding. The following is recommended reading: "Modern Thermodynamics: From Heat Engines to Dissipative Structures (Paperback) by D. Kondepudi and I. Prigogine" - Selected publications by Onsager, Einstein, Prigogine, Hodgkin and Huxley etc.
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