Roberto Zivieri
University of Messina, Messina, Italy
Title: The Problem of Entropy in Minimum Living Systems: a Classical Thermodynamic Approach
Biography
Biography: Roberto Zivieri
Abstract
An analytical model to compute the rate of entropy density, defined as the time derivative of the entropy, in minimum living systems is developed basing on the equations of heat and mass diffusion and on classical statistical thermodynamics. The model is applied to glucose catabolism in normal and cancer cells. It is shown that the rate of internal entropy is mainly due to irreversible chemical reactions, and that the rate of external entropy is mostly correlated to the heat flow towards the intercellular environment. It is found that the ratio between the rates of entropy associated to respiration and fermentation processes is invariant for heat and irreversible reactions. Prigogine’s minimum energy dissipation principle is reformulated using the notion of entropy density acceleration, defined as the derivative of the rate of entropy density, applied to glucose catabolism. For a single cell the calculated entropy density acceleration is finite and negative and approaches, as a function of time, a zero value at global thermodynamic equilibrium for heat and matter transfer independently of the cell type and the metabolic pathway. This trend is in agreement with the local formulation of the second principle of thermodynamics. These results could open the route towards other investigations focusing on the statistical thermodynamic description of glucose catabolism in human cells with special regard to entropy generation, balance and exchange.