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Thermodynamics and Biology 



I. The Role of Thermodynamics in Biology 



Thermodynamics is one of the major fields of classical physics. The 

 concepts of energy and of its changes of form are central to thermody- 

 namics. Many physicists and chemists have come to regard this approach 

 as the most basic and most important. Accordingly, they consider the 

 application of thermodynamics to biological systems as the central core 

 of biophysics. 



Thermodynamics can be applied to various aspects of living systems. 

 The chapters in this part of the text illustrate some of these applications. 

 They include the behavior of enzyme systems, the transport of mole- 

 cules against chemical and electrical gradients, and the molecular basis 

 of nerve conduction. There is virtually no field of biological science to 

 which the concepts of thermodynamics cannot be applied. 



Thermodynamics has long been recognized to be of prime importance 

 to biophysics. One of the most distinguished of the early biophysicists of 

 the current century, A. V. Hill, is best known for his heat measurements 

 on muscles. Other biophysicists have followed this path toward an 

 understanding of life. 



Unfortunately, to apply thermodynamics to biological systems one 

 must know something about thermodynamics. It is inherently a 



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