156 PHYSIOLOGY OF MICROORGANISMS 



This is true whether energy exist as potential energy in the form of 

 rest or as kinetic energy in the active form. "In every modification 

 of a material system, not affected by forces foreign to a system, the 

 sum of its potential and kinetic energies remains constant." This 

 statement represents the great law of Conservation of Energy. To 

 determine the total energy of a body is difficult for it usually contains 

 potential and kinetic energy which may not find expression in measur- 

 able units. It follows that "the total intrinsic energy of a body or 

 system of bodies is never known. When bodies mutually react it is 

 only the difference of the energy of each body in two states which is 

 considered. If a body has less energy in its actual than in its standard 

 state the expression for its energy is negative." The functionings 

 of a living organism may well be said to be the energizing powers of 

 such organism. These powers are maintained by the food consumed, 

 part of which enters into the synthesis of new protoplasm or in renewal 

 processes, and part furnishes the energy for the work performed. 

 Whether the energy goes to constructive and reconstructive purposes in 

 the maintenance of the mechanism or whether to the manifest liberation 

 of energy as work, it is desirable to remember that the ramifications of 

 either route are multitudinous, intricate and mostly concealed. The 

 principle of the Conservation of Living Forces states "that the differ- 

 ence of the force-functions (or work) at the beginning and at the end 

 of the motion of a system is equal to the difference of the vires viva 

 (kinetic energies) at the beginning and the end of the motion." This 

 is readily seen to represent only measurable and definite performance 

 and does not in any sense represent potential possibilities. 



If living energy is functional energy or functioning then an under- 

 standing of it with any degree of comprehensiveness means that it is 

 to be found in the study of the many functional processes of the body 

 in detail. To this attention is directed. 



SOLUTIONS 



When any substance is placed in or is associated with another 

 substance in such a manner as to enable both to establish a uniform 

 ionic, molecular and particulate mixture, such a combination is called 

 a solution. In a true solution, this combination, in which the ionic or 

 molecular components are intimately merged or blended and are 



