MEMBRANE POTENTIALS 



227 



different values for CI2 shown in table 35. When it is assumed that a 

 = 0.1 N, the values shown in table 36 will be obtained. 



When the "colloid" is of the nature of an anion, then all of the 

 above derivations may be directly applied by simply substituting 

 oh for h and n for cl. Since ohi/oho = h2/hi equation (5) above 

 becomes 



hi 



2 n2 



V 



+ -^1 + 



2 m 



TABLE 35 



TABLE 36 



and the two tables shown above retain their vaUdity in this case by 

 merely changing hi/h2 to h2/hi and CI2 to n2. 



Let us now attempt to derive from the above consideration such 

 useful physiological appHcations as may be possible at present. We 

 shall take the case of a cell whose content represents a 0.01-0.1 molar 

 solution of protein, which, insofar as it is ionized, we shall consider as 

 being moleculary dispersed. The protein, at the pH of the tissue 

 fluids, must be assumed to be in the form of anions, insofar as it is 

 ionized in general. The cell is surrounded by a membrane imper- 

 meable to protein and is bathed in a protein-free NaCl solution, 

 approximately 0.1 A''. In such a case we should expect a membrane 



