COMPARATIVE STUDY OF MEMBRANE PERMEABILITY 631 



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Discussion 



^ Davis : I might say that in one aspect of active membrane transport I see no 

 basis for believing that the fundamental mechanism of transport of electrolytes, 

 including mineral ions, is going to be very different from that of stereospecific 

 organic molecules. This is one of the reasons why I am reluctant to use the word 

 "enzyme" in relation to these carriers, because we cannot very well speak of an 

 enzymic conversion of potassium to some product on the way in. 



