16 Discussion 



Chance : But some of our data indicate that hexokinase can produce 

 ADP much faster than the mitochondria can utihze it. 



Krebs : Is that in muscle? 



Chance: No, that is in yeast cells and ascites tumour cells under 

 special conditions of a metabolic transient. 



Lipmann : We talk as if we were dealing with a homogeneous system, 

 whereas we are dealing with a highly heterogeneous system. We cannot 

 just ignore that and speak as if we could set up general conditions where 

 every substrate meets another one, and meets a catalyst uninhibited by 

 membranes or permeability barriers. It would be more useful to think 

 in terms of heterogeneity rather than in terms of homogeneity. We 

 forget that so easily. 



