I'O IWSSIUM IN YEAST CELLS 



921 



'•' In the first mentioned case we start with radioactive nutrition solution, in the second case with 

 radioactive yeast. 



(2) Due to increase respectively decrease in tlie potassium content of the yeast. 



potassium and nutrient solution potassium. The figures are calculated 

 from the data of the chemical analyses. In the case of a full interchange, 

 the ratio of the ^^K and of the total potassium content of the yeast and 

 the nutrient solution must obviously be the same. 



In column 5, the values found for the distribution coefficient are 

 stated. 



If no exchange took place the values of column 5 should correspond 

 to the values of column 3 while, in the case of a full interchange, the 

 values of column 5 would correspond to the values of column 4. In the 

 case of a partial interchange, the values of column 3 w^ould lie between 

 the corresponding values of column 3 and column 4. The difference 

 between the values of columns 4 and 5 will decrease wdth increasing 

 interchange. Since, with increasing interchange, the ^^K content of the 

 nutrient solution, respectively of the yeast, is getting more and more 

 "diluted" ]jy non-active potassium moving in the opposite direction we 



