SALT ABSORPTION AND METABOLISM 



81 



^ 0-4- 



a. 



O 



o 



0-3 



^ 2 



o 



E 



0-1 



001 0-02 003 004 

 [KCL], M 



005 006 



o 



(b) 



_L 



001 0-02 0-03 0-04 0-05 006 

 [KCl], M 



Fig. 29. Salt absorption and respiration 



a. Rates of salt absorption (•) and salt respiration (C) by carrot tissue 



placed in solutions of potassium chloride (redrawn from Robertson and 



, ,, , ^ , . salt absorbed (gm. mol.) ^ 

 Wilkins, 1948); b. Values of the ratio — -. — : — -^ A for carrot 



salt respiration (gm. mol.) 

 tissue placed in solutions of potassium chloride. Calculated from the data 

 of Fig. 29a. (redrawn from Robertson and Wilkins 1948). 



for nitrate, it may well be asked what reason there is for believing 

 that it functions in the case of chloride either, 



(b) There are cases in which salt uptake is apparently linked to 

 other oxidases than cytochrome, for example, ascorbic acid oxidase 

 (Russell, 1954). Ascorbic acid oxidase seems to mediate part of the 



