Control of Rate of Intracellular Respiration 61 



1 I I I r 



TIME (MINS.) 



Fig. 2. Respiratory control in guinea-pig 

 heart sarcosomes, isolated in 0-23 m 

 sucrose, 0-005 m ATP, pH 7-4, and 

 suspended in 0-25 m sucrose, 0-001 m 

 ATP, pH 7-4. Reaction mixture as in 

 Fig. 1. Curve 1, no further addition. 

 Curve 2, ADP (2-7 [xmoles) added at 19 

 min. Curve 3, 0-02 m glucose + hexo- 

 kinase present from beginning. The 

 measurement of Og uptake commenced 

 8 min. after the beginning of the experi- 

 ment. 



and inorganic phosphate, but have been made to account for 

 other findings (Myers and Slater, 19576; Slater, 1955, 1958; 

 Purvis and Slater, 1959). 



AH, 

 A 



2 + B + I 



-I + x 



A 

 X 



BHo 



I + A 



(1) 

 (2) 



