50 



A SYMPOSIUM ON RESPIRATORY ENZYMES 



slow to supply oxygen in time, and the muscle has to rely almost 

 entirely on the anaerobic energy of glycolysis. 



The Efficiency of Aerobic and Anaerobic Metabolism 



Fermentations are energy-yielding rearrangements of the atoms 

 constituting the glucose molecule. These are oxidation-reduction 

 reactions in which, after cleavage, one part of the molecule is 



Figure 2.— Oxygen consumption and blood lactate with strenuous work. The 

 excessive lactate formation signifies predominantly anaerobic energy supply. 

 A moderate rise of oxygen consumption occurs first after completion of the 

 work in tlie period of restitution. The slow fall of lactate in tlie blood indicates 

 a relatively slow removal of lactate by resynthesis or oxidation. (After O. Bang, 

 ref. I.) 



