Abstract: | The flight muscle preparations of the dragonfly Pantala flavescens and the aquatic beetle Cybister confusus showed extremely low levels of lactic dehydrogenase activity and high levels of alpha-glycerophosphate dehydrogenase (insoluble) activity. The activities of these two enzymes in the leg muscle of the beetle were approximately the same (1:1), but lactic dehydrogenase activity was several times higher than that in the flight muscles of both Insects. These results have been interpreted as indicating the high energy-yielding demands of the flight muscles during continuous sustained activity, while the leg muscles of the beetle which are involved in swimming activity derive their energy predominantly through anaerobic glycolysis. |