Answer;
ETS reactions (electron transport system reactions)
Step-by-step explanation;
-ATP is produced by the process of cellular respiration that takes place inside a cell in organelles called mitochondria.
Cellular respiration involves three stages, namely; glycolysis, citric acid cycle -and electron transport chain. During the process of cellular respiration (aerobic), 38 ATP molecules are produced ( 2 ATP from glycolysis, 2 ATP from citric acid cycle and 34 ATP from electron transport system). Thus, the ETS accounts for the largest amount of ATP produced during cellular respiration.