The process aerobic production of ATP is termed ox- idative phosphorylation. To understand the processes involved in aerobic ATP generation, it is convenient to think of aerobic ATP
production as a three-stage pro- cess (Fig. 3.17). Stage 1 is the generation of a key two- carbon molecule, acetyl-CoA. Stage 2 is the oxidation of acetyl-CoA in the Krebs cycle. Stage 3 is the process of oxidative phosphorylation (i.e., ATP formation) in the electron transport chain (i.e., respiratory chain).