The final phase of cellular respiration is oxidative phosphorylation. Both the electron transport chain and chemiosmosis make up oxidative phosphorylation. During this phase of cellular respiration, all of the NADH and FADH2 that were produced in other phases of cellular respiration (glycolysis, the link reaction, and Krebs cycle) are used to make ATP. The process occurs in the protein complexes embedded in the inner mitochondrial membrane.