Overview of Cellular Respiration Cellular respiration is the process that releases energy from food in the presence of oxygen. Cellular respiration captures the energy from food in three main stages: • glycolysis • the Krebs cycle • the electron transport chain Glycolysis does not require oxygen.The Krebs cycle and electron transport chain both require oxygen.verview of Cellular Respiration Cellular respiration is the process that releases energy from food in the presence of oxygen. Cellular respiration captures the energy from food in three main stages: • glycolysis • the Krebs cycle • the electron transport chain Glycolysis does not require oxygen.