<P> The last process in aerobic respiration is oxidative phosphorylation , also known as the electron transport chain . Here NADH and FADH , which contain the energy in the form of electrons , deliver their electrons to the inner membranes of the mitochondrion to power the production of ATP . Oxidative phosphorylation contributes the majority of the ATP produced , compared to glycolysis and the Krebs cycle . While the ATP count is glycolysis and the Krebs cycle is two ATP molecules , the electron transport chain contributes , at most , twenty - eight ATP molecules . A contributing factor is due to the energy potentials of NADH and FADH . As they are brought from the initial process , glycolysis , to the electron transport chain , the energy stored in them are now utilized . A second contributing factor is that cristae , the inner membranes of mitochondria , increase the surface area and therefore the amount of proteins in the membrane that assist in the synthesis of ATP . Along the electron transport chain , there are separate compartments , each with their own concentration gradient of H + ions , which are the power source of ATP synthesis . To convert ADP to ATP , energy must be provided . That energy is provided by the H+ gradient . On one side of the membrane compartment , there is a high concentration of H+ ions compared to the other . The shuttling of H+ to one side of the membrane is driven by the exergonic flow of electrons throughout the membrane . These electrons are supplied by NADH and FADH as they transfer their potential energy . Once the H+ concentration gradient is established , a proton - motive force is established , which provides the energy to convert ADP to ATP . The H+ ions that were initially forced to one side of the mitochondrion membrane now naturally flow through a membrane protein called ATP synthase , a protein that converts ADP to ATP with the help of H+ ions . </P>
the majority of the atp molecules derived from the breakdown of glucose are generated by
Oxidative phosphorylation