 The energy stored from the process of respiration in reduced compounds (such as NADH and FADH) is used by the electron transport chain to pump protons into the inter membrane space, generating the electrochemical gradient over the inner mitochrondrial membrane.In photosynthetic eukaryotes, the electron transport chain is found on the thylakoid membrane.Here, light energy drives the reduction of components of the electron transport chain and therefore causes subsequent synthesis of ATP.