In photosynthesis, the electron that travels through the electron transport chain in the thylakoid membrane comes from _____ . In cellular respiration, a molecule of _____ supplies the electron that travels through the electron transport chain.
Answer is NADH. NADH is very good electron donating agent. So it donates electron and changed to NAD+. The electron from NADH travels from higher energy level to lower energy level releasing energy some of which is used to maintian electrochemical gradient by pumping H+ ion into the intermemebrane space. These electron combine with molecular oxygen to form water at the end of the electron transport chain, while the H+ ion fows back to the matrix, combine with ATP Synthase which increase proton flow to synthesize ATP.
