ATP synthase is which creates ATP from ADP and phosphate. In both the light reactions of photosynthesis AND the electron transport chain of cellular respiration, this reaction is driven by a/an gradient (meaning there is a difference in concentration across the membrane). a nucleic acid, electron an enzyme, proton an enzyme, electron a carbohydrate, proton QUESTION 12 Enzymes catalyze reactions by: lowering the activation energy lowering the energy of products raising the activation energy raising the energy of reactants QUESTION 13 NADH and FADH2 are the electron transport chain. O reduced, accept electrons from oxidized, donate electrons to oxidized, accept electrons from reduced, donate electrons to forms of those respective cofactors/coenzymes. This means they will be able to 2 p 2 p the