acceptor molecule

acceptor molecule

a molecule that has a high affinity for electrons, usually passing them on to another acceptor molecule in a series (called an ELECTRON TRANSPORT SYSTEM). As each acceptor receives an electron it becomes reduced and then oxidized as the electron is given up (see REDOX POTENTIAL). Each reduction-oxidation reaction is catalysed by a different enzyme, energy being gradually released with each electron transfer. Acceptor molecules (e.g. CYTOCHROME) are vital in AEROBIC RESPIRATION and PHOTOSYNTHESIS.