<prompt> Which of the following is not involved in generation of proton gradient?NADPH dehydrogenaseCoenzyme Q cytoreductaseSuccinate CoQ reductaseCytochrome reductase  <response>: Proton gradient : The inner mitochondrial membrane, as such, is impermeable to protons H and hydroxyl ions OH-. The transpo of electrons through ETC is coupled with the. translocation of protons H across the inner mitochondrial membrane coupling membrane from the matrix to the intermembrane space. The pumping of protons results in an electrochemical . or proton gradient. This is due to the. accumulation of more H ions low pH on the outer side of the inner mitochondrial membrane than the inner side. The proton . gradient developed due to the electron flow in the respiratory chain is sufficient to result in the synthesis of ATP from ADP and Pi. Ref : Biochemistry by U. Satyanarayana 3rd edition Pgno : 229 