Question

ATP molecules produced respectively by $NADH\left(H^{+}\right)$ and $FAD{H}_2$ during electron transport are

• A. 3 and 2
• B. 1 and 1
• C. 2 and3
• D. 3 and 3

Answer 1

The correct option is A 3 and 2

During Krebs cycle and glycolysis, NADH and FADH2 are produced which travel to inner membrane and dump their electrons into the membrane. This loss of electrons is a redox reaction and converts NADH into AD and FADH2 into the FAD. The membrane proteins in the electron transport chain are protein pumps. The passage of electrons across them pumps the protons across the inner membrane from the matrix to intermembrane space. Each NADH pups 3 protons whereas each FADH2 pumps 2 protons. This pumping of electrons across the inner membrane caused a concentration gradient oF hydrogen atoms across the membrane. By diffusion, the hydrogen ions travel back into the matrix to reach equilibrium. They can do so by traveling through a special channel found in the membrane called ATP synthase. This channel uses the energy of passage of hydrogen ions to make ATP. For each proton that passes one ATP is made. This is why each NADH makes 3 ATP and each FADH2 makes 2 ATP.

Thus, the correct answer is option A.