Question

How one molecule of NADH gives rise to 3 molecules of ATP and One molecule of FADH2 produces two molecules of ATP. As they are only present for up taking H+ and releasing it in? I couldn't understand?

Answer 1

Electron transport chain (ETC)

1. Electron Transport Chain is a series of compounds where it makes use of electrons from electron carriers to develop a chemical gradient.
2. It could be used to power oxidative phosphorylation. The molecules present in the comprises enzymes that are protein complexes or proteins, peptides and much more.
3. NADH produces 3 ATP during the ETC (Electron Transport Chain) with oxidative phosphorylation because NADH gives up its electron to Complex I, which is at a higher energy level than the other Complexes.
4. When Complex I transfers the electron to Complex III, energy is given off to pump protons across the membrane, creating a gradient.
5. The electron moves again to Complex IV and again pumps more electrons across the membrane.
6. Because NADH started with Complex I, it had more chances to pump more protons across the gradient, which powers the ATP synthase and gives us 3 ATP per molecule of NADH.
7. FADH2 produces 2 ATP during the ETC because it gives up its electron to Complex II, bypassing Complex I.
8. By bypassing Complex I, we missed a chance to pump protons across the membrane, so fewer protons have been pumped by the time we get to Complex IV.
9. Protons still have been pumped, enough to fuel 2 ATP created by ATP synthase.