And once these electrons are extracted, they move along the proteins, the enzymes of the electron transport chain. And that ultimately allows some of these proteins to actually pump the H plus ions to the intermembrane space, the space between the inner and the outer membrane of the mitochondria. And this establishes an electrochemical gradient for the hydrogen ions. So this takes place here, here and here. Then the electrons are ultimately accepted by that diatomic oxygen to form water molecules. And in the final step of the electron transport chain, the fact that we have an unequal distribution of H plus ions basically means we have an electrochemical potential difference between the two sides of our membrane.