Now, the vertical component is basically exposed to the matrix of the mitochondria. But the horizontal component, this component, lies entirely in the membrane, the inner membrane of the mitochondria. So the entire function of protein complex One is to accept those high energy electrons from NADH molecules and to move those electrons along a special pathway within the complex that we're going to focus on in detail in electra to come. And those electrons ultimately are transferred onto the electron carrier molecule known as coenzyme Q Ubiquinone that we're going to look at in just a moment. Now, this protein complex number one also acts as a proton pump. So the fact that we have the movement of electrons within this complex that generates a form of energy that allows us to actually move these H plus ions across this membrane to this side and that ultimately allows us to actually generate a proton electrochemical gradient that will ultimately be used by the ATP synthase molecule to form the ATP molecule.