Th electron transport chain

The first stage to oxidative phosophorlation is called the Electron transport chain (ETC). During this stage, reduced electron carriers in the form of NADH and FADH2 enter the complexes of ETC. Complex 1 strips NADH of its electrons and pumps them to coenzyme Q. In addition to this complex 1 will pump protons to the intermembrane area. Complex 2 strips FADH2 of its electrons and donates them to coenzyme Q as well. However, Complex 2 does NOT pump protons. Coenzyme Q will then donate the electrons it recieves to complex 3, which pumps more protons to the intermembrane space. In turn, complex 3 donates electrons to Cytochrome C, a water soluable protein which can move around the intermembrane space. Cytochrome C transports electrons to Complex 4. Complex 4 pumps protons to the intermembrane space as well, and donates its electrons to the final electron reciever, oxygen. This process produces H2O. It is importan for these complex to pump protons to the intermembrane space to set up a proton gradient. The proton gradient is used to power the last part of oxidative phosophorylation, ATP synathse. Protons from the intermembrane space essentially store energy and release it by moving through the gradiant and back into the mitochondrial matrix through ATP synthase. For every 3 protons which pass through the protein, 1 ATP is created.