Chemiosmosis

• The pumping of hydrogen ions into the intermembrane space creates a proton gradient
• Proton gradient

  • characterized by a higher concentration of hydrogen ions in the intermembrane space than in the matrix.
• As hydrogen ions move down their concentration gradient, they power ATP synthase, which results in the synthesis of ATP molecules.
• When one hydrogen ion passes through the ATP synthase, one ATP molecule by adding one phosphate molecule to ADP
• Chemiosmosis is the process by which hydrogen ions are used to power ATP synthase to phosphorylate ADP into ATP.
• In the electron transport chain, no ATP molecules are produced yet
• 1 NADH = 3 Hydrogen ions = 3 ATP molecules
• complex II is not capable of pumping hydrogen

  ions to the intermembrane space
• 1 FADH2 = 2 hydrogen ions = 2 ATP molecules