The Krebs Cycle Electron Transport Chapter 9 2

The Krebs Cycle & Electron Transport Chapter 9. 2

Krebs Cycle (aka Citric Acid Cycle) • Aerobic part of cellular respiration, it requires oxygen • The process of breaking pyruvic acid into carbon dioxide (CO 2) using oxygen (O 2) • This process releases energy

• Takes place in mitochondrion • Pyruvic acid (3 C) from glycolysis is broken down to CO 2 (leaves 2 C) & electrons are removed to change NAD+ to NADH • Acetyl-Co. A (2 C) + 4 C = citric acid (6 C)

• Citric acid (6 C) is broken down to 5 C and then to 4 C (CO 2 & NADH formed each time) • 1 ATP & 1 FADH 2 are also formed • 4 NADH formed

Electron Transport Chain • ETC uses the high energy electrons from the Krebs Cycle to convert ADP into ATP • ETC composed of carrier proteins in the inner membrane of the mitochondrion

• At the end of ETC is an enzyme that combines efrom the ETC with H & O to form water • Oxygen serves as final eacceptor of the ETC

• 2 e- moving down the ETC transports H+ across the membrane; charge differential is created and used to form ATP

• Most of the ATP produced during cellular respiration is made during the Electron Transport Chain

Totals Glycolysis = Krebs cycle = electron transport = Total 2 ATP 32 ATP 36 ATP

• Video: http: //www. copernicusproject. ucr. edu/ssi/HSBiology. Resources. htm Glycolysis and Cellular Respiration