Krebs Cycle

• The Krebs cycle takes place in the matrix of the mitochondria
• 1. The 2C compound acetyl CoA from the link reaction enters the Krebs cycle and  combines with the 4C acid oxyloacetate, forming the 6C compound Citrate
• 2. Decarboxylation of the 6C citrate results in the formation of the 5C compound
• 3. Decarboxylation of the 5C compound results in the formation of 4C oxaloacetate
• 4. At four points within the Krebs cycle, 

  dehydrogenation occurs and hydrogen is released. At three of these points, hydrogen is taken up by NAD to form NADH
• 5. The remaining hydrogen combines with FAD to form FADH
• 6. One molecule of ATP is produced directly by the Krebs cycle, this occurs by the transfer of a phosphate group from an immediate compound to ADP, known as substrate level phosphorylation
• 7. The products from ONE cycle are 1 ATP, 2 CO2, 3 NADH and 1 FADH
• 8. The krebs cyle occurs TWICE as there are two acetyl CoA molecules produced in the link reaction
• 9. Therefore, the net result of one complete turn of the citric acid cycle is the production of 2 ATP, 4 CO2, 6 NADH and 2 FADH