Cellular Respiration Sugar [Glucose – 6 carbons] 2 ATP 4 ATP Glycolysis 2 NAD+ Net Gain: 2 ATP 2 NADH 2x [3 Carbon Molecule] Without Oxygen [Anaerobic] With O2 [Aerobic Respiration] 2x 2 NADH 2x [CO2] 4x [CO2] Fermentation [Alcohol or Lactic Acid] 6 NADH 2 FADH2 Krebs Cycle 2 ATP [CO2] + 2 NAD+ O2 Electron Transport System H2O 32 ATP Total: 36 ATP C6H12O6 + 6O2 6CO2 + 6H2O + 36 ATP