The versatility of catabolism Plasma membrane

Fermentation enables cell to produce ATP w/o O2 aerobic anaerobic *Fermentation generates ATP by substrate-level phosphorylation

Cellular Respiration: one more time! SUMMARY: Organic + Oxygen Carbon + Water + Energy Compounds Dioxide C6H12O6 + 6 O2 6 CO2 + 6 H2O + energy Redox reactions release energy *Redox reactions *loss of an electron = oxidation *gain of an electron = reduction C6H12O6 + 6 O2 6 CO2 + 6 H2O oxidation reduction

*Dehydrogenases *Nicotinamide adenine dinucleotide *ATP can be synthesized in one of two ways: Substrate-level phosphorylation Oxidative phosphorylation

Cellular Respiration: an overview 3 metabolic stages: *glycolysis *Krebs cycle *electron transport chain

Glycolysis harvests chemical energy by oxidizing glucose to pyruvate

The Krebs cycle: energy-yielding oxidation cytosol mitochondrial matrix per pyruvate per glucose 1 ATP 2 ATP 4 NADH 8 NADH 1 FADH2 2 FADH2

Electron transport and ATP synthesis FADH2 Some more accounting: *For every NADH that transfers e- to ETC, 3 H+ are pumped across the inner mt membrane *For every FADH2, 2 H+ are pumped across the inner mt membrane

Fermentation enables cell to produce ATP w/o O2 aerobic anaerobic *Fermentation generates ATP by substrate-level phosphorylation