1. Cell Respiration An Animated Tour

2. Glycolysis If NO O 2 Glucose Mitochondria Cytoplasm

3. Glycolysis If NO O 2 Glucose Mitochondria Cytoplasm

4. Glycolysis If NO O 2 Glucose Mitochondria ATP Cytoplasm

5. Glycolysis If NO O 2 Glucose Pyruvate Mitochondria ATP Cytoplasm

6. Glycolysis If NO O 2 Glucose Pyruvate Mitochondria ATP Cytoplasm The process stalls here, because the flow of electrons (and H+ ions) stops.

7. Glycolysis If NO O 2 Glucose Pyruvate Mitochondria ATP Cytoplasm Only 2 ATP are made.

8. Glycolysis If NO O 2 Glucose Pyruvate Mitochondria ATP Cytoplasm In order to restart the flow of electrons in the absence of O 2, the cell must FERMENT the pyruvate.

9. And they produce CARBON DIOXIDE Fermentation I Glycolysis If NO O 2 Fermentation Glucose Pyruvate Cytoplasm Mitochondria ATP CO 2 Alcohol They produce ALCOHOL H2OH2O They produce WATER There are TWO types of fermentation.Yeasts use ALCOHOLIC FERMENTATION.This process is IRREVERSIBLE because carbon is lost.

10. Fermentation II Glycolysis If NO O 2 Fermentation Glucose Pyruvate Cytoplasm Mitochondria ATP Many bacteria & some animal muscle cells perform LACTIC ACID FERMENTATION. Pyruvate is converted to LACTIC ACID. Lactic acid In bacterial fermentation, lactic acid builds up in environment (sauerkraut or yogurt) & lowers pH. This build up of lactic acid creates an OXYGEN DEBT (muscle soreness). During periods of intense activity, leg muscles operate without O 2, using lactic acid fermention. As activity slows, O 2 can again reach the muscle tissue and the lactic acid is converted back to pyruvate... The pyruvate now enters aerobic respiration to “repay” the oxygen debt!

11. Glycolysis Glycolysis Animation

12. Kreb’s Cycle Kreb's Cycle Animation

13. Electron Transport Electron Transport Chain Animation

14. Aerobic Pathways Glycolysis Glucose Pyruvate O 2 present Kreb’s Cycle Electron Transport Chain O2O2 Cytoplasm Mitochondria ATP (Matrix)(Cristae) Pyruvate enters the KREB’s CYCLEThe Kreb’s cycle acts like a molecular blender, systematically dismantling pyruvate, breaking bonds to produce CO 2... CO 2 Convert some bond energy to ATP... ATP And strip HIGH ENERGY e - and H + ions from the fuel molecules. The electrons & H + ions are passed to the ELECTRON TRANSPORT CHAIN for further processing... The e - power the ETC ion pump, forcing the H + ions against their concentration gradient into the INNER MEMBRANE SPACE. The H + ions are moved by CARRIER molecules NADHFADH The H + ions LEAK out of this space through ATP SYNTHETASE enzymes which use this force to PHOSPHORYLATE ADP  ATP ATP Finally, O 2 molecules are REDUCED by GAINING the LOW ENERGY e - and the H + ions to form WATER. H2OH2O Overall ATP YIELD is 2 + 2 + 34 = 38 2 2 34

15. The Whole Enchilada (Una vez más) Glycolysis If NO O 2 Fermentation Glucose Pyruvate O 2 present Kreb’s Cycle NADHFADH Electron Transport Chain O2O2 H2OH2O ATP Cytoplasm Mitochondria CO 2 ATP (Matrix)(Cristae) Alcohol CO 2 Lactic acid H2OH2O

16. THE END