1. Cellular Respiration LEOxidized and GEReduced H + + e - -Therefore H atoms are removed electrons are also removed. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. energy glucose Reduction Oxidation 6H 2 O6CO 2 6O 2 C 6 H 12 O 6 + + +

2. NAD + and FAD Coenzyme of oxidation-reduction Electron Carriers

4. Cellular Respiration Glycolysis Prep Phase (acetyl CoA) Citric Acid Cycle (Kreb’s Cycle) Electron Transport Chain (ETC)

5. An overview of cellular respiration (Layer 1)

6. Glycolysis  Glucose is broken down into two molecules of pyruvate Occurs in the cytoplasm ATP is formed Does not use oxygen

7. Glycolysis Takes place in the cytoplasm NAD +

8. What’s Happened so far? Glycolysis O 2 Used ? Glucose C now Product: ATP # NADH # GlycolysisNo2 Pyruvates22 pyruvate glucose

9. Pyruvate as a key juncture in catabolism

10. If O 2 is NOT available Fermentation, an anaerobic process, occurs in the cytoplasm.  During fermentation, glucose is incompletely metabolized to lactate, or to CO 2 and alcohol (depending on the organism).

11. Fermentation Helps Produce Numerous Food Products Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

12. Alcoholic Fermentation Pyruvate + NADH Ethanol + CO 2 + NAD + Vinegar

13. Lactic Acid Fermentation Pyruvate + NADH Lactic Acid + NAD +

14. If O 2 is available Preparatory (prep) reaction, a aerobic process, occurs in the mitochondria. Occurs in mitochondria Two carbons are released as CO 2 (one from each pyruvate) 14

15. What’s Happened so far? Krebs Cycle Original C of glucose are now ATPNADHFADH 2 Glycolysis2 pyruvate22 Acetyl CoA formation 2 CO 2 & 2 acetyl CoA 2 Krebs Cycle Total glucose

16. An overview of cellular respiration (Layer 2)

17. Citric acid cycle Occurs in the matrix of the mitochondrion and produces NADH and FADH 2 Releases 4 carbons as CO 2 Produces 2 ATP molecules 17

18. What’s Happened so far? Krebs Cycle Original C of glucose are now ATPNADHFADH 2 Glycolysis2 pyruvate22 Acetyl CoA formation 2 CO 2 & 2 acetyl CoA 2 Krebs Cycle4 more CO 2 262 Total6 CO 2 4102 glucose

19. An overview of cellular respiration (Layer 3)

20. Mitochondrion Structure and Function 20 © Dr. Donald Fawcett and Dr. Porter/Visuals Unlimited Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Cristae: location of the electron transportchain (ETC) Matrix: location of the prep reaction and the citric acid cycle outer membrane inner membrane intermembrane space cristae matrix 45,0003X

21. Organization and Function of the Electron Transport Chain Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 2 O2O2 1 2 + 2 P H+H+ e : e : Electron transport chain high energy electron ATP channel protein Intermembrane space ATP synthase complex low energy electron cytochrome oxidase cytochrome c NADH-Q reductase cytochrome reductase coenzyme Q NADH Matrix FADH 2 FAD + NAD + 2 e-e- 2 ADPATP 32 ADP or 34 4 ADP netATP 4 ATP total 2ADP 2ATP Glycolysis glucosepyruvate Preparatory reaction Citric acid cycle Electron transport chain and chemiosmosis NADH and FADH 2 NADH e-e- e-e- e-e- e-e- e-e- e-e- 32 or 34 H+H+ H+H+ H+H+ H+H+ H+H+ H+H+ H+H+ H+H+ H+H+ H+H+ H+H+ H+H+ H+H+ H+H+ H+H+ H+H+ H+H+ H+H+ ATP ADP H2OH2O H+H+ H+H+ H+H+ H+H+ H+H+ H+H+ H+H+ H+H+ H+H+ H+H+ H+H+ H+H+ H+H+ H+H+ H+H+ H+H+ H+H+ ATP Chemiosmosis

22. Electron Transport Chain (ETC) Extracts energy from NADH & FADH 2 Passes electrons from higher to lower energy states Produces 32 or 34 molecules of ATP

24. Max of 36 ATP per Glucose

25. Substrate-level ATP Synthesis Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. P P P enzyme ADP ATP BPG 3PG

26. Inside the Mitochondria Electron Transport Chain (ETC) Location:  Eukaryotes: cristae of the mitochondria  Aerobic prokaryotes: plasma membrane The electron transport chain  Receives electrons from NADH & FADH 2  Produces ATP by oxidative phosphorylation Oxygen serves as the final electron acceptor  Oxygen combines with hydrogen ions to form water

27. *H+ is pumped against its gradient into the mitochondrial matrix *Energy for active transport comes from electrons

28. Inside the Mitochondria Energy yield from glucose metabolism:  Net yield per glucose: From glycolysis – 2 ATP From citric acid cycle – 2 ATP From electron transport chain – 32 or 34 ATP  Energy content: Reactant (glucose) 686 kcal Energy yield (36 ATP) 263 kcal Efficiency is 39% The rest of the energy from glucose is lost as heat

29. Energy rich molecules: carbohydrates, fats, and proteins Catabolism : Break down molecules usually exergonic (release energy) Anabolism build molecules: usually endergonic (consume energy) 29 ATP Electron transport chain proteinscarbohydratesfats amino acids glucose fatty acids glycerol acetyl CoA Glycolysis pyruvate ATP Citric acid cycle

30. Photosynthesis vs. Cellular Respiration 30 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. O2O2 O2O2 enzymesgrana Photosynthesis NADP + CH 2 O NADPH CO 2 enzyme-catalyzed reactions NADH enzymes H2OH2O membrane ATP production via chemiosmosis ADP ATP H2OH2O membrane Cellular Respiration NAD + cristae CH 2 O CO 2