1. Cellular Respiration (Chapter 9)

3. Energy source Autotrophs: Producers Plants, algae and some bacteria Make own organic molecules Heterotrophs: Consumers

4. Energy All activities an organism performs requires energy

5. Cellular respiration C 6 H 12 O 6 + 6 O 2 ---> 6 CO 2 + 6 H 2 O + ATP

6. Cellular respiration

7. Cellular Respiration Catabolic Enzymes break down substances Harvest energy from C-H bonds Or other chemical bonds Organic compounds + oxygen ⇨ Carbon Dioxide + water + energy

8. Cellular respiration Aerobic respiration Chemical energy is harvested Presence of oxygen Anaerobic respiration Process occurs without oxygen Fermentation

9. Anaerobic Glucose to lactate (muscle cells) Glucose to alcohol (yeast cells) Does not yield as much energy

10. Cellular Respiration Exergonic -686kcal/mole (-2,870kJ/mole) Redox reaction Glucose is oxidized, oxygen is reduced Energy stored in glucose makes ATP 38 ATP generated ATP stores energy for use in cellular functions

11. Redox reaction becomes oxidized becomes reduced

12. Vocabulary NAD/NADH FAD ETC Phosphorylation Chemiosmosis ATP Synthase

13. NAD & NADH NAD: Nicotinamide adenine dinucleotide NAD+ oxidized form NADH reduced form NAD + traps electrons from glucose Function as energy carrier

14. NAD & NADH Dehydrogenase (enzyme) Removes a pair of hydrogen atoms from glucose Transfers one proton and 2 electrons to NAD + H-C-OH + NAD + ⇨ -C=O + NADH + H + Used to make ATP

15. NAD + 2 e − + 2 H + 2[H] (from food) Nicotinamide (oxidized form) Reduction of NAD + 2 e − + H + NADH Nicotinamide (reduced form) Oxidation of NADH H+H+ H+H+ Dehydrogenase

16. FAD Flavin adenine dinucleotide Transfers electrons

17. Electron transport chain Located inner membrane of mitochondria Plasma membrane (prokaryotes) Series of molecules (mostly proteins)

18. Electron transport chain Electrons fall to oxygen In a series of energy releasing steps High potential energy to low Energy released generates ATP

19. Electron transport chain Free energy, G Controlled release of energy for synthesis of ATP 2 H + + 2 e – 2 H + 1 / 2 O 2 (from food via NADH) ATP 1 / 2 O 2 2 H + 2 e – Electron transport chain H2OH2O

20. Phosphorylation Addition of a phosphate group to a molecule ATP is formed by a phosphorylation reaction 1. Substrate-level phosphorylation 2. Oxidative phosphorylation

21. Substrate phosphorylation Enzyme transfers a phosphate from a organic substrate molecule ADP to make ATP Direct formation Glycolysis and Krebs cycle

22. Oxidation phosphorylation Energy from electron transport chain Synthesis ATP Adds an inorganic phosphate to ADP

23. Chemiosmosis Energy-coupling mechanism Energy stored in hydrogen ion gradient across membrane Makes ATP from ADP

24. H+H+ 2 H+H+ ADP + P i ATP Chemiosmosis ATP synthase

25. ATP Synthase Enzyme helps make ATP Located in membrane Changes ADP to ATP Uses energy from a proton gradient across membrane

26. INTERMEMBRANE SPACE Rotor H+H+ Stator Internal rod Catalytic knob ADP + P i MITOCHONDRIAL MATRIX ATP

27. The Reactions (Cell Respiration) Glycolysis Krebs cycle (citric acid cycle) Electron transport chain (oxidative phosphorylation)

28. Cellular respiration

31. Glycolysis Happens in cytoplasm Starts with glucose Yields: 2 pyruvate (3 carbons) molecules 4 ATP (net of 2 ATP) & 2 NADH 10 enzyme catalyzed reactions to complete

32. Glycolysis Every living organism can carry out glycolysis Occur in aerobic & anaerobic Does not require oxygen Oxygen present the Krebs cycle will begin

33. Glycolysis Part one (priming) First 5 reactions are endergonic 2 ATP molecules attach 2 phosphate groups to the glucose Produces a 6 carbon molecule with 2 high energy phosphates attached

34. Glycolysis Part two (cleavage reactions) 6 carbon molecule is split into 2 3-carbon molecules each with a phosphate (G3P)

35. Glycolysis Part three (energy harvesting reactions) In two reactions 2- G3P molecules are changed to pyruvate 4 ATP molecules are made (net of 2) An energy rich hydrogen is harvested as NADH (2NADH)

36. GLYCOLYSIS: Energy Investment Phase Glucose

37. GLYCOLYSIS: Energy Investment Phase Glucose 6-phosphate ATP ADP Glucose Hexokinase 1

38. GLYCOLYSIS: Energy Investment Phase Glucose 6-phosphate ATP ADP Glucose Hexokinase Phosphogluco- isomerase Fructose 6-phosphate 1 2

39. GLYCOLYSIS: Energy Investment Phase 3 Fructose 6-phosphate ATP ADP Fructose 1,6-bisphosphate Phospho- fructokinase

40. GLYCOLYSIS: Energy Investment Phase 3 45 Fructose 6-phosphate ATP ADP Glyceraldehyde 3-phosphate (G3P) Fructose 1,6-bisphosphate Dihydroxyacetone phosphate (DHAP) Phospho- fructokinase Aldolase Isomerase

41. GLYCOLYSIS: Energy Investment Phase ADP Glucose 6-phosphate Fructose 6-phosphate ATP ADP Glyceraldehyde 3-phosphate (G3P) Fructose 1,6-bisphosphate Dihydroxyacetone phosphate (DHAP) Glucose Hexokinase Phosphogluco- isomerase Phospho- fructokinase Aldolase Isomerase 1 2 5 4 3

42. GLYCOLYSIS: Energy Payoff Phase 4 Glyceraldehyde 3-phosphate (G3P) Dihydroxyacetone phosphate (DHAP) Aldolase Isomerase 5 6 Triose phosphate dehydrogenase 2 NAD + 2 H + NADH 2 2 2 2 1,3-Bisphospho- glycerate

43. GLYCOLYSIS: Energy Payoff Phase 4 Glyceraldehyde 3-phosphate (G3P) Dihydroxyacetone phosphate (DHAP) Aldolase Isomerase 5 6 7 Triose phosphate dehydrogenase 2 NAD + 2 H + NADH 2 2 2 2 2 ADP 1,3-Bisphospho- glycerate 3-Phospho- glycerate Phospho- glycerokinase 2 2 ATP

44. 8 9 Phospho- glyceromutase 3-Phospho- glycerate 2-Phospho- glycerate 222 Enolase Phosphoenol- pyruvate (PEP) 2 H2OH2O GLYCOLYSIS: Energy Payoff Phase

45. Figure 9.9bb-3 8 9 10 Phospho- glyceromutase 3-Phospho- glycerate 2-Phospho- glycerate 222 Enolase Phosphoenol- pyruvate (PEP) Pyruvate kinase 2 2 ATP ADP 2 H2OH2O 2 GLYCOLYSIS: Energy Payoff Phase

46. Glycer- aldehyde 3-phosphate (G3P) Triose phosphate dehydrogenase 6 1,3-Bisphospho- glycerate 3-Phospho- glycerate 2-Phospho- glycerate Phosphoenol- pyruvate (PEP) Pyruvate Phospho- glycerokinase Phospho- glyceromutase Enolase Pyruvate kinase 2 NAD + 7 8 9 10 2NADH + 2 H + 2 2 2 2 222 2 2 2 2H2OH2O ATP ADP

47. Electron shuttles span membrane + 2 ATP 2 NADH or 2 FADH 2 GLYCOLYSIS Glucose 2 Pyruvate 2 NADH

48. Glycolysis Glucose converted to pyruvate. First half uses 2 ATP Forms 2 separate G3P (glyceraldehyde 3- phosphate)

49. Glycolysis Second half generates 4 ATP, 2 NADH & 2 pyruvate Net results are 2 ATP, 2 NADH and 2 pyruvate Takes place in the cytoplasm

50. Oxidation of pyruvate Pyruvate is changed into acetyl-CoA First carboxyl group is removed Leaves as carbon dioxide 2 carbon molecule called acetate remains

51. Oxidation of pyruvate Pyruvate dehydrogenase Multienzyme complex Combines acetate (acetyl group) with a coenzyme called coenzyme A. Product is acetyl-CoA Plus one NADH

52. Oxidation of pyruvate Pyruvate dehydrogenase Largest known enzyme 60 subunits Process occurs within mitochondria Acetyl-CoA is end product of the break down of fats and proteins too

53. Fig. 9-10 CYTOSOLMITOCHONDRION NAD + NADH+ H + 2 1 3 Pyruvate Transport protein CO 2 Coenzyme A Acetyl CoA