Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings PowerPoint TextEdit Slides for Biology, Seventh Edition Neil Campbell and Jane Reece Chapter 9 Cellular Respiration: Harvesting Chemical Energy

Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Figure 9.1 The giant panda is consuming fuel to power the work of life

Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Light energy ECOSYSTEM CO 2 + H 2 O Photosynthesis in chloroplasts Cellular respiration in mitochondria Organic molecules + O 2 ATP powers most cellular work Heat energy Figure 9.2 Energy flow and chemical recycling in ecosystems

Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings CH 4 H H H H C OO O O O C HH Methane (reducing agent) Oxygen (oxidizing agent) Carbon dioxideWater +2 O 2 CO 2 +Energy+2 H 2 O becomes oxidized becomes reduced ReactantsProducts Figure 9.3 Methane combustion as an energy- yielding redox reaction

Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings NAD + H O O OO–O– O O O–O– O O O P P CH 2 HO OH H H HOOH HO H H N+N+ C NH 2 H N H N N Nicotinamide (oxidized form) NH 2 + 2[H] (from food) Dehydrogenase Reduction of NAD + Oxidation of NADH 2 e – + 2 H + 2 e – + H + NADH O H H N C + Nicotinamide (reduced form) N Figure 9.4 NAD + as an electron shuttle H+H+ H+H+

Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings H / 2 O 2 2 H 1 / 2 O 2 (from food via NADH) 2 H e – 2 H + 2 e – H2OH2O 1 / 2 O 2 Controlled release of energy for synthesis of ATP ATP Electron transport chain Free energy, G (b) Cellular respiration (a) Uncontrolled reaction Free energy, G H2OH2O Explosive release of heat and light energy + Figure 9.5 An introduction to electron transport chains

Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Figure 9.6 An overview of cellular respiration Glycolsis GlucosePyruvate ATP Substrate-level phosphorylation Mitochondrion

Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Figure 9.6 An overview of cellular respiration ATP Substrate-level phosphorylation Mitochondrion Glycolsis GlucosePyruvate ATP Substrate-level phosphorylation Citric acid cycle

Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Figure 9.6 An overview of cellular respiration Electrons carried via NADH Glycolsis GlucosePyruvate ATP Substrate-level phosphorylation Electrons carried via NADH and FADH 2 Citric acid cycle Oxidative phosphorylation: electron transport and chemiosmosis ATP Substrate-level phosphorylation Oxidative phosphorylation Mitochondrion

Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Electron shuttles span membrane CYTOSOL 2 NADH 2 FADH 2 2 NADH 6 NADH 2 FADH 2 2 NADH Glycolysis Glucose 2 Pyruvate 2 Acetyl CoA Citric acid cycle Oxidative phosphorylation: electron transport and chemiosmosis MITOCHONDRION by substrate-level phosphorylation by substrate-level phosphorylation by oxidative phosphorylation, depending on which shuttle transports electrons from NADH in cytosol Maximum per glucose: About 36 or 38 ATP + 2 ATP + about 32 or 34 ATP or Figure 9.16 ATP yield per molecule of glucose at each stage of cellular respiration

Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Enzyme ATP ADP Product Substrate P + Figure 9.7 Substrate-level phosphorylation

Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Glycolysis Citric acid cycle Oxidative phosphorylation ATP 2 ATP 4 ATP used formed Glucose 2 ATP + 2 P 4 ADP + 4 P 2 NAD e H + 2 NADH + 2 H + 2 Pyruvate + 2 H 2 O Energy investment phase Energy payoff phase Glucose 2 Pyruvate + 2 H 2 O 4 ATP formed – 2 ATP used 2 ATP 2 NAD e – + 4 H + 2 NADH + 2 H + Figure 9.8 The energy input and output of glycolysis Net

Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Figure 9.9 A closer look at glycolysis: energy investment phase H OH ATP ADP Hexokinase Glucose-6-phosphate 1 H H H H H OH HO OH Glucose O CH 2 OH CH 2 O H H O H OH HO OH P H Glycolysis Citirc acid cycle Oxidative phosphorylation ATP

Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Figure 9.9 A closer look at glycolysis: energy investment phase Dihydroxyacetone phosphate Glyceraldehyde- 3-phosphate H H H H H OH HO OH CH 2 O H H H H O H OH HO OH P CH 2 O P H O H HO H CH 2 OH P O CH 2 O O P HO H H OH O P CH 2 C O CH 2 OH H C CHOH CH 2 O O P ATP ADP Hexokinase Glucose Glucose-6-phosphate Fructose-6-phosphate ATP ADP Phosphoglucoisomerase Phosphofructokinase Fructose- 1, 6-bisphosphate Aldolase Isomerase O H CH 2 OH Glycolysis Citirc acid cycle Oxidative phosphorylation ATP

Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Figure 9.9 A closer look at glycolysis: energy payoff phase 6 2 NAD + NADH H + Triose phosphate dehydrogenase 2 P i 2 P C CHOH O P O CH 2 O 2 O–O– 1, 3-Bisphosphoglycerate 2 ADP 2 ATP Phosphoglycerokinase CH 2 OP 2 C CHOH 3-Phosphoglycerate Phosphoglyceromutase O–O– C C CH 2 OH H O P 8 7 O 2-Phosphoglycerate O

Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Figure 9.9 A closer look at glycolysis: energy payoff phase 2 NAD + NADH H + Triose phosphate dehydrogenase 2 P i 2 P C CHOH O P O CH 2 O 2 O–O– 1, 3-Bisphosphoglycerate 2 ADP 2 ATP Phosphoglycerokinase CH 2 O P 2 C CHOH 3-Phosphoglycerate Phosphoglyceromutase O–O– C C CH 2 OH H O P 2-Phosphoglycerate 2 H 2 O 2 O–O– Enolase C C O P O CH 2 Phosphoenolpyruvate 2 ADP 2 ATP Pyruvate kinase O–O– C C O O CH Pyruvate O

Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings CYTOSOLMITOCHONDRION NADH + H + NAD CO 2 Coenzyme A Pyruvate Acetyle CoA S CoA C CH 3 O Transport protein O–O– O O C C CH 3 Figure 9.10 Conversion of pyruvate to acetyle CoA, the junction between glycolysis and the citric acid cycle

Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings NAD + Figure 9.11 An overview of the citric acid cycle ATP 2 CO 2 3 NAD + 3 NADH + 3 H + ADP + P i FAD FADH 2 Citric acid cycle CoA Acetyle CoA NADH + H + CoA CO 2 Pyruvate (from glycolysis, 2 molecules per glucose) ATP Glycolysis Citric acid cycle Oxidative phosphorylation

Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Figure 9.12 Closer look at the citric acid cycle Acetyl CoA Oxaloacetate Citrate Isocitrate SCoA SH H2OH2O C CH 3 O OC COO – CH 2 COO – CH 2 HO C COO – CH 2 COO – CH 2 HCCOO – HOCH 1 2 Glycolysis Oxidative phosphorylation Citirc acid cycle ATP

Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Figure 9.12 Closer look at the citric acid cycle Acetyl CoA Citrate  -Ketoglutarate Isocitrate Citric acid cycle SCoA SH NADH NAD + CO 2 CoA SH CoA S H2OH2O C CH 3 O C COO – CH 2 HOC COO – CH 2 COO – CH 2 HC COO – HOCH COO – CH 2 CO COO – CH 2 C O COO – 1 CH 2 SUCCINYL CoA + H Oxaloacetate Glycolysis Oxidative phosphorylation Citirc acid cycle ATP

Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Acetyl CoA Oxaloacetate Citrate Fumarate Succinate Succinyl CoA  -Ketoglutarate Isocitrate SCoA SH NADH FADH 2 FAD GTP GDP NAD + ADP P i NAD + CO 2 CoA SH CoA SH CoA S + H + H2OH2O C CH 3 O OCCOO – CH 2 COO – CH 2 HO C COO – CH 2 COO – CH 2 HCCOO – HO CH COO – CH HC COO – CH 2 COO – CH 2 CO COO – CH 2 CO COO – Glycolysis Oxidative phosphorylation ATP Citirc acid cycle ATP Figure 9.12 Closer look at the citric acid cycle + H + Citric acid cycle

Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Figure 9.12 Closer look at the citric acid cycle Acetyl CoA NADH Oxaloacetate Citrate Malate Fumarate Succinate Succinyl CoA  -Ketoglutarate Isocitrate Citric acid cycle SCoA SH NADH FADH 2 FAD GTP GDP NAD + ADP P i NAD + CO 2 CoA SH CoASH CoA S H2OH2O + H + H2OH2O C CH 3 O O C COO – CH 2 COO – CH 2 HO CCOO – CH 2 COO – CH 2 HCCOO – HOCH COO – CH CH 2 COO – HO COO – CH HC COO – CH 2 COO – CH 2 CO COO – CH 2 CO COO – Glycolysis Oxidative phosphorylation NAD + ATP Citirc acid cycle ATP + H +

Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Figure 9.13 Free-energy change during electron transport Glycolysis Citirc acid cycle Oxidative phosphorylation ATP H2OH2O O2O2 NADH FADH 2 FMN FeS O FAD Cyt b Cyt c 1 Cyt c Cyt a Cyt a 3 2 H  2 I II III IV Multiprotein complexes Free energy (G) relative to O 2 (kcl/mol)

Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Figure 9.14 ATP synthase, a molecular mill MITOCHONDRIAL MATRIX INTERMEMBRANE SPACE H+H+ H+H+ H+H+ H+H+ H+H+ H+H+ H+H+ H+H+ P i + ADP ATP A rotor within the membrane spins clockwise when H + flows past it down the H + gradient. A stator anchored in the membrane holds the knob stationary. A rod (or “stalk”) extending into the knob also spins, activating catalytic sites in the knob. Three catalytic sites in the stationary knob join inorganic Phosphate to ADP to make ATP.

Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Figure 9.15 Chemiosmosis couples the electron transport chain to ATP synthesis Oxidative phosphorylation electron transport and chemiosmosis Glycolysis ATP Inner Mitochondrial membrane H+H+ H+H+ H+H+ H+H+ H+H+ ATP P i Protein complex of electron carners Cyt c I II III IV (Carrying electrons from food) NADH + FADH 2 NAD + FAD + 2 H / 2 O 2 H2OH2O ADP + Electron transport chain Electron transport and pumping of protons (H + ), which create an H + gradient across the membrane Chemiosmosis ATP synthesis powered by the flow Of H + back across the membrane ATP synthase Q Oxidative phosphorylation Intermembrane space Inner mitochondrial membrane Mitochondrial matrix Citirc acid cycle

Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Figure 9.17 Fermentation 2 ADP + 2 P iP i 2 ATP Glycolysis Glucose 2 NAD + 2 NADH 2 Pyruvate 2 Acetaldehyde 2 Ethanol (a) Alcohol fermentation 2 ADP + 2 P i 2 ATP Glycolysis Glucose 2 NAD + 2 NADH 2 Lactate (b) Lactic acid fermentation H H OH CH 3 C O – O C CO CH 3 H CO O–O– CO CO O C O C OHH CH 3 CO Pyruvate +2 H +

Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Glucose CYTOSOL Pyruvate No O 2 present Fermentation O 2 present Cellular respiration Ethanol or lactate Acetyl CoA MITOCHONDRION Citric acid cycle Figure 9.18 Pyruvate as a key juncture in catabolism

Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Amino acids Sugars Glycerol Fatty acids Glycolysis Glucose Glyceraldehyde-3- P Pyruvate Acetyl CoA NH 3 Citric acid cycle Oxidative phosphorylation Fats Proteins Carbohydrates Figure 9.19 The catabolism of various molecules from food

Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Glucose Glycolysis Fructose-6-phosphate Phosphofructokinase Fructose-1,6-bisphosphate Inhibits Pyruvate ATP Acetyl CoA Citric acid cycle Citrate Oxidative phosphorylation Stimulates AMP + – – Figure 9.20 The control of cellular respiration