1. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings PowerPoint Lectures for Biology: Concepts and Connections, Fifth Edition – Campbell, Reece, Taylor, and Simon Lectures by Chris Romero Chapter 6 How Cells Harvest Chemical Energy

2. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings 1/26/11 – “C” Day Objective: To understand how eukaryotic cells harvest energy Do Now: What is the overall chemical equation for Cellular Respiration? Where does this occur in eukaryotic cells? Today: 1.Complete Calorimetry Lab 2.Complete Data Table, Answer Post-Lab Analysis 12 - 14, Do Further Investigation in blank space provided (under data table)

3. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings 1/28/11 – “D” Day Objective: To understand how eukaryotic cells harvest energy Do Now: What types of food do you predict have the most energy? Extra Credit – Bring in a Nutrition Facts label tomorrow! Today: 1.Complete Calorimetry Lab 2.Complete Data Table, Answer Post-Lab Analysis 12 & 14, Do Further Investigation in blank space provided (under data table)

4. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings 1/31/11 – “E” Day Objective: To understand how eukaryotic cells harvest energy Do Now: What types of food have the most energy? Did you bring in a Nutrition Label? Today: 1.Check/Discuss/Complete Calorimetry Lab 2.Continue Chapter 6 Notes HW – Read through 6.14 and complete up to Exercise 8 for TOMORROW!

5. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings 1/31/11 – “E” Day Objective: To understand how eukaryotic cells harvest energy Do Now: What is the role of NADH and FADH 2 in the process of cellular respiration? Where are they created? Today: 1.Check in HW 2.Continue Notes!

6. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings 2/1/11 – “F” Day Objective: To understand how eukaryotic cells harvest energy Do Now: What are the products of glycolysis? Where do they go?

7. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings 2/2/11 – “A” Day Objective: To understand how eukaryotic cells harvest energy Do Now: What steps follow glycolysis in cell respiration? What are the products?

8. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings 2/14/11 – “C” Day Objective: To understand how exercise influences cellular respiration in humans Do Now: How will you measure CO 2 production for your experiment? Why is a reference tube necessary?

9. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings How Is a Marathoner Different from a Sprinter? Human muscles contain two different types of muscle fibers –That perform differently under different conditions

10. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings The different types of muscle fibers –Function either aerobically, with oxygen, or anaerobically, without oxygen Cellular respiration –Is the process by which cells produce energy aerobically

11. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings INTRODUCTION TO CELLULAR RESPIRATION Photosynthesis and cellular respiration provide energy for life Cellular respiration makes ATP and consumes O 2 –During the oxidation of glucose to CO 2 and H 2 O

12. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings Photosynthesis uses solar energy –To produce glucose and O 2 from CO 2 and H 2 O CO 2 H2OH2O Glucose O2O2 ATP ECOSYSTEM Sunlight energy Photosynthesis in chloroplasts Cellular respiration in mitochondria (for cellular work) Heat energy   Figure 6.1

13. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings 6.1 Breathing supplies oxygen to our cells and removes carbon dioxide Breathing provides for the exchange of O 2 and CO 2 –Between an organism and its environment CO 2 O2O2 O2O2 Bloodstream Muscle cells carrying out Cellular Respiration Breathing Glucose  O 2 CO 2  H 2 O  ATP Lungs Figure 6.2

14. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings 2/3/11 – “A” Day Objective: To understand how eukaryotic cells harvest energy Do Now: What steps follow glycolysis in cell respiration? What are the products?

15. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings 6.2 Cellular respiration banks energy in ATP molecules Cellular respiration breaks down glucose molecules –And banks their energy in ATP C 6 H 12 O 6 CO 2 6H2OH2OATPs Glucose Oxygen gas Carbon dioxide 6 Water Energy O2O2 6 + + + Figure 6.3

16. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings CONNECTION 6.3 The human body uses energy from ATP for all its activities ATP powers almost all cellular and body activities Table 6.4

17. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings 6.4 Cells tap energy from electrons transferred from organic fuels to oxygen Electrons lose potential energy –During their transfer from organic compounds to oxygen BASIC MECHANISMS OF ENERGY RELEASE

18. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings When glucose is converted to carbon dioxide –It loses hydrogen atoms, which are added to oxygen, producing water C 6 H 12 O 6 6 O 2 6 CO 2 6 H 2 O Loss of hydrogen atoms (oxidation) Gain of hydrogen atoms (reduction) Energy (ATP)Glucose + ++ Figure 6.5A

19. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings 6.5 Hydrogen carriers such as NAD + shuttle electrons in redox reactions In an oxidation-reduction (redox) reaction –the loss of electrons is called oxidation (LEO) –the gain of electrons is called reduction (GER)

20. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings Dehydrogenase removes electrons (in H atoms) from fuel molecules (oxidation) –And transfers them to NAD + (nictotinamide adenine dinucleotide) (reduction) Figure 6.5B O H H O2H Reduction Dehydrogenase (carries 2 electrons) NAD  2H 2H  2e  NAD H HH Oxidation + + + +

21. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings NADH passes electrons –To an electron transport chain As electrons “fall” from carrier to carrier and finally to O 2 –Energy is released in small quantities H2OH2O NAD  NADH ATP HH HH Controlled release of energy for synthesis of ATP Electron transport chain 2 O2O2 2e   1 2 6.6 Redox reactions release energy when electrons “fall” from a hydrogen carrier to oxygen Figure 6.5C

22. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings NADH delivers its electrons to an electron carrier (blue balls in diagram below) –Releasing energy with each transfer These reactions in series are called –Electron Transport Chains  these reactions release H20 as a waste product

23. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings In chemiosmosis –cells use the energy in concentration gradients to generate ATP using protein complexes called ATP Synthases 6.7 Two mechanisms generate ATP

24. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings In substrate-level phosphorylation –an enzyme transfers a phosphate molecule to ADP (Adenosine Diphosphate) Enzyme Adenosine Organic molecule (substrate) ADP ATP P P P P P Figure 6.7B

25. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings STAGES OF CELLULAR RESPIRATION AND FERMENTATION 6.8 Overview: Cellular respiration occurs in three main stages Cellular respiration – Occurs in three main stages

26. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings Stage 1: Glycolysis –Occurs in the cytoplasm –Breaks down glucose into pyruvate, producing a small amount of ATP

27. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings Stage 2: The citric acid cycle (Kreb’s Cycle) –Takes place in the mitochondria –Completes the breakdown of glucose, producing a small amount of ATP –Supplies the third stage of cellular respiration with electrons

28. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings Stage 3: Oxidative phosphorylation –Occurs in the mitochondria –Uses the energy released by “falling” electrons to pump H + across a membrane –Harnesses the energy of the H + gradient through chemiosmosis, producing ATP

29. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings An overview of cellular respiration NADH FADH 2 GLYCOLYSIS Glucose Pyruvate CITRIC ACID CYCLE OXIDATIVE PHOSPHORYLATION (Electron Transport and Chemiosmosis) Substrate-level phosphorylation Oxidative phosphorylation Mitochondrion and High-energy electrons carried by NADH ATP CO 2 Cytoplasm Substrate-level phosphorylation Figure 6.6

30. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings 6.9 Glycolysis harvests chemical energy by oxidizing glucose to pyruvate In glycolysis, ATP is used to prime a glucose molecule –Which is split into two molecules of pyruvate NAD  NADH HH Glucose 2 Pyruvate ATP 2 P 2 ADP 2 2 2 2 + + Figure 6.7A

31. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings Glycolysis produces ATP by substrate-level phosphorylation –In which a phosphate group is transferred from an organic molecule to ADP Enzyme Adenosine Organic molecule (substrate) ADP ATP P P P P P Figure 6.7B

32. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings In the first phase of glycolysis –ATP is used to energize a glucose molecule, which is then split in two ATP Glucose PREPARATORY PHASE (energy investment) ADP Step Glucose-6-phosphate Fructose-6-phosphate P P Fructose-1,6-diphosphate ATP ADP P P Steps – A fuel molecule is energized, using ATP. Step A six-carbon intermediate splits into two three-carbon intermediates. 1 2 3 4 4 13 Figure 6.7C

33. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings Pyruvate ATP ADP ATP ADP P ATP ADP P 2-Phosphoglycerate P H2OH2O H2OH2O Phosphoenolpyruvate (PEP) Steps – ATP and pyruvate are produced. P 3 -Phosphoglycerate P P 99 6 6 7 7 8 8 6 9 Step A redox reaction generates NADH. P NADH P P P PP P +H  ENERGY PAYOFF PHASE Glyceraldehyde-3-phosphate (G3P) 1,3 -Diphosphoglycerate P 5 6 9 55 66 77 88 99 NAD   In the second phase of glycolysis –ATP, NADH, and pyruvate are formed Figure 6.7C

34. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings CO 2 Pyruvate NAD  NADH  H  CoA Acetyl CoA (acetyl coenzyme A) Coenzyme A Figure 6.8 6.10 Pyruvate is chemically groomed for the citric acid cycle Prior to the citric acid cycle –Enzymes process pyruvate, releasing CO 2 and producing NADH and acetyl CoA 1 2 3

35. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings 6.9 The citric acid cycle completes the oxidation of organic fuel, generating many NADH and FADH 2 molecules In the citric acid cycle –The two-carbon acetyl part of acetyl CoA is oxidized CoA CO 2 NAD  NADH FAD FADH 2 ATPP CITRIC ACID CYCLE ADP  3 3  3 H  Acetyl CoA 2 Figure 6.9A

36. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings The two carbons are added to a four-carbon compound, forming citrate –Which is then degraded back to the starting compound

37. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings and Stepsand CITRIC ACID CYCLE Oxaloacetate CoA 2 carbons enter cycle Acetyl CoA Citrate leaves cycle  H H NAD  NADH CO 2 Alpha-ketoglutarate leaves cycleCO 2 ADP P NAD  NADH  H  ATP  Succinate FAD FADH 2 Malate  H  NAD  NADH Step Acetyl CoA stokes the furnace. Steps NADH, ATP, and CO 2 are generated during redox reactions. Redox reactions generate FADH 2 and NADH. Figure 6.9B For each turn of the cycle –Two CO 2 molecules are released –The energy yield is one ATP, three NADH, and one FADH 2 2 2 1 1 3 3 4 4 5 5

38. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings and Stepsand CITRIC ACID CYCLE Oxaloacetate CoA 2 carbons enter cycle Acetyl CoA Citrate leaves cycle  H H NAD  NADH CO 2 Alpha-ketoglutarate leaves cycleCO 2 ADP P NAD  NADH  H  ATP  Succinate FAD FADH 2 Malate  H  NAD  NADH Step Acetyl CoA stokes the furnace. Steps NADH, ATP, and CO 2 are generated during redox reactions. Redox reactions generate FADH 2 and NADH. Figure 6.9B 2 2 1 1 3 3 4 4 5 5

39. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings 2/2/11 – “A” Day Objective: To understand how eukaryotic cells harvest energy Do Now: What steps follow glycolysis in cell respiration? What are the products?

40. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings 2/8/11 – “E” Day Objective: To understand how eukaryotic cells harvest energy Do Now: How do cells obtain energy in the absence of oxygen?

41. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings 2/9/11 – “F” Day Objective: To understand how eukaryotic cells harvest energy Do Now: What are the two types of cellular respiration? Explain each. Today: 1.Discuss/Hand-in Mitochondrial Disease Article 2.Cellular Respiration Lab – Design Diagram – 2 DV’s HW - Complete Yeast Lab Announcements: 1.PJAS Competition 2.Science Movie Night - 2/14 in D22!

42. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings 2/10/11 – “A” Day Objective: To understand how eukaryotic cells harvest energy Do Now: What are the two types of anaerobic cellular respiration? Describe each. Today: 1.Turn in Yeast Lab! 2.Review Activity Announcements: 1.PJAS Competition 2.Science Movie Night - 2/14 in D22!

43. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings 2/11/11 – “B” Day Objective: To understand how eukaryotic cells harvest energy Do Now: Put Everything Away – Get started on your test! Today: 1.Test Announcements: 1.PJAS Competition 2.Science Movie Night - 2/14 in Audion!

44. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings 6.10 Most ATP production occurs by oxidative phosphorylation Electrons from NADH and FADH 2 –Travel down the electron transport chain to oxygen, which picks up H + to form water Energy released by the redox reactions –Is used to pump H + into the space between the mitochondrial membranes

45. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings In chemiosmosis, the H + diffuses back through the inner membrane through ATP synthase complexes –Driving the synthesis of ATP Intermembrane space Inner mitochondrial membrane Mitochondrial matrix Protein complex Electron flow Electron carrier NADH NAD + FADH 2 FAD H2OH2O ATP ADP ATP synthase 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+  P O2O2 Electron Transport Chain Chemiosmosis. OXIDATIVE PHOSPHORYLATION + 2+ 2 1 2 Figure 6.10

46. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings CONNECTION 6.11 Certain poisons interrupt critical events in cellular respiration Various poisons –Block the movement of electrons –Block the flow of H + through ATP synthase –Allow H + to leak through the membrane 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+ O2O2 H2OH2O P ATP NADHNAD + FADH 2 FAD Rotenone Cyanide, carbon monoxide Oligomycin DNP ATP Synthase  2 ADP  Electron Transport Chain Chemiosmosis 1 2 Figure 6.11

47. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings 6.12 Review: Each molecule of glucose yields many molecules of ATP Oxidative phosphorylation, using electron transport and chemiosmosis –Produces up to 38 ATP molecules for each glucose molecule that enters cellular respiration NADH FADH 2 Cytoplasm Electron shuttle across membrane Mitochondrion GLYCOLYSIS Glucose Pyruvate by substrate-level phosphorylation by oxidative phosphorylation OXIDATIVE PHOSPHORYLATION (Electron Transport and Chemiosmosis) 2 Acetyl CoA CITRIC ACID CYCLE  2 ATP  about 34 ATP Maximum per glucose: About 38 ATP 2 26 2 2 2 (or 2 FADH 2 ) Figure 6.12

48. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings 6.13 Fermentation is an anaerobic alternative to cellular respiration Under anaerobic conditions, many kinds of cells –Can use glycolysis alone to produce small amounts of ATP

49. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings In lactic acid fermentation –NADH is oxidized to NAD + as pyruvate is reduced to lactate 2 Lactate NAD  NADH NAD  222 2 2 ATP 2 ADP  2 2 Pyruvate GLYCOLYSIS P Glucose Figure 6.13A

50. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings In alcohol fermentation –NADH is oxidized to NAD + while converting pyruvate to CO 2 and ethanol NAD  NADH NAD  22 2 2 GLYCOLYSIS 2 ADP  2 P ATP Glucose 2 Pyruvate released CO 2 2 Ethanol 2 2 Figure 6.13B Figure 6.13C

51. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings INTERCONNECTIONS BETWEEN MOLECULAR BREAKDOWN AND SYNTHESIS 6.14 Cells use many kinds of organic molecules as fuel for cellular respiration

52. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings Carbohydrates, fats, and proteins can all fuel cellular respiration –When they are converted to molecules that enter glycolysis or the citric acid cycle OXIDATIVE PHOSPHORYLATION (Electron Transport and Chemiosmosis) Food, such as peanuts CarbohydratesFatsProteins Sugars Glycerol Fatty acids Amino acids Amino groups GlucoseG3P Pyruvate Acetyl CoA CITRIC ACID CYCLE ATP GLYCOLYSIS Figure 6.14

53. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings 6.15 Food molecules provide raw materials for biosynthesis Cells use some food molecules and intermediates from glycolysis and the citric acid cycle as raw materials This process of biosynthesis –Consumes ATP ATP needed to drive biosynthesis ATP CITRIC ACID CYCLE GLUCOSE SYNTHESIS Acetyl CoA PyruvateG3P Glucose Amino groups Amino acids Fatty acids Glycerol Sugars Carbohydrates FatsProteins Cells, tissues, organisms Figure 6.15

54. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings 6.16 The fuel for respiration ultimately comes from photosynthesis All organisms –Can harvest energy from organic molecules Plants, but not animals –Can also make these molecules from inorganic sources by the process of photosynthesis Figure 6.16