1. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Cellular Respiration Chapter 7 Table of Contents Section 1 Glycolysis and Fermentation Section 2 Aerobic Respiration

2. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Glycolysis and Fermentation Chapter 7 Objectives Identify the two major steps of cellular respiration. Describe the major events in glycolysis. Compare lactic acid fermentation with alcoholic fermentation. Calculate the efficiency of glycolysis.

3. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 7 Harvesting Chemical Energy Cellular respiration is Both autotrophs and heterotrophs use cellular respiration to make The products of cellular respiration are the reactants in photosynthesis; conversely, Cellular respiration can be divided into two stages: Section 1 Glycolysis and Fermentation

4. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Stage 1 is. Organic compounds are Which produces a small Glycolysis is Chapter 7 Section 1 Glycolysis and Fermentation Harvesting Chemical Energy, continued; Stage 1

5. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu If oxygen is present in the cell’s environment, pyruvic acid is broken down and Pyruvic acid can enter other pathways if The combination of glycolysis and these Chapter 7 Section 1 Glycolysis and Fermentation Harvesting Chemical Energy, continued; Stage 2

6. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 7 Photosynthesis-Cellular Respiration Cycle Section 1 Glycolysis and Fermentation

7. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 7 Glycolysis Cellular respiration begins with glycolysis, which takes place in During glycolysis, one six-carbon glucose molecule is A net yield of Section 1 Glycolysis and Fermentation

8. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 7 Glycolysis, continued; Step 1 In step 1, 2 phosphate groups are attached to Forms a new The phosphate groups are supplied by ATP is then converted into 2 molecules of Section 1 Glycolysis and Fermentation

9. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 7 Glycolysis, continued; Step 2 In step 2, the 6-carbon compound formed from step 1 is split G3P is also Section 1 Glycolysis and Fermentation

10. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 7 Glycolysis, continued; Step 3 In step 3, the 2 G3P are Each receive a Results in 2 molecules of a Remember when something oxidized, something reduced. –2 nicotinamide adenine dinucleotide (NAD + ) to NADH NAD + is organic molecule that accepts e - during redox RXNs Section 1 Glycolysis and Fermentation

11. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 7 Glycolysis, continued; Step 4 In step 4, the phosphate groups added in steps 1 & 3 are This reaction produces 2 molecules of Each phosphate is combined with Because a total of 4 phosphate groups were added in steps 1 & 3, Section 1 Glycolysis and Fermentation

12. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 7 Glycolysis Section 1 Glycolysis and Fermentation

13. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 7 Fermentation If oxygen is not present, some cells can convert pyruvic acid into other compounds through additional biochemical pathways that occur in the cytosol. Fermentation does not produce ATP, but it does regenerate ______, which allows for the continued production of Section 1 Glycolysis and Fermentation

14. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 7 Cellular Respiration Versus Fermentation Section 1 Glycolysis and Fermentation

15. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 7 Fermentation, continued Lactic Acid Fermentation –In lactic acid fermentation, an enzyme converts ____________ _________ into another three- carbon compound, called ______________ ______________. Section 1 Glycolysis and Fermentation

16. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 7 Fermentation, continued Alcoholic Fermentation –Some plants and unicellular organisms, such as yeast, use a process called alcoholic fermentation to convert Section 1 Glycolysis and Fermentation

17. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 7 Two Types of Fermentation Section 1 Glycolysis and Fermentation

18. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Fermentation, continued Chapter 7 Section 1 Glycolysis and Fermentation

19. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Fermentation, continued Chapter 7 Section 1 Glycolysis and Fermentation

20. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 7 Fermentation, continued Through glycolysis, only about _____ percent of the energy available from the oxidation of glucose is captured as _________. Much of the energy originally contained in glucose is still held in _____________ ______________. Glycolysis alone or as part of fermentation is not very efficient at Section 1 Glycolysis and Fermentation

21. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 7 Objectives Relate aerobic respiration to the structure of a mitochondrion. Summarize the events of the Krebs cycle. Summarize the events of the electron transport chain and chemiosmosis. Calculate the efficiency of aerobic respiration. Contrast the roles of glycolysis and aerobic respiration in cellular respiration. Section 2 Aerobic Respiration

22. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Aerobic Respiration Chapter 7 Overview of Aerobic Respiration In eukaryotic cells, the processes of aerobic respiration occur in the ________________. Aerobic respiration only occurs if ______________ is present in the cell. The Krebs cycle occurs in the ________________ ___________________. The electron transport chain (which is associated with chemiosmosis) is located in

23. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Overview of Aerobic Respiration Two stages of aerobic respiration: 1. 2. In prokaryotes aerobic respiration takes place in the The mitochondrial matrix contains enzymes that Chapter 7 Section 2 Aerobic Respiration

24. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Aerobic Respiration Chapter 7 The Krebs Cycle In the mitochondrial matrix, pyruvic acid produced in glycolysis reacts with ________________ to form _____________________ Then, ____________________ enters the ________________________. One glucose molecule is completely broken down in two turns of the Krebs cycle. These two turns produce The bulk of the energy released by the oxidation of glucose still has not been

25. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu In step 1, a 2-carbon molecule of This reaction Chapter 7 Section 2 Aerobic Respiration The Krebs Cycle, continued; Step 1

26. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu In step 2, citric acid releases a By losing a hydrogen atom with its e -, The e - in the hydrogen atom is transferred to Chapter 7 Section 2 Aerobic Respiration The Krebs Cycle, continued; Step 2

27. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu In step 3, the 5- carbon compound formed in step 2 also NAD + is A molecule of ATP is Chapter 7 Section 2 Aerobic Respiration The Krebs Cycle, continued; Step 3

28. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu In step 4, the 4-carbon compound formed in step 3 releases a The hydrogen is used to FAD similar to Like NAD +, FAD accepts Chapter 7 Section 2 Aerobic Respiration The Krebs Cycle, continued; Step 4

29. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu In step 5, the 4- carbon compound formed in step 4 releases a The e - in the hydrogen reduces Chapter 7 Section 2 Aerobic Respiration The Krebs Cycle, continued; Step 5

30. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 7 Krebs Cycle Section 2 Aerobic Respiration

31. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Aerobic Respiration Chapter 7 Electron Transport Chain and Chemiosmosis High-energy electrons in hydrogen atoms from _________ and _________ are passed from molecule to molecule in the electron transport chain along the inner mitochondrial membrane.

32. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Aerobic Respiration Chapter 7 Electron Transport Chain and Chemiosmosis, continued Protons (hydrogen ions, H + ) are also given up by _______ and ___________. As the electrons move through the electron transport chain, they lose energy. This energy is used to pump The resulting high concentration of protons creates a

33. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Aerobic Respiration Chapter 7 Electron Transport Chain and Chemiosmosis, continued As protons move through ATP synthase and down their concentration and electrical gradients, ATP is produced. Oxygen combines with the electrons and protons to form water.

34. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Aerobic Respiration Chapter 7 Electron Transport Chain and Chemiosmosis, continued The Importance of Oxygen –ATP can be synthesized by chemiosmosis only if –By accepting electrons from the last molecule in the electron transport chain, oxygen allows –As a result, ATP can continue to be made through __________________.

35. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Aerobic Respiration Chapter 7 Electron Transport Chain and Chemiosmosis, continued; step 1 In step 1, NADH & NADH donates e - at the Both molecules also give up

36. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Aerobic Respiration Chapter 7 Electron Transport Chain and Chemiosmosis, continued; step 2 In step 2, the e - are passed As they move from molecule

37. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Aerobic Respiration Chapter 7 Electron Transport Chain and Chemiosmosis, continued; step 3 In step 3, the energy lost from the e - is used to pump protons from the matrix, building a A concentration gradient of protons is created across An electrical gradient is also created, as the protons carry a

38. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Aerobic Respiration Chapter 7 Electron Transport Chain and Chemiosmosis, continued; step 4 In step 4, the concentration & electrical gradients of protons drive synthesis of ATP synthase is embedded in the As protons move through ATP synthase & down their concentration & electrical gradients, ATP is

39. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Aerobic Respiration Chapter 7 Electron Transport Chain and Chemiosmosis, continued; step 5 In step 5, oxygen is the final acceptor of Oxygen also accepts protons that were a part of hydrogen supplied by The protons, electrons, &

40. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Aerobic Respiration Chapter 7 ETC

41. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Aerobic Respiration Chapter 7 Chemiosmosis

42. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Aerobic Respiration Chapter 7 Efficiency of Cellular Respiration Cellular respiration can produce up to _____ ATP molecules from the oxidation of a single molecule of glucose. Most eukaryotic cells produce about _____ ATP molecules per molecule of glucose. Thus, cellular respiration is nearly ______ times more efficient than glycolysis alone.

43. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Aerobic Respiration Chapter 7 A Summary of Cellular Respiration Another Role of Cellular Respiration –Providing cells with ATP is not the only important function of cellular respiration. –Molecules formed at different steps in glycolysis and the Krebs cycle are often used by cells to

44. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 7 Summary of Cellular Respiration Section 2 Aerobic Respiration

45. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Aerobic Respiration Chapter 7 Electron Transport Chain and Chemiosmosis