Name______________________________________________________________Period__________Date__________________________

Cellular Respiration Homework and Study Guide Directions: Below you will find a variety of questions on cellular respiration. As you will soon notice, the

questions are of varying formats. For short answer questions, please write in complete sentences. For true/false questions, first determine if the statement is true or false. If the statement is false, correct the underlined word to make the statement true. As we cover this material on cellular respiration, you will be assigned some of these questions each night. When this assignment is complete, you will have a great study guide for the unit test.

1. What is cellular respiration?

2. ________________True or False. Food serves as a source of energy by being a fuel for cellular respiration, as well as by supplying the raw materials needed for the building of new molecules within a cell.

3. ________________True or False. The difference between ADP and ATP is that ADP has three phosphate molecules.

4. ________________True or False. The energy that flows through the ecosystem cannot be recycled. 5. ________________True or False. The chemical elements essential for life cannot be recycled. 6. Briefly describe the relationship between photosynthesis and respiration.

7. __________________________ Which organisms perform photosynthesis?

8. __________________________ Which organisms perform cellular respiration?

9. __________________________ What are the reactants of photosynthesis?

10. __________________________ What are the products of photosynthesis?

11. __________________________ What are the reactants of cellular respiration?

12. __________________________ What are the products of respiration?

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13. In which of the following ways is photosynthesis similar to respiration? a. Both processes produce ATP. b. Both processes produce ATP by generating energy from an electron transport chain to pump

hydrogen protons to an area of higher concentration. c. Both use ATP synthases to generate ATP. d. Both processes produce PGAL. e. Both processes involve energy transformations. f. All of the above are correct.

14. Energy flows through living systems from:

a. the sun to heterotrophs and then to autotrophs b. autotrophs to the environment and then to heterotrophs c. the sun to autotrophs and then to heterotrophs d. the environment to heterotrophs and then to autotrophs.

15. What is the equation for cellular respiration?

16. Compare and contrast the following pairs of terms: anaerobic and aerobic respiration.

17. List the stages of cellular respiration and indicate whether each is anaerobic or aerobic and where the stage occurs.

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18. Use the diagram of a mitochondrion to: a. Label the following: outer membrane, inner

membrane, cristae, matrix and cytoplasm. b. Indicate where each stage of respiration (glycolysis,

Krebs cycle, electron transport chain) occurs.

The diagram to the right shows the steps of glycolysis.

19. The first step in releasing the energy that is stored in molecules of glucose is known as: a. fermentation b. glycolysis c. the bridge reactions d. electron transport e. aerobic respiration.

20. ________________ True or False. Even though cellular respiration is

an energy releasing process, the cell must invest a small amount of energy to get the reaction going.

21. ________________ True or False. The hydrogen electron acceptor during glycolysis is FAD.

22. ________________ Glycolysis begins with what 6-carbon molecule?

23. ________________ What 3-carbon molecules are produced at the end of glycolysis?

24. ________ The number of ATP used during glycolysis? 25. ________ The number of ATP produced during glycolysis? 26. ________ The net gain of ATP during glycolysis? 27. What is the purpose of the electron acceptor, NAD+? 28. What will now happen to the pyruvate that glycolysis has created? 29. ________________ True or False. The aerobic stages of respiration take place in the chloroplasts of

the cell. 30. ________________ True or False. The anaerobic stages of respiration take place in the mitochondria

of the cell. 31. ________________ True or False. Only eukaryotic cells can carry out cellular respiration. 32. ________________ In what part of the mitochondria does the Krebs cycle occur?

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33. ________________ Where in the mitochondria does the electron transport chain take place? 34. ________________ Loops and folds of the inner mitochondrial membrane are called?

The diagram to the right shows the chemical reactions that occur during the Krebs cycle. 35. The following sentence describes a broad overview of the Krebs

cycle. Fill in the blanks of this sentence: Coenzyme A (CoA) attaches the 2-carbon ______________ to the 4-carbon compound to form the 6-carbon _________________.

36. Before the Krebs cycle can proceed, pyruvate must be converted

to: a. lactic acid b. oxaloacetic acid c. citric acid d. acetyl CoA e. NADH

37. For each turn of the Krebs cycle:

a. ____ How many ATP are produced? b. ____ How many NADH are produced? c. ____ How many FADH2 are produced? d. ____ How many molecules of carbon dioxide are produced?

38. For each molecule of glucose entering respiration:

a. ____ How many ATP are produced? b. ____ How many NADH are produced? c. ____ How many FADH2 are produced? d. ____ How many molecules of carbon dioxide are produced?

39. ___________________ What molecules are made during the Kreb’s cycle and are later used in the

electron transport chain? 40. ___________________ What molecule determines whether pyruvate will undergo fermentation or

be sent to the Kreb’s cycle?

41. Which of the following is not a product of the Kreb’s cycle? a. acetate b. carbon dioxide c. NADH d. FADH2 e. citric acid f. oxaloacetic acid

42. How will the NADH and the FADH2 be used?

43. What will happen to the carbon dioxide that has been produced during respiration?

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44. Use the diagram of the Electron Transport Chain to:

a. Label the following on the diagram above: mitochondrial matrix, inner membrane, inner membrane space, cristae.

b. Using the symbol, e _, show the path of electrons from their entry point to their final destination.

c. What is the final electron acceptor? What is the product it produces?

d. Label the area of high hydrogen proton concentration. Label the area of low hydrogen proton concentration. Indicate the direction of movement of hydrogen protons as the electrons move down the ETC. What type of transport would this be considered?

e. There is only one place that is permeable to the re-entry of hydrogen protons. What is the name

of this re-entry protein?

f. What happens as hydrogen protons flow from the area of high concentration to the area of low concentration?

g. What is the end result of all of this?

45. _____________________ True or False. At the end of the electron transport chain, hydrogen combines with carbon dioxide to form water.

46. _____________________ True or False. The electron transport chain consists of a series of proteins that are embedded in the inner membrane.

47. As high-energy electrons flow down the electron transport chain, energy is released. What is this

energy used to do?

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48. How are ATP produced during this final stage of respiration?

49. How is the production of ATP in the electron transport chain similar to the production of ATP during the light dependent reactions of photosynthesis?

50. Let’s summarize the production of ATP (per glucose molecule) during cellular respiration:

_______ a) How many ATP are gained during glycolysis? _______ b) How many ATP are produced during the bridge reactions? _______ c) How many ATP are produced during the Kreb’s cycle? _______ d) How many ATP are produced during the electron transport chain? _______ e) How many ATP can be produced for each NADH? _______ f) How many ATP can be produced for each FADH2? _______ g) How many ATP are gained during anaerobic respiration? _______ h) How many ATP are produced in aerobic respiration? _______ i) How many ATP are produced in the cytoplasm? _______ j) How many ATP are produced in the mitochondria?

51. What condition must exist in a cell that would cause the cell to enter into fermentation?

52. ______________________ This molecule is made during glycolysis and used in the later steps of fermentation.

53. ______________________ List the two types of fermentation.

______________________ 54. ______________________ What organism is used to carry out alcoholic fermentation for commercial

purposes? 55. ______________________ During alcoholic fermentation, pyruvate is converted into what

compound? 56. ______________________ How many ATP are gained per molecule of glucose during fermentation?

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57. How is alcoholic fermentation used in the baking industries? 58. What causes your muscles to become tired and sometimes cramp during periods of strenuous exercise?

59. The anaerobic pathways provide enough energy to meet the energy needs of which of the following? a. all living organisms b. unicellular organisms and almost all of the multicellular organisms c. only photosynthetic organisms d. no organisms e. all unicellular organisms.

60. Write equations to show how alcoholic fermentation compares to lactic acid fermentation.