Chapter 11

12. The pentose phosphate pathway produces A. CO2. B. NADPH. C. glyceraldehyde 3-phosphate. D. All of the choices are correct.

D. All of the choices are correct.

39. Which of the following can be used as electron acceptors during anaerobic respiration? A. Nitrate B. Sulfate C. Carbon dioxide D. All of the choices are correct.

D. All of the choices are correct.

21. The major function(s) of the TCA cycle is(are) A. energy production. B. provision of carbon skeletons for biosynthesis of cell components. C. electron transport. D. energy production and provision of carbon skeletons for biosynthesis of cell components.

D. energy production and provision of carbon skeletons for biosynthesis of cell components.

15. The TCA cycle generates all of the following from each acetyl-CoA molecule oxidized except A. three NADH molecules. B. two CO2 molecules. C. one FADH2 molecule .D. two ATP or GTP molecules.

D. two ATP or GTP molecules.

3. Metabolic pathways can be either catabolic or anabolic but not both.

FALSE

42. In the process of fermentation an organic substrate, such as glucose, is reduced and an intermediate of the pathway, such as pyruvate, is oxidized.

FALSE

44. Oxygen is always required for the regeneration of NAD from NADH.

FALSE

8. Some aerobic bacteria lack the Entner-Doudoroff and Embden-Meyerhoff pathways and instead use the pentose phosphate pathway for glycolysis.

FALSE

10. The net gain of ATP per molecule of glucose metabolized anaerobically via the Embden-Meyerhof pathway in prokaryotes is A. 2. B. 36. C. 38. D. 85.

A. 2.

28. Differences between mitochondrial and E. coli electron transport chains include the following: A. The E. coli chain contains a different array of cytochromes. B. The fundamental principles on which they operate are different. C. Higher P/O values are observed in E. coli. D. The electron transport chain does not involve membranes in E. coli.

A. The E. coli chain contains a different array of cytochromes.

20. In the TCA cycle, two carbons in the form of __________ are added to oxaloacetate at the start of the cycle. A. acetyl-CoA B. ethanol C. carbon dioxide D. methanol

A. acetyl-CoA

47. Fatty acids are metabolized by the __________ pathway. A. alpha-oxidation B. beta-oxidation C. gamma-oxidation D. delta-oxidation

B. beta-oxidation

35. In aerobic conditions, it takes __________ sugar to produce the same amount of ATP when compared to anaerobic conditions. A. more B. less C. the same amount of

B. less

32. Mitochondrial electron transport takes place A. on the outer mitochondrial membrane. B. on the inner mitochondrial membrane. C. in the fluid matrix of the mitochondria. D. on the outer mitochondrial membrane and on the inner mitochondrial membrane.

B. on the inner mitochondrial membrane.

31. Production of ATP using the energy liberated when electrons from reduced chemical bonds are passed through the electron transport system is generally referred to as A. chemiosmotic. B. respiration. C. substrate-level. D. conformational change.

B. respiration.

11. The net gain of ATP per molecule of glucose metabolized to pyruvate using Entner-Doudoroff pathway is A. 4. B. 2. C. 1. D. 0.

C. 1.

30. The theoretical maximum net gain of ATP per molecule of glucose metabolized aerobically in eukaryotes is A. 2. B. 32. C. 38. D. 85.

C. 38.

14. The most common pathway for conversion of glucose to pyruvate is A. Entner-Doudoroff. B. Pentose phosphate. C. Embden-Meyerhoff. D. mixed acid fermentation.

C. Embden-Meyerhoff.

34. The number of ATP molecules generated per atom of oxygen that is reduced when electrons are passed from NADH or reduced FAD (FADH) to O2 is called the A. utilization ratio. B. energy yield. C. P/O ratio. D. phosphorylation coefficient.

C. P/O ratio.

29. Which of the following is NOT true regarding ATP synthases? A. They require proton motive force to make ATP. B. They span the inner membrane of mitochondria. C. The proton flow is outward during ATP synthesis. D. The subunits of ATP synthase undergo conformational changes during ATP production.

C. The proton flow is outward during ATP synthesis.

33. In higher eukaryotes, most aerobically generated ATP is produced by A. glycolysis. B. the TCA cycle. C. a membrane-bound proton translocating ATP synthase during oxidative phosphorylation. D. all of these generate equal amounts of ATP.

C. a membrane-bound proton translocating ATP synthase during oxidative phosphorylation.

16. The pyruvate dehydrogenase complex oxidizes and cleaves pyruvate to form one CO2 and A. lactate. B. isocitric acid. C. acetyl-CoA. D. succinyl-CoA.

C. acetyl-CoA.

19. In the TCA cycle, two carbons are removed from citric acid in the form of __________, thereby regenerating oxaloacetate to complete the cycle. A. acetyl-CoA B. ethanol C. carbon dioxide D. methanol

C. carbon dioxide

1. The sum total of all chemical reactions occurring in a cell is called A. anabolism. B. catabolism. C. metabolism. D. None of the choices are correct.

C. metabolism.

13. The synthesis of ATP from ADP and Pi, when coupled with an exergonic chemical reaction is called __________ phosphorylation. A. chemiosmotic B. oxidative C. substrate-level D. conformational change

C. substrate-level

48. During breakdown of fatty acids, carbons are removed __________ at a time with each turn of the cycle, and two carbon units are released as __________. A. one; carbon dioxide B. one; methane C. two; acetyl-CoA D. two; ethanol

C. two; acetyl-CoA

2. Although most metabolic reactions are freely reversible, a few irreversible catabolic steps are bypassed during biosynthesis with special enzymes that catalyze the reverse reaction in order to allow for independent regulation of catabolic and anabolic pathways.

TRUE

25. Bacterial electron transport chains may be comprised of fewer components and have lower P/O ratios than mitochondrial transport chains.

TRUE

26. The electron transport systems in eukaryotes and prokaryotes use different electron carriers.

TRUE

27. In addition to being used in the making of ATP, proton motive force is used directly to power the rotation of bacterial flagella.

TRUE

36. Prokaryotes may use several different terminal oxidases for the electron transport system.

TRUE

37. Reduction of nitrate to nitrite by Paracoccus denitrificans is an example of anaerobic respiration.

TRUE

41. Fermentation involves the use of pyruvate and/or other organic molecules as electron acceptors.

TRUE

5. The catabolism of glucose begins with one or more of the glycolytic pathways that yield pyruvate.

TRUE

7. Very few Gram-positive bacteria utilize the Entner-Doudoroff glycolytic pathway.

TRUE

9. An organism may use glycolysis and the pentose phosphate pathway simultaneously.

TRUE