MULTIPLE CHOICE QUESTIONS 1. Which of the following statements concerning anabolic reactions is FALSE? A. They are generally endergonic. B. They usually require ATP. C. They are part of metabolism. D. They may produce polysaccharides from monosaccharides. E. They may split complex molecules into their components. 2. Aerobic respiration, anaerobic respiration, and fermentation: A. are endergonic pathways. B. release free energy. C. require oxygen. D. are also known as organismic respiration. E. are anabolic pathways. 3. Cellular respiration is most accurately described as a(n) process. A. anabolic B. catabolic C. metabolic D. endergonic E. fermentative 4. Select the anaerobic pathway. A. aerobic respiration B. citric acid cycle C. electron transport chain D. fermentation E. chemiosmosis 5. The overall reaction for the aerobic respiration of glucose is summarized as: A. C 6 H 12 O 6 + 6 O 2 + 6 H 2 O 6 CO 2 + 12 H 2 O + Energy. B. C 4 H 12 O 4 + 12 H 2 O + 6 CO 2 6 O 2 + ATP + Energy. C. C 4 H 12 O 4 + 6 O 2 + 6 H 2 O 6 CO 2 + ATP + Energy. D. C 4 H 12 O 2 + 6 O 2 + ATP 6 CO 2 + 12 H 2 O + Energy. E. C 6 H 12 O 6 + 6 H 2 O 6 CO 2 + 12 H 2 + Energy. 6. In aerobic respiration, glucose is completely: A. reduced to ATP. B. reduced to energy. C. oxidized to water. D. oxidized to carbon dioxide. E. oxidized and reduced simultaneously. 7. Aerobic respiration is classified as: A. a synthesis reaction. B. a hydrolysis reaction. C. a redox process. D. a polymerization reaction. E. an anabolic process. 8-1
8. The transfer of electrons from glucose to oxygen during aerobic respiration takes place in a stepwise fashion through a number of intermediates rather than by direct transfer. This is because: A. it is chemically impossible to transfer electrons directly from glucose to oxygen. B. the chemical intermediates donate some of their electrons in order to increase the electron pool. C. the energy of the electrons can be used to make ADP. D. the energy of the electrons can be used to make ATP. E. the energy of the protons can be used to make ATP. 9. In aerobic respiration, the electrons associated with the hydrogen atoms in glucose are transferred to: A. carbon in a series of steps. B. oxygen in a series of steps. C. NADH in a series of steps. D. the mitochondrial membranes. E. hydrogen ions. 10. If conditions are aerobic, pyruvate flows directly into the where some of its atoms are converted next to. A. cytosol; oxaloacetate B. cytosol; ATP C. mitochondria; glucose-6-phosphate D. mitochondia; acetyl coenzyme A E. mitochondria; citrate 11. Which process does not match the products? A. electron transport and chemiosmosis ATP, H 2 O, NAD +, FAD B. citric acid cycle CO 2, NADH, FADH 2, ATP C. formation of acetyl CoA Acetyl CoA, CO 2, NADH D. glycolysis pyruvate, ATP, NADH E. All of these processes match the products. 12. Which process does not match the starting materials? A. electron transport and chemiosmosis NADH, FADH 2, O 2, ADP, P i B. glycolysis glucose, ATP, NAD +, ADP, P i C. citric acid cycle acetyl CoA, H 2 O, NAD +, FAD, ADP, P i D. formation of acetyl CoA citric acid, CO 2, NADH E. All of these processes match the starting materials. 13. During chemiosmosis, are transferred from NADH and FADH 2 to electron acceptor molecules, and the energy released is used to create a(n) gradient across the inner mitochondrial membrane. A. protons; electron B. electrons; proton C. ATP molecules; ADP molecule D. ADP molecules; ATP molecule E. water molecules; oxygen 8-2
14. NADH and FADH 2 are the products of: A. decarboxylation reactions. B. reduction reactions. C. glycolysis. D. formation of acetyl coenzyme A. E. chemiosmosis. 15. Which of the following statements concerning decarboxylation reactions is FALSE? A. They occur as part of the citric acid cycle. B. They produce CO 2 that is then exhaled via breathing. C. They involve the removal of a carboxyl group (-COOH) from a substrate. D. They are one type of general reaction that occurs during aerobic respiration. E. They involve the removal of two protons and two electrons. 16. In glycolysis, fructose-1, 6-bisphosphate splits, forming two molecules of: A. ADP. B. citric acid. C. G3P. D. glucose. E. acetyl CoA. 17. NADH is formed when NAD + accepts: A. a proton. B. a hydrogen atom. C. a pair of protons and an electron. D. a proton and a pair of electrons. E. two hydrogen atoms. 8-3
18. The chemical reaction illustrated in the figure is: A. the first step in the citric acid cycle. B. the energy producing step of glycolysis. C. fermentation. D. part of the electron transport chain. E. None of these. 19. Oxidative decarboxylation of two pyruvates yields: A. 2 glucose molecules. B. 2 ATP + 4 CO 2 + 2 NADH. C. 2 G3P. D. 2 acetyl CoA + 2 CO 2 + 2 NADH. E. 1 fructose-1, 6-bisphosphate. 20. Considering only glycolysis and the conversion of pyruvate molecules to acetyl CoA molecules, how many NADH molecules will be produced from one glucose molecule? A. one B. two C. three D. four E. five 21. During the citric acid cycle, each acetyl group entering the cycle yields: A. 1 ATP, 2 NADH, and 3 FADH 2. B. 1 ATP, 3 NADH, and 1 FADH 2. C. 3 ATP, 2 NADH, and 1 FADH 2. D. 4 ATP, 2 NADH, and 1 FADH 2. E. 1 ATP, 2 NADH, and 4 FADH 2. 22. In the citric acid cycle, two acetyl CoA molecules are metabolized to: A. 2 CO 2 + 2 ATPs + 2 NADH + 2 FADH. B. 4 CO 2 + 6 NADH + 2 FADH 2 + 2 ATP. C. fructose-1, 6-bisphosphate. D. glucose + 2 CO 2 + 2 NADH + 2 FADH 2 + 2 ATPs. E. 2 G3P. 23. A glucose molecule that is metabolized via aerobic respiration has been completely broken down and released as CO 2 by the end of: A. fermentation. B. the electron transport chain. C. glycolysis. D. ATP synthesis in the mitochondria. E. the citric acid cycle. 8-4
24. Chemiosmosis allows exergonic redox processes to drive the endergonic reaction in which: A. ADP is produced by dephosphorylation of ATP. B. glucose is produced from phosphorylation of ADP. C. G3P is produced from phosphorylation of ADP. D. ATP is produced by phosphorylation of ADP. E. pyruvate is converted to acetyl CoA. 25. Coenzyme Q: A. transfers electrons. B. oxidizes glucose. C. is the ultimate source of energy in the citric acid cycle. D. transfers phosphate to ATP. E. reduces glucose. 26. The role of the oxygen molecules required for aerobic respiration is: A. to accept the low energy electrons at the end of the electron transport chain. B. to form ATP. C. to produce CO 2. D. to store high energy electrons to pass to complex I of the electron transport chain. E. to accept electrons directly from either NADH or FADH 2. 27. During aerobic respiration, oxygen is: A. formed. B. reduced. C. oxidized. D. catabolized. E. decarboxylated. 28. Which of the following steps in the Kreb s cycle directly produces a molecule of ATP (or GTP)? A. citrate isocitrate B. isocitrate α-ketoglutarate C. succinyl CoA succinate D. succinate fumarate E. malate oxaloacetate 29. A drowning death would be most directly due to: A. The unavailability of glucose to feed into glycolysis. B. The accumulation of lactate in the muscle tissue due to anaerobic respiration. C. The breakdown of pyruvate into ethyl alcohol. D. The lack of oxygen to accept hydrogen. E. There is not sufficient information to determine which answer is correct. 30. Organismal body heat is a: A. byproduct of endergonic reactions. B. product of glucose synthesis. C. byproduct of exergonic reactions. D. product of anabolism. E. product of ATP synthesis. 8-5
31. Peter Mitchell demonstrated ATP production by aerobic bacteria by placing the bacteria in: A. an acidic environment. B. a basic environment. C. an aqueous environment. D. a buffered environment. E. None of these is correct. 32. Which of the following statements about the electron transport chain is true? A. Protons are pumped out of the mitochondria by the complexes of the electron transport chain. B. The proton gradient established during electron transport is a form of potential energy. C. The electron transport chain can be found in the mitochondria of aerobic bacteria and other cells. D. The movement of protons down a concentration gradient is an endergonic process. E. ATP synthesis associated with the electron transport chain is an example of substrate level phosphorylation. 33. When hydrogen ions (protons) are pumped across the inner mitochondrial membrane, they form a proton gradient. ATP is then formed by a process known as: A. glycolysis. B. the citric acid cycle. C. chemiosmosis. D. pyruvate synthesis. E. substrate-level phosphorylation. 34. In chemiosmosis, ATP is produced as hydrogen ions (protons) pass through: A. the outer mitochondrial membrane. B. ATP synthase. C. ATP dehydrogenase. D. ATP decarboxylase. E. a series of electron carriers. 35. Select the processes that are matched with the incorrect amount of ATP produced by that process per glucose molecule. A. glycolysis 2 ATP (net) B. citric acid cycle 4 ATP C. electron transport chain 32 ATP D. alcohol fermentation 2 ATP E. lactate fermentation 2 ATP 36. In the skeletal muscle cells of vertebrates, as many as molecules of ATP are produced from one molecule of glucose. This is less than might be expected, because electrons from NADH produced during glycolysis must be shuttled through the mitochondrial membrane at a cost. A. 2; outer B. 2; inner C. 38; inner D. 6; outer E. 36; inner 8-6
37. One important regulation point in the aerobic respiration of mammals occurs in glycolysis at the site of the enzyme phosphofructokinase, which is: A. inhibited by high levels of ATP. B. inhibited by low levels of ATP. C. inhibited by high levels of AMP. D. activated by the presence of O 2. E. activated by the introduction of glucose. 38. Deamination of amino acids in mammals yields amino groups that are converted to, which is(are) excreted, and, which is(are) converted to one of the reactants of glycolysis or the citric acid cycle. A. urea; carbon chains B. amino acids; ATP C. amino groups; ADP D. carbon chains; amino acids E. amines; ATP 39. One gram of contains more than twice the amount of energy of a gram of glucose. A. amino acids B. lipids C. ATP D. protein E. starch 40. Which of the following molecules can be used as a substrate for cellular respiration? A. glucose B. lipids C. proteins D. fatty acids E. All of these. 41. Saturated fatty acids store more energy than unsaturated fatty acids. Based on your knowledge of aerobic respiration, you draw this conclusion because saturated fatty acids: A. are more highly reduced. B. are deaminated. C. lack phosphate. D. contain more ester linkages. E. contain more ATP. 42. Anaerobic respiration differs from aerobic respiration in that anaerobic respiration: A. can utilize NO - 3 as the terminal electron acceptor. B. can utilize O 2 as the terminal electron acceptor. C. produces CO 2. D. produces ATP. E. involves an electron transport chain. 8-7
43. The production of alcohol or lactate from pyruvate during occurs as a means of regenerating from. A. aerobic respiration; NAD + ; NADH B. fermentation; NAD + ; NADH C. fermentation; NADH; NAD + D. fermentation; ADP; ATP E. aerobic respiration; ATP; ADP 44. During fermentation, the immediate fate of the electrons in NADH is that they: A. are transferred to the electron transport chain. B. are transferred to an organic molecule. C. are transferred to O 2. D. are used to make CO 2. E. are used to form H 2 O. 45. If yeasts are grown under anaerobic conditions, pyruvate is converted first to and then to. A. citrate; oxaloacetate B. acetyl coenzyme A; citrate C. lactate; carbon dioxide D. acetaldehyde; ethyl alcohol E. acetaldehyde; lactate 46. Select the molecule that contains the most stored chemical energy: A. ethyl alcohol. B. water. C. carbon dioxide. D. lactate. E. oxygen. 47. Select the molecule that contains the least stored chemical energy: A. ethyl alcohol. B. pyruvate. C. glucose. D. lactate. E. oxygen. 48. The ability of some bacteria to produce lactate is exploited by humans to make: A. cheese and ethyl alcohol. B. insulin and antibodies. C. yogurt and sauerkraut. D. ethyl alcohol and carbonic acid. E. carbon dioxide and water. 49. Which of the following statements is not correct about lactic acid fermentation? A. It is inefficient compared to aerobic respiration. B. It uses glucose as a substrate. C. It produces two ATP molecules for every glucose molecule. D. Oxygen is the final electron acceptor of this pathway. E. Glycolysis is the only energy-yielding step of this pathway. 8-8
DISCUSSION OR THOUGHT QUESTION 1. What is the major difference between substrate-level phosphorylation and oxidative phosphorylation? 8-9