Microbiology 555 Metabolism – Flashcards

1) Which of the following compounds is not an enzyme? A) Dehydrogenase B) Cellulase C) Coenzyme A D) β-galactosidase E) None of the above

3) Which organism is not correctly matched to its energy source? A) Photoheterotroph light B) Photoautotroph CO2 C) Chemoautotroph Fe2+ D) Chemoheterotroph glucose E) Chemoautotroph NH3

4) How many molecules of ATP can be generated from the complete oxidation of glucose to CO 2 and H2O? A) 2 B) 4 C) 34 D) 38 E) 76

5) Which of the following is not true about anaerobic respiration? A) It involves glycolysis only. B) It involves the Krebs cycle. C) It involves the reduction of nitrate. D) It generates ATP. E) It requires cytochromes.

7) What is the fate of pyruvic acid in an organism that uses aerobic respiration? A) It is reduced to lactic acid. B) It is oxidized in the Krebs cycle. C) It is oxidized in the electron transport chain. D) It is catabolized in glycolysis. E) It is reduced in the Krebs cycle.

10) Fatty acids are catabolized in A) The Krebs cycle. B) The electron transport chain. C) Glycolysis. D) The pentose phosphate pathway. E) The Entner Doudoroff pathway.

12) According to the chemiosmotic mechanism, ATP is generated when A) Electrons are transferred between carrier molecules. B) A high-energy phosphate group is transferred from an intermediate metabolite to ADP. C) Chlorophyll liberates an electron. D) Protons are moved across a membrane. E) Cells lyse in a hypotonic environment.

13) Which of the following is the best definition of oxidative phosphorylation? A) Electrons are passed through a series of carriers to O2. B) The energy released as carrier molecules are oxidized is used to generate ATP. C) The energy released in the reduction of carrier molecules is used to generate ATP. D) The transfer of a high-energy phosphate group to ADP.

14) All the following are true about substrate-level phosphorylation except A) It involves the direct transfer of a high-energy phosphate group from an intermediate metabolic compound to ADP. B) No final electron acceptor is required. C) It occurs in glycolysis. D) The oxidation of intermediate metabolic compounds releases energy that is used to generate ATP. E) All of the above are true.

15) Which of the following is not true about photophosphorylation? A) Light liberates an electron from chlorophyll. B) The oxidation of carrier molecules releases energy. C) Energy from oxidation reactions is used to generate ATP from ADP. D) It requires CO2. E) It occurs in photosynthesizing cells.

16) Which of the following is not an end-product of fermentation? A) Lactic acid B) Ethyl alcohol C) Glycerol D) Pyruvic acid E) Acetone

17) A strictly fermentative bacterium produces energy A) By glycolysis only. B) By aerobic respiration only. C) By fermentation or aerobic respiration. D) Only in the absence of oxygen. E) Only in the presence of oxygen.

18) The advantage of the pentose phosphate pathway is that it produces all of the following except A) Precursors for nucleic acids. B) Precursors for the synthesis of glucose. C) Three ATPs. D) NADPH. E) Precursors for the synthesis of amino acids.

19) What percent of the total ATP produced from the complete catabolism of glucose is produced by aerobic respiration? A) 5% B) 11% C) 50% D) 89% E) 95%

20) Which of the following is not true about beta oxidation? A) It is a method of catabolizing fatty acids. B) It involves the formation of 2-carbon units. C) It involves the formation of acetyl-CoA. D) It is a step in glycolysis. E) None of the above.

21) In noncyclic photophosphorylation, O2 is produced from A) CO 2 B) H2 O C) C6 H12O6 D) Sunlight E) Chlorophyll

22) Which of the following is the best definition of fermentation? A) The reduction of glucose to pyruvic acid. B) The oxidation of glucose with organic molecules serving as electron acceptors. C) The complete catabolism of glucose to CO 2 and H 2O. D) The production of energy by substrate-level phosphorylation. E) The production of ethyl alcohol from glucose.

23) Which of the following is not necessary for respiration? A) Cytochromes B) Flavoproteins C) A source of electrons D) Oxygen E) Quinones

24) Aerobic respiration differs from anaerobic respiration in which of the following respects? A) Anaerobic respiration is glycolysis. B) The final electron acceptors are different. C) Aerobic respiration requires the electron transport chain. D) Aerobic respiration gets electrons from the Krebs cycle. E) Aerobic respiration produces more ATP.

25) Which one of the following would you predict is an allosteric inhibitor of the Krebs cycle enzyme, ketoglutarate dehydrogenase? A) Citric acid B) α-ketoglutaric acid C) NAD+ D) NADH E) All of the above

26) In green and purple bacteria, electrons to reduce CO 2 come from A) CO 2 B) H2 O C) C6 H12O6 D) Sunlight E) Chlorophyll

27) Assume you are growing bacteria on a lipid medium that started at pH 7. The action of bacterial lipases should cause the pH of the medium to A) Increase. B) Decrease. C) Stay the same.

28) Uses CO2 for carbon and H2 for energy. A) Chemoautotroph B) Chemoheterotroph C) Photoautotroph D) Photoheterotroph E) None of the above

29) Uses glucose for carbon and energy. A) Chemoautotroph B) Chemoheterotroph C) Photoautotroph D) Photoheterotroph E) None of the above

30) Has bacteriochlorophylls and uses alcohols for carbon. A) Chemoautotroph B) Chemoheterotroph C) Photoautotroph D) Photoheterotroph E) None of the above

31) Cyanobacteria are an example of this type. A) Chemoautotroph B) Chemoheterotroph C) Photoautotroph D) Photoheterotroph E) None of the above

32) Which statements are true? 1Electron carriers are located at ribosomes. 2ATP is a common intermediate between catabolic and anabolic pathways. 3ATP is used for the long-term storage of energy and so is often found in storage granules. 4Anaerobic organisms are capable of respiration. 5ATP is generated by the flow of protons across the cell membrane. A) 2, 4, 5 B) 1, 3, 4 C) 2, 3, 5 D) 1, 2, 3 E) All

Acetobacter 33) C2H5OHC2H3OOH -->Ethyl alcoholAcetic acid A) This process requires O2. B) This process occurs anaerobically.

4) C5H12O6 +Glucose Saccharomyces -->2C2H5OH + 2CO2 Ethyl alcohol A) This process requires O2. B) This process occurs anaerobically.

35) NO3 - + 2H + Nitrate ion Pseudomonas--> NO2- + H2O + Nitrite ion A) This process requires O2. B) This process occurs anaerobically.

36) 2H+ Hydrogen ions (E. coli) -> H2O Water A) This process requires O2. B) This process occurs anaerobically.

37) Assume you are working for a chemical company and you are responsible for growing a yeast culture that produces ethyl alcohol. The yeasts are growing well on the maltose medium but are not producing alcohol. The most likely explanation is A) The maltose is toxic. B) O2 is in the medium. C) Not enough protein is provided. D) Yeasts donʹt produce ethyl alcohol. E) None of the above.

39) An enzyme, citrate synthase, in the Krebs cycle is inhibited by ATP; this is an example of all of the following except A) Allosteric inhibition. B) Competitive inhibition. C) Feedback inhibition. D) Noncompetitive inhibition. E) None of the above.

40) A shipping company employee notices that the inside of shipsʹ hulls where ballast water is stored are deteriorating. The hull paint contained cyanide to prevent microbial growth. Since bacteria were growing on the hulls, you can conclude that the A) Bacteria were using aerobic respiration. B) Bacteria were using anaerobic respiration. C) Bacteria were growing by fermentation. D) Bacteria were using cytochromes. E) None of the above.

41) Beggiatoa bacteria get energy by oxidizing S 2- to S6+ . This means they take __(1)__ for their __(2)__. A) 1-electrons; 2-electron transport chain B) 1-electrons; 2-fermentation C) 1-protons; 2-NAD+ D) 1-sulfur; 2-photophosphorylation E) 1-glucose; 2-glycolysis

43) A bacterial culture grown in a glucose-peptide medium causes the pH to increase. The bacteria are most likely A) Fermenting the glucose. B) Oxidizing the glucose. C) Using the peptides. D) Not growing.

44) Gallionella bacteria can get energy from the reaction: Fe 2+ → Fe3+. This reaction is an example of A) Oxidation. B) Reduction. C) Fermentation. D) Photophosphorylation. E) The Calvin-Benson cycle.

45) When oxygen is unavailable, Halobacterium produce ATP by A) Fermentation. B) Photophosphorylation. C) Oxidative phosphorylation. D) Substrate-level phosphorylation. E) The Krebs cycle.