Question 1

Which feature of anaerobic and aerobic respiration is different between the two catabolic strategies?

Accepted Answer

A)  electron donor 
B)  electron acceptor 
C)  use of electron transport 
D)  use of proton motive force 
A)  electron donor 
B)  electron acceptor 
C)  use of electron transport 
D)  use of proton motive force B

Question 2

When culturing a chemoorganoheterophic bacterium,what outcome is LEAST likely to occur if ammonia and phosphate are provided at equal concentrations?

Accepted Answer

A)  Cells require much less P to grow than N, so extra P will be used for ATP synthesis and result in a faster growth rate. 
B)  Cells will never consume all of the phosphate, because N is needed in higher quantities than P. 
C)  The final biomass of cells will be no different than if only 50% of the phosphate was provided. 
D)  The bacteria will import all of the ammonia to use for biosynthetic pathways. 
A)  Cells require much less P to grow than N, so extra P will be used for ATP synthesis and result in a faster growth rate. 
B)  Cells will never consume all of the phosphate, because N is needed in higher quantities than P. 
C)  The final biomass of cells will be no different than if only 50% of the phosphate was provided. 
D)  The bacteria will import all of the ammonia to use for biosynthetic pathways. A

Question 3

For a carbon source,chemoorganotrophs generally use compounds such as

Accepted Answer

A)  acetate, succinate, and glucose. 
B)  bicarbonate and carbon dioxide. 
C)  nitrate and nitrite. 
D)  acetate, bicarbonate, and nitrate. 
A)  acetate, succinate, and glucose. 
B)  bicarbonate and carbon dioxide. 
C)  nitrate and nitrite. 
D)  acetate, bicarbonate, and nitrate. A

Question 4

Improperly functioning acyl carrier proteins (ACPs)would likely result in

Accepted Answer

A)  a physiological shift to anaerobic metabolism where an energized membrane is less important for energy production. 
B)  enhanced growth of a bacterium due to faster growth substrate uptake by a weakened membrane. 
C)  no harm to bacteria, because only archaeons and eukaryotes use ACPs for fatty acid biosynthesis. 
D)  death for a bacterium due to poor lipid bilayer integrity. 
A)  a physiological shift to anaerobic metabolism where an energized membrane is less important for energy production. 
B)  enhanced growth of a bacterium due to faster growth substrate uptake by a weakened membrane. 
C)  no harm to bacteria, because only archaeons and eukaryotes use ACPs for fatty acid biosynthesis. 
D)  death for a bacterium due to poor lipid bilayer integrity.

Question 5

The change in Gibbs free energy for a particular reaction is MOST useful in determining

Accepted Answer

A)  the amount of energy catalysts required for biosynthesis or catabolism. 
B)  the potential metabolic reaction rate. 
C)  whether there will be a requirement or production of energy. 
D)  energy stored in each compound. 
A)  the amount of energy catalysts required for biosynthesis or catabolism. 
B)  the potential metabolic reaction rate. 
C)  whether there will be a requirement or production of energy. 
D)  energy stored in each compound.

Question 6

Depending on the particular metabolism of a bacterium,electron transport can be used to energize and rotate ATP synthase.

Accepted Answer

A) True 
 B)False

Question 7

The rising of bread dough is the result of

Accepted Answer

A)  biotin production. 
B)  carbon dioxide produced by fermentation. 
C)  oxidative phosphorylation. 
D)  oxygen being released. 
A)  biotin production. 
B)  carbon dioxide produced by fermentation. 
C)  oxidative phosphorylation. 
D)  oxygen being released.

Question 8

Fermentation has a relatively low ATP yield compared to aerobic respiration because

Accepted Answer

A)  more reducing equivalents are used for anaerobic catabolism. 
B)  less ATP is consumed during the first stage of aerobic catabolism. 
C)  oxidative phosphorylation yields a lot of ATP. 
D)  substrate-level phosphorylation yields a lot of ATP. 
A)  more reducing equivalents are used for anaerobic catabolism. 
B)  less ATP is consumed during the first stage of aerobic catabolism. 
C)  oxidative phosphorylation yields a lot of ATP. 
D)  substrate-level phosphorylation yields a lot of ATP.

Question 9

Explain why the amount of energy released in a redox reaction depends on the nature of both the electron donor and the electron acceptor.

Accepted Answer

Answers should emphasize that energy doe

Question 10

If an oxidation reaction occurs

Accepted Answer

A)  simultaneous reduction of a different compound will also occur, because electrons do not generally exist alone in solution. 
B)  another oxidation reaction will occur for a complete reaction, because one oxidation event is considered a half reaction. 
C)  a cell is undergoing aerobic respiration, because oxygen is being used. 
D)  a reduction reaction would not occur, because they are opposite reaction mechanisms. 
A)  simultaneous reduction of a different compound will also occur, because electrons do not generally exist alone in solution. 
B)  another oxidation reaction will occur for a complete reaction, because one oxidation event is considered a half reaction. 
C)  a cell is undergoing aerobic respiration, because oxygen is being used. 
D)  a reduction reaction would not occur, because they are opposite reaction mechanisms.

Question 11

Catabolic pathways are essential for microorganisms to obtain energy,because biosynthetic reactions for cellular growth generally require energy input.

Accepted Answer

A) True 
 B)False

Question 12

A bacterium running low on NADPH could ________ to generate more of this coenzyme.

Accepted Answer

A)  degrade an amino acid or nucleic acid 
B)  invoke the pentose phosphate pathway 
C)  degrade a fatty acid 
D)  use a broad specificity phosphatase with inorganic phosphatase and NADH 
A)  degrade an amino acid or nucleic acid 
B)  invoke the pentose phosphate pathway 
C)  degrade a fatty acid 
D)  use a broad specificity phosphatase with inorganic phosphatase and NADH

Question 13

With respect to nitrogen utilization,relatively few bacteria can use NH₃ whereas many more can make use of N₂.

Accepted Answer

A) True 
 B)False

Question 14

Explain the biosynthetic and bioenergetic roles of the citric acid cycle.

Accepted Answer

Some of the molecules generated during t

Question 15

A chemoorganotroph and a photoautotroph in the same environment would NOT compete for

Accepted Answer

A)  oxygen. 
B)  carbon. 
C)  nitrogen. 
D)  carbon and oxygen. 
A)  oxygen. 
B)  carbon. 
C)  nitrogen. 
D)  carbon and oxygen.

Question 16

What is the difference between a coenzyme and a prosthetic group?

Accepted Answer

A)  Coenzymes are essential for an enzyme's function and prosthetic groups only enhance its reaction rate. 
B)  Coenzymes are weakly bound whereas prosthetic groups are strongly bound to their respective enzymes. 
C)  Coenzymes are organic cofactors and prosthetic groups are inorganic cofactors. 
D)  Coenzymes require additional ions to bind to enzymes but prosthetic groups are able to directly interact with enzymes. 
A)  Coenzymes are essential for an enzyme's function and prosthetic groups only enhance its reaction rate. 
B)  Coenzymes are weakly bound whereas prosthetic groups are strongly bound to their respective enzymes. 
C)  Coenzymes are organic cofactors and prosthetic groups are inorganic cofactors. 
D)  Coenzymes require additional ions to bind to enzymes but prosthetic groups are able to directly interact with enzymes.

Question 17

Explain what an enzyme must accomplish to catalyze a specific reaction.

Accepted Answer

Answers will vary,but the focu

Question 18

How does the proton motive force lead to production of ATP?

Accepted Answer

A)  ATPase requires one proton to make one ATP. 
B)  Protons must be pumped against a concentration gradient from outside of the cell into the cell to rotate the F₀ subunit of ATPase for the F₁ subunit to make ATP. 
C)  Oxidative phosphorylation of ADP by ATP synthase requires protons as cofactors in the reaction. 
D)  Translocation of three to four protons drives the F₀ component of ATPase which in turn phosphorylates one ADP into ATP. 
A)  ATPase requires one proton to make one ATP. 
B)  Protons must be pumped against a concentration gradient from outside of the cell into the cell to rotate the F₀ subunit of ATPase for the F₁ subunit to make ATP. 
C)  Oxidative phosphorylation of ADP by ATP synthase requires protons as cofactors in the reaction. 
D)  Translocation of three to four protons drives the F₀ component of ATPase which in turn phosphorylates one ADP into ATP.

Question 19

Which of the following would be used by a chemoorganotroph for energy?

Accepted Answer

A)  C₂H₃O₂⁻ 
B)  H₂ 
C)  CO₂ 
D)  H⁺ 
A)  C₂H₃O₂⁻ 
B)  H₂ 
C)  CO₂ 
D)  H⁺

Question 20

In an aquatic microbial community where a photoautotroph,chemoorganoheterotroph,and nitrogen fixing bacterium are present,predict an environmental perturbation that would cause only one to be outcompeted by the other two groups and explain how each group would respond.

Accepted Answer

Answers will vary but should highlight a

Exam 3: Microbial Metabolism

Which feature of anaerobic and aerobic respiration is different between the two catabolic strategies?

When culturing a chemoorganoheterophic bacterium,what outcome is LEAST likely to occur if ammonia and phosphate are provided at equal concentrations?

For a carbon source,chemoorganotrophs generally use compounds such as

Improperly functioning acyl carrier proteins (ACPs)would likely result in

The change in Gibbs free energy for a particular reaction is MOST useful in determining

Depending on the particular metabolism of a bacterium,electron transport can be used to energize and rotate ATP synthase.

The rising of bread dough is the result of

Fermentation has a relatively low ATP yield compared to aerobic respiration because

Explain why the amount of energy released in a redox reaction depends on the nature of both the electron donor and the electron acceptor.

If an oxidation reaction occurs

Catabolic pathways are essential for microorganisms to obtain energy,because biosynthetic reactions for cellular growth generally require energy input.

A bacterium running low on NADPH could ________ to generate more of this coenzyme.

With respect to nitrogen utilization,relatively few bacteria can use NH₃ whereas many more can make use of N₂.

Explain the biosynthetic and bioenergetic roles of the citric acid cycle.

A chemoorganotroph and a photoautotroph in the same environment would NOT compete for

What is the difference between a coenzyme and a prosthetic group?

Explain what an enzyme must accomplish to catalyze a specific reaction.

How does the proton motive force lead to production of ATP?

Which of the following would be used by a chemoorganotroph for energy?

In an aquatic microbial community where a photoautotroph,chemoorganoheterotroph,and nitrogen fixing bacterium are present,predict an environmental perturbation that would cause only one to be outcompeted by the other two groups and explain how each group would respond.

Microorganisms and Microbiology

Microbial Cell Structure and Function

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Metabolic Regulation

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Genetics of Bacteria and Archaea

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Metabolic Diversity of Microorganisms

Functional Diversity of Bacteria

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Diversity of Eukaryotic Microorganisms

Methods in Microbial Ecology

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Nutrient Cycles

Microbiology of the Built Environment

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Microbial Interactions With Humans

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Immune Mechanisms

Molecular Immunology

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Vectorborne and Soilborne Bacterial and Viral Diseases

Water and Food As Vehicles of Bacterial Diseases

Eukaryotic Pathogens: Fungal and Parasitic Diseases

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