Question 1

Methanogens that use methyl-CoM for biosynthesis use ________ as a substrate.

Accepted Answer

A)  acetate 
B)  carbon monoxide 
C)  methane 
D)  methanol 
A)  acetate 
B)  carbon monoxide 
C)  methane 
D)  methanol

Question 2

Describe what occurs when elemental sulfur is provided externally as an electron donor and how energy is obtained.

Accepted Answer

Elemental sulfur (S⁰) can serve as an el

Question 3

Bacteriochlorophyll and chlorophyll contain ________ as a cofactor.

Accepted Answer

A)  iron (II) 
B)  iron (III) 
C)  magnesium 
D)  manganese 
A)  iron (II) 
B)  iron (III) 
C)  magnesium 
D)  manganese

Question 4

Organisms that aerobically catabolize methane use the intermediate ________ for biosynthesis and produce ________ when oxidizing the substrate for energy.

Accepted Answer

A)  CH₂O (formaldehyde) / CO 
B)  CH₂O (formaldehyde) / CO₂ 
C)  HCOO−(formate) / CO 
D)  HCOO−(formate) / CO₂ 
A)  CH₂O (formaldehyde) / CO 
B)  CH₂O (formaldehyde) / CO₂ 
C)  HCOO−(formate) / CO 
D)  HCOO−(formate) / CO₂

Question 5

The Calvin cycle

Accepted Answer

A)  is responsible for the fixation of CO₂ into cell material. 
B)  utilizes both NAD(P)H and ATP. 
C)  requires both ribulose bisphosphate carboxylase and phosphoribulokinase. 
D)  uses CO₂, NAD(P)H, and ATP to make biomass with ribulose bisphosphate carboxylase and phosphoribulokinase. 
A)  is responsible for the fixation of CO₂ into cell material. 
B)  utilizes both NAD(P)H and ATP. 
C)  requires both ribulose bisphosphate carboxylase and phosphoribulokinase. 
D)  uses CO₂, NAD(P)H, and ATP to make biomass with ribulose bisphosphate carboxylase and phosphoribulokinase.

Question 6

Some anaerobic bacteria not only use organic compounds as a carbon source but can also use them for energy as well.

Accepted Answer

A) True 
 B)False

Question 7

The only organisms that perform photosynthesis are ones that produce some form of

Accepted Answer

A)  chlorophyll or bacteriochlorophyll. 
B)  carotenoids. 
C)  phycoerythrin. 
D)  phycocyanin. 
A)  chlorophyll or bacteriochlorophyll. 
B)  carotenoids. 
C)  phycoerythrin. 
D)  phycocyanin.

Question 8

Explain the Calvin cycle process that produces a full molecule of glucose and regenerates the ribulose bisphosphate molecule.

Accepted Answer

It takes 6 CO₂ and 6 ribulose bisphospha

Question 9

Glucose fermentation by Clostridium spp. produces ATP only when acetate and butyrate are produced. Why do these organisms produce acetone and butanol after strong initial activity of generating ATP with acetate and butyrate byproducts?

Accepted Answer

A)  Acetate and butyrate accumulation creates a deadly acidic environment, which acetone and butanol do not. 
B)  Acetate and butyrate are no longer needed for biosynthetic pathways. 
C)  Acetone and butanol serve as better sources for NAD(P)⁺ reduction. 
D)  Acetone and butanol production is favored for stability to store intracellular carbon sources for potential nutrient poor conditions. 
A)  Acetate and butyrate accumulation creates a deadly acidic environment, which acetone and butanol do not. 
B)  Acetate and butyrate are no longer needed for biosynthetic pathways. 
C)  Acetone and butanol serve as better sources for NAD(P)⁺ reduction. 
D)  Acetone and butanol production is favored for stability to store intracellular carbon sources for potential nutrient poor conditions.

Question 10

What is the difference between chlorophyll and bacteriochlorophyll, and which organisms contain each?

Accepted Answer

Chlorophylls are used in phototrophs whe

Question 11

Photosystem I is responsible for splitting a water molecule in the first step of oxygenic electron flow.

Accepted Answer

A) True 
 B)False

Question 12

ʺSpecial pairʺ is the name given to the ________ in the photochemical complex of the purple bacteria.

Accepted Answer

A)  two bacteriochlorophyll a molecules 
B)  two bacteriochlorophyll b molecules 
C)  two quinones 
D)  two reaction centers 
A)  two bacteriochlorophyll a molecules 
B)  two bacteriochlorophyll b molecules 
C)  two quinones 
D)  two reaction centers

Question 13

Which of the following reactions is classified as a heterofermentation?

Accepted Answer

A)  hexose 2 lactate + 2 H⁺ 
B)  HCOOH H₂ + CO₂ 
C)  glucose lactate + ethanol + CO₂ + H⁺ 
D)  fructose 3 acetate + 3 H⁺ 
A)  hexose 2 lactate + 2 H⁺ 
B)  HCOOH H₂ + CO₂ 
C)  glucose lactate + ethanol + CO₂ + H⁺ 
D)  fructose 3 acetate + 3 H⁺

Question 14

Which of the following is NOT a role of carotenoids?

Accepted Answer

A)  as accessory pigments 
B)  photoprotection 
C)  to produce singlet oxygen 
D)  to quench toxic oxygen species 
A)  as accessory pigments 
B)  photoprotection 
C)  to produce singlet oxygen 
D)  to quench toxic oxygen species

Question 15

Membrane vesicles known as chromatophores, which function in photosynthesis, are commonly found in

Accepted Answer

A)  algae. 
B)  green sulfur bacteria. 
C)  most autotrophic organisms. 
D)  purple phototrophic bacteria. 
A)  algae. 
B)  green sulfur bacteria. 
C)  most autotrophic organisms. 
D)  purple phototrophic bacteria.

Question 16

RubisCO converts ribulose bisphosphate and CO₂ into two molecules of 3-phosphoglyceric acid (PGA).

Accepted Answer

A) True 
 B)False

Question 17

How is ATP made by an acetogen during CO₂ fixation?

Accepted Answer

A)  Electrons from metal cofactors energize the electron transport chain and drive the proton motive force to activate ATP synthase. 
B)  Substrate-level phosphorylation of ADP occurs when coenzyme A is removed from acetyl-CoA. 
C)  It is made using substrate level phosphorylation and an ion motive force. 
D)  Acetyl CoA is produced from acetate and ATP is produced through substrate level phosphorylation. 
A)  Electrons from metal cofactors energize the electron transport chain and drive the proton motive force to activate ATP synthase. 
B)  Substrate-level phosphorylation of ADP occurs when coenzyme A is removed from acetyl-CoA. 
C)  It is made using substrate level phosphorylation and an ion motive force. 
D)  Acetyl CoA is produced from acetate and ATP is produced through substrate level phosphorylation.

Question 18

Ferrous iron (Fe²⁺) oxidation generally occurs in environments with

Accepted Answer

A)  alkaline conditions. 
B)  high H⁺ concentrations. 
C)  high oxygen content. 
D)  little or no light present. 
A)  alkaline conditions. 
B)  high H⁺ concentrations. 
C)  high oxygen content. 
D)  little or no light present.

Question 19

Bacteria that are capable of oxidizing both iron and sulfur usually have a strong preference for sulfur oxidation because it yields more energy.

Accepted Answer

A) True 
 B)False

Question 20

Photooxidation reactions can lead to the production of toxic forms of oxygen and the destruction of the photosynthetic apparatus.

Accepted Answer

A) True 
 B)False

Exam 14: Metabolic Diversity of Microorganisms

Methanogens that use methyl-CoM for biosynthesis use ________ as a substrate.

Describe what occurs when elemental sulfur is provided externally as an electron donor and how energy is obtained.

Bacteriochlorophyll and chlorophyll contain ________ as a cofactor.

Organisms that aerobically catabolize methane use the intermediate ________ for biosynthesis and produce ________ when oxidizing the substrate for energy.

The Calvin cycle

Some anaerobic bacteria not only use organic compounds as a carbon source but can also use them for energy as well.

The only organisms that perform photosynthesis are ones that produce some form of

Explain the Calvin cycle process that produces a full molecule of glucose and regenerates the ribulose bisphosphate molecule.

Glucose fermentation by Clostridium spp. produces ATP only when acetate and butyrate are produced. Why do these organisms produce acetone and butanol after strong initial activity of generating ATP with acetate and butyrate byproducts?

What is the difference between chlorophyll and bacteriochlorophyll, and which organisms contain each?

Photosystem I is responsible for splitting a water molecule in the first step of oxygenic electron flow.

ʺSpecial pairʺ is the name given to the ________ in the photochemical complex of the purple bacteria.

Which of the following reactions is classified as a heterofermentation?

Which of the following is NOT a role of carotenoids?

Membrane vesicles known as chromatophores, which function in photosynthesis, are commonly found in

RubisCO converts ribulose bisphosphate and CO₂ into two molecules of 3-phosphoglyceric acid (PGA).

How is ATP made by an acetogen during CO₂ fixation?

Ferrous iron (Fe²⁺) oxidation generally occurs in environments with

Bacteria that are capable of oxidizing both iron and sulfur usually have a strong preference for sulfur oxidation because it yields more energy.

Photooxidation reactions can lead to the production of toxic forms of oxygen and the destruction of the photosynthetic apparatus.

The Microbial World

Microbial Cell Structure and Function

Microbial Metabolism

Molecular Information Flow and Protein Processing

Microbial Growth and Its Control

Microbial Regulatory Systems

Molecular Biology of Microbial Growth

Viruses and Their Replication

Microbial Systems Biology

Viral Genomics, Diversity, and Ecology

Genetics of Bacteria and Archaea

Biotechnology and Synthetic Biology

Microbial Evolution and Systematics

Functional Diversity of Microorganisms

Diversity of Bacteria

Diversity of Archaea

Diversity of Microbial Eukarya

Taking the Measure of Microbial Systems

Microbial Ecosystems

Nutrient Cycles

Microbiology of the Built Environment

Microbial Symbioses

Microbial Symbioses with Humans

Microbial Infection and Pathogenesis

Innate Immunity: Broadly Specific Host Defenses

Adaptive Immunity: Highly Specific Host Defenses

Clinical Microbiology and Immunology

Epidemiology

Person-to-Person Bacterial and Viral Diseases

Vectorborne and Soilborne Bacterial and Viral Diseases

Waterborne and Foodborne Bacterial and Viral Diseases

Eukaryotic Pathogens: Fungi, Protozoans, and Helminths

Filters

Organisms that aerobically catabolize methane use the intermediate for biosynthesis and produce when oxidizing the substrate for energy.