Question 1

The genus of bacteria that is able to fix nitrogen and form heterocysts is

Accepted Answer

A)  Pseudomonas. 
B)  Anabaena. 
C)  Escherichia. 
D)  Vibrio. 
E)  Streptococcus. 
A)  Pseudomonas. 
B)  Anabaena. 
C)  Escherichia. 
D)  Vibrio. 
E)  Streptococcus. B

Question 2

What distinguishes Staphylococcus, species from Streptococcus, Enterococcus and Lactococcus species?

Accepted Answer

A)  Their morphology. 
B)  The nature of their cell walls. 
C)  The production of catalase. 
D)  Their ability to cause disease. 
E)  All of these. 
A)  Their morphology. 
B)  The nature of their cell walls. 
C)  The production of catalase. 
D)  Their ability to cause disease. 
E)  All of these. C

Question 3

Many spirochetes are difficult to cultivate, so their classification is based on their

Accepted Answer

A)  morphology AND ability to cause disease. 
B)  number of flagella AND morphology. 
C)  pattern of pili AND flexible cell wall. 
D)  number of chromosomes AND pattern of flagella. 
E)  ability to cause disease AND pattern of flagella. 
A)  morphology AND ability to cause disease. 
B)  number of flagella AND morphology. 
C)  pattern of pili AND flexible cell wall. 
D)  number of chromosomes AND pattern of flagella. 
E)  ability to cause disease AND pattern of flagella. A

Question 4

Bacteria and Archaea both have members that use sulfur compounds as a terminal electron acceptor.

Accepted Answer

A) True 
 B)False

Question 5

Pseudomonas species

Accepted Answer

A)  are resistant to many disinfectants and antimicrobials AND do not contain plasmids. 
B)  are mostly harmless except for the opportunistic P. aeruginosa AND do not contain plasmids. 
C)  require nutrient-rich environments AND are mostly harmless except for the opportunistic P. aeruginosa. 
D)  require nutrient-rich environments AND do not contain plasmids. 
E)  are resistant to many disinfectants and antimicrobials AND are mostly harmless except for the opportunistic P. aeruginosa. 
A)  are resistant to many disinfectants and antimicrobials AND do not contain plasmids. 
B)  are mostly harmless except for the opportunistic P. aeruginosa AND do not contain plasmids. 
C)  require nutrient-rich environments AND are mostly harmless except for the opportunistic P. aeruginosa. 
D)  require nutrient-rich environments AND do not contain plasmids. 
E)  are resistant to many disinfectants and antimicrobials AND are mostly harmless except for the opportunistic P. aeruginosa.

Question 6

A particular characteristic of disease-causing Streptococcus is

Accepted Answer

A)  catalase production. 
B)  beta-hemolysis. 
C)  lactic acid production. 
D)  growth at refrigerator temperatures. 
E)  endospore formation. 
A)  catalase production. 
B)  beta-hemolysis. 
C)  lactic acid production. 
D)  growth at refrigerator temperatures. 
E)  endospore formation.

Question 7

Anoxygenic phototrophs

Accepted Answer

A)  produce oxygen. 
B)  use water as a source of electrons. 
C)  use hydrogen sulfide or organic compounds as a source of electrons. 
D)  use the same form of chlorophyll found in terrestrial plants. 
E)  produce oxygen AND use the same form of chlorophyll found in terrestrial plants. 
A)  produce oxygen. 
B)  use water as a source of electrons. 
C)  use hydrogen sulfide or organic compounds as a source of electrons. 
D)  use the same form of chlorophyll found in terrestrial plants. 
E)  produce oxygen AND use the same form of chlorophyll found in terrestrial plants.

Question 8

Which of the following structures would be the best choice as a biological indicator to test autoclave operations?

Accepted Answer

A)  Cysts formed by Azotobacter species. 
B)  Microcysts within the fruiting bodies of myxobacteria. 
C)  Dormant spores in the conidia of Streptomyces species. 
D)  Endospores formed by Geobacillus stearothermophilus. 
E)  Sulfur granules produced by Thiothrix species. 
A)  Cysts formed by Azotobacter species. 
B)  Microcysts within the fruiting bodies of myxobacteria. 
C)  Dormant spores in the conidia of Streptomyces species. 
D)  Endospores formed by Geobacillus stearothermophilus. 
E)  Sulfur granules produced by Thiothrix species.

Question 9

Heterocysts

Accepted Answer

A)  are found in nitrogen-fixing cyanobacteria AND produce catalase. 
B)  are found in nitrogen-fixing cyanobacteria AND are used to protect nitrogenase. 
C)  are used to protect nitrogenase AND generate oxygen. 
D)  produce catalase AND are found in nitrogen-fixing cyanobacteria. 
E)  are found in nitrogen-fixing cyanobacteria AND generate oxygen. 
A)  are found in nitrogen-fixing cyanobacteria AND produce catalase. 
B)  are found in nitrogen-fixing cyanobacteria AND are used to protect nitrogenase. 
C)  are used to protect nitrogenase AND generate oxygen. 
D)  produce catalase AND are found in nitrogen-fixing cyanobacteria. 
E)  are found in nitrogen-fixing cyanobacteria AND generate oxygen.

Question 10

Azotobacter

Accepted Answer

A)  forms endospores. 
B)  fixes nitrogen. 
C)  fixes carbon dioxide. 
D)  is used as an indicator of fecal pollution. 
E)  is a hyperthermophile. 
A)  forms endospores. 
B)  fixes nitrogen. 
C)  fixes carbon dioxide. 
D)  is used as an indicator of fecal pollution. 
E)  is a hyperthermophile.

Question 11

Approximately 99% of the microbes in the intestines are obligate anaerobes. We have plenty of blood vessels that can bring oxygen to the tissues of the intestines. Why would there be obligate anaerobes within these areas?

Accepted Answer

A)  The bacteria in the intestines are protected from exposure to the oxygen in the tissues by the lining of the intestines. 
B)  The bacteria consume all the oxygen in the tissue areas brought by the blood vessels, creating an anaerobic environment. 
C)  The inside space of the intestines is highly anaerobic. It is deep inside the body where oxygen cannot reach and it is not supplied with blood. 
D)  The aerobic microbes are outcompeted for nutrients in these areas by the anaerobic microbes. 
E)  The inside space of the intestines is highly anaerobic. It is deep inside the body where carbon dioxide accumulates. 
A)  The bacteria in the intestines are protected from exposure to the oxygen in the tissues by the lining of the intestines. 
B)  The bacteria consume all the oxygen in the tissue areas brought by the blood vessels, creating an anaerobic environment. 
C)  The inside space of the intestines is highly anaerobic. It is deep inside the body where oxygen cannot reach and it is not supplied with blood. 
D)  The aerobic microbes are outcompeted for nutrients in these areas by the anaerobic microbes. 
E)  The inside space of the intestines is highly anaerobic. It is deep inside the body where carbon dioxide accumulates.

Question 12

Which of the following about Mycoplasma is False?

Accepted Answer

A)  They lack peptidoglycan. 
B)  They are the smallest free-living organisms. 
C)  They have sterols in their membranes. 
D)  They are killed by penicillin. 
E)  They are pleomorphic. 
A)  They lack peptidoglycan. 
B)  They are the smallest free-living organisms. 
C)  They have sterols in their membranes. 
D)  They are killed by penicillin. 
E)  They are pleomorphic.

Question 13

Hydrogen sulfide

Accepted Answer

A)  is produced when nitrate is used as terminal electron acceptor. 
B)  is produced by Desulfovibrio. 
C)  may react with iron to produce a deep red precipitate. 
D)  has a strong citrus smell. 
E)  All of the answer choices are correct. 
A)  is produced when nitrate is used as terminal electron acceptor. 
B)  is produced by Desulfovibrio. 
C)  may react with iron to produce a deep red precipitate. 
D)  has a strong citrus smell. 
E)  All of the answer choices are correct.

Question 14

Movement of spirochetes occurs by means of structures called

Accepted Answer

A)  cilia. 
B)  flagella. 
C)  endoflagella. 
D)  pili. 
E)  microvilli. 
A)  cilia. 
B)  flagella. 
C)  endoflagella. 
D)  pili. 
E)  microvilli.

Question 15

Chlamydia occurs in two forms, a reticulate body and an elementary body.

Accepted Answer

A) True 
 B)False

Question 16

How do anoxygenic phototrophs benefit from having accessory pigments that allow light to be harvested at deeper areas of a moist or aquatic environment?

Accepted Answer

A)  Accessory pigments allows even anaerobic microbes to carry out photosynthesis, as they can harvest light energy in the deeper areas where oxygen won't be present. 
B)  The cells can use wavelengths of light that have not been absorbed by the photosynthetic organisms closer to the surface of the water. 
C)  These organisms don't have to compete with other cells that use oxygen in the upper levels for the scarce nutrients in the aquatic environment. 
D)  This allows even anaerobic microbes to conduct photosynthesis, as they can harvest light energy in the deeper areas where oxygen won't be present AND can use wavelengths of light not absorbed by the photosynthetic organisms closer to the surface of the fluid. 
E)  This allows even anaerobic microbes to conduct photosynthesis, as they can harvest light energy in the deeper areas where oxygen won't be present, use wavelengths of light not absorbed by the photosynthetic organisms closer to the surface of the water; AND don't have to compete with other cells that use oxygen in the upper levels for the scarce nutrients in the fluid environment. 
A)  Accessory pigments allows even anaerobic microbes to carry out photosynthesis, as they can harvest light energy in the deeper areas where oxygen won't be present. 
B)  The cells can use wavelengths of light that have not been absorbed by the photosynthetic organisms closer to the surface of the water. 
C)  These organisms don't have to compete with other cells that use oxygen in the upper levels for the scarce nutrients in the aquatic environment. 
D)  This allows even anaerobic microbes to conduct photosynthesis, as they can harvest light energy in the deeper areas where oxygen won't be present AND can use wavelengths of light not absorbed by the photosynthetic organisms closer to the surface of the fluid. 
E)  This allows even anaerobic microbes to conduct photosynthesis, as they can harvest light energy in the deeper areas where oxygen won't be present, use wavelengths of light not absorbed by the photosynthetic organisms closer to the surface of the water; AND don't have to compete with other cells that use oxygen in the upper levels for the scarce nutrients in the fluid environment.

Question 17

It has been estimated that 99% of intestinal bacteria are

Accepted Answer

A)  obligate aerobes. 
B)  facultative anaerobes. 
C)  obligate anaerobes. 
D)  facultative aerobes. 
E)  thermophiles. 
A)  obligate aerobes. 
B)  facultative anaerobes. 
C)  obligate anaerobes. 
D)  facultative aerobes. 
E)  thermophiles.

Question 18

Thermus and Deinococcus

Accepted Answer

A)  are both thermophilic. 
B)  are both radiation resistant. 
C)  both serve as the source of Taq polymerase. 
D)  are both Gram-positive. 
E)  survive in extreme environments. 
A)  are both thermophilic. 
B)  are both radiation resistant. 
C)  both serve as the source of Taq polymerase. 
D)  are both Gram-positive. 
E)  survive in extreme environments.

Question 19

Rhizobium is considered an endosymbiont with plants.

Accepted Answer

A) True 
 B)False

Question 20

The methanogens

Accepted Answer

A)  are part of the domain Archaea AND appear only in aerobic environments. 
B)  oxidize hydrogen gas to produce methane AND appear only in aerobic environments. 
C)  use oxygen as a terminal electron acceptor AND appear only in aerobic environments. 
D)  use oxygen as a terminal electron acceptor AND oxidize hydrogen gas to produce methane. 
E)  are part of the domain Archaea AND oxidize hydrogen gas to produce methane. 
A)  are part of the domain Archaea AND appear only in aerobic environments. 
B)  oxidize hydrogen gas to produce methane AND appear only in aerobic environments. 
C)  use oxygen as a terminal electron acceptor AND appear only in aerobic environments. 
D)  use oxygen as a terminal electron acceptor AND oxidize hydrogen gas to produce methane. 
E)  are part of the domain Archaea AND oxidize hydrogen gas to produce methane.

Exam 11: The Diversity of Bacteria and Archaea

The genus of bacteria that is able to fix nitrogen and form heterocysts is

What distinguishes Staphylococcus, species from Streptococcus, Enterococcus and Lactococcus species?

Many spirochetes are difficult to cultivate, so their classification is based on their

Bacteria and Archaea both have members that use sulfur compounds as a terminal electron acceptor.

Pseudomonas species

A particular characteristic of disease-causing Streptococcus is

Anoxygenic phototrophs

Which of the following structures would be the best choice as a biological indicator to test autoclave operations?

Heterocysts

Azotobacter

Approximately 99% of the microbes in the intestines are obligate anaerobes. We have plenty of blood vessels that can bring oxygen to the tissues of the intestines. Why would there be obligate anaerobes within these areas?

Which of the following about Mycoplasma is False?

Hydrogen sulfide

Movement of spirochetes occurs by means of structures called

Chlamydia occurs in two forms, a reticulate body and an elementary body.

How do anoxygenic phototrophs benefit from having accessory pigments that allow light to be harvested at deeper areas of a moist or aquatic environment?

It has been estimated that 99% of intestinal bacteria are

Thermus and Deinococcus

Rhizobium is considered an endosymbiont with plants.

The methanogens

Humans and the Microbial World

The Molecules of Life

Microscopy and Cell Structure

Dynamics of Microbial Growth

Control of Microbial Growth

Microbial Metabolism: Fueling Cell Growth

The Blueprint of Life, from DNA to Protein

Bacterial Genetics

Biotechnology

Identifying and Classifying Microorganisms

The Eukaryotic Members of the Microbial World

Viruses, Viroids, and Prions

The Innate Immune Response

The Adaptive Immune Response

Host-Microbe Interactions

Immunological Disorders

Applications of Immune Responses

Epidemiology

Antimicrobial Medications

Respiratory System Infections

Skin Infections

Wound Infections

Digestive System Infections

Blood and Lymphatic Infections

Nervous System Infections

Genitourinary Tract Infections

Microbial Ecology

Environmental Microbiology: Treatment of Water, Wastes, and Polluted Habitats

Food Microbiology

Filters