Question 1

The hadobacteria are thermophilic extremophiles.They include the genus Deinococcus, which

Accepted Answer

A)  can consume nuclear waste and other toxic materials. 
B)  cannot tolerate extreme cold. 
C)  causes tuberculosis. 
D)  is an important source of antibiotics. 
E)  causes sexually transmitted diseases in humans. 
A)  can consume nuclear waste and other toxic materials. 
B)  cannot tolerate extreme cold. 
C)  causes tuberculosis. 
D)  is an important source of antibiotics. 
E)  causes sexually transmitted diseases in humans.

Question 2

Match the name of the bacteria from the list below with the description that follows.

Accepted Answer

A)  Cyanobacteria 
B)  Spirochetes 
C)  Chlamydias 
D)  Gram-negative, rod-shaped bacteria 
E)  Actinobacteria These bacteria are small intracellular parasites that have a unique, complex reproductive cycle and include strains that cause eye infections and venereal disease. 
A)  Cyanobacteria 
B)  Spirochetes 
C)  Chlamydias 
D)  Gram-negative, rod-shaped bacteria 
E)  Actinobacteria These bacteria are small intracellular parasites that have a unique, complex reproductive cycle and include strains that cause eye infections and venereal disease.

Question 3

Unknown bacteria are cultured from a scaly patch on the skin's surface.Upon further characterization, they are found to contain half the DNA of most bacteria and are not affected by the application of penicillin.Based on these two criteria, you conclude these bacteria are

Accepted Answer

A)  mycoplasmas. 
B)  actinobacteria. 
C)  prokaryotic archaea. 
D)  cyanobacteria. 
E)  spirochetes. 
A)  mycoplasmas. 
B)  actinobacteria. 
C)  prokaryotic archaea. 
D)  cyanobacteria. 
E)  spirochetes.

Question 4

Gram-negative bacteria usually have a thin peptidoglycan layer and an outer _______.

Accepted Answer

The answer of Gram-negative bacteria usually have a thin peptidoglycan...

Question 5

Which statement concerning endospores is false?

Accepted Answer

A)  They can survive harsh environmental conditions that would kill the parent cell. 
B)  They undergo meiosis and produce haploid gametes. 
C)  They can survive high or low temperatures. 
D)  In favorable conditions, they become metabolically active and divide, forming new cells. 
E)  Some have been reactivated after more than 1,000 years of dormancy. 
A)  They can survive harsh environmental conditions that would kill the parent cell. 
B)  They undergo meiosis and produce haploid gametes. 
C)  They can survive high or low temperatures. 
D)  In favorable conditions, they become metabolically active and divide, forming new cells. 
E)  Some have been reactivated after more than 1,000 years of dormancy.

Question 6

Prokaryotic archaea are characterized by

Accepted Answer

A)  their unique cell shape. 
B)  lipids containing unbranched, long-chain hydrocarbons. 
C)  the presence of peptidoglycan. 
D)  lipids containing hydrocarbons connected to glycerol by ether linkages. 
E)  the presence of membrane-bound organelles. 
A)  their unique cell shape. 
B)  lipids containing unbranched, long-chain hydrocarbons. 
C)  the presence of peptidoglycan. 
D)  lipids containing hydrocarbons connected to glycerol by ether linkages. 
E)  the presence of membrane-bound organelles.

Question 7

Bacteria that are unable to survive for extended periods in the absence of oxygen are called _______.

Accepted Answer

The answer of Bacteria that are unable to survive for...

Question 8

When stained with Gram stain, Gram-positive bacteria stain blue to purple (or violet), whereas Gram-negative bacteria stain _______.

Accepted Answer

The answer of When stained with Gram stain, Gram-positive bacteria...

Question 9

The bacterium Escherichia coli is rod-shaped and is Gram-_______.

Accepted Answer

The answer of The bacterium Escherichia coli is rod-shaped and...

Question 10

Some prokaryotes are photoheterotrophs, which obtain energy from _______ and obtain carbon from _______.

Accepted Answer

A)  light; CO2, such as atmospheric CO2 
B)  light; organic compounds made by other organisms 
C)  CO2; oxidizing inorganic substances 
D)  organic compounds made by other organisms; organic compounds made by other organisms 
E)  organic compounds made by other organisms; light 
A)  light; CO2, such as atmospheric CO2 
B)  light; organic compounds made by other organisms 
C)  CO2; oxidizing inorganic substances 
D)  organic compounds made by other organisms; organic compounds made by other organisms 
E)  organic compounds made by other organisms; light

Question 11

Your research group is interested in studying a bacterium known to associate with the roots of soybean plants.When the bacterium is present, the plants grow taller and produce higher yields.Choose the experimental setup that would provide an explanation for this observed phenomenon.

Accepted Answer

A)  Incubate the bacterium with nitrate, and observe whether atmospheric N2 is released. 
B)  Incubate the bacterium in a solution bubbled with N2 gas, and observe whether NH4+ accumulates in solution. 
C)  Incubate the bacterium with ammonia, and observe whether nitrate forms. 
D)  Incubate the bacterium with nitrite ions, and observe whether nitrate forms. 
E)  Incubate the bacterium with ammonia, and observe whether atmospheric N2 is released. 
A)  Incubate the bacterium with nitrate, and observe whether atmospheric N2 is released. 
B)  Incubate the bacterium in a solution bubbled with N2 gas, and observe whether NH4+ accumulates in solution. 
C)  Incubate the bacterium with ammonia, and observe whether nitrate forms. 
D)  Incubate the bacterium with nitrite ions, and observe whether nitrate forms. 
E)  Incubate the bacterium with ammonia, and observe whether atmospheric N2 is released.

Question 12

Organisms require energy to carry out metabolic activities, and prokaryote species occur in all nutrition-obtaining categories.Organisms classified as _______ obtain their energy by oxidizing inorganic substances such as ammonia, nitrate, hydrogen sulfide, and sulfur.

Accepted Answer

A)  photoautotrophs 
B)  chemoheterotrophs 
C)  photoheterotrophs 
D)  chemoautotrophs 
E)  photochemotrophs 
A)  photoautotrophs 
B)  chemoheterotrophs 
C)  photoheterotrophs 
D)  chemoautotrophs 
E)  photochemotrophs

Question 13

In an effort to lead a healthier lifestyle, you reduce the amount of sugar in your diet and start using a sugar substitute that tastes sweet but is not taken up by mammalian cells.After a few weeks you experience stomach cramps and lethargy.Based on what you know about microbiomes, what would be a reasonable hypothesis to explain your discomfort?

Accepted Answer

A)  The bacteria living in your gut have become aerobic and can no longer survive in your intestines. 
B)  The bacteria living in your gut have become pathogenic and are funneling nutrients from your cells. 
C)  The composition of bacterial species normally present in your intestines has changed, and thus compromised your body's ability to function normally. 
D)  The bacterial species in your gut have formed a biofilm. 
E)  You are allergic to the sugar substitute. 
A)  The bacteria living in your gut have become aerobic and can no longer survive in your intestines. 
B)  The bacteria living in your gut have become pathogenic and are funneling nutrients from your cells. 
C)  The composition of bacterial species normally present in your intestines has changed, and thus compromised your body's ability to function normally. 
D)  The bacterial species in your gut have formed a biofilm. 
E)  You are allergic to the sugar substitute.

Question 14

Refer to the figure, which shows the formation of a biofilm.   According to the figure, which statement about biofilms is false?

Accepted Answer

A)  Once in a biofilm, bacteria cannot escape from it. 
B)  A biofilm forms on surfaces. 
C)  Bacteria within biofilms divide. 
D)  Biofilms attract other organisms. 
E)  A biofilm is not considered mature until there are multiple species present. 
A)  Once in a biofilm, bacteria cannot escape from it. 
B)  A biofilm forms on surfaces. 
C)  Bacteria within biofilms divide. 
D)  Biofilms attract other organisms. 
E)  A biofilm is not considered mature until there are multiple species present.

Question 15

A drug that blocks formation of axial filaments would

Accepted Answer

A)  prevent cell formation. 
B)  prevent locomotion in spirochetes. 
C)  block signaling of biofilms. 
D)  prevent photosynthesis in archaea. 
E)  prevent cell wall formation in spirochetes. 
A)  prevent cell formation. 
B)  prevent locomotion in spirochetes. 
C)  block signaling of biofilms. 
D)  prevent photosynthesis in archaea. 
E)  prevent cell wall formation in spirochetes.

Question 16

Match the name of the bacteria from the list below with the description that follows.

Accepted Answer

A)  Cyanobacteria 
B)  Spirochetes 
C)  Chlamydias 
D)  Gram-negative, rod-shaped bacteria 
E)  Actinobacteria These bacteria are not a monophyletic group. 
A)  Cyanobacteria 
B)  Spirochetes 
C)  Chlamydias 
D)  Gram-negative, rod-shaped bacteria 
E)  Actinobacteria These bacteria are not a monophyletic group.

Question 17

Bacteria are known for the many roles they play in biological communities.Which of the following is the most rare role for this group of organisms?

Accepted Answer

A)  Pathogen 
B)  Digestive aid 
C)  Nitrogen and sulfur processor in soils 
D)  Decomposer 
E)  Industrial and agricultural use 
A)  Pathogen 
B)  Digestive aid 
C)  Nitrogen and sulfur processor in soils 
D)  Decomposer 
E)  Industrial and agricultural use

Question 18

Clostridium and Escherichia coli are both well-known genera of rod-shaped bacteria, but they are classified into different groups based on their peptidoglycan content.If Clostridium stains purple during a Gram stain test, then we know that E.coli is

Accepted Answer

A)  an archaeon. 
B)  Gram-positive. 
C)  a eukaryote. 
D)  Gram-negative. 
E)  a spirochete. 
A)  an archaeon. 
B)  Gram-positive. 
C)  a eukaryote. 
D)  Gram-negative. 
E)  a spirochete.

Question 19

Lateral gene transfer most likely accounts for

Accepted Answer

A)  the acquisition of antibiotic resistance in many strains of unrelated bacteria. 
B)  the presence of rRNA in all free-living organisms. 
C)  the maintenance of core genes essential for fundamental cellular processes. 
D)  discrepancies in assigning organisms at higher taxonomic levels. 
E)  the development of chloroplasts and mitochondria in eukaryotes. 
A)  the acquisition of antibiotic resistance in many strains of unrelated bacteria. 
B)  the presence of rRNA in all free-living organisms. 
C)  the maintenance of core genes essential for fundamental cellular processes. 
D)  discrepancies in assigning organisms at higher taxonomic levels. 
E)  the development of chloroplasts and mitochondria in eukaryotes.

Question 20

Which of the following is not a potential application of biofilms?

Accepted Answer

A)  The creation of an impermeable film to protect teeth from decay. 
B)  A biofilm "transplant," composed of beneficial gut microbes to replace microbes known to cause obesity. 
C)  The use of biofilm formation as a qualitative indicator of cell density. 
D)  The introduction of biofilms to break down metal waste. 
E)  The study of fossilized biofilms to evaluate and learn about the history of life on Earth. 
A)  The creation of an impermeable film to protect teeth from decay. 
B)  A biofilm "transplant," composed of beneficial gut microbes to replace microbes known to cause obesity. 
C)  The use of biofilm formation as a qualitative indicator of cell density. 
D)  The introduction of biofilms to break down metal waste. 
E)  The study of fossilized biofilms to evaluate and learn about the history of life on Earth.

Exam 25: Bacteria, Archaea, and Viruses

The hadobacteria are thermophilic extremophiles.They include the genus Deinococcus, which

Match the name of the bacteria from the list below with the description that follows.

Unknown bacteria are cultured from a scaly patch on the skin's surface.Upon further characterization, they are found to contain half the DNA of most bacteria and are not affected by the application of penicillin.Based on these two criteria, you conclude these bacteria are

Gram-negative bacteria usually have a thin peptidoglycan layer and an outer _______.

Which statement concerning endospores is false?

Prokaryotic archaea are characterized by

Bacteria that are unable to survive for extended periods in the absence of oxygen are called _______.

When stained with Gram stain, Gram-positive bacteria stain blue to purple (or violet), whereas Gram-negative bacteria stain _______.

The bacterium Escherichia coli is rod-shaped and is Gram-_______.

Some prokaryotes are photoheterotrophs, which obtain energy from _______ and obtain carbon from _______.

Your research group is interested in studying a bacterium known to associate with the roots of soybean plants.When the bacterium is present, the plants grow taller and produce higher yields.Choose the experimental setup that would provide an explanation for this observed phenomenon.

Organisms require energy to carry out metabolic activities, and prokaryote species occur in all nutrition-obtaining categories.Organisms classified as _______ obtain their energy by oxidizing inorganic substances such as ammonia, nitrate, hydrogen sulfide, and sulfur.

Refer to the figure, which shows the formation of a biofilm. According to the figure, which statement about biofilms is false?

A drug that blocks formation of axial filaments would

Match the name of the bacteria from the list below with the description that follows.

Bacteria are known for the many roles they play in biological communities.Which of the following is the most rare role for this group of organisms?

Clostridium and Escherichia coli are both well-known genera of rod-shaped bacteria, but they are classified into different groups based on their peptidoglycan content.If Clostridium stains purple during a Gram stain test, then we know that E.coli is

Lateral gene transfer most likely accounts for

Which of the following is not a potential application of biofilms?

Studying Life

Small Molecules and the Chemistry of Life

Proteins, Carbohydrates, and Lipids

Nucleic Acids and the Origin of Life

Cells: the Working Units of Life

Cell Membranes

Cell Communication and Multicellularity

Energy, Enzymes, and Metabolism

Pathways That Harvest Chemical Energy

Photosynthesis: Energy From Sunlight

The Cell Cycle and Cell Division

Inheritance, Genes, and Chromosomes

Dna and Its Role in Heredity

From Dna to Protein: Gene Expression

Gene Mutation and Molecular Medicine

Regulation of Gene Expression

Genomes

Recombinant Dna and Biotechnology

Mechanisms of Evolution

Reconstructing and Using Phylogenies

Speciation

Evolution of Genes and Genomes

The History of Life on Earth

The Origin and Diversification of Eukaryotes

Plants Without Seeds: From Water to Land

The Evolution of Seed Plants

The Evolution and Diversity of Fungi

Animal Origins and the Evolution of Body Plans

Protostome Animals

Deuterostome Animals

The Plant Body

Transport in Plants

Plant Nutrition

Regulation of Plant Growth

Reproduction in Flowering Plants

Plant Responses to Environmental Challenges

Physiology, Homeostasis, and Temperature Regulation

Animal Hormones

Immunology: Animal Defense Systems

Animal Reproduction

Animal Development

Neurons, Glia, and Nervous Systems

Sensory Systems

The Mammalian Nervous System: Structure and Higher Functions

Musculoskeletal Systems

Gas Exchange

Circulatory Systems

Nutrition, Digestion, and Absorption

Salt and Water Balance and Nitrogen Excretion

Animal Behavior

The Physical Environment and Biogeography of Life

Populations

Species Interactions

Communities

Ecosystems

A Changing Biosphere

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Some prokaryotes are photoheterotrophs, which obtain energy from _ and obtain carbon from _.