Microbiology 1st Edition By Wessner - Test Bank

Microbiology 1st Edition By Wessner – Test Bank

 

Instant Download – Complete Test Bank With Answers

 

 

Sample Questions Are Posted Below

 

Package Title: Test Bank

Course Title: Wessner1e

Chapter Number: 5

 

 

Question Type: Multiple Choice

 

 

1) Which of these comprises the viral genome?

 

1. a) single-stranded DNA
2. b) single-stranded RNA
3. c) double-stranded DNA
4. d) double-stranded RNA
5. e) All of these choices are seen in viruses.

 

Answer: e

 

Difficulty: Easy

Learning Objective: LO 5.1 Explain the unique properties of viruses and how they are categorized.

Section Reference: Section 5.1 A basic overview of viruses

 

 

2) What is the viral capsid composed of?

 

1. a) protein
2. b) nucleic acid
3. c) lipid
4. d) polysaccharide
5. e) glycogen

 

Answer: a

 

Difficulty: Easy

Learning Objective: LO 5.1 Explain the unique properties of viruses and how they are categorized.

Section Reference: Section 5.1 A basic overview of viruses

 

 

3) What protective structure contains the viral nucleic acid?

 

1. a) envelope
2. b) nucleus
3. c) capsid
4. d) endosome
5. e) vacuole

 

Answer: c

 

Difficulty: Easy

Learning Objective: LO 5.1 Explain the unique properties of viruses and how they are categorized.

Section Reference: Section 5.1 A basic overview of viruses

 

 

4) The field of virology started in the late _______ after Dimitri Ivanovski demonstrated that the infectious agent that caused disease in a tobacco plants could pass through a filter small enough to exclude any known bacterium.

 

1. a) 1500s
2. b) 1600s
3. c) 1700s
4. d) 1800s
5. e) 1900s

 

Answer: d

 

Difficulty: Easy

Learning Objective: LO 5.1 Explain the unique properties of viruses and how they are categorized.

Section Reference: Section 5.1 A basic overview of viruses

 

 

5) What is the average size of a virus?

 

1. a) 10 – 100 nm
2. b) 0.5 – 1 µm
3. c) 5 – 10 µm
4. d) 100 – 500 µm.
5. e) 1 – 10 mm

 

Answer: a

 

Difficulty: Easy

Learning Objective: LO 5.1 Explain the unique properties of viruses and how they are categorized.

Section Reference: Section 5.1 A basic overview of viruses

 

 

6) What general shape is a virus with helical capsid symmetry?

 

1. a) icosahedral
2. b) spherical
3. c) round
4. d) rod shaped
5. e) square

 

Answer: d

 

Difficulty: Easy

Learning Objective: LO 5.1 Explain the unique properties of viruses and how they are categorized.

Section Reference: Section 5.1 A basic overview of viruses

 

 

7) Most viruses with helical capsid symmetry contain _______ as their nucleic acid.

 

1. a) single-stranded DNA
2. b) single-stranded RNA
3. c) double-stranded DNA
4. d) double-stranded RNA
5. e) RNA/DNA dimer

 

Answer: b

 

Difficulty: Medium

Learning Objective: LO 5.1 Explain the unique properties of viruses and how they are categorized.

Section Reference: Section 5.1 A basic overview of viruses

 

 

8) Viruses that have icosahedral symmetry have ________ faces and 12 vertices resulting in a spherical appearance.

 

1. a) 10
2. b) 20
3. c) 30
4. d) 40
5. e) 50

 

Answer: b

 

Difficulty: Easy

Learning Objective: LO 5.1 Explain the unique properties of viruses and how they are categorized.

Section Reference: Section 5.1 A basic overview of viruses

 

 

9) Enveloped viruses are mainly associated with which of the following?

 

1. a) plants and bacteria
2. b) animals
3. c) bacteria
4. d) plant and animals
5. e) plants

 

Answer: b

 

Difficulty: Medium

Learning Objective: LO 5.1 Explain the unique properties of viruses and how they are categorized.

Section Reference: Section 5.1 A basic overview of viruses

 

 

10) What is the first step in the viral replication cycle?

 

1. a) RNA synthesis
2. b) genome synthesis
3. c) entry into the cell
4. d) attachment to the cell
5. e) viral RNA translation

 

Answer: d

 

Difficulty: Easy

Learning Objective: LO 5.1 Explain the unique properties of viruses and how they are categorized.

Section Reference: Section 5.1 A basic overview of viruses

 

 

11) What is the most common way for non-enveloped viruses to enter animal cells?

 

1. a) The virion fuses itself to the cell membrane.
2. b) The virion directly injects its nucleic acid.
3. c) Endocytosis of the virion.
4. d) Through lysis of the cell.
5. e) Via a hole in the cell membrane.

 

Answer: c

 

Difficulty: Easy

Learning Objective: LO 5.1 Explain the unique properties of viruses and how they are categorized.

Section Reference: Section 5.1 A basic overview of viruses

 

 

12) What is the most common way for enveloped viruses to enter animal cells?

 

1. a) The virion fuses itself to the cell membrane.
2. b) The virion directly injects its nucleic acid.
3. c) Endocytosis of the virion.
4. d) Through lysis of the cell.
5. e) Via a hole in the cell membrane.

 

Answer: a

 

Difficulty: Easy

Learning Objective: LO 5.1 Explain the unique properties of viruses and how they are categorized.

Section Reference: Section 5.1 A basic overview of viruses

 

 

13) Plant viruses often enter into a plant cell:

 

1. a) through fusion of the virion to the cell membrane.
2. b) through direct injection of the viral nucleic acid.
3. c) as a result of insects feeding on the plant.
4. d) by endocytosis.
5. e) by phagocytosis.

 

Answer: c

 

Difficulty: Easy

Learning Objective: LO 5.1 Explain the unique properties of viruses and how they are categorized.

Section Reference: Section 5.1 A basic overview of viruses

 

 

14) How do bacteriophages invade the bacteria cell?

 

1. a) The bacteriophage fuses itself to the cell membrane.
2. b) The bacteriophage directly injects its nucleic acid.
3. c) Endocytosis of the bacteriophage.
4. d) Through lysis of the cell.
5. e) Via a hole in the cell membrane.

 

Answer: b

 

Difficulty: Easy

Learning Objective: LO 5.1 Explain the unique properties of viruses and how they are categorized.

Section Reference: Section 5.1 A basic overview of viruses

 

 

15) A single virus-infected cell may produce up to __________ new virions.

 

1. a) 10
2. b) 100
3. c) 1000
4. d) 10,000
5. e) one million

 

Answer: d

 

Difficulty: Medium

Learning Objective: LO 5.1 Explain the unique properties of viruses and how they are categorized.

Section Reference: Section 5.1 A basic overview of viruses

 

 

16) Many enveloped viruses exit their host cell through a process called _________.

 

1. a) exocytosis
2. b) budding
3. c) cell lysis
4. d) receptor-mediated endocytosis
5. e) phagocytosis

 

Answer: b

 

Difficulty: Easy

Learning Objective: LO 5.1 Explain the unique properties of viruses and how they are categorized.

Section Reference: Section 5.1 A basic overview of viruses

 

 

17) What is the premise of the coevolution hypothesis of viral evolution?

 

1. a) Viruses appeared after the first cells were well established.
2. b) Viruses arose from excess DNA of cells.
3. c) Viruses first appeared before or at the same time as the first primordial cells.
4. d) Viruses first appeared about a million years ago and continue to evolve along with their hosts.
5. e) Viruses originated when some cells lost the ability to replicate on their own.

 

Answer: c

 

Difficulty: Medium

Learning Objective: LO 5.2 Explain the various hypotheses regarding the origins of viruses and the evidence for each.

Section Reference: Section 5.2 Origins of viruses

 

 

18) What is the premise of the progressive hypothesis of viral origin?

 

1. a) Viruses evolved from symbionts of cells.
2. b) Viruses evolved from self-replicating nucleic acid segments.
3. c) Viruses originated from cells that lost the ability to replicate.
4. d) Viruses were present when the first primordial cells evolved.
5. e) Viruses arose from fragmented DNA in a cell.

 

Answer: b

 

Difficulty: Medium

Learning Objective: LO 5.2 Explain the various hypotheses regarding the origins of viruses and the evidence for each.

Section Reference: Section 5.2 Origins of viruses

 

 

19) Which of these findings supports the progressive hypothesis of viral origin?

 

1. a) The presence of mitochondria and chloroplast in cells.
2. b) The existence of obligate intracellular pathogens like Chlamydia.
3. c) The discovery of nucleocytoplasmic large DNA viruses.
4. d) The existence of eukaryal transposons or retrotransposon genetic elements.
5. e) The presence of a nucleus in eukaryotic cells.

 

Answer: d

 

Difficulty: Medium

Learning Objective: LO 5.2 Explain the various hypotheses regarding the origins of viruses and the evidence for each.

Section Reference: Section 5.2 Origins of viruses

 

 

20) What technique is usually used for the quantification of a bacteriophage suspension?

 

1. a) a direct count
2. b) a plaque assay
3. c) a protein-based assay
4. d) a loop dilution assay
5. e) a PCR assay

 

Answer: b

 

Difficulty: Easy

Learning Objective: LO 5.3 Describe the methods used to replicate and observe viruses in the research laboratory.

Section Reference: Section 5.3 Cultivation, purification, and quantification of viruses

 

 

21) The term for bacteriophage DNA that has integrated into the host cell chromosome and replicates along with the host cell chromosome.

 

1. a) a plasmid
2. b) a transposon
3. c) a prophage
4. d) a lysogen
5. e) a retrophage

 

Answer: c

 

Difficulty: Easy

Learning Objective: LO 5.3 Describe the methods used to replicate and observe viruses in the research laboratory.

Section Reference: Section 5.3 Cultivation, purification, and quantification of viruses

 

 

22) Term for bacteriophages that have the ability to either cause a lytic infection or integrate their genome into the host cell chromosome after entry into the host cell.

 

1. a) lysogenic phage
2. b) virulent phage
3. c) transposable phage
4. d) cytopathic phage
5. e) retro-phage

 

Answer: a

 

Difficulty: Easy

Learning Objective: LO 5.3 Describe the methods used to replicate and observe viruses in the research laboratory.

Section Reference: Section 5.3 Cultivation, purification, and quantification of viruses

 

 

23) All of the following methods can be used to quantify viruses EXCEPT:

 

1. a) plaque assay.
2. b) hemagglutinin assay.
3. c) viral protein assay.
4. d) endpoint assay to determine LD₅₀.
5. e) endpoint assay to determine ID₅₀.

 

Answer: c

 

Difficulty: Medium

Learning Objective: LO 5.3 Describe the methods used to replicate and observe viruses in the research laboratory.

Section Reference: Section 5.3 Cultivation, purification, and quantification of viruses

 

 

24) The International Committee on Taxonomy of Viruses (ICTV) classification scheme uses all of the following criteria to classify viruses EXCEPT:

 

1. a) the host they infect.
2. b) the type of nucleic acid they contain.
3. c) ribosomal RNA sequence.
4. d) virion morphology.
5. e) presence of absence of an envelope.

 

Answer: c

 

Difficulty: Easy

Learning Objective: LO 5.4 Describe the various methods used to classify and name viruses.

Section Reference: Section 5.4 Diversity of viruses

 

 

25) Which Domain contains the viruses?

 

1. a) Bacteria
2. b) Archaea
3. c) Eukarya
4. d) It depends upon their host.
5. e) They are not classified at the domain level.

 

Answer: e

 

Difficulty: Easy

Learning Objective: LO 5.4 Describe the various methods used to classify and name viruses.

Section Reference: Section 5.4 Diversity of viruses

 

 

26) What is the Baltimore classification scheme for viruses based on?

 

1. a) strandedness and type of nucleic acid
2. b) type of virion symmetry
3. c) type of capsid found in the virion
4. d) type of host the virus infects
5. e) the presence or absence of an envelope

 

Answer: a

 

Difficulty: Easy

Learning Objective: LO 5.4 Describe the various methods used to classify and name viruses.

Section Reference: Section 5.4 Diversity of viruses

 

 

27) Which method listed below would provide the most reliable information for the identification of an unknown virus?

 

1. a) electron microscopy
2. b) hemagglutinin assay
3. c) plaque assay
4. d) antibody titer assay
5. e) viral nucleic acid analysis

 

Answer: e

 

Difficulty: Easy

Learning Objective: LO 5.4 Describe the various methods used to classify and name viruses.

Section Reference: Section 5.4 Diversity of viruses

 

 

28) Viroids are infectious RNA particles that cause infections in:

 

1. a) plants and animals.
2. b) animals.
3. c) bacteria and plants.
4. d) plants
5. e) bacteria.

 

Answer: c

 

Difficulty: Easy

Learning Objective: LO 5.5 Define the following terms: viroid, satellite virus, satellite RNA, prion, transmissible spongiform encephalopathy.

Section Reference: Section 5.5 Virus-like particles

 

 

29) Why is the human hepatitis delta virus similar to satellite viruses of plants?

 

1. a) It has a similar nucleic acid sequence.
2. b) It can also cause an infection in plants.
3. c) It requires a helper virus for replication in the cell.
4. d) It is a single-stranded DNA virus.
5. e) It is related to the retroviruses.

 

Answer: c

 

Difficulty: Easy

Learning Objective: LO 5.5 Define the following terms: viroid, satellite virus, satellite RNA, prion, transmissible spongiform encephalopathy.

Section Reference: Section 5.5 Virus-like particles

 

 

30) What is a prion?

 

1. a) An infectious RNA particle.
2. b) A particle similar to a satellite virus.
3. c) An infectious DNA particle.
4. d) An infectious protein particle.
5. e) A type of virus.

 

Answer: d

 

Difficulty: Easy

Learning Objective: LO 5.5 Define the following terms: viroid, satellite virus, satellite RNA, prion, transmissible spongiform encephalopathy.

Section Reference: Section 5.5 Virus-like particles

 

 

31) Which of these causes transmissible spongiform encephalopathies?

 

1. a) viroids
2. b) satellite viruses
3. c) the human delta virus
4. d) prions
5. e) satellite RNAs

 

Answer: d

 

Difficulty: Easy

Learning Objective: LO 5.5 Define the following terms: viroid, satellite virus, satellite RNA, prion, transmissible spongiform encephalopathy.

Section Reference: Section 5.5 Virus-like particles

 

 

32) How do prions cause disease?

 

1. a) By corrupting mRNA expression in the cell.
2. b) By corrupting DNA replication in the cell.
3. c) By preventing translation from occurring in the cell.
4. d) By causing naturally occurring proteins in the cell to change shape.
5. e) By preventing proper RNA transcription termination.

 

Answer: d

 

Difficulty: Easy

Learning Objective: LO 5.5 Define the following terms: viroid, satellite virus, satellite RNA, prion, transmissible spongiform encephalopathy.

Section Reference: Section 5.5 Virus-like particles

 

 

33) The discovery of oncogenes in this virus group led to the discovery of proto-oncogenes in human cells and an understanding of how tumors form.

 

1. a) Poliovirus
2. b) Retrovirus
3. c) Rhinovirus
4. d) Orthomyxovirus
5. e) Paramyxovirus

 

Answer: b

 

Difficulty: Easy

Learning Objective: LO 5.6 Describe the laboratory methods that utilize the unique properties of virus as tools for research.

Section Reference: Section 5.6 Virology today

 

 

34) What do proto-oncogenes encode?

 

1. a) proteins that cause cell death
2. b) proteins that cause apoptosis in the cell
3. c) proteins that control cell division
4. d) proteins that prevent virus infection
5. e) retroviral proteins

 

Answer: c

 

Difficulty: Medium

Learning Objective: LO 5.6 Describe the laboratory methods that utilize the unique properties of virus as tools for research.

Section Reference: Section 5.6 Virology today

 

 

35 Gene therapy technologies may use viruses:

 

1. a) to destroy cells that are not functioning normally.
2. b) as gene-carrying vectors for delivery to target cells.
3. c) to cause cytopathic effects in certain cells.
4. d) to stimulate cell destruction by the immune system.
5. e) to cause disease and thus boost the immune system.

 

Answer: b

 

Difficulty: Easy

Learning Objective: LO 5.6 Describe the laboratory methods that utilize the unique properties of virus as tools for research.

Section Reference: Section 5.6 Virology today

 

 

Question Type: True/False

 

 

36) All viruses require host cell enzymes for translation.

 

Answer: True

 

Difficulty: Easy

Learning Objective: LO 5.1 Explain the unique properties of viruses and how they are categorized.

Section Reference: Section 5.1 A basic overview of viruses

 

 

37) Enveloped viruses acquire their envelope from host cell membranes.

 

Answer: True

 

Difficulty: Easy

Learning Objective: LO 5.1 Explain the unique properties of viruses and how they are categorized.

Section Reference: Section 5.1 A basic overview of viruses

 

 

38) Filtration of a bacteriophage preparation replicated in E. coli will effectively separate viable cells from phage particles.

 

Answer: True

 

Difficulty: Easy

Learning Objective: LO 5.3 Describe the methods used to replicate and observe viruses in the research laboratory.

Section Reference: Section 5.3 Cultivation, purification, and quantification of viruses

 

 

39) Electron microscopy is the most precise way to identify an unknown virus.

 

Answer: False

 

Difficulty: Easy

Learning Objective: LO 5.4 Describe the various methods used to classify and name viruses.

Section Reference: Section 5.4 Diversity of viruses

 

 

40) All viruses that cause hepatitis in humans belong to the same virus family.

 

Answer: False

 

Difficulty: Easy

Learning Objective: LO 5.4 Describe the various methods used to classify and name viruses.

Section Reference: Section 5.4 Diversity of viruses

 

 

41) Viruses have been used extensively to further our knowledge on the molecular biology of the human cell.

 

Answer: True

 

Difficulty: Easy

Learning Objective: LO 5.6 Describe the laboratory methods that utilize the unique properties of virus as tools for research.

Section Reference: Section 5.6 Virology today

 

 

42) Viruses are currently being used for gene therapy as the agent for delivery of the gene to the appropriate cell.

 

Answer: True

 

Difficulty: Easy

Learning Objective: LO 5.6 Describe the laboratory methods that utilize the unique properties of virus as tools for research.

Section Reference: Section 5.6 Virology today

 

 

Question Type: Text Entry

 

 

43) A bacterial strain that contains a phage genome integrated into its chromosome is called a _________.

 

Answer: lysogen

 

Difficulty: Easy

Learning Objective: LO 5.3 Describe the methods used to replicate and observe viruses in the research laboratory.

Section Reference: Section 5.3 Cultivation, purification, and quantification of viruses

 

 

44) The zone of clearing as a result of a phage infection on a lawn of E. coli growing on the surface of an agar plate is called a ________.

 

Answer: plaque

 

Difficulty: Easy

Learning Objective: LO 5.3 Describe the methods used to replicate and observe viruses in the research laboratory.

Section Reference: Section 5.3 Cultivation, purification, and quantification of viruses

 

 

45) Small infectious RNA molecules that are able to cause disease in plants are called ________.

 

Answer: Viroids

 

Difficulty: Easy

Learning Objective: LO 5.5 Define the following terms: viroid, satellite virus, satellite RNA, prion, transmissible spongiform encephalopathy.

Section Reference: Section 5.5 Virus-like particles

 

 

46) Infectious protein particles that cause diseases like Creutzfeldt-Jakob disease are called ________.

 

Answer: prions

 

Difficulty: Easy

Learning Objective: LO 5.5 Define the following terms: viroid, satellite virus, satellite RNA, prion, transmissible spongiform encephalopathy.

Section Reference: Section 5.5 Virus-like particles

 

 

47) Genes that are involved in the normal regulation of the cell cycle and can be altered to increase probability of cancer are called ___________.

 

Answer: proto-oncogenes

 

Difficulty: Easy

Learning Objective: LO 5.6 Describe the laboratory methods that utilize the unique properties of virus as tools for research.

Section Reference: Section 5.6 Virology today

 

 

Question Type: Essay

 

 

48) Describe the coevolution hypothesis of viral origin. What evidence supports this hypothesis?

 

Answer:

 

Difficulty: Medium

Learning Objective: LO 5.2 Explain the various hypotheses regarding the origins of viruses and the evidence for each.

Section Reference: Section 5.2 Origins of viruses

Solution: This hypothesis speculates that the first viruses appeared about the same time as the first cells. The first cells may have contained self-replicating RNA enclosed by a lipid membrane; later DNA replaced the RNA as more stable genetic material. The first viruses may also have contained self-replicating RNA that entered a primordial cell and were able to use the proteins being made inside the cell to form capsids.

 

 

49) What is a prophage and how is the prophage established in a bacterial cell?

 

Answer:

 

Difficulty: Easy

Learning Objective: LO 5.3 Describe the methods used to replicate and observe viruses in the research laboratory.

Section Reference: Section 5.3 Cultivation, purification, and quantification of viruses

Solution: A prophage is the genome of a bacteriophage that has integrated into its host chromosome. Bacteriophages that can cause either a lytic infection or exist as a prophage are called temperate phages or lysogenic phages. Upon entry into an appropriate host cell the phage DNA early genes are transcribe and translated. If phage gene products that establish the lysogenic state are expressed at a faster rate than genes required for the lytic infection, the phage DNA will integrate into the host chromosome and will replicate along with the host chromosome. Bacterial strains that contain phage genomes are referred to as lysogens.

 

 

50) The ICTV virus classification scheme uses a number of viral attributes for the grouping of viruses into orders, families, genera, and species. List the viral features used to classify viruses using this scheme.

 

Answer:

 

Difficulty: Easy

Learning Objective: LO 5.3 Describe the methods used to replicate and observe viruses in the research laboratory.

Section Reference: Section 5.3 Cultivation, purification, and quantification of viruses

Solution: The morphology of the virus is considered; size, presence or absence of an envelope, and shape (icosahedral, helical symmetry, complex symmetry). The type of viral nucleic acid; (-)ssRNA, (+)ssRNA, dsRNA, dsDNA, ssDNA. Biological features of the virus, such as host range, replication strategies, and pathogenicity are considered.