Chapter 6: Microbiology Pearson

In the Spring of 2009, a novel H1N1 virus emerged that had a new combination of genes from pigs, humans, and birds. As a result, the virus spread quickly, resulting in a swine flu pandemic. Which of the following concepts explains why the outbreak occurred?

Antigenic shift.

Compared to both prokaryotic and eukaryotic cells, viruses?

Are generally smaller.

In which stage does formation of mature viruses occur? (#9)

Assembly.

Which stage of animal virus replication may be blocked by a drug that binds with the viral spike?

Attatchment.

Which of the following names represents a viral order?

Mononegravirales.

The host DNA is usually degraded during which stage? (#9)

Biosynthesis.

Which of the following is (are) used to classify viruses? To be marked correct, you'll need to select all applicable statements, as there may be more than one correct answer.

-Capsid symmetry. -Type of nucleic acid present.

Which of the following genome types has been observed in viruses? To be marked correct, you'll need to select all true statements, as there may be more than one correct answer.

-Single-stranded DNA. -Double-stranded RNA. -Single-stranded RNA.

Which of the following are ways that viruses differ from prokaryotes and eukaryotes? To be marked correct, you'll need to select all true statements, as there may be more than one correct answer.

-Unlike prokaryotes and eukaryotes, viruses are classified as acellular particles. -Unlike prokaryotes and eukaryotes, viruses are incapable of replicating independently from a host cell. -Unlike prokaryotes and eukaryotes, viruses are not considered alive.

In what year did Stanley Prusiner discover prions? (#10)

1982.

Lysogenic viral DNA which has integrated into the host genome is referred to as? (#8)

A prophage.

Viral spikes?

Allow the virus to attach and enter host cells, may be a target for the host immune system, and show specificity in binding to particular structures on the host cell.

Retroviruses use the enzyme reverse transcriptase to?

Direct the production of DNA from a single-stranded RNA genome.

Which of the following events might trigger induction of a temperate bacteriophage? (#8)

Exposure to UV light.

Your patient has purple, red, and brown lesions on the legs, indicative of Kaposi sarcoma. Given this observation, which of the following oncogenic viruses is most likely present in your patient?

Human herpes virus-8.

Which of the following is an example of phage conversion?

Infection of Streptococcus pyogenes with T12 phage enables the bacteria to produce erythrogenic toxins, allowing it to cause scarlet fever.

What is the fate of the prophage during the lysogenic stage? (#8)

It is copied every time the host DNA replicates.

When a virus has an envelope,

It likely escapes its host cell by budding.

A nurse experienced an accidental needle stick while treating a patient who has hepatitis C. The seroconversion window for hepatitis C is approximately 6-8 weeks. Given this information, which of the following viral detection methods would be most appropriate for detecting a hepatitis C infection in the nurse one week following the needle stick?

PCR-based detection of hepatitis C RNA.

In which stage is the viral DNA introduced into the cell? (#9)

Penetration.

From which phrase is the term "prions" derived? (#10)

Proteinaceous infectious particles.

Which stage of animal virus replication will not be different between naked viruses and enveloped viruses?

Replication.

Which disease did Stanley Prusiner first identify as being caused by prions? (#10)

Scrapie.

How is the lytic cycle different from the lysogenic cycle with respect to the infected host cell? (#8)

The host cell dies during the lytic stage.

You observe that a novel virus penetrates the host cell through membrane fusion. Which of the following statements must also be true regarding this virus and its replicative cycle?

The virus releases from host cells by budding.

What would be the fate of a lytic bacteriophage if the host cell died prior to the assembly stage?

The virus would not be able to infect new hosts.

How are prions different from other infectious agents? (#10)

They lack nucleic acid.

The number of species that a specific virus infects is called its host range while the types of tissues that the virus infects is called tropism.

True.

Which of the following prion diseases may be acquired by eating beef contaminated with a cattle prion?

Variant CJD.