Question 1

Which of the following statements best explains why viruses are not considered living organisms?

Accepted Answer

Viruses do not perform metabolism and cannot synthesize proteins.

Question 2

A scientist discovers a new infectious agent that consists only of naked RNA and infects plants. Which category does this agent belong to?

Accepted Answer

Viroid

Question 3

Which structural component of a virus provides protection for viral nucleic acid and serves as a means of attachment to host cells?

Accepted Answer

Capsid

Question 4

During viral replication, which step involves the commandeering of host cell transcription and translation machinery to synthesize viral proteins?

Accepted Answer

Biosynthesis

Question 5

Which of the following best describes the structure of a polyhedral virus?

Accepted Answer

Capsid with geometrical sides

Question 6

A virus with an envelope acquires this structure from which source?

Accepted Answer

Host cell membrane during replication or release

Question 7

Which of the following is a correct sequence for the general replication cycle of animal viruses?

Accepted Answer

Attachment → Penetration → Biosynthesis → Assembly/Maturation → Release

Question 8

Which of the following viral diseases is characterized by a maculopapular rash and Koplik's spots?

Accepted Answer

Measles (Morbillivirus)

Question 9

What is the main function of hemagglutinin in the measles virus?

Accepted Answer

It attaches to receptors on host epithelial cells.

Question 10

Which of the following best describes viral latency?

Accepted Answer

The virus remains dormant in host cells, sometimes for years, with no viral activity, signs, or symptoms.

Question 11

Which of the following is true regarding prions?

Accepted Answer

Prions are proteinaceous infectious particles that lack nucleic acids.

Question 12

A patient presents with cold sores on the lips and blisters filled with amber fluid. Which virus is most likely responsible?

Accepted Answer

Human Herpes Virus 1 (HHV-1)

Question 13

Which of the following is a distinguishing feature of the measles rash?

Accepted Answer

Maculopapular (flat to slightly raised colored bumps)

Question 14

Which of the following best describes the role of viral glycoproteins found in the envelope?

Accepted Answer

They play an important role in host recognition and penetration.

Question 15

Which of the following is a plausible reason for the resurgence of measles in the USA after its eradication in the early 2000s?

Accepted Answer

Decrease in vaccination rates among the population

Question 16

Which of the following equations correctly represents the Central Dogma of Molecular Biology as it applies to viral biosynthesis?

Accepted Answer

$$DNA \rightarrow mRNA \rightarrow Protein$$

Question 17

Which of the following is a correct statement about the release of enveloped viruses from host cells?

Accepted Answer

They acquire their envelope by budding from the host cell membrane.

Question 18

Which of the following is a common virulence factor shared by both measles virus and herpes simplex virus?

Accepted Answer

Ability to form syncytia by fusion of host cells

Question 19

Which of the following best describes the genome of the measles virus?

Accepted Answer

Single-stranded RNA (negative sense), helical capsid, enveloped

Question 20

Which of the following is a plausible consequence of viral latency in human cells?

Accepted Answer

Permanent incorporation of viral DNA into host chromosome, leading to lifelong infection

Viruses: Structure, Replication, and Viral Diseases (Measles, Herpes)

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