Question 1

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

Accepted Answer

Viruses lack cellular structure and cannot carry out all life processes independently.

Question 2

A scientist discovers a new infectious agent that consists only of naked RNA and infects plants. What is this agent most likely classified as?

Accepted Answer

Viroid

Question 3

Which structural component of a virus provides protection for viral nucleic acids and is made of protein subunits called capsomeres?

Accepted Answer

Capsid

Question 4

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

Accepted Answer

Biosynthesis

Question 5

Which of the following best describes the envelope of a virus?

Accepted Answer

A lipid bilayer acquired from the host cell, containing viral glycoproteins.

Question 6

A virus with a hollow, cylindrical capsid is classified as which type?

Accepted Answer

Helical virus

Question 7

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

Accepted Answer

Attachment → Penetration → Biosynthesis → Assembly and Maturation → Release

Question 8

Which process allows enveloped viruses to exit the host cell without immediately killing it?

Accepted Answer

Budding

Question 9

What is the role of viral glycoproteins found in the envelope?

Accepted Answer

They facilitate host cell recognition and penetration.

Question 10

Which of the following viruses is an example of a negative-sense single-stranded RNA virus with a helical, enveloped structure?

Accepted Answer

Rabies virus

Question 11

A patient presents with a maculopapular rash and Koplik's spots. Which virus is most likely responsible for these symptoms?

Accepted Answer

Measles virus (Morbillivirus)

Question 12

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

Accepted Answer

Maculopapular (flat to slightly raised colored bumps)

Question 13

Why is measles highly contagious among humans?

Accepted Answer

It is transmitted via respiratory droplets and humans are the only host.

Question 14

Which of the following best describes viral latency?

Accepted Answer

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

Question 15

Which of the following is true about prions?

Accepted Answer

They are proteinaceous infectious particles that lack nucleic acids.

Question 16

Which step in the viral replication cycle is responsible for the formation of new infectious viral particles?

Accepted Answer

Assembly and Maturation

Question 17

Which of the following is a correct description of a virion?

Accepted Answer

A virus outside of a cell, consisting of a capsid surrounding a nucleic acid core.

Question 18

Which of the following best explains the function of hemagglutinin in the measles virus?

Accepted Answer

It attaches to receptors on host epithelial cells, facilitating viral entry.

Question 19

Which treatment is used to inhibit viral DNA polymerases in measles infection, and what is its mechanism?

Accepted Answer

Ribavirin; it is a guanosine analogue that prevents the virus from copying its genome.

Question 20

Which of the following equations correctly represents the composition of a nucleocapsid?

Accepted Answer

$$	ext{Nucleic acid} + 	ext{Capsid}$$

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

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