Question 1

Which of the following best describes why viruses are not considered 'alive' in the traditional sense?

Accepted Answer

They lack the machinery for protein synthesis and must use a host cell to replicate.

Question 2

A virus with a helical capsid structure is most likely to have which of the following arrangements?

Accepted Answer

Capsomeres forming a continuous spiral around the nucleic acid.

Question 3

Which of the following statements about viral genomes is correct?

Accepted Answer

Viruses may have single-stranded or double-stranded DNA or RNA, but never both types of nucleic acid.

Question 4

What is the primary function of viral spikes (glycoproteins) on the surface of a virus?

Accepted Answer

To attach specifically to host cell receptors and facilitate entry.

Question 5

Which of the following best explains why antiviral drugs are more difficult to design than antibacterial drugs?

Accepted Answer

Viruses have a high mutation rate and use host cell machinery for replication.

Question 6

A scientist observes a virus that can only infect liver cells in humans. This is an example of:

Accepted Answer

Restricted host range

Question 7

Which of the following is a correct sequence of events in the multiplication cycle of an animal virus?

Accepted Answer

Adsorption → Penetration → Uncoating → Synthesis → Assembly → Release

Question 8

Which of the following is a cytopathic effect (CPE) that may be observed in virus-infected cells?

Accepted Answer

Formation of inclusion bodies in the cytoplasm or nucleus

Question 9

A bacteriophage that integrates its DNA into the host bacterial chromosome and remains dormant is in which state?

Accepted Answer

Prophage state (lysogeny)

Question 10

Which of the following is a unique property of prions compared to viruses?

Accepted Answer

They are composed solely of protein and lack nucleic acids.

Question 11

Which of the following best describes lysogenic conversion?

Accepted Answer

A bacterium acquires a new trait from a temperate phage, such as toxin production.

Question 12

Which of the following laboratory methods is most commonly used to cultivate animal viruses for vaccine production?

Accepted Answer

Inoculation of embryonated bird eggs

Question 13

Which of the following is true regarding the Baltimore classification system for viruses?

Accepted Answer

It classifies viruses based on their nucleic acid type and replication strategy.

Question 14

A virus with a positive-sense single-stranded RNA genome can:

Accepted Answer

Be immediately translated by host ribosomes into viral proteins.

Question 15

Which of the following is NOT a typical component of a virus particle?

Accepted Answer

Ribosomes

Question 16

Which of the following best explains why antibiotics are ineffective against viral infections?

Accepted Answer

Viruses lack cell walls and metabolic pathways targeted by antibiotics.

Question 17

Which of the following is a real-world example of lysogenic conversion affecting human health?

Accepted Answer

The production of diphtheria toxin by Corynebacterium diphtheriae due to a prophage.

Question 18

Which of the following statements about viroids is correct?

Accepted Answer

Viroids are naked strands of RNA that infect plants.

Question 19

Which of the following is the correct notation for a virus family name?

Accepted Answer

Herpesviridae

Question 20

A scientist is studying a virus that requires a helper virus to replicate. This virus is best classified as a:

Accepted Answer

Satellite virus

Chapter 7:Viruses and Prions: Structure, Classification, and Multiplication- Book Notes

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