Q: Which equation best represents the basic structure of a naked capsid virus?

$$\text{DNA or RNA} + \text{Capsid Protein} \rightarrow \text{Nucleocapsid}$$

Question 1

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

Accepted Answer

Viruses are composed of proteins and nucleic acids but lack organelles and metabolism.

Question 2

A scientist discovers a virus with a capsid composed of 20 faces, each an equilateral triangle, and 60 identical protein subunits. What type of symmetry does this virus exhibit?

Accepted Answer

Icosahedral symmetry

Question 3

Which step in the lytic cycle is responsible for the biosynthesis of new viral proteins and nucleic acids using host cell machinery?

Accepted Answer

Replication

Question 4

A virus is found to have a lipid envelope surrounding its capsid. Which statement is TRUE regarding the origin of this envelope?

Accepted Answer

The envelope is derived from the host cell membrane during viral budding.

Question 5

Which of the following is NOT encoded in a typical viral genome?

Accepted Answer

Genes for complete protein synthesis machinery

Question 6

A patient presents with shingles years after recovering from chickenpox. Which viral property explains this phenomenon?

Accepted Answer

Latency of Varicella zoster virus in nervous system tissues

Question 7

Which of the following best describes the process of zoonosis in the context of emerging viruses?

Accepted Answer

Transmission of a virus from animals to humans, potentially leading to new human infections

Question 8

During the lytic cycle, what is the expected outcome for the host cell after the release of new viral particles?

Accepted Answer

The host cell undergoes lysis and dies.

Question 9

Which of the following factors has contributed to the increased emergence of new viruses in human populations?

Accepted Answer

Human population growth and ecological changes

Question 10

A virus with a capsid that is neither purely helical nor purely icosahedral, and possesses additional structures such as protein tails, is best classified as:

Accepted Answer

Complex virus

Question 11

Which equation best represents the basic structure of a naked capsid virus?

Accepted Answer

$$	ext{DNA or RNA} + 	ext{Capsid Protein} ightarrow 	ext{Nucleocapsid}$$

Question 12

Which of the following viruses is an example of a bacteriophage?

Accepted Answer

A virus that infects bacteria

Question 13

What is the main difference between the lytic and lysogenic cycles of bacteriophage infection?

Accepted Answer

Lytic cycle results in host cell lysis and release of new viruses, while lysogenic cycle involves integration of viral DNA into host genome without immediate lysis.

Question 14

Which of the following is a plausible reason why giant viruses are structurally unique compared to other viruses?

Accepted Answer

They may be large enough to be visible with a light microscope and possess complex capsids.

Question 15

Which of the following is NOT a typical method by which viruses are classified?

Accepted Answer

By their metabolic activity

Question 16

A researcher observes a virus with a long, tube-like capsid structure. Which type of capsid symmetry does this virus most likely possess?

Accepted Answer

Helical symmetry

Question 17

Which of the following best describes the role of capsomeres in viral structure?

Accepted Answer

Capsomeres are protein subunits that assemble to form the capsid.

Question 18

Which of the following scenarios best illustrates viral latency in eukaryotes?

Accepted Answer

Herpes simplex virus remains dormant in nervous tissue and can reactivate years later.

Question 19

Which of the following ecological or anthropogenic activities is most likely to promote the emergence of new viruses?

Accepted Answer

Deforestation and increased human-animal contact

Question 20

A virus with a circular, double-stranded DNA genome is most likely to be classified as which type?

Accepted Answer

Baculovirus

6-Viruses: Structure, Classification, and Infection Cycles

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