Q: A virus is classified as a member of the family Flaviviridae. According to the rules of viral nomenclature, what is the correct format for its species name?

$\text{Genus species}$, e.g., Orthoflavivirus zikaense

Question 1

Which of the following statements best describes why viruses are considered obligate intracellular parasites?

Accepted Answer

They can only replicate by hijacking the metabolic machinery of a living host cell.

Question 2

A virus is found to have a single-stranded RNA genome, a helical capsid, and an envelope with glycoprotein spikes. According to the Baltimore classification, to which group does this virus most likely belong?

Accepted Answer

Group IV: (+)ssRNA viruses

Question 3

Which of the following best explains why enveloped viruses are generally less stable outside the host compared to non-enveloped viruses?

Accepted Answer

Their lipid envelope is easily disrupted by environmental factors such as detergents and desiccation.

Question 4

Which of the following is NOT a function of the viral capsid?

Accepted Answer

Synthesizing viral mRNA

Question 5

A researcher isolates a virus with a 20-sided, roughly spherical protein shell. Which term best describes the symmetry of this virus?

Accepted Answer

Icosahedral

Question 6

Which of the following statements about viral genomes is correct?

Accepted Answer

A virus can have either DNA or RNA as its genetic material, but never both.

Question 7

A patient is treated with bacteriophage therapy for a drug-resistant bacterial infection. Which property of bacteriophages makes them suitable for this application?

Accepted Answer

They specifically infect and lyse bacterial cells without harming human cells.

Question 8

Which of the following best describes the role of glycoprotein spikes on the surface of enveloped viruses?

Accepted Answer

They mediate attachment to specific host cell receptors, facilitating viral entry.

Question 9

A virus is classified as a member of the family Flaviviridae. According to the rules of viral nomenclature, what is the correct format for its species name?

Accepted Answer

$	ext{Genus species}$, e.g., Orthoflavivirus zikaense

Question 10

Which of the following scenarios best illustrates the concept of a virome?

Accepted Answer

The total collection of viruses present on human skin, influencing both health and disease states.

Question 11

A newly discovered virus infects aquatic organisms and is found to influence the diversity and evolution of its ecosystem. Which term best describes the collective viral community in this environment?

Accepted Answer

Aquatic virome

Question 12

Which of the following is a key advantage of the Baltimore classification system for viruses?

Accepted Answer

It groups viruses based on their type of nucleic acid and mRNA synthesis strategy.

Question 13

A virus with a double-stranded DNA genome and an icosahedral capsid is discovered. According to the Baltimore classification, which group does it belong to?

Accepted Answer

Group I

Question 14

Which of the following best describes the function of a virion?

Accepted Answer

It is the fully assembled, infectious form of a virus particle that exists outside a host cell.

Question 15

Which of the following is a plausible reason why viruses are not considered living organisms?

Accepted Answer

They lack cellular structure and cannot carry out metabolism independently.

Question 16

A virus is found to have a segmented, double-stranded RNA genome. Which Baltimore group does it belong to, and what is a key implication for its replication?

Accepted Answer

Group III; it must carry its own RNA-dependent RNA polymerase to synthesize mRNA.

Question 17

Which of the following best explains the importance of standardized virus nomenclature?

Accepted Answer

It ensures global consistency and clarity in scientific communication, diagnostics, and public health.

Question 18

A virus with a complex capsid structure and a tail fiber is most likely to infect which type of host?

Accepted Answer

Bacteria

Question 19

Which of the following statements about the human virome is correct?

Accepted Answer

Viral communities present on the skin may influence both healthy and disease states in humans.

Question 20

A newly discovered virus has a helical capsid, RNA genome, and an outer lipid layer with spike proteins. Predict its likely mode of entry into host cells and discuss how its architecture might influence vaccine development.

Accepted Answer

It likely enters host cells via membrane fusion mediated by spike proteins; the presence of spike proteins makes them good targets for neutralizing antibodies in vaccine design.

Viruses: Structure, Classification, and Impact in Microbiology

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