Bio- Chapter 17

If scientists are trying to use what they know about HSV to devise a means of protecting other people from being infected, which of the following would have the best chance of lowering the number of new cases of infection?

interference with new viral replication in preexisting cases

Which of the following is a characteristic of the lytic cycle?

a large number of viruses are released at a time

Emerging viruses arise by

all of the above

Which of the following series best reflects what we know about how the flu virus moves between species?

an animal such as a pig is infected with more than one virus, genetic recombination occurs, the new virus mutates and is passed to a new species such as a bird, and the virus mutates and can be transmitted to humans

A human pandemic is

an epidemic that extends around the world

In order to be able to remain latent in an infected live cell, HSV must be able to shut down what process?

apoptosis of a virally infected cell

Which of the following can be effective in preventing the onset of viral infection in humans?

getting vaccinated

In Figure 17.2, at the arrow marked II, what enzyme(s) are being utilized?

host cell DNA polymerase

RNA viruses require their own supply of certain enzymes because

host cells lack enzymes that can replicate the viral genome

Antiviral drugs that have become useful are usually associated with which of the following properties?

interference with viral replication

What is the function of reverse transcriptase in retroviruses?

it uses viral RNA as a template for DNA synthesis

In Figure 17.2, when new viruses are being assembled (IV), what mediates assembly?

nothing; they self-assemble

Which viruses have single-stranded RNA that acts as a template for DNA synthesis?

retroviruses

Which of the following statements describes the lysogenic cycle of a virus?

the phage DNA replicates along with the host DNA

In electron micrographs of HSV infection, it can be seen that the intact virus initially reacts with cell-surface proteoglycans, then with specific receptors. This is later followed by viral capsids docking with nuclear pores. Afterward, the capsids go from being full to "empty". Which of the following best fits these observations?

the viral envelope mediates entry into the cell, the capsid enters into the nuclear membrane, and the genome is all that enters the nucleus