Viruses 1A

All of the following statements are true EXCEPT

• In lysogenic infection, the virus replicates immediately
• Influenza virus infects humans cells
• Tobacco mosaic virus infects plant cells
• T4 bacteriophage virus infects bacteria

When researching and developing new flu vaccines, what region of the world do scientists often look to?

• Africa
• Asia
• Europe
• America
• Oceania

What do viruses depend on for their reproduction?

• A source of oxygen
• An energy source
• Living cells
• A supply of blood

How is viral reproduction different from that of cell-based organisms?

• Viruses do not require nutrients
• Viruses cannot reproduce independently
• Viruses contain their own cellular machinery
• Viruses are living organisms that survive after reproduction

Which of the following occurs during a lytic infection?

• The virus remains outside a living cell and absorbs the living cells' DNA
• The host cell is taken over by the virus over a long period of time
• Viral nucleic acid is inserted into the host cell's DNA, where it becomes a prophage
• Viral genes are quickly transcribed, and new viruses are made by the host cell

How are lytic and lysogenic infections different?

• In lysogenic infection, the virus replicates immediately
• In lysogenic infections, the virus never gains entry to the host cell
• In lysogenic infections, the virus initially persists in an inactive state within the host.
• In lysogenic infections, the virus replicates independently without the need for a living cell.

How is the structure of a virus different from the structure of a prokaryotic cell?

• Viruses are not bound by a cell membrane
• Viruses contain genetic material
• Viruses do not contain nuclei
• None of these choices

In the 1930s, American biochemist Wendell Stanley observed crystals of tobacco mosaic viruse. Based on this evidence, Stanley inferred that viruses -

• are parasites
• cause disease
• are non-living
• have nucleic acids

What structure can be found in BOTH a virus and a cell?

• Nucleic acid chain
• Golgi apparatus
• Endoplasmic reticulum
• nuclear membrane

What virus structure is similar in function to a cell membrane?

• Protein shell
• Internal protein
• Tail sheath
• End plate