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Microorganisms: Viruses

Microorganisms: Viruses

Microorganisms: Viruses: Shmoopvirus is Infectious True or False

1. Which of the following is NOT involved in any type of virus membrane fusion? -> Cell receptor
2. If you treat a cell with a membrane-impermeable protease and then add a virus to it, the cell will not be infected. Why not? -> The protease removes the virus receptor from the cell.
3. What does the previous answer tell you about the virus? -> The virus requires a cellular receptor to enter the cell.
4. How can you prove that a virus does NOT require low pH to enter a cell? -> Mix infected cells with uninfected cells
5. Reoviruses will still infect cells if treated with SDS, a harsh detergent that dissolves lipid bilayers. What does this information tell you about reoviruses? -> Reoviruses do not have an envelope.
6. If you infect cells with influenza virus, you can collect virus from the cells in 6 hours, but no cell death is seen. What does this information tell you? -> The strain is H1N1.
7. A team of scientists have found that the site of replication of Shmoopvirus is in the cytoplasm. What does this tell you about the genes encoded in the Shmoopvirus genome? -> Shmoopvirus is an enveloped virus.
8. Which of the following viruses would be LEAST affected if you knocked out the host RNA polymerase genes? -> dsDNA virus
9. Which of the following viruses would be the MOST affected if you knocked out the host DNA polymerase genes? -> None would be affected
10. If you counted 127 plaques in a cell culture dish after you diluted the infected sample 1:100,000 and added 0.1 mL to cells, what is the virus titre? -> 2.54 × 108 pfu/mL