1. Why is the synthesis of mRNA a central issue for all viruses?

2. Polio and HIV are both +ssRNA viruses that have very different strategies for replicating their genomes. After the viral genomes enter the cell (ie. post entry), describe the first step involved in replication of each genome. Your description can include a diagram and should cover 1) the name of the synthesis reaction that takes place, 2) any molecules that act on the viral genome 3) whether these molecules are viral or host in origin, 4) the product(s) of this first step, and 5) which cellular compartment step 1 takes place in.

3. What is cap stealing and why is it necessary for influenza replication?

4. A-C. Your roommate spends the night in the bathroom being rather ill. Motivated more by curiosity than common sense, you take a sample from the relevant location (you are very good friends with your roommate!) and make an extract. When this extract is applied to human cells in culture, you see the formation of plaques (indicating that the cells have died and lysed). You extract nucleic acid from the plaques and determine that it is 1 long continuous piece. When this is added to a mixture containing ribosomes and all the necessary components to synthesize proteins, you detect several proteins.

A. Of the classes of Viruses that we talked about, which kind of virus is this most likely to be. Provide reason(s) for your answer.

B. How can several proteins be made from the above nucleic acid (ie you only saw 1 long piece).

C. What does this imply about the activity of at least one of the proteins that are synthesized?