1.What is the difference between complete medium and minimal medium? How are complete media and minimal media to which one or more nutrients have been added (selective media) used to isolate auxotrophic mutants of bacteria?

2.Briefly explain the differences between F⁺, F⁻, Hfr, and F′ cells.

3.What types of matings are possible between F⁺, F⁻, Hfr, and F′ cells? What outcomes do these matings produce? What is the role of the F factor in conjugation?

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4.Explain how interrupted conjugation, transformation, and transduction can be used to map bacterial genes. How are these methods similar and how are they different?

5.List some of the characteristics that make bacteria and viruses ideal organisms for many types of genetic studies.

6.What types of genomes do viruses have?

7.Briefly describe the differences between the lytic cycle of virulent phages and the lysogenic cycle of temperate phages.

8.Briefly explain how genes in phages are mapped.

9.Briefly describe the genetic structure of a typical retrovirus.

10.What are the evolutionary origins of HIV-1 and HIV-2?

11.Most humans are not easily infected by avian influenza. How, then, do DNA sequences from avian influenza become incorporated into human influenza?