1.    What experimental evidence led scientists to believe that the genetic information is encoded within DNA?   Be familiar with the classic experiments carried out by Griffith, Avery, and Hershey and Chase which led to the conclusion that DNA rather than protein serves as the carrier of genetic information.

2.    What experiments led to an understanding of the structure of the DNA molecule?  Discuss the contributions made by Chargaff, Wilkins, Franklin, and Watson and Crick.

3.    Describe the molecular structure of the DNA molecule in detail (i.e. the Watson and Crick Model).  What forms the “backbone” of the molecule?  What is responsible for holding the two strands of the double helix together?  What do we mean by antiparallel strands?  Why (chemically) do the base pairs pair as they do (i.e. adenine with thymine and guanine with cytosine)?

4.    Describe in detail the process of DNA replication.

• Is DNA replication conservative or semi-conservative? Discuss the experimental evidence that was performed to suggest that DNA replication is semiconservative.
• Discuss the functions of the various enzymes involved in replication (DNA polymerases, nucleases, primases, DNA ligase, helicases).
• How does elongation of the new strand occur?  In what direction does DNA replication occur (i.e. 5’ to 3’ or 3’ to 5’ on the growing strand)?
• How is DNA replication on the leading strand different from that on the lagging strand?
• What is DNA priming?  Compare priming on the leading strand and the lagging strand.
• Where does the energy come from to add new nucleotides to the growing strand in replication?
• Why is DNA replication such an accurate process?  How does proof-reading of the DNA molecule take place?  How is damaged DNA repaired?
• What do we call it when an uncorrected error that occurs duing DNA replication?