Biology II

Chapter 15 Objectives

1.     Explain why researchers originally thought protein was the genetic material

  1. Summarize experiments performed by the following scientists, which provided evidence that DNA is the genetic material:

o       Frederick Griffith

o       Alfred Hershey and Martha Chase

o       Erwin Chargaff

  1. List the three components of a nucleotide
  2. Distinguish between deoxyribose and ribose
  3. List the nitrogen bases found in DNA and distinguish between pyrimidine and Purine
  4. Explain how the Watson and Crick deduced the structure of DNA and describe what evidence they used
  5. Explain the “base-pairing rule” and describe its significance
  6. Describe the structure of DNA and explain what kind of chemical bond connects the nucleotides of each strand and what type of bond holds the two strands together
  7. Explain, in their own words, semiconservative  replication and describe that Meselson-Stahl experiment
  8. Describe the process of DNA replication and explain the role of helicase, single strand binding protein, DNA polymerase, ligase and primase
  9. Explain what energy source drives endergonic synthesis of DNA
  10. Define antiparallel and explain why continuous synthesis of both DNA strands is not possible
  11. Distinguish between the leading strand and the lagging strand
  12. Explain how the lagging strand is synthesized when DNA polymerase can add nucleotides only to the 3’ end
  13. Explain the role of DNA polymerase, ligase and repair enzymes in DNA proofreading and repair