DNA replication

• What are the three models proposed for DNA replication?

  Conservative, semi-conservative, and fragmented
• What isotopes of nitrogen were used in the experiments on DNA replication?

  N15 and N14
• What did the experiments prove about DNA replication?

  That DNA replicates through semi-conservative replication
• What is the role of helicase in DNA replication?

  • Helicase is an enzyme
  • It unwinds the DNA
  • It breaks hydrogen bonds between the strands
• What happens after helicase unwinds the DNA during replication?

  Free nucleotides are added
• What is the function of DNA polymerase in DNA replication?

  DNA polymerase joins free nucleotides
• What are the key steps in the process of DNA replication?

  1. Helicase unwinds the DNA
  2. Hydrogen bonds are broken
  3. Free nucleotides are added
  4. DNA polymerase joins free nucleotides