replication

• preparing template for new DNA strands?

  • DNA helix unwinds using enzyme DNA helicase
  • hydrogen bonds break between bases, 2 strands separate
  • templates ready, allowing nucleotides to line up and form complementary base pairs
• what does DNA polymerase do?

  links adjacent nucleotides to form complementary strand, phosphodiester bonds forming in condensation reactions.

  • each strand acts as a template where new strand is built
  • DNA ligase helps close gaps that have been missed
• what is the result?

  2 new DNA molecules formed and are identical to each other and the original DNA molecule
• semi conservative replication?

  each of 2 new strand DNA molecules made contain one original strand and one new strand