2.2 DNA Replication

2.2 DNA Replication

1. Semi Conservative

   • This ensures genetic continuity between generations of cells
     • 1) The enzyme DNA HELICASE breaks the hydrogen bonds linking the base pairs of DNA
       • 2) As a result, double helix unwinds into two strands
         • 3) Each exposed polynucleotide strand then acts as a template to which free complementary nucleotides bind to a specific base pair
           • 4) Nucleotides are joined together in a condensation reaction by DNA POLYMERASE to form 'missing' polynucleotide strand on each of the two origional polynucleotide strands of DNA
             • 5) Each of the new DNA molecules contains one of the origional DNA strands, that is, half of the origional DNA has been saved and built into each of the new DNA molecules.