DNA replication is semi-conservative; new DNA molecule is composed of 1 old strand of DNA and 1 new strand .Many enzymes are involved in this process. The action of these can be combined into a 7 step process:1) DNA Helicase --> breaks the H bonds between Nitrogen bases --> unwinds DNA molecule2) DNA Gyrase --> ensures that the strain from the unwinding is relieved3) Single stranded binding proteins --> attach to each of the strands and prevent them from rewinding back4) DNA Primase --> attaches short segment of RNA nucelotides (=RNA primer) to beginning of complimentary strand, it in a way 'paves the path for Polymerases that will act after', different action in leading and lagging strand 5) DNA Polymerase III --> adds DNA nucloetides from 5' to 3' - complementary base pairing (A-T, G-C), on leading strand = continuous, lagging strand = discontinuous (this is because DNA is antiparallel) ---> attaches to 3' end of the RNA primer6) DNA Polymerase I --> removes RNA primer and replaces it with complimentary DNA nucleotides7) DNA Ligase --> joins sugar phosphate backbone of (mostly) lagging strand