Describe the process of DNA replication.

The method in which DNA replicates is called semi-conservative replication. Firstly, DNA helicase catalyses the break down of the hydrogen bonds between the base pairs in the DNA molecule. This partially unwinds the double stranded helix, so the 2 single strands are apart from eachother. These single strands act as templates for the formation of the new strands. The next step is complementary base pairing. This means that free DNA nucleotides in the nucleus are attracted to their exposed complementary base on the original template strand. A binds to T and C binds to G. The enzyme DNA polymerase then catalyses the addition of these nucleotides to the template strand, forming a double stranded helix. This happens on both template strands. The final product is 2 DNA molecules, each containing 1 strand from the original DNA molecule and 1 new strand, showing semi-conservative replication.