DNA

When a cell divides it needs to make identical copies of the DNA

Steps

- The double helix is untwisted by the enzyme DNAhelicase 

- The hyrdogen bonds holding the complementary base pairs are broken, allowing the two strands to unzip and expose the nucleotide bases

- Each strand acts as a templete 

- Free complentary nucleotide bases floating in the nucleus hydrogen bond to the exposed bases

- Covalent bonds are formed between the bases to join the sugar phosphate backbone using the enzyme DNApolymerse