describe the principle of the universal genetic code in which different triplets of DNA bases either code for specific amino acids or correspond to start and stop codons

describe the semi-conservative replication of DNA during the S phase of the cell cycle, including: • the roles of DNA polymerase and DNA ligase (knowledge of other enzymes in DNA replication in cells and different types of DNA polymerase is not expected) • the differences between leading strand and lagging strand replication as a consequence of DNA polymerase adding nucleotides only in a 5’ to 3’ direction