Define the term 'semi-conservative DNA replication' and explain the process of DNA replication. (6 marks)

Semi-conservative replication: Each strand of the original (double stranded) DNA molecule acts as a template for new strand synthesis, resulting in two molecules of DNA, each containing one original (parental) strand and one newly synthesised strand. (2 marks)Process: Enzyme DNA helicase breaks the H-bonds between the base pairs, separating the double helix strands. Enzyme DNA polymerase uses single stranded DNA as a template and catalyses the formation of a new complementary DNA strand using surrounding free DNA nucleotides. (4 marks )