DNA replication takes place in a semi-conservative manner, where each of the DNA strands serves as a template for the formation of a new strand. This ensures genetic continuity between generations, as genetic information is passed on from one generation to the next.
The mechanism of DNA replication is as following. Firstly, the double helix unwinds and hydrogen bonds between the complementary bases are broken using DNA helicase. This separates the two strands of DNA. Subsequently, each strand is used as a template, and complementary base pairing via hydrogen bonds occurs between the template strand and free nucleotides. Finally, adjacent nucleotides are joined together by phosphodiester bonds in a condensation reaction catalysed by DNA polymerase. This completes the synthesis of a new DNA molecule.