Dental Admissions Test (DAT) 2025 – 400 Free Practice Questions to Pass the Exam

During DNA replication, the enzyme responsible for adding new nucleotides to the growing DNA strand is DNA polymerase. Helicase is incorrect because its main function is to unwind the parent DNA strand. Ligase is incorrect because its main function is to join the small fragments of DNA into a single strand. Primase is incorrect because its main function is to synthesize RNA primers that are needed for DNA polymerase to start adding new nucleotides. Therefore, DNA polymerase is the only enzyme that specifically adds new nucleotides to the growing DNA strand during DNA replication.