STEP IN THE PCR CYCLE WHERE NUCLEOTIDES ARE USED

Nucleotides are used during the extension step of the polymerase chain reaction (PCR) cycle.

During the extension step, the polymerase enzyme extends the growing DNA strand by adding nucleotides to the 3’ end of the primer, based on the template strand. The nucleotides are added in a complementary manner, meaning that they are paired with the template nucleotides based on their base pairing rules (A-T and G-C). This process of adding nucleotides to the growing DNA strand is repeated multiple times, resulting in the amplification of the target DNA sequence.