When are dntps used in the polymerase chain reaction

dATP, dTTP, dGTP and dTTP are four common dNTPs used in PCR. The function of dNTPs in PCR is to expand the growing DNA strand with the help of Taq DNA polymerase. It binds with the complementary DNA strand by hydrogen bonds. The PCR is an in vitro technique of DNA synthesis.

Explanation:

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answer; i believe that the correct answer is (light);

a- all cells come from pre-existing cells