Question

Why does PCR amplify DNA strands so rapidly?

• A. PCR causes DNA bases to multiply
• B. PCR includes oxidation of DNA
• C. PCR is an addition reaction
• D. PCR is an exponential reaction

Answer 1

The correct option is D PCR is an exponential reaction

PCR amplifies DNA exponentially. If there is one strand of DNA available in the beginning, it would get multiplied by 2. In subsequent reactions, the DNA keeps getting doubled. Ergo, the DNA strand increases by the power of 2. For example, if we were to do 32 rounds of PCR, the number of DNA strands would, therefore, be 2${}^{32}$, which would go into billions.