Chapter 24.5, Problem 1Q

Interpretation Introduction

Interpretation:

The number of copies of double-starnded DNA that could be present after $\text{20}$ cycles of PCR has to be predicted.

Concept introduction: PCR includes the primer mediated amplification of DNA. PCR is a technique in which DNA polymerase has ability to synthesized a new strand of DNA complementry to the offered template strand.

Primer is useful because DNA polymerase has ability to add nucleotide only onto the preexisting $\text{3'OH}$ group to add the first nucleotide.

DNA polymerase then elongates at its $\text{3'}$ end by adding more nucleotides to form extended region of dsDNA.

Number of copies of double-stranded DNA present after n number of cycles can be calculated as follows,

$\text{Number of cycles}={\text{2}}^{\text{n}}$ (1)