Which of the following is a correct sequence of steps in a PCR (Polymerase Chain Reaction) ?

Options

A. Denaturation, Extension, Annealing
B. Extension, Denaturation, Annealing
C. Annealing, Denaturation, Extension
D. Denaturation, Annealing, Extension

Answer

D

Explanation

• The first step in the polymerase chain reaction is denaturation during which strands of dsDNA separate. This requires temperature around `94^@C`.
• This is followed by annealing in which primers anneal to 3. end of template DNA strand.
• Annealing is followed by extension in which Taq polymerase adds nucleotides to 3.OH end of primers.