Question

Among the actions listed below, which are involved in PCR, and in what order?

1) Denaturation, extension, termination
2) Initiation, extension, termination
3) Initiation, denaturation, extension
4) Denaturation, annealing, extension
5) Annealing, initiation, termination

Answer 1

The correct order of steps in PCR is denaturation, annealing, and extension. These steps are repeated cyclically to amplify the DNA sequence of interest.

Step-by-step explanation:

Polymerase Chain Reaction (PCR) Steps

The Polymerase Chain Reaction (PCR) is a molecular biology technique used to amplify specific DNA sequences. The correct order of steps involved in PCR, as outlined in several informational texts, are denaturation, annealing, and extension.

First, the denaturation step involves heating the DNA to around 95°C to separate the double-stranded DNA into single strands. Second, during annealing, the temperature is lowered (usually to around 55°C) so that primers can bind to their complementary sequence on the single-stranded DNA. Finally, the extension step raises the temperature to approximately 72°C, where Taq polymerase extends the primers to form new strands of DNA. These steps are cyclically repeated to exponentially amplify the target DNA sequence.

correct sequence of steps involved in PCR is denaturation, annealing, and extension. This sequence is essential for the exponential amplification of a specific DNA segment.