What is a common method used to amplify quantities of DNA?

The Polymerase Chain Reaction (PCR) is a widely utilized method for amplifying specific sequences of DNA. This technique allows researchers to generate millions of copies of a particular DNA segment, making it possible to analyze small amounts of DNA that would otherwise be insufficient for experiments such as cloning, sequencing, or genetic testing.

PCR works by repeatedly cycling through a series of temperature changes that allow for the denaturation of DNA strands, annealing of primers that flank the target sequence, and extension of the new DNA strand by a DNA polymerase enzyme. Each cycle effectively doubles the amount of target DNA, leading to exponential amplification.

In contrast, DNA sequencing is used for determining the precise order of nucleotides in a segment of DNA, gel electrophoresis is a technique for separating DNA, RNA, or proteins based on size and charge, and Western blotting is specifically designed for detecting proteins in a sample. Therefore, the identification of PCR as the method for amplifying DNA underscores its critical role in molecular biology and genetic research.