What is the function of polymerase chain reaction (PCR)?

The function of polymerase chain reaction (PCR) is to amplify specific DNA sequences, creating millions of copies for analysis. This technique is essential in molecular biology because it allows for the selective amplification of a targeted DNA segment, making it possible to study small samples of DNA in greater detail. PCR utilizes cycles of denaturation, annealing, and extension, enabling researchers to exponentially replicate the DNA of interest.

By producing a large quantity of a specific DNA fragment, PCR facilitates various downstream applications such as genetic analysis, cloning, and diagnostic testing. This amplification process is crucial when the available DNA is limited, allowing scientists to obtain sufficient material for further experimentation and analysis. In contrast, options such as sequencing entire genomes or inserting genes into plasmids pertain to different molecular techniques and do not reflect the primary purpose of PCR. Similarly, while extracting RNA from cells is another important laboratory procedure, it is not relevant to the function of PCR.