Review Question - QID 109047

Polymerase chain reaction (PCR) is a diagnostic tool that is used to amplify a given sequence of DNA. It relies upon heat-resistant DNA polymerase in order to function during the elongation phase of the reaction.

PCR is a method to amplify sequences of DNA. Requirements for PCR include a DNA template that includes the target gene of interest to be amplified, a heat-resistant polymerase, nucleotides, and primers created from the flanking sequences of the gene to be amplified. The heat-resistant polymerase creates the copies of the nucleic acid based on primers that flank the DNA sequence during the elongation phase of PCR.

Incorrect Answers:
Answer 1: DNA primers are required for the annealing stage of PCR. During the annealing phase, the temperature is cooled and the primers anneal to the specific sequence on each strand.

Answer 2: The nucleotide sequence of the target region does not need to be known for PCR. Only the flanking sequences of the exon to be amplified need to be known so that complementary primers can be synthesized.

Answer 3: PCR involves DNA sequences that are amplified. The amino acid/peptide sequence that a gene codes for is not necessary.

Answer 4: The elongation phase is done at a higher temperature and thus the polymerase during this step must be heat-stable. A heat-sensitive polymerase would denature.

Bullet summary:
Polymerase chain reaction (PCR) is used to amplify a given sequence of DNA, and It relies upon a heat-resistant DNA polymerase.