What does the term "denaturation" refer to in the context of PCR?

Denaturation refers specifically to the process in polymerase chain reaction (PCR) where the double-stranded DNA is separated into two single strands. This is typically achieved by applying heat, which disrupts the hydrogen bonds between the complementary bases of the DNA, allowing the strands to unwind and become accessible for the next steps of the PCR process.

This step is crucial because it creates the single-stranded templates that are necessary for the following stages of PCR, where primers will attach and the new strands of DNA will be synthesized. Without denaturation, the DNA would remain in its double-stranded form, preventing the primers from effectively binding and the polymerase enzyme from synthesizing new DNA strands.