A scientist uses the polymerase chain reaction (PCR) to amplify a specific segment of DNA. Which of the following best explains why a heat-stable DNA polymerase (such as Taq polymerase) is essential for this process?

Core Concept

PCR involves repeated cycles of heating to 95°C to separate the DNA strands. Heat-stable polymerases like Taq do not denature at these high temperatures, eliminating the need to add fresh enzyme after every cycle.