Why is Taq polymerase used in the polymerase chain reaction (PCR)?
Answer and explanation
Correct answer: B. It stays active at the high temperature that separates the DNA strands in each cycle
- Step 1: Each PCR cycle heats the DNA to about 95 degrees Celsius to separate the strands.
- Step 2: Taq polymerase comes from a heat-loving bacterium, so it is not denatured and can extend the primers in every cycle.
Answer
it stays active at high temperatures.
Why not the others: Cutting at sequences is done by restriction enzymes; joining is by ligase; PCR separates strands by heat, not at room temperature.
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