Questions: Why is the Taq-polymerase special compared to most other polymerases? a) It can resist low temperatures b) It can resist high temperatures c) It synthesizes DNA d) It unfolds DNA

The answer is (b): It can resist high temperatures.

Explanation for each option: a) It can resist low temperatures - This is incorrect. Taq-polymerase is not particularly known for its resistance to low temperatures. Its unique property is its ability to function at high temperatures.

b) It can resist high temperatures - This is correct. Taq-polymerase is derived from the thermophilic bacterium Thermus aquaticus, which thrives in hot environments such as hot springs. This enzyme is stable and active at high temperatures, which is why it is used in the polymerase chain reaction (PCR) process, where repeated heating cycles are required.

c) It synthesizes DNA - While this is true, it is not what makes Taq-polymerase special compared to most other polymerases. Many polymerases synthesize DNA, but Taq-polymerase's ability to withstand high temperatures is what sets it apart.

d) It unfolds DNA - This is incorrect. Taq-polymerase does not unfold DNA. The process of DNA denaturation (unfolding) during PCR is achieved by heating the DNA, not by the action of the polymerase.

Summary: Taq-polymerase is special because it can resist high temperatures, making it ideal for use in PCR, where the enzyme must remain active through multiple cycles of heating and cooling.