Assume that instead of taq polymerase, another polymerase, one that is very heat-sensitive, was used in a pcr. what differences would one observe when this new experiment is compared to the original experiment (one that includes taq polymerase)?

Taq polymerase is a thermostable which states that it can even work at higher temperature. The main function of using this enzyme is that it is used to amplify the DNA which will help in producing ample amount of DNA sample.

The enzyme activity is temperature dependent. The denaturation and annealing steps of the PCR occurs at very high temperature.

Any other enzyme used at such an high temperature would have decreased the enzyme activity and the procedure would not be completed.