Final answer:
Taq polymerase is used in PCR due to its ability to handle high temperatures, its lower error rate, and faster rate of DNA synthesis.
Step-by-step explanation:
Taq polymerase is used in PCR as opposed to DNA polymerase from another source such as E. coli because Taq polymerase has several advantages. Firstly, Taq polymerase is able to withstand the high temperatures used in PCR, making it suitable for the repeated heating and cooling cycles involved in the reaction. Secondly, Taq polymerase is less likely to make errors during DNA synthesis compared to other polymerases. Lastly, Taq polymerase is able to work at a faster rate, allowing for more efficient DNA amplification.