Why must an engineered DNA polymerase be used in PCR and not the one that occurs naturally?
A)It needs to work at very cold temperatures.
B)It needs to attach to DNA without a primer.
C)It must work in the 3' to 5' direction,adding nucleotides to the 5' end.
D)It must work on single-stranded DNA at high temperatures and attach to a primer.
E)It must attach without a primer,work in the 3' to 5' direction and function at very cold temperatures.

Question

Quizplus · Accepted Answer

An engineered DNA polymerase must be used in PCR because it needs to work on single-stranded DNA at high temperatures and attach to a primer. Naturally occurring DNA polymerases cannot withstand the high temperatures required in PCR and do not attach to primers without modifications. Additionally, the engineered polymerase must work in the 5' to 3' direction, which is the same direction as naturally occurring polymerases.

Why Must an Engineered DNA Polymerase Be Used in PCR