Which one is a true statement regarding DNA polymerase used in PCR?
- It is used to ligate introduced DNA in recipient cell
- It remains active at high temperature
- It serves as a selectable marker
- It is isolated from a virus
Answer
(2) It remains active at high temperature
Solution
As per NCERT, the DNA polymerase used in PCR is Taq polymerase, isolated from the bacterium Thermus aquaticus.
It is thermostable, it remains active at the high temperature used to denature the double-stranded DNA in each cycle.
(Ligation is done by DNA ligase; it is not a selectable marker; it comes from a bacterium, not a virus.)
Answer: (2)