NEETZoologyBiotechnology - Principles and Processes
Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): In the Polymerase Chain Reaction (PCR), Taq polymerase catalyzes the extension of primers and survives the high-temperature denaturation step. Reason (R): Taq polymerase, isolated from the bacterium Thermus aquaticus, is responsible for breaking the hydrogen bonds between the two strands of DNA at
Options
- AAssertion (A) is true but Reason (R) is false.
- BBoth Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).
- CBoth Assertion (A) and Reason (R) are true but Reason (R) is not the correct explanation of Assertion (A).
- DAssertion (A) is false but Reason (R) is true.
Correct answer
A. Assertion (A) is true but Reason (R) is false.
Step-by-step solution
Assertion (A) is true because Taq polymerase is a thermostable DNA polymerase that remains active during the high-temperature denaturation step of PCR and catalyzes the extension of primers. Reason (R) is false because the breaking of hydrogen bonds between the two strands of DNA (denaturation) is caused by the application of high heat itself, not by the enzymatic action of Taq polymerase. Taq polymerase only synthesizes the new DNA strand during the extension step and does not act as a helicase to unwind or denatu