During PCR amplification, Taq DNA polymerase adds nucleotides to the growing DNA strand. A significant limitation of standard Taq polymerase compared to human DNA polymerase is the lack of which enzymatic activity?

• A 3' to 5' exonuclease activity ✓
• B 5' to 3' polymerase activity
• C 5' to 3' exonuclease activity
• D Helicase activity

Explanation

Standard Taq DNA polymerase lacks 3' to 5' exonuclease proofreading activity, leading to higher error rates during PCR compared to high-fidelity polymerases. It possesses 5' to 3' polymerase activity for elongation and 5' to 3' exonuclease activity for primer removal.

Reference: Lehninger Principles of Biochemistry, 7th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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