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Question #46545
The Question
Given below are two statements regarding the application of Polymerase Chain Reaction (PCR) in molecular diagnostics:
Statement I: Standard PCR using Taq polymerase is highly recommended for amplifying DNA when absolute sequence fidelity is required, such as detecting single nucleotide mutations in proto-oncogenes. Statement II: Taq polymerase lacks 3' to 5' exonuclease activity, making it prone to introducing artificial base substitutions during in vitro amplification.
In the light of the above statements, choose the most appropriate answer from the options given below:
Options
- A.
Both Statement I and Statement II are correct
- B.
Both Statement I and Statement II are incorrect
- C.
Statement I is correct but Statement II is incorrect
- D.
Statement I is incorrect but Statement II is correct
Check Your Answer
Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Regulatory_Failure
Understand how NOT, EXCEPT, and logical constraints are used to manipulate exam results.
Concepts Behind This Question
Oncogenes vs Proto-oncogenes|Taq Polymerase Thermal Stability|Competent Cell Preparation
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often conflate the widespread use of Taq polymerase in standard PCR with absolute replication fidelity.
The trap lies in recognizing that while Taq is thermostable (a massive advantage), it lacks 3' to 5' exonuclease proofreading activity (a critical disadvantage for diagnostic cloning).
Failing to distinguish between these properties leads to misunderstanding why false positives occur in oncogene amplification.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Human Health and Disease - Class 12 |
| Concept | Oncogenes vs Proto-oncogenes |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |