Section 3: Genetics, Cellular and Molecular Biology
Recombinant DNA technology
Subtopic: Fundamentals of Recombinant DNA technology
Question Statement:
Choose the appropriate pair of primers to amplify the following DNA fragment by the polymerase
chain reaction (PCR).
5' - GACCTGIGG-
3' -CTGGACACC-
--ATACGGGAT- 3'
- TATGCCCTA-5'
Primers
P. 5' -GACCTGTGG-3'
Q. 5'-CCACAGGTC-3'
R. 5' -TAGGGCATA-3'
S.
5' - ATCCCGTAT-3'
Options:
(A) P and R
(B) P and S
(C) Q and R
(D) Q and S
Official Answer Key:
B
Step-by-Step Solution & Explanation
### **Official Solution & Step-by-Step Derivation (GATE BT 2015 Q.32)**
**1. Governing Concept & Syllabus Classification**:
- **Section**: BT
- **Question Type**: **MCQ** (1 Mark)
- **Core Topic**: Biochemistry, Microbiology & Molecular Biology
**2. Detailed Step-by-Step Analytical & Scientific Derivation**:
- **Systematic Conceptual & Option-by-Option Evaluation**:
- Problem Focus: *"--- PAGE 10 ---
Choose the appropriate pair of primers to amplify the following DNA fragment by the polymerase
chain reaction (PCR).
5' - GACCTGIGG-
3' -CTGGACACC-
--ATACGGGAT- 3'
- TATGCCCTA-5'
Primers
P. 5' -GACCTGTGG-..."*
- **Option (B) [CORRECT]**: *"P and S"*
- Validated by canonical biochemistry/biotechnology literature. Specifically matches the molecular mechanism, kinetic model, or empirical finding required.
- **Option (A) [INCORRECT]**: *"P and R"* does not satisfy the precise boundary conditions or molecular specificity.
- **Option (C) [INCORRECT]**: *"Q and R"* does not satisfy the precise boundary conditions or molecular specificity.
- **Option (D) [INCORRECT]**: *"Q and S
Options :
1.
A
2. V B
3. * C
4.
* D"* does not satisfy the precise boundary conditions or molecular specificity.
**3. Final Answer / Verification Summary**:
- **Official GATE Answer Key**: **B**
- **Scoring Criteria**: 1 Mark (Negative marking: -0.33 marks).
Practice This in Real CBT Exam Interface
Test yourself with the official TCS-iON palette, virtual calculator, and immediate performance analytics.