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Question #45114
The Question
A researcher attempts to generate a transgenic animal cell line by introducing a recombinant DNA construct using microinjection. The host cell has a pre-existing mutation that compromises its tumor-suppressor regulatory regions. Rapid oncogenic transformation is observed shortly after the procedure. Which of the following best explains the molecular basis of this rapid transformation specific to the chosen gene transfer method?
Options
- A.
The technique utilizes disarmed retroviruses that inadvertently cause insertional mutagenesis near the host's proto-oncogenes.
- B.
Direct delivery of the construct into the nucleus bypasses cytoplasmic nucleases, allowing the introduced sequence to immediately exploit the compromised G1/S checkpoint.
- C.
The physical piercing of the plasma membrane by the micro-pipette directly phosphorylates and activates cellular proto-oncogenes.
- D.
The method coats the recombinant DNA with cationic lipids, which fuse with the nuclear envelope and disrupt cell cycle regulation.
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
Microinjection Specificity|Oncogenes vs Proto-oncogenes|Animal Cells
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often fail to distinguish between 'vector-mediated' (e.g., retroviruses) and 'vectorless/direct' (e.g., microinjection) methods of gene transfer in animal cells.
This question tests the NCERT fact that microinjection delivers DNA directly to the nucleus, and synthesizes it with the concept of cell cycle regulation, requiring the student to recognize that bypassing the cytoplasm prevents nuclease degradation and allows immediate interaction with compromised nuclear checkpoints.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Biotechnology : Principles and Processes - Class 12 |
| Concept | Microinjection Specificity |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |