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Question #47743
The Question
A biotechnologist is attempting to introduce a recombinant plasmid containing a nematode-specific gene into various host cells. Read the following statements regarding the gene delivery methods and identify the INCORRECT statement:
Options
- A.
Recombinant DNA can be forced into bacterial cells by incubating them with divalent calcium cations, followed by a brief heat shock at 42°C and returning them to ice.
- B.
Intact plant cells can be made competent for direct DNA uptake by alternating temperature treatments (ice to 42°C), as the thermal shock creates transient pores in the rigid cellulose matrix.
- C.
Biolistics is an ideal method for transforming plant cells, utilizing high-velocity micro-projectiles of gold or tungsten coated with DNA to mechanically bypass the cell wall barrier.
- D.
Disarmed retroviruses are utilized to deliver desirable genes into animal cells, whereas Agrobacterium tumefaciens is primarily used as a vector for dicotyledonous plants.
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
Bioreactor_Geometry|Downstream_Processing|Secondary_Metabolites
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often memorize the 'heat shock' method for making cells 'competent' without realizing it is anatomically restricted to prokaryotes.
The trap relies on the student failing to account for the mechanical rigidity of the plant cell wall, which cannot be bypassed by thermal/osmotic shock, necessitating entirely different physical methods (Biolistics) or biological vectors.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Biotechnology : Principles and Processes - Class 12 |
| Concept | Elution Process |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |