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Question #45868
The Question
In a modified Hershey-Chase experiment, T2 bacteriophages labeled with 32P and 35S are introduced to a thermally adapted strain of E. coli at a high temperature that completely denatures the viral tail fibers prior to contact. If the standard experimental steps of infection, blending, and centrifugation are subsequently performed, which of the following correctly describes the expected distribution of radioactivity?
Options
- A.
Both 32P and 35S will be recovered entirely in the supernatant.
- B.
32P will be found in the bacterial pellet, while 35S remains in the supernatant.
- C.
35S will be found in the bacterial pellet, while 32P remains in the supernatant.
- D.
Neither 32P nor 35S will be detectable in the supernatant due to viral degradation.
Check Your Answer
Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Evolutionary_Exception
Tackle problems where standard rules evolve or change based on specific environmental constraints.
Concepts Behind This Question
Bacteriophage|Host_Specificity|Darwinian_Fitness
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often rote-memorize the classic Hershey-Chase conclusion (32P in pellet, 35S in supernatant) without analyzing the mechanical prerequisites of the assay.
This question tests the understanding of the 'Infection' phase.
By introducing a physiological failure (denatured tail fibers preventing adsorption), it forces the student to deduce the physical location of the isotopes (intracellular vs. extracellular) when the injection mechanism fails.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Molecular Basis of Inheritance - Class 12 |
| Concept | Hershey-Chase Isotopic Labeling |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |