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Question #45228
The Question
A researcher is studying a novel molecule, 'Inhibitor-A', which acts as a competitive analogue of Acetyl-CoA. It specifically binds to the active site of Histone Acetyltransferase (HAT) enzymes in a eukaryotic cell culture. Based on the NCERT principles of DNA packaging and gene expression, what will be the primary molecular consequence of this inhibition?
Options
- A.
Lysine and arginine residues on histones lose their positive charge, promoting the formation of transcriptionally active euchromatin.
- B.
The basic amino acid residues of the histone octamer retain their positive charge, maintaining strong electrostatic binding with DNA and repressing transcription.
- C.
The negatively charged DNA dissociates from the nucleosome core due to charge repulsion, exposing promoter regions to RNA polymerase.
- D.
It directly inhibits the translation process by preventing the acetylation of the ribosomal subunits, halting polypeptide elongation.
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
Competitive Enzyme Inhibition Kinetics|Genetic Code Degeneracy|Histone Octamer Charge Interaction
Why This Question Is Tricky
Common Mistakes
The Conceptual Pivot lies in bridging the biochemical nature of histones (NCERT: positively charged basic amino acids Lysine/Arginine) with epigenetic regulation.
Students often memorize 'acetylation = active transcription' but fail to understand the electrostatic mechanism.
The trap is Option A, which describes the normal function of the enzyme rather than the consequence of its competitive inhibition.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Biomolecules - Class 11 |
| Concept | Competitive Enzyme Inhibition Kinetics |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |