Before You Begin
Question #47690
The Question
Statins, bioactive molecules derived from the yeast Monascus purpureus, are widely prescribed to manage lipid metabolism dysfunction. Physiologically, their administration disrupts endogenous lipid synthesis, forcing the body to maintain cellular cholesterol homeostasis through alternative pathways. Which of the following statements INCORRECTLY describes the mechanism and homeostatic consequence of this pharmacological intervention?
Options
- A.
Statins closely resemble the substrate of the cholesterol-synthesizing enzyme, competing directly for its active site.
- B.
The drug acts as a non-competitive inhibitor by binding to an allosteric site, thereby reducing the Vmax of cholesterol synthesis.
- C.
The drug-induced intracellular cholesterol deficit triggers a homeostatic upregulation of LDL receptors on hepatocyte membranes.
- D.
Increased density of LDL receptors accelerates the sequestration of cholesterol from blood plasma, effectively lowering circulating lipid levels.
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
Biocontrol_Agents_Synergy|Statin|Metabolite_Production
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Integrating enzyme kinetics (Biomolecules) with human welfare (Microbes) and cellular homeostasis.
Students often memorize that 'statins lower cholesterol' but fail to connect the exact enzymatic mechanism (competitive inhibition at the active site) with the downstream physiological adaptation (LDL receptor upregulation).
The trap lies in misidentifying the type of enzyme inhibition (Non-competitive vs.
Competitive) and its kinetic consequences (Vmax vs.
Km).
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Microbes in Human Welfare - Class 12 |
| Concept | Statin Mechanism of Action |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |