Before You Begin
Question #46240
The Question
Consider a xerophytic plant with leaves modified into spines to minimize transpirational loss, growing alongside a typical mesophyte. If the global atmospheric concentration artificially doubles (e.g., > 800 ), which of the following statements correctly describes the physiological shift in their competitive advantage?
Options
- A.
The plant will exhibit a higher rate of carbon assimilation than the plant due to its inherently lower compensation point.
- B.
The plant will gain a competitive advantage as elevated minimizes photorespiration, whereas the plant is already saturated.
- C.
The xerophytic plant will increase its stomatal aperture to utilize the excess , negating the water-conservation benefit of its leaf modifications.
- D.
The plant will outcompete the plant because PEP carboxylase maintains a higher affinity for than RuBisCO under elevated conditions.
Check Your Answer
Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Comparative_Analysis
Sharpen your ability to evaluate multiple scenarios and distinguish between competing potential answers.
Concepts Behind This Question
Leaf Modifications|C4 Pathway Efficiency|Compensation Point Logic
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often blindly memorize that 'C4 plants are more efficient than C3 plants' without understanding the environmental context.
The trap relies on confusing the evolutionary advantage of a low CO2 compensation point (which helps in hot, dry, low-CO2 conditions) with performance under high-CO2 conditions.
The core NCERT fact tested is that C3 plants are not yet CO2 saturated at current atmospheric levels, whereas C4 plants are.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Morphology of Flowering Plants - Class 11 |
| Concept | Leaf Modifications |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |