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Question #47619
The Question
A genetic mutation in a Zea mays (maize) plant causes its bundle sheath cell walls to become thin and highly permeable to gaseous exchange. If this mutant plant is grown under high light intensity and high temperature, which of the following physiological consequences will be most directly observed?
Options
- A.
Increased oxygenase activity of RuBisCO in bundle sheath cells, leading to phosphoglycolate formation and reduced net productivity.
- B.
PEP carboxylase in the mesophyll cells will competitively bind with oxygen, initiating the photorespiratory pathway.
- C.
The primary carboxylation event will shift entirely to the bundle sheath cells, utilizing RuBP as the initial CO2 acceptor.
- D.
The plant will maintain its high photosynthetic yield because the continuous decarboxylation of malic acid will outcompete oxygen influx.
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
Rubisco|PEP_Carboxylase|Bundle_Sheath_Cells
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Understanding the structural-functional dependency of Kranz anatomy.
Students often memorize that C4 plants do not undergo photorespiration, but fail to realize this is purely due to the physical gas-impermeable barrier of the bundle sheath cells.
The trap in Option B exploits the common misconception that PEPcase can bind oxygen like RuBisCO.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Photosynthesis in Higher Plants - Class 11 |
| Concept | Kranz Anatomy Adaptations |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |