Before You Begin
Question #47528
The Question
A angiosperm is subjected to prolonged high temperatures and high light intensity immediately following successful syngamy and triple fusion. Despite successful fertilization, the plant exhibits a high rate of seed abortion and stunted endosperm development. Which of the following best explains the primary metabolic reason for this phenomenon?
Options
- A.
High temperature induces stomatal closure, causing an internal spike that competitively inhibits the carboxylase activity of RuBisCO.
- B.
RuBisCO functions primarily as an oxygenase, initiating a wasteful pathway that consumes ATP and releases fixed carbon, thereby starving the developing sink.
- C.
The plant temporarily shifts to a pathway to avoid water loss, which consumes extra ATP and leaves insufficient energy for endosperm maturation.
- D.
Increased photorespiration generates reactive oxygen species that directly degrade the Primary Endosperm Nucleus (PEN) before it can divide.
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
Angiosperm Double Fertilization|Equational Division Logic|DNA vs Chromosome Content
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Integrating Plant Physiology (Photosynthesis) with Plant Reproduction.
Students often fail to connect the metabolic drain of photorespiration (loss of fixed carbon and ATP) to its macroscopic consequence: the inability to support energetically expensive post-fertilization events (source-sink starvation).
The trap in Option A tests the exact gas concentration changes during stomatal closure, a common point of confusion.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Plant Kingdom - Class 11 |
| Concept | Angiosperm Double Fertilization |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |