Before You Begin
Question #46271
The Question
A researcher treats a developing angiosperm seed with a highly specific drug that disrupts microtubule dynamic instability immediately after double fertilization. While the primary endosperm nucleus (PEN) continues its initial development, the zygote fails to differentiate into a suspensor and embryonal mass, instead forming a multinucleated syncytium. Which of the following statements regarding the cellular basis of this developmental arrest is INCORRECT?
Options
- A.
The disruption of microtubules prevents the formation of the phragmoplast, halting the centrifugal expansion of the cell plate.
- B.
The failure of Golgi-derived vesicles to align at the equator prevents the formation of the middle lamella precursor.
- C.
The endomembrane system fails to package and deposit cellulose microfibrils required for the formation of the initial cell plate.
- D.
The drug uncouples karyokinesis from cytokinesis in the zygote, mimicking the natural early developmental stage of the primary endosperm nucleus.
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
Seed Embryology|Microtubule Dynamic Instability|Endomembrane System Connectivity
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot & Composition Trap: Students frequently conflate 'cell wall formation' with 'cellulose deposition'.
While mature plant cell walls are rich in cellulose, the NCERT explicitly states that the initial cell plate represents the middle lamella (composed of pectates).
The trap exploits the assumption that the endomembrane system (Golgi) directly deposits cellulose during cytokinesis, testing both biochemical composition and cellular location specificity.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Morphology of Flowering Plants - Class 11 |
| Concept | Seed Embryology |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |