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Question #47546
The Question
A researcher treats the microspore mother cells of a Pinus plant with colchicine during meiosis. The resulting pollen grains are then used to pollinate a normal, untreated female cone of the same species. What will be the ploidy of the resulting zygote and the endosperm in the mature seed, respectively?
Options
- A.
3n and 3n
- B.
3n and n
- C.
4n and 2n
- D.
2n and n
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
Gymnosperm Endosperm|Angiosperm Endosperm|Double Fertilization|Ploidy Shift
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: The ontogeny of endosperm in Gymnosperms vs.
Angiosperms.
Students often reflexively link 'endosperm' to fertilization and the male gamete's ploidy (Angiosperm bias).
By altering the male gamete's ploidy via colchicine, the trap tests the student's conviction in the NCERT fact that gymnosperm endosperm is strictly a pre-fertilization, haploid female gametophytic tissue, completely independent of the male gamete.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Plant Kingdom - Class 11 |
| Concept | Gymnosperm Endosperm Identity |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |