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Question #45991
The Question
A researcher sows seeds of a 'winter variety' of wheat in the spring season. To ensure immediate germination, the seeds are treated with a high concentration of Gibberellic Acid (GA), completely bypassing their natural winter cold exposure. Based on the principles of plant growth and development, which of the following best describes the subsequent physiological fate of these plants?
Options
- A.
The seeds will fail to germinate because the antagonistic effect of Abscisic Acid (ABA) on seed dormancy can only be degraded by prolonged low-temperature exposure.
- B.
The plants will germinate and exhibit normal vegetative growth but will fail to flower within the growing season, as the lack of low-temperature exposure prevents the generation of the flowering stimulus.
- C.
The plants will germinate and flower normally, because exogenous GA acts as a universal substitute for the vernalization requirement in all winter annuals.
- D.
The plants will germinate and flower precociously, as high GA concentrations directly trigger the synthesis of florigen in the shoot apical meristem regardless of temperature.
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
Vernalization Mechanism|Seed Dormancy Breaking
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students frequently conflate the two distinct roles of cold exposure in plants (breaking seed dormancy via stratification vs. inducing reproductive competence via vernalization).
The trap relies on the overgeneralization of the NCERT fact that 'GA promotes bolting in rosette plants', leading students to falsely assume GA universally substitutes for vernalization in all plants, including winter wheat.
This tests the ability to decouple vegetative germination from reproductive switching.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Plant Growth and Development - Class 11 |
| Concept | Vernalization Mechanism |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |