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Question #45332
The Question
During dicot embryogeny, the transition from a radially symmetrical structure to a bilaterally symmetrical structure is critically dependent on the apical-basal gradient of a specific phytohormone. If a chemical inhibitor of polar auxin transport is applied to a developing Capsella embryo exactly at the globular stage, which of the following developmental anomalies will most likely occur?
Options
- A.
The embryo will arrest at the globular stage, failing to transition into a heart-shaped embryo due to the lack of root-shoot axis differentiation.
- B.
The basal cell will fail to divide transversely, preventing the formation of the 6-10 celled suspensor.
- C.
The embryo will prematurely develop into a mature torpedo shape, but will exhibit fused cotyledons.
- D.
The hypophysis will immediately differentiate into the shoot apical meristem instead of the root cap.
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
Auxin|Cytokinin|Suspensor
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often memorize the morphological sequence of embryogeny (Proembryo -> Globular -> Heart -> Mature) from NCERT Class 12 without integrating it with the physiological triggers (Auxin gradients) from NCERT Class 11.
The trap lies in assuming embryonic stages are purely time-dependent cell divisions rather than being strictly regulated by spatial hormonal gradients that dictate symmetry breaking.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Sexual Reproduction in Flowering Plants - Class 12 |
| Concept | Embryogeny Directionality |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |