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Question #45943
The Question
Growth in plants is generally quantified by parameters such as an increase in dry weight. However, during the developmental transition to senescence, a mature leaf exhibits a 'net negative growth rate'—a continuous decline in dry weight prior to abscission. Which of the following statements regarding this physiological phase is INCORRECT?
Options
- A.
It is characterized by a hormonal shift where the senescence-promoting effects of Abscisic Acid (ABA) override the senescence-delaying effects of Cytokinins.
- B.
The decline in dry weight is primarily driven by the breakdown of cellular macromolecules and the remobilization of nutrients to younger sink organs.
- C.
It represents a systemic metabolic reversal where catabolic pathways dominate over anabolic pathways, leading to biological mass loss.
- D.
The synthesis of Auxins in these older mature leaves acts to prevent their abscission, directly antagonizing the effects of growth inhibitors.
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
Senescence vs Abscission|ABA|Growth Rate
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: The dual, age-dependent role of Auxins in abscission.
Common Misconception: Students rigidly categorize Auxins as absolute 'growth promoters' that always prevent abscission and antagonize inhibitors like ABA.
They frequently miss the specific NCERT nuance that Auxins prevent early drop but actually promote the abscission of older, mature plant organs.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Plant Growth and Development - Class 11 |
| Concept | Growth Rate Quantification |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |