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Question #47534
The Question
In certain angiosperms like Citrus, nucellar polyembryony results in multiple embryos developing simultaneously within the confines of a single megasporangium without systemic failure. If a similar phenomenon of multiple simultaneous zygotic outgrowths occurs in a simple thalloid alga, it typically leads to the collapse of thallus organization due to severe nutrient competition. Which primary evolutionary adaptation in angiosperms prevents this localized system failure during polyembryony?
Options
- A.
The symmetrical meiotic division of the megaspore mother cell, ensuring equal resource distribution among all developing embryos.
- B.
The presence of a highly differentiated suspensor and a dedicated triploid endosperm to manage spatial and nutritional constraints.
- C.
The ability of the nucellar parenchyma to undergo independent photosynthesis to support the high metabolic demand of multiple embryos.
- D.
The formation of multiple independent archegonia within the megasporangium to compartmentalize each developing embryo.
Check Your Answer
Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Evolutionary_Exception
Tackle problems where standard rules evolve or change based on specific environmental constraints.
Concepts Behind This Question
Chlorophyceae|Stephanokont_Flagellation|Cellular_Polarity
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often memorize 'polyembryony in Citrus' without understanding the metabolic and spatial constraints required to support multiple embryos.
The question tests the evolutionary distinction between Thallophytes (which lack specialized embryonic support) and Angiosperms (which utilize the endosperm and suspensor).
It also employs a classic 'Taxonomic Trap' in Option D by introducing 'archegonia', a structure absent in angiosperms, and a 'Process Trap' in Option A by falsely claiming megasporogenesis is symmetrical.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Plant Kingdom - Class 11 |
| Concept | Algal Thallus Organization |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |