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Question #46147
The Question
True metamerism in Annelids involves the internal partitioning of the coelom by intersegmental septa. If an experimental chemical selectively dissolves these septa in an earthworm without damaging the blood vessels or body wall, which of the following would be the most immediate physiological consequence?
Options
- A.
Blood will mix with the coelomic fluid, anatomically converting the closed circulatory system into an open type.
- B.
Equalization of coelomic hydrostatic pressure will occur, severely impairing peristaltic locomotion and the hemodynamic efficiency of the closed circulatory system.
- C.
Cutaneous respiration will cease entirely because the unpartitioned coelomic fluid can no longer transport dissolved oxygen to the deep tissues.
- D.
Excretion will halt completely as septal nephridia require intact septa to directly filter nitrogenous wastes from the closed blood vessels.
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
Metameres|Closed_System|Septa_Disruption
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often view metamerism merely as an external morphological feature rather than a critical internal physiological framework.
The trap lies in confusing the anatomical closure of the circulatory system (blood confined to vessels) with its functional dependence on the compartmentalized hydrostatic skeleton (septa) for maintaining pressure gradients.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Animal Kingdom - Class 11 |
| Concept | Annelida Circulatory System |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |