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Question #47574
The Question
Evolutionarily, earthworms (Annelida) exhibit a closed circulatory system, whereas insects (Arthropoda), despite having a more complex organ-system organization and higher metabolic rates (e.g., for flight), possess an open circulatory system. Which of the following best explains how insects overcome the metabolic constraints of an open circulatory system to meet their high oxygen demands?
Options
- A.
Their hemolymph contains high concentrations of hemocyanin, which transports oxygen more rapidly than the dissolved hemoglobin in earthworms.
- B.
A highly branched tracheal system delivers atmospheric oxygen directly to the cellular level, effectively decoupling gaseous exchange from circulation.
- C.
The insect heart pumps hemolymph at a significantly higher pressure than the annelid heart, ensuring rapid perfusion of the hemocoel.
- D.
Insects possess specialized book lungs that directly oxygenate the hemolymph before it enters the open tissue spaces.
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
Economic Importance Matrix|Bioactive Molecule Origin|Rhodophyceae
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often fall for the teleological fallacy that 'higher' taxonomic organization (Arthropoda over Annelida) necessitates a 'more advanced' (closed) circulatory system.
When confronted with the reality of an open system in highly active insects, students mistakenly assume the hemolymph must have superior respiratory pigments (Option A) or high pressure (Option C).
The core NCERT insight tested here is the complete functional decoupling of respiration and circulation via the tracheal system, which solves the metabolic constraint.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Plant Kingdom - Class 11 |
| Concept | Economic Importance Matrix |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |