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Question #46872
The Question
A comparative physiological study observes systemic tissue hypoxia in both a human and an earthworm (Pheretima) following severe ionic imbalance and metabolic stress. Which of the following statements correctly identifies the physiological compensatory mechanism for increasing oxygen-carrying capacity in these organisms?
Options
- A.
The human kidney's juxtaglomerular cells release erythropoietin to stimulate erythropoiesis, whereas the earthworm increases hemoglobin production from blood glands in the 4th, 5th, and 6th segments, which dissolves directly into the blood plasma.
- B.
Both organisms utilize a renal or nephridial feedback loop where hypoxia induces the secretion of erythropoietin, but the earthworm packages its hemoglobin into nucleated erythrocytes.
- C.
The human utilizes erythropoietin from the macula densa cells, while the earthworm relies on its pharyngeal nephridia to synthesize respiratory pigments for the coelomic fluid.
- D.
The human increases RBC count via renal erythropoietin, whereas the earthworm compensates by increasing the synthesis of hemocyanin dissolved in its hemolymph.
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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
Earthworm Nephridial Placement|Erythropoietin Function|Calcium Homeostasis
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often assume all organisms with hemoglobin package it into erythrocytes and use similar endocrine feedback loops (like EPO).
This question forces a cross-phyla synthesis, testing the exact anatomical origin of hemoglobin in earthworms (blood glands in segments 4, 5, 6) versus the endocrine trigger in humans (JG cells of the kidney), highlighting the evolutionary divergence in hypoxia compensation.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Structural Organisation in Animals - Class 11 |
| Concept | Earthworm Nephridial Placement |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |