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Question #46356
The Question
During a severe case of Erythroblastosis fetalis, the fetus suffers from massive erythrocyte destruction due to maternal Rh antibodies. To compensate for the resulting chronic hypoxia, a homeostatic feedback loop is triggered. Which of the following accurately describes this compensatory mechanism and its direct physiological consequence?
Options
- A.
Fetal hypoxia stimulates increased erythropoietin release, driving extramedullary hematopoiesis which results in hepatosplenomegaly and the release of nucleated erythroblasts into circulation.
- B.
The fetal kidney secretes renin in response to hypoxia, which directly stimulates the bone marrow to rapidly release mature, enucleated erythrocytes.
- C.
Maternal erythropoietin crosses the placenta to supplement fetal erythropoiesis, causing the fetal spleen to sequester destroyed RBCs and enlarge.
- D.
Fetal hypoxia triggers the liver to convert excess hemoglobin into bilirubin, which acts as a hormone to stimulate rapid bone marrow proliferation.
Check Your Answer
Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Comparative_Analysis
Sharpen your ability to evaluate multiple scenarios and distinguish between competing potential answers.
Concepts Behind This Question
ABO-Rh Incompatibility Logic|Erythropoietin Function|Hypoxia
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often memorize 'Erythroblastosis fetalis = Rh incompatibility' without understanding the physiological origin of the term 'erythroblastosis' (the presence of immature, nucleated erythroblasts in the blood).
The question tests the ability to link a circulatory crisis (hemolysis) to an endocrine feedback loop (Hypoxia -> EPO) and its anatomical consequence (Extramedullary hematopoiesis).
The distractors utilize 'Functional Confusion' (Renin vs EPO, Bilirubin as a hormone) and 'Location Traps' (Maternal vs Fetal EPO).
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Body Fluids and Circulation - Class 11 |
| Concept | ABO-Rh Incompatibility Logic |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |