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Question #46352
The Question
Alpha-1 antitrypsin (A1AT) is a biological product clinically used to treat emphysema. In a patient with a severe genetic deficiency of A1AT, blood analysis reveals an abnormally high reticulocyte count alongside chronic respiratory distress. Which of the following best explains this compensatory hematological observation?
Options
- A.
Systemic protease-antiprotease imbalance damages erythrocyte membranes, leading to premature hemolysis and subsequent erythropoietin-mediated compensatory erythropoiesis.
- B.
Decreased alveolar surface area causes chronic hypercapnia, which directly stimulates the myeloid stem cells in the red bone marrow to release immature erythrocytes.
- C.
Accumulation of defective A1AT proteins in hepatocytes shifts the primary site of erythropoiesis from the red bone marrow to the liver to meet oxygen demands.
- D.
The absence of A1AT increases the binding affinity of hemoglobin for oxygen, forcing the bone marrow to overproduce erythrocytes to facilitate oxygen dissociation at tissues.
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
Bone_Marrow|Protease_Inhibition|Respiratory_Surface
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students typically compartmentalize A1AT strictly within Biotechnology (transgenic animals) and Respiratory System (emphysema).
This question requires synthesizing those facts with Body Fluids and Circulation (erythrocyte turnover) and Excretory/Endocrine Systems (erythropoietin mechanism).
The trap lies in assuming respiratory distress directly stimulates the bone marrow via CO2 (Option B), rather than recognizing the systemic proteolytic damage to RBC membranes and the indirect renal EPO pathway.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Body Fluids and Circulation - Class 11 |
| Concept | Erythrocyte Lifecycle and Location |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |