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Question #46519
The Question
Secretory IgA (sIgA) plays a critical role in mucosal immunity within the gastrointestinal tract. Suppose a researcher observes that while plasma cells in the Mucosa-Associated Lymphoid Tissue (MALT) are successfully producing dimeric IgA, these antibodies are being rapidly degraded by proteolytic enzymes upon entering the intestinal lumen. Which of the following structural modifications is most likely failing to occur prior to the antibody's release into the lumen?
Options
- A.
Addition of the J-chain by the mucosal epithelial cells to stabilize the heavy chains.
- B.
Attachment of the secretory component by the mucosal epithelial cells to prevent enzymatic cleavage.
- C.
Glycosylation of the variable region by plasma cells to mask protease cleavage sites.
- D.
Formation of disulfide bridges between two IgA monomers by the enterocytes.
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
MALT_Structure|Secretory_Component|J-Chain
Why This Question Is Tricky
Common Mistakes
Location and Functional Trap: Students often conflate the J-chain (which dimerizes IgA and is made by plasma cells) with the Secretory Component (which protects IgA from proteases and is added by mucosal epithelial cells).
The question pivots on identifying both the correct protective structure and its precise cellular origin.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Human Health and Disease - Class 12 |
| Concept | Antibody Structure Logic |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |