Before You Begin
Question #45139
The Question
Adenosine deaminase (ADA) is crucial for the proliferation of lymphocytes. Its deficiency leads to Severe Combined Immunodeficiency (SCID), a scenario that conceptually mirrors ecological 'Co-extinction', where the loss of an enzymatic 'habitat' leads to the cellular 'extinction' of lymphocytes. Which of the following statements regarding ADA deficiency and its biological parallels is NOT correct?
Options
- A.
The accumulation of toxic purine metabolites inhibits DNA replication, triggering apoptosis in both T and B lymphocytes.
- B.
Similar to how the extinction of a host fish leads to the co-extinction of its obligate parasites, the deletion of the ADA gene leads to the loss of cell-mediated and humoral immunity.
- C.
Introduction of a functional ADA cDNA into the patient's lymphocytes using a retroviral vector provides a permanent cure, analogous to successfully reintroducing a keystone species.
- D.
Enzyme replacement therapy and bone marrow transplantation are available treatments for this condition, but neither is completely curative.
Check Your Answer
Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Evolutionary_Exception
Tackle problems where standard rules evolve or change based on specific environmental constraints.
Concepts Behind This Question
ADA_Deficiency|Lymphocytes|Host-Parasite_Dependencies
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: The distinction between temporary and permanent cures in Gene Therapy.
Students often misinterpret the successful insertion of ADA cDNA into lymphocytes as a 'permanent cure'.
The trap leverages the positive-sounding ecological analogy ('successfully reintroducing a keystone species') to mask the biological reality that somatic lymphocytes have a finite lifespan, requiring periodic infusions.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Biotechnology and Its Applications - Class 12 |
| Concept | ADA Deficiency Genetic Correction |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |