Before You Begin
Question #46539
The Question
Read the following statements regarding the production and diagnostic quantification of human α-lactalbumin in transgenic cows (e.g., Rosie):
I. The transgene must be integrated with a mammary gland-specific promoter to ensure the foreign protein is secreted exclusively in milk. II. A drastic drop in ELISA-quantified protein levels in subsequent generations, despite an intact transgene, is often due to DNA hypermethylation of the regulatory sequence. III. ELISA quantification relies on antigen-antibody interactions to directly measure the exact copy number of the transgene in the bovine genome. IV. Epigenetic silencing of the transgene alters the primary amino acid sequence of the protein, thereby preventing the ELISA capture antibodies from binding.
Choose the correct option:
Options
- A.
Statements I and II are correct
- B.
Statements II and III are correct
- C.
Statements I, III, and IV are correct
- D.
Statements I and IV are correct
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
ELISA|Transgenic Animal|Recombinant DNA
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Distinguishing between quantitative diagnostic tools (ELISA for proteins) and genomic tools (PCR for DNA), alongside understanding the mechanism of epigenetic silencing.
Students often confuse epigenetic suppression (which lowers protein yield) with genetic mutation (which alters protein structure), and mistakenly assume ELISA can quantify gene copy numbers rather than expressed protein levels.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Human Health and Disease - Class 12 |
| Concept | ELISA Logic |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |