Question:
Assertion (A): Repetitive sequences make up a very large portion of human genome.
Reason (R): Repetitive sequences do not have direct coding functions in the genome.
Assertion (A): Repetitive sequences make up a very large portion of human genome.
Reason (R): Repetitive sequences do not have direct coding functions in the genome.
Reason (R): Repetitive sequences do not have direct coding functions in the genome.
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While repetitive DNA does not code for proteins, it is highly useful in DNA fingerprinting because these non-coding regions show high levels of polymorphism between individuals!
Updated On: Aug 16, 2026
- Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of the Assertion (A).
- Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of the Assertion (A).
- Assertion (A) is true, but Reason (R) is false.
- Assertion (A) is false, but Reason (R) is true.
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The Correct Option is B
Solution and Explanation
Concept:
Insights from the Human Genome Project (HGP) revealed key structural features of human DNA:
• Less than 2% of the genome codes for proteins.
• Repetitive sequences (highly repeated DNA stretches) form a massive portion of the human genome.
• These repetitive sequences do not code directly for proteins, but they offer critical insights into chromosome structure, dynamics, and evolutionary history.
Step 1: Check the Assertion validity.
Data from the Human Genome Project confirms that repetitive sequences make up a very large fraction of human genomic DNA. Thus, Assertion (A) is true.
Step 2: Check the Reason validity.
Repetitive sequences are non-coding segments of DNA, meaning they lack direct translation functions for producing protein products. Thus, Reason (R) is true.
Step 3: Analyze the causal link.
The lack of a direct coding function does not explain why these sequences are present in such high numbers across the genome. The accumulation of repetitive elements is due to evolutionary duplication events, transposition, and genetic drift over deep time. Therefore, Reason (R) is not the correct explanation for Assertion (A). This corresponds to Option (B).
• Less than 2% of the genome codes for proteins.
• Repetitive sequences (highly repeated DNA stretches) form a massive portion of the human genome.
• These repetitive sequences do not code directly for proteins, but they offer critical insights into chromosome structure, dynamics, and evolutionary history.
Step 1: Check the Assertion validity.
Data from the Human Genome Project confirms that repetitive sequences make up a very large fraction of human genomic DNA. Thus, Assertion (A) is true.
Step 2: Check the Reason validity.
Repetitive sequences are non-coding segments of DNA, meaning they lack direct translation functions for producing protein products. Thus, Reason (R) is true.
Step 3: Analyze the causal link.
The lack of a direct coding function does not explain why these sequences are present in such high numbers across the genome. The accumulation of repetitive elements is due to evolutionary duplication events, transposition, and genetic drift over deep time. Therefore, Reason (R) is not the correct explanation for Assertion (A). This corresponds to Option (B).
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