Assertion :- The split-gene arrangement complicates the definition of a gene in terms of a DNA segment.
In eukaryotes the monocistronic structural genes have interrupted coding sequence.

Options

A. If both Assertion & Reason are True & the Reason is a correct explanation of the Assertion.
B. If both Assertion & Reason are trur but Reason is not a correct explanation of the Assertion.
C. If Assertion is True but the Reason is Flase.
D. If both Assertion & Reason are false.

Answer

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that the split-gene arrangement complicates the definition of a gene in terms of a DNA segment.
- A split-gene arrangement refers to the presence of both coding (exons) and non-coding (introns) sequences within a gene.

2. **Defining Split Genes**:
- Split genes consist of exons, which are sequences that code for proteins, and introns, which are non-coding sequences that are removed during RNA processing.
- In eukaryotes, genes are often interrupted by introns, making the definition of a gene more complex than just a simple DNA segment.

3. **Understanding the Reason**:
- The reason provided states that in eukaryotes, monocistronic structural genes have interrupted coding sequences.
- Monocistronic means that a single mRNA molecule codes for only one protein, which is typical for eukaryotic genes.

4. **Analyzing the Relationship**:
- The assertion is correct because the presence of introns does complicate the definition of a gene, as the gene is not a continuous sequence of coding DNA.
- The reason is also correct because monocistronic genes in eukaryotes do have interrupted coding sequences due to the presence of introns.

5. **Evaluating the Explanation**:
- While both the assertion and reason are true, the reason does not fully explain why the split-gene arrangement complicates the definition of a gene. The reason focuses on the characteristics of monocistronic genes rather than directly addressing the complications introduced by split genes.

6. **Conclusion**:
- Both the assertion and the reason are true, but the reason is not a correct explanation of the assertion.

### Final Answer:
Both assertion and reason are true, but the reason is not a correct explanation of the assertion.

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