Select the statement that is not correct for mRNA.

Options

A. Monocistronic mRNA encodes only one protein
B. A non-interrupted gene is also called a split gene
C. The mature mRNA consists exclusively of exons and has all introns removed
D. Eukaryotic RNA formed after transcription is known as precursor messenger RNA

Answer

To solve the question of which statement is not correct for mRNA, we will analyze each statement provided in the options.

### Step-by-Step Solution:

1. **Understanding mRNA**:
- mRNA, or messenger RNA, is a type of RNA that conveys genetic information from DNA to the ribosome, where proteins are synthesized.

2. **Analyzing the Statements**:
- **Statement 1**: "Monocistronic mRNA includes only one protein coding sequence."
- This statement is **correct**. Monocistronic mRNA is typical in eukaryotes and contains the coding sequence for a single protein.

- **Statement 2**: "A non-interrupted gene is called the split gene."
- This statement is **incorrect**. A non-interrupted gene is not referred to as a split gene; rather, split genes contain introns and exons, where introns are non-coding regions that are removed during mRNA processing.

- **Statement 3**: "The mature mRNA consists exclusively of exons and has all introns removed."
- This statement is **correct**. Mature mRNA is formed after splicing, where introns are removed, leaving only exons, which are the coding sequences.

- **Statement 4**: "Eukaryotic RNA formed after transcription is known as the precursor messenger RNA."
- This statement is **correct**. The RNA initially transcribed in eukaryotes is called precursor mRNA (pre-mRNA), which undergoes processing to become mature mRNA.

3. **Conclusion**:
- The statement that is not correct for mRNA is **Statement 2**: "A non-interrupted gene is called the split gene."

### Final Answer:
The incorrect statement regarding mRNA is **Statement 2**.

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