Which one of the following is not correctly matched ?

Options

A. Transcription - synthesis of DNA from RNA.
B. Translation - Using information in mRNA to synthesis protein .
C. Repressor protein - Binds to operator to stop transcription of structural gene.
D. Operson - Structural genes, operator, promoter and inhibitor.

Answer

To solve the question "Which one of the following is not correctly matched?", we will analyze each option provided in the question step by step.

### Step 1: Analyze the first option
- **Term**: Transcription
- **Matched with**: Synthesis of DNA from RNA
- **Analysis**: This is incorrect. Transcription is the process where RNA is synthesized from a DNA template, not the other way around. Therefore, this option is not correctly matched.

### Step 2: Analyze the second option
- **Term**: Translation
- **Matched with**: Using information in mRNA to synthesize protein
- **Analysis**: This is correct. Translation is the process where ribosomes use the information in mRNA to synthesize proteins. Therefore, this option is correctly matched.

### Step 3: Analyze the third option
- **Term**: Repressor protein
- **Matched with**: Binds to the operator to stop transcription of the structural gene
- **Analysis**: This is correct. Repressor proteins bind to the operator region of DNA and inhibit the transcription of genes. Therefore, this option is correctly matched.

### Step 4: Analyze the fourth option
- **Term**: Operon
- **Matched with**: Structural gene, operator, promoter, and inhibitor
- **Analysis**: This is correct. An operon is a functional unit of DNA that includes a set of genes (structural genes), an operator, a promoter, and sometimes an inhibitor. Therefore, this option is correctly matched.

### Conclusion
After analyzing all the options, we find that the first option is the only one that is not correctly matched. The correct answer to the question is the first option.

### Final Answer:
The option that is not correctly matched is: **Transcription - Synthesis of DNA from RNA**.

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