The part of a gene which codes for an enzyme is called

Options

A. Cistron.
B. Codon .
C. exon.
D. intron .

Answer

To solve the question "The part of a gene which codes for an enzyme is called", we can analyze the options provided and understand the terminology related to genetics.

### Step-by-Step Solution:

1. **Understanding the Question**:
- We need to identify the specific part of a gene that is responsible for coding enzymes. Enzymes are proteins, and genes code for proteins.

2. **Identifying Key Terms**:
- The options given are: Sistrone, Chordone, Axone, and Introne. We need to determine which of these terms correctly relates to the coding of enzymes.

3. **Analyzing Each Option**:
- **Sistrone**: This term is not commonly used in genetics. However, it seems to be a misinterpretation or misspelling of "cistron," which refers to a segment of DNA that codes for a specific polypeptide chain (protein).
- **Chordone**: This term does not relate to any known genetic terminology and is likely incorrect.
- **Axone**: This term is not relevant in the context of genetics; it typically refers to the long part of a neuron.
- **Introne**: This term appears to be a misspelling of "intron," which refers to non-coding sequences within a gene that are removed during RNA processing.

4. **Correct Answer**:
- The correct term that refers to the part of a gene coding for an enzyme (which is a type of protein) is **Cistron**. A cistron is a segment of DNA that encodes a single polypeptide chain.

### Final Answer:
The part of a gene which codes for an enzyme is called **Cistron**.

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