A functional unit of gene which specifies the synthesis of one polypeptide is known as :-

Options

A. recon
B. clone
C. codon
D. cistron

Answer

To solve the question "A functional unit of gene which specifies the synthesis of one polypeptide is known as:", we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks for the term that describes a functional unit of a gene responsible for the synthesis of one polypeptide.

2. **Identifying Key Terms**:
- Functional unit of a gene
- Synthesis of one polypeptide

3. **Analyzing the Options**:
- **Recon**: This term refers to the smallest recombinable unit within a cistron, but it does not specify the synthesis of a polypeptide.
- **Clone**: This refers to a cell or organism that is genetically identical to another, not specifically related to gene function.
- **Codon**: This is a sequence of three nucleotides in DNA or RNA that codes for a specific amino acid, but it is not a functional unit of a gene.
- **Cistron**: This term is used to describe a gene that specifies the synthesis of a single polypeptide. It is a functional unit of genetic information.

4. **Selecting the Correct Answer**: Based on the analysis, the correct answer is **Cistron**. A cistron is a segment of DNA that encodes for a single polypeptide chain.

5. **Conclusion**: Therefore, the functional unit of a gene that specifies the synthesis of one polypeptide is known as a **Cistron**.

### Final Answer:
Cistron

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