A functional unit of gene which speciefic 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. **Understand the Question**: The question asks for the term that describes a functional unit of a gene responsible for the synthesis of a single polypeptide.

2. **Identify Key Terms**: The key terms in the question are "functional unit of gene" and "synthesis of one polypeptide".

3. **Recall Genetic Terminology**: In genetics, there are specific terms that refer to different units and functions. We need to recall the definitions of terms related to genes and their functions.

4. **Consider the Options**: The options provided in the video transcript include:
- Cystron
- Rekon
- Clone
- Codon

5. **Analyze Each Option**:
- **Cystron**: This is defined as a segment of DNA or RNA that codes for a specific polypeptide. This matches the requirement of the question.
- **Rekon**: This refers to a unit of recombination, not directly related to polypeptide synthesis.
- **Clone**: This refers to genetically identical copies of an organism, not a unit of gene.
- **Codon**: This is a sequence of three nucleotides that corresponds to a specific amino acid, but it does not refer to the entire unit that synthesizes a polypeptide.

6. **Select the Correct Answer**: Based on the analysis, the term that best fits the description of a functional unit of a gene that specifies the synthesis of one polypeptide is **Cystron**.

### Final Answer:
The functional unit of a gene which specifies the synthesis of one polypeptide is known as **Cystron**.

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