Which structure involved in genetic engineering

Options

A. Plastid
B. Plasmid
C. Codon
D. None

Answer

### Step-by-Step Solution:

1. **Understanding Genetic Engineering**: Genetic engineering involves the manipulation of an organism's DNA to introduce new traits or characteristics. This process often requires specific tools and structures.

2. **Identifying Key Structures**: In genetic engineering, several structures can be involved, but we need to focus on the most relevant ones. The question provides options: Plastid, Plasmid, Codone, or None.

3. **Analyzing the Options**:
- **Plastid**: This is a type of organelle found in plant cells that is involved in photosynthesis and storage. It is not directly involved in genetic engineering.
- **Plasmid**: This is a small, circular piece of DNA that is separate from chromosomal DNA and can replicate independently. Plasmids are commonly used as vectors to introduce foreign genes into host cells during genetic engineering.
- **Codone**: This appears to be a misspelling of "codon," which refers to a sequence of three nucleotides in DNA or RNA that codes for a specific amino acid. While codons are important in the context of protein synthesis, they are not structures used in genetic engineering.
- **None**: This option suggests that none of the given structures are involved in genetic engineering, which is incorrect since plasmids are indeed involved.

4. **Conclusion**: Based on the analysis, the correct answer is **Plasmid** (Option B), as it serves as a vector in the process of genetic engineering.

### Final Answer:
The structure involved in genetic engineering is **Plasmid**.

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