Which of the following can prove useful as a vector in both a prokaryote and eukaryote?

Options

A. Shuttle vector
B. Cosmid
C. plasmid
D. Eco IM

Answer

To determine which of the options can serve as a vector in both prokaryotic and eukaryotic cells, we need to analyze each option provided.

### Step-by-Step Solution:

1. **Understanding Vectors**: Vectors are DNA molecules used to deliver genetic material into cells. They can be used in genetic engineering to introduce new genes into an organism.

2. **Identifying the Types of Cells**:
- **Prokaryotes**: These are single-celled organisms that lack a nucleus and membrane-bound organelles (e.g., bacteria).
- **Eukaryotes**: These are organisms whose cells have a nucleus and membrane-bound organelles (e.g., plants, animals, fungi).

3. **Evaluating Each Option**:
- **Shuttle Vector**: This is designed to replicate in both prokaryotic and eukaryotic cells. It can carry foreign DNA and is engineered to function in both types of cells, making it a versatile tool in genetic engineering.
- **Cosmid**: This is a hybrid between a plasmid and a phage, primarily used in prokaryotic systems. It is not typically used in eukaryotic systems.
- **Plasmid**: These are small circular DNA molecules found in prokaryotes. While some plasmids can be used in eukaryotic cells, they are not universally effective across both types.
- **EcoRI**: This is a restriction enzyme, not a vector. It is used to cut DNA at specific sites but does not serve as a vector itself.

4. **Conclusion**: Among the options, the **shuttle vector** is the only one that can function effectively as a vector in both prokaryotic and eukaryotic cells.

### Final Answer:
**Shuttle vector** is the correct answer as it can be used as a vector in both prokaryotes and eukaryotes.

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