A good vector must have

Options

A. ability to replicate anutonomously
B. Single sites for a large number of restriction enzymes
C. easy transformation to the host cells
D. high molecular weight for enhanced stability

Answer

### Step-by-Step Solution:

1. **Definition of a Vector**: A vector is a small DNA molecule that carries foreign DNA into a host cell. It is essential for cloning and gene transfer.

2. **Characteristics of a Good Vector**:
- **Ability to Replicate Autonomously**: A good vector must be able to replicate independently within the host cell. This ensures that the foreign DNA is copied along with the vector during cell division.

- **Single Site for Large Number of Restriction Enzymes**: The vector should have a single site that can be recognized by multiple restriction enzymes. This allows for flexibility in inserting foreign DNA, as different enzymes can be used depending on the specific needs of the experiment.

- **Easy Transformation to Most Cells**: A good vector should facilitate easy transformation into various host cells. This is crucial for ensuring that the foreign DNA can be successfully introduced into the target cells.

- **Low Molecular Weight**: Contrary to the idea of high molecular weight, a good vector should ideally have a low molecular weight. This enhances stability and makes it easier for the vector to enter host cells.

3. **Conclusion**: A good vector must have the ability to replicate autonomously, a single site for multiple restriction enzymes, easy transformation capabilities, and a low molecular weight for enhanced stability.