Write the methods to introduce alien DNA into host cells?

Explanation

To introduce alien DNA into host cells, several methods can be employed. Here is a step-by-step breakdown of these methods:

### Step-by-Step Solution:

1. **Using Vectors:**
- **Definition:** Vectors are DNA molecules used to deliver foreign genetic material into a host cell.
- **Types of Vectors:**
- **Plasmids:** These are extra-chromosomal, circular, self-replicating DNA molecules commonly used in genetic engineering.
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