When a foreign DNA is introduced into an organism, how is it maintained in the host and how is it transferred to the progeny of the organism?

Explanation

### Step-by-Step Solution:

1. **Introduction of Foreign DNA**: To introduce foreign DNA into a host organism, a vector is used. A common example of a vector is the plasmid PBR 322, which is often utilized in genetic engineering.

2. **Insertion into Vector**: The foreign DNA is inserted into the vector. This combination of the vector and foreign DNA is crucial for the next steps.

3. **Transformation into Host**: The vector containing the foreign DNA is then introduced into the host organism. This process is known as transformation.

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