Why and how bacteria can be made 'competent' ?

Explanation

**Step-by-Step Text Solution:**

1. **Understanding Competence in Bacteria:**
- Competence refers to the ability of bacteria to take up foreign DNA from their environment. This is essential for genetic engineering, where recombinant DNA needs to be introduced into bacterial cells.

2. **Nature of DNA:**
- DNA is a hydrophilic molecule, meaning it does not easily cross the hydrophobic lipid bilayer of bacterial cell membranes. Therefore, special methods are required to facilitate the uptake of DNA.

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