Which feature of bacteria makes them especially useful in biotechnology ?

Options

A. They are often pathogens.
B. The have a unique genetic code .
C. They have cell walls.
D. They reproduce rapidly.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about a specific feature of bacteria that makes them particularly useful in biotechnology.

2. **Analyzing the Options**: We have four options to consider:
- Option 1: They are often pathogens.
- Option 2: They have a unique genetic code.
- Option 3: They have cell walls.
- Option 4: They reproduce rapidly.

3. **Evaluating Each Option**:
- **Option 1**: "They are often pathogens."
- While some bacteria are pathogenic, this characteristic does not contribute to their utility in biotechnology. Therefore, this option is incorrect.

- **Option 2**: "They have a unique genetic code."
- Bacteria do have a unique genetic code, but this alone does not explain their usefulness in biotechnology. Thus, this option is also incorrect.

- **Option 3**: "They have cell walls."
- The presence of cell walls, which are made of peptidoglycan, is a structural feature but does not directly relate to their application in biotechnology. Hence, this option is incorrect.

- **Option 4**: "They reproduce rapidly."
- This is a significant feature of bacteria. They can reproduce every 20 minutes, leading to rapid population growth. This characteristic allows for quick generation times in experiments and applications in genetic engineering and other biotechnological processes. Therefore, this option is correct.

4. **Conclusion**: The feature of bacteria that makes them especially useful in biotechnology is that they reproduce rapidly.

**Final Answer**: They reproduce rapidly.

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