Choose the mismatched pair from given options.

Options

A. Insertional inactivation - beta-galactosidase
B. YAC vector - Yeast artificial chromosome
C. BAC vector - Largest bacteriophage vector
D. Ti plasmid - Agrobacterium tumefaciens

Answer

To solve the question of identifying the mismatched pair from the given options, we will analyze each option step by step.

### Step-by-Step Solution:

1. **Understanding Insertional Inactivation**:
- Insertional inactivation refers to a method where a desired gene (transgene) is inserted into a specific site of a gene, which in this case is the beta-galactosidase gene.
- When the transgene is inserted, it disrupts the function of beta-galactosidase, leading to its inactivation.
- **Conclusion**: The pairing of insertional inactivation with beta-galactosidase is correct.

**Hint**: Remember that insertional inactivation involves inserting a gene that disrupts the function of another gene.

2. **Analyzing YAC Vector**:
- YAC (Yeast Artificial Chromosome) is a vector used to clone large fragments of DNA, particularly eukaryotic DNA.
- It is indeed used for carrying large DNA sequences.
- **Conclusion**: The pairing of YAC vector with its definition is correct.

**Hint**: YAC vectors are specifically designed for cloning large eukaryotic DNA segments.

3. **Examining BAC Vector**:
- BAC (Bacterial Artificial Chromosome) is also a vector used for cloning large DNA fragments, similar to YAC.
- It is specifically used for bacterial DNA.
- **Conclusion**: The pairing of BAC vector with its definition is correct.

**Hint**: Like YAC, BAC is used for cloning large DNA, but it is derived from bacterial systems.

4. **Reviewing Ti Plasmid**:
- Ti plasmid is derived from Agrobacterium tumefaciens, a pathogenic bacterium used in genetic engineering to transfer genes into plants.
- This pairing is accurate as Ti plasmids are indeed associated with Agrobacterium.
- **Conclusion**: The pairing of Ti plasmid with Agrobacterium tumefaciens is correct.

**Hint**: Ti plasmids are crucial for plant genetic engineering and are sourced from a specific bacterium.

5. **Identifying the Mismatched Pair**:
- After reviewing all options, we find that:
- Insertional inactivation with beta-galactosidase: Correct
- YAC vector: Correct
- BAC vector: Correct (but it was incorrectly paired with "largest bacteriophage vector" in the original question)
- Ti plasmid with Agrobacterium: Correct
- The only mismatched pair is the BAC vector, which should not be paired with bacteriophage but rather with its correct definition.

**Final Conclusion**: The mismatched pair is option C (BAC vector).

### Final Answer:
The correct answer for the question is option C.

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