Which is not correct matched

Options

A. Agrobacterium `rArr` Ti -plasmid
B. Cosmid `rArr` Vector DNA
C. Rhizobium `rArr` Asymbiotic `N_(2)` fixer
D. Albinism `rArr` Autosomal recessive gene

Answer

To determine which option is not correctly matched, we will analyze each option provided in the question.

### Step-by-Step Solution:

1. **Agrobacterium**:
- Agrobacterium is a genus of bacteria known for its role in plant pathology. It is particularly known for causing tumors in dicot plants through the transfer of DNA (specifically the Ti plasmid) into the plant cells.
- **Conclusion**: This statement is correct.

2. **Cosmid Vector**:
- A cosmid is a type of vector used in genetic engineering. It is a hybrid of a plasmid and a lambda phage, allowing it to carry larger DNA fragments than a standard plasmid.
- **Conclusion**: This statement is correct.

3. **Rhizobium**:
- Rhizobium is a genus of bacteria that forms symbiotic relationships with legumes, fixing nitrogen in the root nodules of these plants. The statement claims it is an "endosymbiotic N2 fixer," which is misleading because while it does fix nitrogen, it is not an endosymbiont in the traditional sense; it exists in a symbiotic relationship outside the plant cells.
- **Conclusion**: This statement is incorrect.

4. **Albinism**:
- Albinism is indeed an autosomal recessive genetic disorder characterized by a lack of melanin pigment in the skin, hair, and eyes.
- **Conclusion**: This statement is correct.

### Final Conclusion:
The option that is not correctly matched is **Rhizobium**, as it is inaccurately described in the context of being an "endosymbiotic N2 fixer."

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