In EcoRI the letter R is derived from the name of

Options

A. Genus
B. Species
C. Both genus and species
D. Strain

Answer

To answer the question "In EcoRI, the letter R is derived from the name of," we can break it down step by step:

### Step-by-Step Solution:

1. **Understanding EcoRI**:
- EcoRI is a restriction enzyme, which is used in molecular biology for cutting DNA at specific sequences.

2. **Components of EcoRI**:
- The name EcoRI can be broken down into four parts:
- **E**: This stands for the genus *Escherichia*.
- **co**: This represents the species *coli*.
- **R**: This letter refers to a specific strain of the bacterium.
- **I**: This is a Roman numeral indicating that it is the first enzyme isolated from that strain.

3. **Identifying the Strain**:
- The strain referred to by the letter R in EcoRI is *RY13*. This is a specific strain of *Escherichia coli* from which the enzyme was first isolated.

4. **Conclusion**:
- Since the letter R in EcoRI specifically denotes a strain (RY13), the answer to the question is that the letter R is derived from the name of a strain.

### Final Answer:
The letter R in EcoRI is derived from the name of a **strain**.

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