The conventional method for naming the restriction enzymes is followed. In case of EcoRI, the R indicates

Options

A. genus
B. species
C. strain
D. name of the scientist

Answer

To answer the question regarding the naming convention of the restriction enzyme EcoRI, we can break it down into the following steps:

### Step-by-Step Solution:

1. **Understanding the Naming Convention**:
- Restriction enzymes are named based on a systematic convention that includes information about their source organism and specific characteristics.

2. **Identifying the Components of the Name**:
- The name "EcoRI" can be dissected into parts:
- "Eco" refers to the genus and species of the organism from which the enzyme is derived.
- "R" is the third letter in the name and indicates a specific characteristic of the strain.
- "I" is a Roman numeral that indicates the order of discovery of the enzyme.

3. **Determining the Source Organism**:
- In this case, "Eco" comes from *Escherichia coli*, which is the bacterium from which the enzyme is isolated.

4. **Understanding the Significance of "R"**:
- The letter "R" specifically indicates the type of strain of *Escherichia coli*. In this context, "R" stands for the "rough" strain of the bacterium.

5. **Conclusion**:
- Therefore, in the case of EcoRI, the "R" indicates the "rough strain" of *Escherichia coli* from which the restriction enzyme was isolated.

### Final Answer:
In EcoRI, the "R" stands for the "rough strain" of *Escherichia coli*.

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