Second letter of the name of restriction endonuclease came from the

Options

A. Genus of organism
B. Species of organism
C. Family of organism
D. Class of organism

Answer

To solve the question regarding the second letter of the name of restriction endonuclease, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Function of Restriction Endonucleases**:
- Restriction endonucleases are enzymes that cut DNA at specific sequences. They are crucial tools in biotechnology for DNA manipulation.

2. **Identify the Naming Convention**:
- The names of restriction endonucleases typically follow a specific format. For example, EcoRI is a well-known restriction enzyme.

3. **Break Down the Example**:
- In the name EcoRI:
- "Eco" refers to the genus name of the organism from which the enzyme is derived, which is *Escherichia*.
- "R" refers to the specific strain of the organism.
- "I" is a Roman numeral indicating the order of discovery.

4. **Focus on the Second Letter**:
- In the example of EcoRI, the second letter is "C".
- This "C" comes from the species name, which in this case is *coli* (from *Escherichia coli*).

5. **Conclusion**:
- Therefore, the second letter of the name of restriction endonuclease comes from the species of the organism.

### Final Answer:
The second letter of the name of restriction endonuclease comes from the **species of organism**.

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