In EcoRI, R is stand for

Options

A. strain RY 13
B. Stain Rd
C. Species RY 13
D. Species Rd

Answer

To solve the question regarding what the "R" in EcoRI stands for, we can break it down step by step:

### Step-by-Step Solution:

1. **Understanding EcoRI**:
- EcoRI is a type of restriction endonuclease, which are enzymes that cut DNA at specific sequences.

2. **Origin of the Name**:
- The name EcoRI is derived from the bacterium from which it was isolated. The components of the name are:
- "Eco" refers to the genus of the bacterium, which is *Escherichia*.
- "R" refers to a specific strain of that bacterium.

3. **Identifying the Strain**:
- The strain from which EcoRI was isolated is known as RY13. Therefore, the "R" in EcoRI stands for the strain RY13.

4. **Analyzing the Options**:
- The options provided in the question are:
- A) strain RY13
- B) strain RD
- C) species RY13
- D) species RD
- Since we established that "R" refers to the strain RY13, the correct answer is option A.

5. **Conclusion**:
- The "R" in EcoRI stands for strain RY13.

### Final Answer:
- The correct answer is **strain RY13**.