The first restriction endonuclease to be discovered was :

Options

A. hlnd II
B. EcoR I
C. Baan HI
D. Pst I

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the name of the first restriction endonuclease that was discovered.

2. **Identifying the Key Information**: The video transcript mentions that the first restriction endonuclease discovered is "Hind II." It is important to note that this enzyme was isolated from a specific bacterium.

3. **Source of the Enzyme**: The transcript states that Hind II was isolated from the bacterium "Haemophilus influenzae." This is crucial information as it links the enzyme to its source.

4. **Function of Restriction Endonucleases**: The transcript explains that restriction endonucleases cut DNA at specific sequences. Hind II cuts at a particular site within a specific sequence of six base pairs.

5. **Importance of Restriction Endonucleases**: These enzymes are essential for DNA manipulation, as they cut DNA into discrete fragments, which can then be used in various biotechnological applications.

6. **Conclusion**: Based on the information provided, the first restriction endonuclease to be discovered is Hind II, isolated from Haemophilus influenzae.

**Final Answer**: The first restriction endonuclease to be discovered was Hind II.

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