The number of nucleotides present in the restriction sequence of the first restriction endonuclease is

Options

A. 6
B. 8
C. 12
D. 16

Answer

To determine the number of nucleotides present in the restriction sequence of the first restriction endonuclease, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Restriction Endonuclease**: The first restriction endonuclease we are discussing is HindIII.

2. **Understand the Sequence**: The restriction sequence recognized by HindIII consists of a specific arrangement of nucleotides. The sequence is typically represented as a series of bases.

3. **Determine the Length of the Sequence**: The restriction site for HindIII is a sequence of 6 nucleotides. This means that the sequence recognized by HindIII is composed of 6 specific bases.

4. **Complementary Strand**: In addition to the original strand, there is a complementary strand that also contains 6 nucleotides.

5. **Calculate Total Nucleotides**: Since both the original and complementary strands contain 6 nucleotides each, we can calculate the total number of nucleotides:
- Original strand: 6 nucleotides
- Complementary strand: 6 nucleotides
- Total = 6 + 6 = 12 nucleotides.

6. **Final Answer**: Therefore, the total number of nucleotides present in the restriction sequence of the first restriction endonuclease (HindIII) is 12.