Number of nucleotides present in one linker DNA are

Options

A. 54
B. 108
C. 146
D. 200

Answer

### Step-by-Step Solution:

1. **Understanding Linker DNA**:
- Linker DNA is the segment of DNA that connects two nucleosomes in the chromatin structure. It is an important part of the overall organization of DNA in the cell nucleus.

2. **Nucleosome Structure**:
- A nucleosome consists of a core of histone proteins around which DNA is wrapped. Each nucleosome is made up of approximately 146 base pairs of DNA.

3. **Linker DNA in Chromatin**:
- In the Beads on a String model of chromatin, the nucleosomes appear like beads, and the linker DNA is the string connecting these beads.

4. **Determining the Number of Nucleotides in Linker DNA**:
- The number of nucleotides in linker DNA can vary depending on the species and cell type. However, on average, the linker DNA contains about 108 base pairs.

5. **Conversion of Base Pairs to Nucleotides**:
- Since each base pair consists of two nucleotides (one on each strand of the DNA), the number of nucleotides in the linker DNA can be calculated as:
\[ \text{Number of nucleotides} = \text{Number of base pairs} \times 2 \]
- Therefore, for 108 base pairs:
\[ \text{Number of nucleotides} = 108 \times 2 = 216 \]

### Final Answer:
The number of nucleotides present in one linker DNA is **216 nucleotides**.

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