Find out the number of nucleosomes present in a human cell.

Options

A. 16.50 million
B. 16.50 billion
C. 33 million
D. 200 million

Explanation

To find the number of nucleosomes present in a human cell, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Structure of Nucleosomes**:
- A nucleosome is a structural unit of eukaryotic chromosomes, consisting of a segment of DNA wrapped around a core of histone proteins. Each nucleosome typically contains about 200 base pairs of DNA.

2. **Determine the Total Number of Base Pairs in a Human Cell**:
- A typical human cell contains approximately \(6.6 \times 10^9\) base pairs of DNA.

3. **Calculate the Number of Nucleosomes**:
- Since each nucleosome is formed by 200 base pairs, we can calculate the total number of nucleosomes by dividing the total number of base pairs by the number of base pairs per nucleosome.
- The formula to calculate the number of nucleosomes is:
\[ \text{Number of Nucleosomes} = \frac{\text{Total Base Pairs}}{\text{Base Pairs per Nucleosome}} = \frac{6.6 \times 10^9 \text{ base pairs}}{200 \text{ base pairs/nucleosome}} \]

4. **Perform the Calculation**:
- Performing the division:
\[ \text{Number of Nucleosomes} = \frac{6.6 \times 10^9}{200} = 3.3 \times 10^7 \]

5. **Conclusion**:
- Therefore, the number of nucleosomes present in a human cell is \(3.3 \times 10^7\) nucleosomes.

### Final Answer:
The number of nucleosomes present in a human cell is \(3.3 \times 10^7\).

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