Theoretical Calculation of Number of Nucleosomes in a Mammalian Cell

The number of nucleosomes in a mammalian cell can be calculated theoretically based on certain assumptions and estimations. Let's discuss the process step by step.

Assumptions:

- A nucleosome contains 146 base pairs of DNA wrapped around an octamer of histone proteins.
- The diameter of a nucleosome is approximately 10 nanometers.
- The average diameter of a mammalian cell is about 20 micrometers.
- The DNA content of a mammalian cell is about 6 picograms.

Calculations:

1. Calculation of the length of DNA in a mammalian cell

- Since the DNA content of a mammalian cell is about 6 picograms, we can assume that the total length of DNA in a cell is about 2 meters (based on the fact that one base pair weighs approximately 1 picogram).
- Therefore, the total number of base pairs in a mammalian cell is about 6 billion.

2. Calculation of the number of nucleosomes in a mammalian cell

- Since each nucleosome contains 146 base pairs of DNA, the total number of nucleosomes in a cell can be calculated by dividing the total number of base pairs by 146.
- Therefore, the number of nucleosomes in a mammalian cell is approximately 41 million.

3. Calculation of the volume occupied by nucleosomes in a mammalian cell

- Since the diameter of a nucleosome is approximately 10 nanometers, the volume occupied by a single nucleosome can be calculated using the formula for the volume of a sphere.
- Therefore, the volume occupied by a single nucleosome is approximately 5.2 x 10^-21 cubic meters.
- Since the number of nucleosomes in a mammalian cell is approximately 41 million, the total volume occupied by nucleosomes in a cell can be calculated by multiplying the volume of a single nucleosome by the number of nucleosomes.
- Therefore, the total volume occupied by nucleosomes in a mammalian cell is approximately 2.1 x 10^-11 cubic meters.

Conclusion:

Based on the above calculations, we can theoretically estimate that there are approximately 41 million nucleosomes present in a mammalian cell. However, it is important to note that this is just an estimation and the actual number of nucleosomes may vary depending on various factors such as the cell type, stage of the cell cycle, and environmental conditions.

it's not possible to answer how many nucleosomes in mammalian cells as it will vary,but in human it should be approx 30million