The length of DNA in each one of our cells is roughly 2 mete

The length of DNA in each one of our cells is roughly 2 meters. Compared to the nucleus of your cells is about 10 microns in diameter. How can DNA fit in your nucleus? Give quantitative argument.

Solution

DNA double helix wound 1.65 times around a core of eight histone proteins (called nucleosome) at regular intervals along the entire length of the chromosome. These nucleosome beads are about 10 nm in diameter which is about 7 times shorter than the 2-nm diameter double helix without the histones.

Nucleosomes fold up to form a 30-nanometer chromatin fiber, which are about 50 times shorter than the extended form.