Answer:
In order to fit into the nucleus of the cell
Step-by-step explanation:
Nucleosome is the building blocks of Chromatins. Nucleosomes are formed when long chains of DNA molecules are wrapped around a set of eight proteins called HISTONES OCTAMER. The DNA coils around the core of the protein to form a nucleosome structure, which in turn undergoes further coiling to form the CHROMATIN.
The nucleus of the cell is way too small to accommodate the lenghty nature of the genetic material (DNA). Hence, in order to fit into the nucleus of a cell, the DNA needs to be packaged into an initial Nucleosome structure.