Packing of DNA is required are DNA molecules in eukaryotes is very large. DNA therefore packs itself up into structures referred to as chromosomes. This allows DNA to be stored within the nucleus of cells. The process is simple, with DNA being the lowest for of storage, moving to nucleosomes, which is protein interacting with DNA to condense it, then to a solenoid, which is an organized form of nucleosomes. The final structure is the chromosome.