In this animation we'll see the remarkable way our DNA is tightly packed up so that six feet of this long molecule fits into the microscopic nucleus of every cell. The process starts when DNA is wrapped around special protein molecules called histones. The combined loop of DNA and protein is called a nucleosome. The nucleosomes are packaged into a thread known as chromatin this fiber is then looped and further packaged using other proteins which are not shown here. The end result is that the DNA is tightly packed into the familiar structures we can see through a microscope, chromosomes. Chromosomes are not always present. They form around the times cells divide when the two copies of the cell's DNA need to be separated. At other times, as we can see now after the cell has divided, our DNA is less highly organized. It is still wrapped up around the histomes but not coiled into chromosomes.