Packing six feet of DNA into every cell

Human DNA strands are approximately 6 feet in length (7). To store them compactly within cells they are tightly wound around proteins called histones.Read more: /wiki/Histone
(photo from http://en.wikipedia.org/wiki/Histone)


A single DNA strand is wrapped around multiple histones, in a beads-on-a-string structure. These are then compacted, forming the 30nm fiber, then further compressed onto scaffold proteins to form chromosomes.
Read more: /wiki/Nucleosome
(photo from http://en.wikipedia.org/wiki/File:Chromatin_Structures.png)