DNA exists in the condensed, chromatin form to fit into the nucleus.DNA loops twice around a histone octamer to form a nucleosome. A nucleosome consists of 2x (H2A, H2B, H3, H4)

H1 binds to the nucleosome and to "linker DNA," thereby stabilizing the chromatin fiber.

Phosphate groups give DNA a Θ charge. Lysine and arginine give histones a ⊕ charge.

In mitosis, DNA condenses to form chromosomes. DNA and histone synthesis occurs during the S phase.

Mitochondria have their own DNA, which is circular and does not utilize histones.