3. The Structure of Chromosomes

Chromatin Consists of DNA, Proteins, and RNA

Histones Are Small, Basic Proteins

Nucleosomes Are the Fundamental Organizational Units of Chromatin

Nucleosomes Are Packed into Highly Condensed Chromosome Structures

BOX 24-1 Epigenetics, Nucleosome Structure, and Histone Variants

BOX 24-2 Curing Disease by Inhibiting Topoisomerases

BOX 24-3 X Chromosome Inactivation by an lncRNA: Preventing Too Much of a Good (or Bad) Thing

Condensed Chromosome Structures Are Maintained by SMC Proteins

Bacterial DNA Is Also Highly Organized