4. Genes & Chromosomes
Compaction of DNA
Supercoiling
Relaxed

9. Genes & Chromosomes
Size of genome vs. size of cell

11. Genes & Chromosomes
Compaction of DNA

13. Genes & Chromosomes
Compaction of DNA
30 nm fiber

14. Genes & Chromosomes Compaction of DNA Beads-on-a-string
Protein (histones, basic) + DNA (acidic) = Nucleosome

15. Genes & Chromosomes
Compaction of DNA
Beads-on-a-string

19. Genes & Chromosomes Compaction of DNA
Topoisomerases can underwind and/or relax DNA Important for DNA packaging, DNA replication