DNA and genomes

The phosphate groups have pKas of around 2 and around 7. This means DNA is negatively charged in the cell. The phosphate groups and the OH of the deoxyribose make the DNA exterior hydrophilic. The bases are almost water insoluble but with the possibility of hydrogen bonds.

DNA structure

chromatin

Figure 4.11

Figure 4.12

Figure 4.13

Figure 4.20

Size and organization of genomes  Different organisms have different amounts of haploid DNA and the correlation with complexity of the organism is poor. Organization of the human genome Repetitive DNA makes up over 50% of the human DNA and the protein coding regions only about 2%.