Fig. 2 Phosphate group

Fig. 3 Purines

Fig. 4 Pyrimidines

Fig. 5 Single strand of DNA showing alternating sugar-phosphate backbone.

Fig. 6 Base pairing between two antiparallel strands of DNA.

Fig. 7 B-form of DNA (right handed)

Fig. 8 A-form of DNA (right handed)

Fig. 9 Z-form of DNA, (left handed)

Fig. 10 Comparison of A-, B-, and Z-forms of DNA

Fig. 11 Comparison of A- and B-forms of DNA

Fig. 12 Comparison of the central axis of the A- and B-forms of DNA