Describe the DNA helix structure proposed by Watson and Crick. What is the diameter of the helix ...

The DNA model contains two DNA polymer strands in a right-handed twist around a common axis. The strands are orientated in an antiparallel direction from 5 to 3 and 3 to 5. The backbone consists of alternating sugar-phosphate groups stabilized by phosphodiester bonds, and it is located on the outside of the helix. Complementary base pairs are stacked in the center of the helix and are stabilized by hydrogen bonds. There are three hydrogen bonds between G and C, but only two between A and T. Thus, GC-rich regions require higher temperatures to break the bonds. The base pairs, which are perpendicular to the axis, are stacked with 10 base pairs per turn and a helical repeat of 34 The overall diameter of the helix is 10 angstroms.