In the Watson-Crick model for the DNA double helix (B form) the A-T and G-C base pairs share all but one of the following properties. Which is the exception? None of the proton-binding groups in the...

Extracted text: In the Watson-Crick model for the DNA double helix (B form) the A-T and G-C base pairs share all but one of the following properties. Which is the exception? None of the proton-binding groups in the purine and pyrimidine bases is in its charged or ionized form. The plane of the base pair is roughly perpendicular to the axis of the helix in each case. The number of hydrogen bonds formed between the two bases of the base pair is the same. O The distance between the two glycosidic (base-sugar) bonds is the same in both base pairs, within a few tenths of an angstrom.