Base-Pairing Rules in DNA

    By playing with scale-models of the four DNA bases A C G & T, Watson & Crick realized that an A+T pair was structurally identical to a G+C pair. This would allow a series of such pairs to fit, in any order, into the space between the two sugar / phosphate backbones. This explains Chargaff's Rules, and incorporates Franklin's X-ray data for two helices, with the bases inside.

All text material © 2014 by Steven M. Carr