& GC Base Pairs

A+T & G+C pairs have similar structures

The combination of a two-ring purine (A or G) and a single-ring pyrimidine (T or C) forms a base pair (
A+T or G+C ) with three co-planar rings.

A+T pair has two H-bonds versus the G+C pair with three .

All text material © 2014 by Steven M. Carr