A   B   C   D   E   F   G   H   I   J   K   L   M   N   O   P   Q   R   S   T   U   V   W   X   Y   Z

Uracil is one of the four primary nucleotide bases that compose the information structure in the RNA molecule (the other three being Adenine, Guanine, and Cytosine). Uracil is the only primary base unique to RNA. It forms base pairs with Adenine, whereas in DNA Adenine pairs with a base called Thymine. The molecular structure of Uracil is C4H4N2O2