which nitrogenous base is found in rna but not in dna?
Uracil is one of four nitrogenous bases found only in the RNA molecule: base pairing- uracil and cytosine (derived from pyrimidine) and adenine and guanine (derived from purine). Deoxyribonucleic acid (DNA) also contains each of these nitrogenous bases, except that thymine is substituted for uracil.