Which structural characteristic is seen in rna but not in dna?

As for this question, we would tackle more on its bases. Basically, RNA and DNA differ both in their backbone. Both has a phosphate backbone but the DNA has a deoxyribose backbone while the RNA has a ribose one. Also about their bases which are, by the way, nitrogenous, both RNA and DNA have similar number of nitrogenous bases which is 4. They both have 3 the same nitrogenous bases which are guanine, adenine, and cytosine. The 4th nitrogenous base for DNA would be thymine while the 4th nitrogenous base for RNA would be uracil.

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