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what are the four bases of dna and rna
The bases A, G, C, and T are found in DNA while A, G, C, and U are found in RNA.
what is the proper term for the bases of dna and rna
Nucleobases, also known as nitrogenous bases or often simply bases, are nitrogen-containing biological compounds that form nucleosides.

Question: is the T and U almost identical
Self-contained rewrite: are thyamine and uracil almost identical