The basic building block of DNA is called nucleotide. A nucleotide is made up of one suger molecule, one phosphate molecule, and one of the four bases.
Each RNA nucleotide consists of three parts: a suger a phosphate group, and a nitrogen-consisting base. The four RNA bases are adenine, uracil, guanine, and cytosine also reffered to as A, U, G, and, C. RNA shares three bases in common with DNA: adenine, guanine, and cytosine. Instead of uracil, DNA contains thymine.
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