Although DNA and RNA are practically identical, there are a few key differences between the two molecules. Function: DNA stores long-term genetic information and transmits genetic information to make new organisms.RNA is used to transfer the genetic code to make proteins, from the nucleus to the ribosomes. Structure: DNA is a double stranded molecule, arranged in a double-helix structure. Whereas RNA is a single stranded molecule. Both are made up of nucleotides; each nucleotide contains a nitrogenous base, a 5-carbon sugar and a phosphate.Sugar: DNA contains a deoxyribose sugar, it has one less hydroxyl group than the ribose sugar. RNA contains a ribose sugar. Bases: DNA contains A T C and G (Adenine, Thymine, Cytosine and Guanine). RNA contains A C G and U (Adenine, Cytosine, Guanine and Uracil). In RNA Thymine is replaced by Uracil.