RNA consists of one polynucleotide chain. RNA are also made up of four different monomers, but their nucleotides differ from those of DNA. In RNA, nucleotides are named ribonucleotides, wheres in DNA, deoxyribonucleotides. RNA contain ribose rather than deoxyribose, and instead of base thymine, RNA uses the base uracil (U). The other three bases are the same as in DNA.