The sugar back bone of RNA is composed of ribose molecules while DNA has deoxyribose (the sugar molecule is lacking a hydroxyl group at the 2' position as compared to ribose). DNA is made up of the nucleotides adenine, guanine, thymine, and cytosine. RNA is also made up of adenine guanine and cytosine, but utilizes uracil instead of thymine. RNA is commonly found to be single stranded as opposed to the double stranded DNA.