Both DNA and RNA are molecules related to protein coding in a cell. The basic structure has a carbon sugar backbone with 4 different nitrogenous bases. In DNA there are two of these strands connected by the alignment of base pairs using H bonds forming a double helix, but RNA is single stranded. The nitrogenous base pairs of DNA consist of Adenine to Thymine and Cytosine to Guanine. In RNA, however, Thymine is replaced with a smaller nitrogenous base called Uracil.