Nucleic acids are one of the four types of biomolecules that are essential to all life forms (in addition to lipids, proteins, and carbohydrates). Nucleic acids include DNA (which stands for deoxyribose nucleic acid) and RNA (which is an abbreviation for ribonucleic acids). Nucleic acids are made of nucleotides. Nucleotides have three parts- a five-carbon sugar, a phosphate group, and one of five nitrogenous bases (adenine, thymine, uracil, guanine, and cytosine). DNA and RNA differ in that DNA contains the sugar deoxyribose, while RNA contains the sugar ribose. DNA and RNA also different in their nitrogenous bases. In DNA, adenine pairs with thymine and guanine pairs with cytosine. In RNA, adenine pairs with uracil and guanine pairs with cytosine. Additionally, RNA and DNA are different because RNA is single stranded with DNA has a double-stranded helix structure.