In order to determine the sugar molecule associated with the nucleic acid, we must first determine if the nucleic acid is a deoxyribose nucleic acid (DNA) molecule or a ribonucleic acid (RNA) molecule. We can determine this by looking at the bases in the molecule, as DNA has thymine and RNA has uracil. After the type of molecule is determined, the nature of the sugar is given by the name. DNA has deoxyribose and RNA has ribose