1. In organisms, DNA is generally found as double-stranded, and RNA as single-stranded. 2. DNA has the deoxyribose pentose sugar, and RNA has the ribose pentose sugar. 3. DNA has thymine; RNA has uracil.his is the biggest difference between DNA and RNA. 3. Nitrogen Bases of DNA: Adenine Guanine Cytosine Thymine NItrogent bases of RNA: Adenine Guanine Cytosine Uracil.