I know this is very elementary and any high school student must be knowing the differences between RNA and DNA. But I feel a blog which deals with diverse aspects of molecular biology and biotechnology deserves a mention of basic differences between the two molecules.
DNA is double helical; RNA is single helical.
DNA contains deoxyribose pentose sugar (2′-deoxy-D-ribose); RNA has D-ribose sugar. The oyxgen from 2′ carbon of the pentose sugar is absent in deoxyribose sugar.
Both type of pentoses occur in their β-furanose (closed five-membered ring) form.
DNA, thus, consists of deoxyribonucleoside 5′-monophosphates (deoxyribonucleotides); RNA has ribonucleoside 5′-monophosphates (ribonucleotides).
DNA contains adenine (A), guanine (G), cytosine (C) and thymine (T) bases; RNA has adenine (A), guanine (G), cytosine (C) and uracil (U) bases. Thymine is not found in RNAs.
DNA is the genetic material in all organisms; however, RNA forms the genetic material in certain viruses like SARS, influenza, hepatitis C, retroviruses, etc.