Outline the key structural differences between mRNA and DNA molecules and how do these contribute to their different functions?

DNA is a double stranded nucleotide polymer that is configured as a double helix, whereas RNA is a single-stranded polymer that can form secondary structures. This double-stranded nature contributes to the long-term stability of a DNA molecule. The use of the deoxyribose sugars in DNA (instead of ribose as in RNA) also contributes to this stability as deoxyribose has one fewer hydroxyl group which makes the sugar less reactive. This stability is essential to the function of DNA as it enables the long-term storage of genetic information with limited degradation and mutation. Conversely mRNA does not need to be as stable a molecule as it only required for the synthesis of proteins in the short-term and its perpetual presence would represent an energy cost to the cell. Additionally RNA contains the base uracil instead of thymine as the complementary base to adenine.