DNA vs. RNA
What's the difference between DNA and RNA?
Both DNA and RNA are composed of repeating units of nucleotides. Each
nucleotide consists of a sugar, a phosphate and a nucleic acid base.
The sugar in DNA is deoxyribose. The sugar in RNA is ribose, the same
as deoxyribose but with one more OH (oxygen-hydrogen atom combination
called a hydroxyl). This is the biggest difference between DNA and RNA.
Another difference is that RNA molecules can have a much greater variety
of nucleic acid bases. DNA has mostly just 4 different bases with a few
extra occasionally. The difference in these bases (between DNA and RNA)
allows RNA molecules to assume a wide variety of shapes and also many
different functions. DNA, on the other hand, serves as a set of directions
and that's about all (but that's absolutely necessary!).
Click here to return to the Biology Archives
Update: June 2012