DNA is the major information storage molecule in living cells, and billions of years of evolution have tested and refined both this wonderful informational molecule and highly specific enzymes that can either duplicate the information in DNA molecules or transmit this information to other molecules.
DNA consists of a linear polymer containing three types of molecule: an organic aromatic base, connected to a ribose sugar, with an inorganic phosphate linker. Two of these linear polymers associate via weak interactions called hydrogen bonds to form a double strand. The individual structures of the bases, ribose and phosphate and the way the hydrogen bonds form, forces this double strand to adopt a helical shape (the famous Watson-Crick double helix).
The data density of DNA is incredible-it is one of the most efficient digital data systems known to exist. Just like a string of binary data is encoded with ones and zeros , a strand of DNA is encoded with four bases, adenine, thymine, cytosine, and guanine; represented by the letters A, T, C and G respectively.
Another important property of DNA is its double stranded nature. The bases A and T, and C and G can bind together, forming base-pairs. This complementarity of DNA gives it a unique data structure for use in computation - error correction is one particularly good example.
This is an interactive 3-Dimensional view of a DNA molecule. You will need the chime plug-in to view it, available from MDL.