How exactly do the properties of water, the solvent found in the nucleus, affect the structure of that DNA molecule? How does it lead to a double helix formation? So basically, outside this DNA molecule are a bunch of water molecules. So this is a water molecule, this is a water molecule and so forth. Now this is the oxygen and these are the age groups. So we know that the age groups, because of the polarity of water, the age groups will be partially positive and our oxygen groups will be partially negative.