These are the heating elements of our distilled water (dH2O) supply. Water is heated to vapor and condensed into a 12 gallon glass jar. We use the purified water for making solutions that do not require absolute purity or will be sterilized later, like TAE Buffer or LB medium. TAE Buffer is used when separating DNA with gel electrophoresis. It contains EDTA (Ethylenediaminetetraacetic acid, what a tedious name!) which chelates (binds/sequesters) metal ions that are required by enzymes that degrade DNA. So, it protects DNA from degradation in solution. TAE is not used for long term storage of DNA, so it is not vital that that the water be nuclease free. LB is a well documented growth medium for bacteria, especially E. coli. We use it for growing E. coli cultures. Once the medium is mixed into solution it will be sterilized in the autoclave so the sterility of the dH2O is not an issue.