Now in addition, on top of these two things, this plasmid also contains a beta galactosidase gene. And that is a very important gene because what this gene does so remember, a plasmid not only can contain a gene that gives a resistance to antibiotics, but it can also contain a gene that produces special proteins needed to break down different types of molecules in that cell. And what this gene actually does is it produces a special enzyme that allows that cell to break down a particular type of sugar molecule for energy. So as an energy source. Now what this gene also does is we can actually use that protein produced by this gene, we can react it with a special type of analog molecule and that will give us the color blue. So it will cause the solution to turn blue and that can be used as a very good visual marker to basically differentiate between those plasmids that did take up, those cells that did take up the plasma, those cells that did not.