And so if the solution in a beaker becomes blue, that means the cells did not uptake that plasmid. But if the solution does not turn blue, that means the cells successfully uptook that particular plasma because this gene has been inactivated. And we'll talk more about different examples and different experiments that involved with these different plasmids in a future lecture. So basically, the field of recombinant DNA technology allows us to create these recombinant novel genes. But if we actually want to amplify or clone these genes, we have to use vectors. And one type of vector are bacterial plasmids, as discussed in this lecture.