What happens inside the eukaryotic cells is these intron segments are removed because the eukaryotic cells contain the proper proteins and the proper machinery inside the cell to actually carry out the process. But this does not exist inside prokaryotic cells such as bacterial cells. And this is a problem because if we take a Eukaryotic gene so let's suppose this is Eukaryotic DNA molecule and this colored portion is the gene within that eukaryotic DNA molecule that codes for some particular protein. The question is can we take this eukaryotic DNA, place it inside that prokaryotic bacterial cell in this form and expect that bacterial cell to be able to actually form any useful protein from this particular DNA? And the answer is no. And that's because once we take this molecule and place it inside that bacterial cell we have these intro sections shown in orange and these exxon sections shown in blue.