We can also cleave proteins in eukaryotic cells post translationally. And these things cannot be done inside prokaryotic cells. So prokaryotic cells simply don't have the machinery, they don't have the Golgi apparatus and other organelles to basically modify the proteins posttranslationally. And what that means is the second method described here, producing eukaryotic proteins by introducing eukaryotic genes into prokaryotic cells cannot be done for all eukaryotic proteins because of what we just described. And that leads us directly to the next question. Can we actually introduce foreign eukaryotic genes into other eukaryotic cells?