And these ubiquitous molecules, which are also proteins, are not actually broken down. So in step one, we ultimately see the 19s subunit recognizes the target protein because of the polyubiquidination that happens on that target protein. It binds to it and inserts it into the 20s core for degradation. Now, in that barrel core, we basically cleave the protein into small peptides and then we remove the ubiquitin. And that ubiquitin is recycled and reused by the cell. Now, what is the fate of these peptides?