Then they move to their target location, their target cell. Now, the other pathway by which we attain these 20 amino acids is by breaking down the existing proteins that are found inside our body. So we have proteins found inside the cells as well as outside the cells. And these proteins can be broken down and recycled into amino acids. So we have many different types of proteins that exist as enzymes, and these enzymes must be inactivated. And sometimes, to inactivate an enzyme, we proteolytically cleavage, we destroy it, and then we recycle those amino acids.