Assembled in the nucleolus , then exported out through the nuclear pores *ribosomal(RNA)( rRNA) one of the macromolecules required for the synthesis of ribosomes is, manufactured in the nucleolus as well. *Function: carries out protein synthesis in two locations: In the cytosol-for proteins that will stay in the cell, these specific ribosomes are called "FREE RIBOSOMES" *attaches to the outside of the RER or the nuclear envelope for proteins destined for the plasma membrane or outside the cell, these are "BOUND RIBOSOMES" *location of the ribosomes is temporary-ribosomes move from free state to a "bound state or vie versa depending on the protein that is being made.