It is a spherical organelle with double membranes within the cell.
The nucleus controls all the functions inside the cell and also carries hereditary information.
There is a special site within the nucleus called the nucleolus that is involved in ribosome synthesis.
The nucleolus is a non-membrane-bound condensed region of chromatin.
This acts as the site for active ribosomal RNA synthesis.
Within the nucleolus, the proteins are imported from the cytoplasm. Thereafter, using rRNA they are assembled into large and small ribosomal subunits.
These subunits formed within the nucleolus exit the nucleus through nuclear pores into the cytoplasm where the large and small subunits can assemble into a ribosome.