What are three places where ribosomes occur in a cell?

Ribosomes can be found in

1) Cytoplasm

2) Mitochondria

3) On the surface of Endoplasmic Reticulum

Explanation:

In eukaryotes, ribosomes form within the nucleolus, a structure inside the cell's nucleus. As ribosomal proteins enter the nucleus, they join with four rRNA strands to form a whole ribosome. The subunits exit the nucleus through pores and start protein synthesis within the cytoplasm of the cell.