Explanation:

- Ribosomes: Present in both prokaryotic and eukaryotic cells. They are essential for protein synthesis.

- Plasma membrane: Found in all cell types, prokaryotic and eukaryotic. It serves as a barrier, controlling the movement of substances in and out of the cell.

- Nuclear membrane: Found only in eukaryotic cells. It encases the nucleus, which contains genetic material.

- Cytoplasm: Present in both prokaryotic and eukaryotic cells. It's a jelly-like substance where cellular processes occur.