All of the following are part of a prokaryotic cell except

An Endoplasmic reticulum

Explanation:

A living organism can either have prokaryotic or eukaryotic cells.

Eukaryotic cells have a defined nucleus and other membrane bound organelles whereas prokaryotic cells lack membrane bound organelles such as mitochondrion and chloroplast.

Endoplasmic reticulum are membranous system that forms a system of flattened sacs in the cytoplasm.

These organelles can only be found in eukaryotic cells and not prokaryotic cell.