The endoplasmic reticulum can either be smooth or rough, and in general its function is to produce proteins for the rest of the cell to function. The rough endoplasmic reticulum

has on it ribosomes, which are small, round organelles whose function it is to make those proteins.

What does the ER do in the plant cell?

The endoplasmic reticulum (ER) is the port of entry of proteins into the endomembrane system, and it is also involved in lipid biosynthesis and storage.

What does the endoplasmic reticulum do for dummies?

Endoplasmic reticulum is a collection of tubes that make, package, and transport proteins and fats. Rough endoplasmic reticulum has protein-making ribosomes on its surface, so it helps make and process proteins. Smooth endoplasmic reticulum helps make and process lipids and helps detoxify drugs and alcohol.