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 rough ER 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.

What does rough ER specialize in?

Rough ER lies immediately adjacent to the cell nucleus, and its membrane is continuous with the outer membrane of the nuclear envelope. The ribosomes on rough ER specialize in the synthesis of proteins that possess a signal sequence that directs them specifically to the ER for processing.