Endoplasmic reticulum — Science definition
A folded network of membranes that processes proteins (rough ER, studded with ribosomes) and makes lipids (smooth ER).
Where it is taught
- Prokaryotic & Eukaryotic Cells & Their Organelles — Cells, Membranes & Exchange, Life Science: Biology, Grade 10
In use
Some ribosomes float free in the cytoplasm, but many dock on the endoplasmic reticulum, a vast folded membrane network that runs off the nucleus.
Prokaryotic & Eukaryotic Cells & Their Organelles
Questions using endoplasmic reticulum
Problem 1
Why is the rough endoplasmic reticulum described as 'rough'?
- It is studded with ribosomes that build and process proteins
- It has a jagged outer wall
- It stores rough, undigested food
- It contains chloroplasts
Answer and explanation
It is studded with ribosomes that build and process proteins
Ribosomes attached to its surface give the rough ER its bumpy look and its role in processing newly made proteins.