Proteins are mainly made on ribosomes in the cytoplasm of the cell, either floating freely or attached to the rough endoplasmic reticulum (RER).

Quick Scoop

  • In both prokaryotic and eukaryotic cells, ribosomes read messenger RNA (mRNA) and link amino acids together to form proteins.
  • In eukaryotic cells:
    • Free ribosomes in the cytoplasm make proteins that usually stay in the cytosol (inside the cell fluid) or go to the nucleus, mitochondria, etc.
* Ribosomes attached to the **rough** endoplasmic reticulum make proteins that are secreted, placed in the cell membrane, or sent to organelles like lysosomes.
  • After being made, many proteins are further processed and modified in the Golgi apparatus before reaching their final destination.

So if you see the question “proteins are made where in the cell?” , the safest basic answer is: on ribosomes in the cytoplasm (on free ribosomes and on the rough ER).

Information gathered from public forums or data available on the internet and portrayed here.