AAT Bioquest

What is the smallest cell organelle in a cell?

Posted February 9, 2023


The smallest cell organelles are ribosomes. Ribosomes are spherical, dense organelles that range only 20-30 nm in diameter. They are the smallest organelle in a cell based on their surface area size. All ribosomes are composed of a large and small subunit and carry out similar functions for protein synthesis; ribosomes are composed of nucleic acids and proteins. The large subunit exists on top of the small subunit, with an RNA template between the two. 

Additional resources

Ribosome Structure, Function, and Early Evolution

Cell Structures and Organelles

Nuclear Blue™ DCS1 *5 mM DMSO Solution*