List the non-membrane cell organelles.

Organelles can be roughly divided into two types: membrane and non-membrane. Non-membrane structures appeared much earlier. They are found in prokaryotic cells and can also be found in eukaryotic cells. The variety of non-membrane organelles is rather small. First of all, these are ribosomes that carry out protein synthesis. Also, the cell center belongs to non-membrane organelles. There are also external organelles that are needed for cell movement. These are cilia and flagella. They are found in bacteria and protozoa.