Prokaryotic and eukaryotic cells differ in many ways, notably in the structure of their cell walls, the arrangement of their genetic material and their internal arrangement of cellular machinery. Eukaryotes, a group that encompasses all large organisms, also tend to reproduce sexually, while prokaryotes show more variation in reproductive methods.
Prokaryotic cells tend to be smaller than eukaryotic cells. Typical prokaryotes range in size between 0.2 and 2 nanometers, while eukaryotes can be up to 50 times larger. Eukaryotic cells are distinguished by the existence of a true nucleus and multiple internal structures called organelles. Prokaryotic cells lack a nucleus, and membraneous organelles are totally absent. Most prokaryotic cells have a chemically complex cell wall, but eukaryotic cells either have no wall or a chemically simple one. Eukaryotic cells incorporate carbohydrates into their plasma membranes and use sterols as messenger structures. Prokaryotes do not use carbohydrates in this way, and they rarely use sterols.
The genes of eukaryotic cells are arranged in a linear fashion along multiple chromosomes, while prokaryotes posses only a single, ring-shaped chromosome. This might be related to their very different methods of reproduction. Prokaryotes do not engage in meiosis, but reproduce via simple binary cell division.