The two prokaryotic kingdoms are Eubacteria and Archaea. A prokaryote is a relatively simple single-celled organism; more complex organisms (including all multi-celled organisms) are eukaryotes. In comparison to eukaryotes, prokaryotes are relatively simple, single-celled organisms. Different groups of prokaryotes. Evolutionary relationships of bacteria and archaea. Extremophiles.
Classification. Phylogenetic and symbiogenetic tree of living organisms, showing the origins of eukaryotes and prokaryotes. The five-kingdom system of classification for living organisms, including the prokaryotic Monera and the eukaryotic Protista, Fungi, Plantae and Animalia is. In the recent past, scientists grouped living things into five kingdoms (animals, plants, fungi, protists, and prokaryotes) based on several criteria.
The domain Bacteria comprises all organisms in the kingdom Bacteria, the domain Archaea comprises the rest of the prokaryotes, and the domain Eukarya.