Microbial world Organisms Infectious agents (living) (non-living) Prokaryotes eukaryotes viruses viroids prions (unicellular) Eubacteria Archaea Algae Fungi Protozoa Other (unicellular (unicellular (unicellular) (multicellular or or organisms) multicellular) multicellular)Microbial world Organisms (living) Infectious agents (non-living) Prokaryotes (unicellular) eukaryotes viruses viroids prions Eubacteria Archaea Algae (unicellular or multicellular) Fungi (unicellular or multicellular) Protozoa (unicellular) Other (multicellular organisms)