What Are the Six Kingdoms in Biological Classification?

The six kingdoms in biological classification of organisms are Animalia, Plantae, Fungi, Protista, Archaeabacteria/Archaea and Eubacteria/Bacteria. Organisms are placed in different classifications based on similarities in features such as cell type, metabolism and reproduction. In biology, kingdom is the second largest taxanomic rank, beneath domain.

The kingdom Animalia includes organisms such as mammals, insects, amphibians, worms, and sponges. Organisms in this kingdom require oxygen for metabolism, acquire nutrition through ingestion, have eukaryotic cells, and reproduce sexually. Kingdom Plantae includes all plants and mosses, which photosynthesize for nutrition, require oxygen for metabolism, reproduce either through mitosis or sexually, and have eukaryotic cells.

Kingdom Fungi includes fungi, yeasts and molds. These organisms require oxygen for metabolism, reproduce asexually or sexually, acquire nutrition through absorption, and have eukaryotic cells. Organisms in the kingdom Protista include algae, slime mold, euglena, diatoms and amoebaes. They require oxygen for metabolism, acquire nutrition through absorption, ingestion or photosynthesis, reproduce asexually or through meiosis, and have eukaryotic cells.

The Eubacteria kingdom includes bacteria, blue-green algae and actinbacteria. Organisms in the Eubacteria kingdom reproduce asexually, have prokaryotic cells, and acquire nutrition through absoprtion, photosythesis or chemosynthesis. Kingdom Archaeabacteria includes methanogens, halophiles, psychrophiles and thermophiles. Such organisms may require oxygen, hydrogen, sulfur, carbon dioxide or sulfide for metabolism, reproduce asexually, and have various means of nutrition acquisition.