The Six Kingdoms An Overview

Before the six kingdoms, there were… After Linnaeus created his two-word naming system, scientists only recognized 2 kingdoms Plantae (plants) & Animalia (animals) Because of the increase in knowledge of living organisms and the invention of the microscope, biologists have added complexity and detail to the classification system

Before the six kingdoms, there were… In the 1800’s, scientists noticed differences between prokaryotes and eukaryotes, so they added a kingdom for the prokaryotes Then, there were 5 kingdoms Monera (prokaryotes), Protista, Fungi, Plantae & Animalia In the 1900’s, scientists noticed two major groups of prokaryotes in the Kingdom Monera

The Six Kingdoms Today: Eubacteria Archaebacteria Protista Fungi Plantae Animalia DOMAIN BACTERIA DOMAIN ARCHAEA DOMAIN EUKARYA The 6 Kingdoms are sorted into 3 domains because scientists see major differences among them

What about Viruses? Viruses don’t have a place in the Linnaean classification system because they are not considered living – they are missing key characteristics of living organisms For example, viruses do have genetic material, but they cannot reproduce on their own. Viruses reproduce by infecting cells.

Major Characteristics that define Kingdoms and Domains Cell Type (prokaryotic or eukaryotic) Cell Structure (cell walls or no cell walls) Number of Cells (unicellular or multicellular) Nutrition (autotroph or heterotroph) Reproduction (asexual or sexual)

Domain: Bacteria Kingdom: Eubacteria Common name is bacteria Cell type: prokaryotic Cell structure: cell wall with peptidoglycan Number of cells: unicellular Nutrition: autotrophic or heterotrophic Mode of reproduction: asexual - binary fission Other information: Most are beneficial Examples: E. coli & Streptococcus pneumoniae

Domain: Archaea Kingdom: Archaebacteria Common name is archaea Cell type: prokaryotic Cell structure: cell wall with unique lipids Number of cells: unicellular Nutrition: autotrophic or heterotrophic Mode of reproduction: asexual - binary fission Other information: live in extreme environments Examples: Staphylothermus marinus

Domain: Eukarya Kingdom: Protista Common name is protists Cell type: eukaryotic Cell structure: some species have cell wall Number of cells: unicellular or multicellular Nutrition: autotrophic or heterotrophic Mode of reproduction: sexual & asexual Other information: not a natural group but a “left-over” taxon. Most are marine. Examples: paramecium

Domain: Eukarya Kingdom: Fungi Common name is Fungi Cell type: eukaryotic Cell structure: cell walls with chitin Number of cells: mostly multicellular Nutrition: heterotrophic by absorption Mode of reproduction: sexual Other information: Some fungi taste great and others can kill you Examples: mushrooms, mold & mildew

Domain: Eukarya Kingdom: Plantae Common name is Plants Cell type: eukaryotic Cell structure: cell walls with cellulose Number of cells: multicellular Nutrition: autotrophic Mode of reproduction: sexual & asexual Other information: range from tiny mosses to giant trees Examples: flowering plants

Domain: Eukarya Kingdom: Animalia Common name is Animals Cell type: eukaryotic Cell structure: no cell walls Number of cells: multicellular Nutrition: heterotrophic by ingestion Mode of reproduction: sexual Other information: found in every type of environment (air, water, land…) Examples: bottle-nose dolphin, monarch butterfly