Kingdoms and Domains 18 3 Domain Most inclusive

Kingdoms and Domains 18. 3

Domain • Most inclusive taxonomic category; larger than a kingdom.

Bacteria • Domain of unicellular prokaryotes that have cell walls containing peptidoglycan.

Eubacteria • Kingdom of unicellular prokaryotes whose cell walls are made up of peptidoglycan.

Archaea • Domain of unicellular prokaryotes that have cell walls that do not contain peptidoglycan.

Archaebacteria • Kingdom of unicellular prokaryotes whose cell walls that do not contain peptidoglycan.

Eukarya • Domain of all organisms whose cells have nuclei, including protists, plants, fungi, and animals.

Protista • Kingdom composed of eukaryotes that are not classified as plants, animals, or fungi.

Fungi • Kingdom composed of heterotrophs; many obtain energy and nutrients from dead organic matter.

Plantae • Kingdom of multicellular photosynthetic autotrophs that have cell walls containing cellulose.

Animalia • Kingdom of multicellular eukaryotic heterotrophs whose cells do not have cell walls.

Key Concept • What are the six kingdoms of life as they are now identified? – The six-kingdom system of classification includes the kingdoms Eubacteria, Archaebacteria, Protista, Fungi, Plantae, and Animalia.

Key Concept • What is the three-domain system of classification? – The three domains are the domain Eukarya, Which is composed of protists, fungi, plants, and animals; the domain Bacteria, which corresponds to the kingdom Eubacteria; and the domain Archaea, which corresponds to the kingdom Archaebacteria.