Domains and kingdoms

Science

Definition

The three-domain system classifies all life into Bacteria, Archaea, and Eukarya based on fundamental cellular differences. Within Eukarya, organisms are further classified into kingdoms including Protista, Fungi, Plantae, and Animalia.

Examples

  • Bacteria and Archaea are both prokaryotic but differ in cell wall composition and genetics
  • Mushrooms belong to Kingdom Fungi in Domain Eukarya
  • Extremophiles living in hot springs belong to Domain Archaea

Related Terms

Binomial nomenclature Prokaryotes vs eukaryotes Phylogenetic trees Characteristics of life

Study This Concept

Practice domains and kingdoms with free review games in these units:

Biology Unit 6: Classification and Taxonomy