Topic 5.3 Classification of biodiversity

Archaeans

one of the prokaryotic domains of life. They tend to live in extreme environments, they have RNA polymerases and ribosomes that are closer to eukaryotes.

Bacteria

one of the prokaryotic domains of life, more diverse than archaeans.

Binomial nomenclature

agreed upon system for naming organisms consisting of genus and species.

Class

a subdivision of a phylum, a class is composed of one or more orders of organism.

Domains

one of the three major categories of life: archaea, bacteria, and eukarya.

Eukaryotes

one of the three domains of life, cells are compartmentalized.

Family

a subdivision of an order: composed of one or more genera.

Genus

a subdivision of a family: composed of one or more species.

Kingdom

a taxonomic group that contains one or more phyla.

Order

a subdivision of a class, composed of one or more families of organism.

Phylum

a subdivision of a kingdom, composed of one or more classes of organism.

Species

a group of related organisms that can successfully interbreed in the wild.

Taxon

a group of species which shares and evolutionary relationship.

Taxonomy

the science of classification.

Viruses

non-living biological entities that have infectious properties - non-living pathogens.