Ch. 18 In-class Notes:
Finding Order in
Diversity
• Taxonomy is the discipline of classifying
organisms and assigning each one a universally
accepted scientific name.
• To minimize confusion when referring to a
species, scientific names are given to each
organism as it is discovered.
• In the 1700s, Carolus Linnaeus developed a
two-word naming system for organisms.
• Both words are italicized or underlined.
• The first word is the Genus name and is
capitalized, the second word is the species
name and is lowercased. Ex: Ursus americanus
• Domain
• Kingdom
• Phylum
• Class
• Order
• Family
• Genus
• Species
• Dear
• King
• Phillip
• Called
• Out
• For
• Good
• Soup
• The domain Bacteria has only one kingdom in
it: Kingdom Eubacteria.
• All are prokaryotes (no nucleus in cells)
• All are unicellular (single-celled)
• All have cell walls that contain peptidoglycan
• They can be autotrophic or heterotrophic
• Ex: Streptococcus, Escherichia coli
• The domain Archaea has only one kingdom in
it: Kingdom Archaebacteria.
• All are prokaryotes
• All are unicellular
• All have cell walls without peptidoglycan
• They can be autotrophic or heterotrophic
• Ex: Methanogens, halophiles
• The domain Eukarya has four kingdoms in
it: Kingdoms Protista, Fungi, Plantae, and
Animalia.
• All are eukaryotes (have a nucleus in cells)
• Some are unicellular, many are multicellular
• Cell walls vary
• They can be autotrophic or heterotrophic
• Ex: Giant kelp, mushrooms, trees, humans
• The kingdom Protista includes all protists,
such as Amoeba and Paramecium, as well as
slime molds and algae, such as giant kelp.
• All are eukaryotes
• Most are unicellular, some are colonial, some
are muliticellular
• Some have cell walls made of cellulose, some
have chloroplasts
• They can be autotrophic or heterotrophic
• The kingdom Fungi includes many
decomposers such as mushrooms and yeasts
• All are eukaryotes (have a nucleus in cells)
• Some are unicellular, most are multicellular
• Cell walls are made of chitin
• All are heterotrophic (can’t make own food)
• The kingdom Plantae includes nonmotile
photosynthetic plants such as mosses, ferns,
flowering plants, and trees.
• All are eukaryotes
• All are multicellular
• Cell walls are made of cellulose, all have
chloroplasts
• All are autotrophic (make their own food/energy)
• The kingdom Animalia includes multicellular
animals such as sponges, worms, insects, fish,
birds, reptiles, amphibians, and mammals.
• All are eukaryotes
• All are multicellular
• None have cell walls or chloroplasts
• All are heterotrophic