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15-1 Biological Classification

Binomial Nomenclature	Classification system in which each organism is given a two-part scientific name	-developed by Carolus Linnaeus -all names are in Latin -reduces ambiguity for scientists around the world -name is always italicized or underlined -genus name (first) is always capitalized and species name is never capitalized
Taxonomy	Science of naming organisms and assigning them to groups	-developed by Linnaeus -grouped ornaisms according to important physical features (or now genetic similarities) -evolution provides guiding philosophy and purpose to modern classification systems -taxonomists try to group organisms to show evolutionary relationships -do so by studying homologous structures in adult organisms, embryos and well-preserved fossils -may be organized by differences in DNA, RNA and cytochrome c
Taxon	Group into which organsims are classified	-according to physical features
Species	Group of organisms that share similar characteristics and can interbreed with one another to produce fertile offspring	-smallest taxon -only taxon that has clear biological identity
Genus	Group of closely related species	-contains species that are similar -ex. Felis domesticus, Felis concolor
Family	Group of closely related genera	-ex. Panthera, Felis, Acinonyx all belong to Felidae
Order	Group of closely related families	-ex. Carnivora, order for meat eating animals such as cats and dogs
Class	Group of closely related orders	-ex. Carnivora and other orders belong to Mammalia
Phylum	Group of closely related classes	-ex. mammals, birds, fish, reptiles belong to Chordata -there also sub-phylums
Kingdom	Group of closely related phyla	-largest taxon -five kingdoms: Monera, Protista, Fungi, Plantae, -Prokaryotic: Monera -Eukaryotic: Protista, Animalia, Plantae, Fungi

15-2 The Five-Kingdom System

Monera	Kingdom that includes prokaryotic organisms	-only prokaryotic kingdom -prokaryotic earliest life forms -prolarotes lack nuclei, mitochondria, chloroplasts -reproduced using binary fission -they are autotrophs or heterotrophs
Protista	Kingdom that includes all single-celled eukaryotic organisms	-differ from prokaryotes because they have a nucleus and membrane-bound organelles -further divided into three groups: plantlike protists, animallike protists, fungi like protists -division between protists and multicellular kingdoms is not clear cut -heterotrophs or autotrophs -food intake is by absorbtion, photosynthesis or ingestion
Fungi	Kingdom that includes heterotrphic organisms that build cell walls that typically do not contain cellulose	-do not always have seperate cells divided by complete cell walls -food intake is by absorbtion
Plantae	Kingdom that includes multicellular autotrophic organisms	-cell walls contain cellulose -photosynthesis using chlorophyll -food intake is by absorbtion
Animalia	Kingdom that contains multicellular heterotrophic organisms whose cells lack cell walls	-multicellular -heterotrophic -food intake is by ingestion -great diversity in animalia kingdom