Taxonomy and Classification

Flashcards based on lecture notes about taxonomy and classification of organisms.

Taxonomy

The science of classifying organisms.

Aristotle

Credited with developing the first taxonomic system.

Carolus Linnaeus

A Swedish botanist and naturalist who created a classification system based on physical similarities and differences.

Linnaeus's 7 Classification Taxons

Kingdom, Phylum (Division), Class, Order, Family, Genus, Species

Three Domains of the Modern Classification System

Archae, Bacteria, and Eukarya

Kingdoms within Domain Eukarya

Animalia, Plantae, Fungi, and Protista

Kingdom within Domain Archae

Archaebacteria

Kingdom within Domain Bacteria

Eubacteria

Binomial Nomenclature

The scientific name of an organism, comprised of the genus and species name.

Subspecies

Differing population groups within a single species, often found in species with wide geographical ranges.

Phylogeny

The study of the evolutionary history of a species.

Phylogenetic diagram or tree

Traces the evolutionary history of species and indicates their relationships.

Approaches to studying phylogeny

Fossil record, homologous organs, vestigial organs, and similarities in embryos and genetic sequences.

Cladistics

Classifies organisms based on shared and derived characteristics.

Shared characteristic

A feature that all members of a group have.

Derived characteristic

A feature present only in a particular group.

Clade

A group of species that share a common ancestor.

Kingdom Animalia

Multicellular eukaryotes that lack cell walls, plastids, and large storage vacuoles, capable of sexual reproduction, and heterotrophic.

Kingdom Plantae

Multicellular eukaryotes with cell walls (cellulose/pectin), plastids, and large storage vacuoles, capable of sexual reproduction, and autotrophic.

Kingdom Protista

Mostly unicellular eukaryotes, can be autotrophic or heterotrophic, and usually reproduce asexually.

Kingdom Fungi

Mostly multicellular eukaryotes with cell walls composed of chitin, heterotrophic decomposers that digest food externally.

Kingdom Eubacteria

Unicellular prokaryotes that reproduce asexually via binary fission and are generally aerobic.

Kingdom Archaebacteria

Unicellular prokaryotes with unique cell membranes and walls, capable of living in extreme environments.

Methanogens

Archaea that convert hydrogen gas and carbon dioxide into methane gas in anaerobic environments.

Extremophile Archaea

Microbes that can survive in extreme environments.

Halophiles

Bacteria that tolerate very high salt concentrations.

Thermoacidophiles

Organisms that thrive in extremely hot and acidic environments.

Psychrophiles (Cryophiles)

Survive at extremely low temperatures, such as within glacial areas.

Barophiles

Withstand extreme pressure (deep within the oceans)

Xerophiles

Survive in extremely dry environments

Alkaliphiles

Survive in very basic (alkaline) environments

Endoliths

Survive within the small pore spaces within rocks