Classification and Taxonomy Lecture Notes

Vocabulary flashcards covering the fundamentals of biological classification, taxonomic history, and species identification methods.

Taxonomy

The scientific study of naming, defining and classifying groups of biological organisms based on shared characteristics.

Aristotle's Kingdom Plantae

A group classified over 2,000 years ago as organisms that make their own food, subdivided by size into herbs, shrubs, and trees.

Aristotle's Kingdom Animalia

A group classified over 2,000 years ago as organisms that do not make their own food, move, and are grouped by where they live: land, sea, or air.

Euglena

An organism that both moves and uses photosynthesis, demonstrating why a simple two-kingdom system was insufficient.

Ernst Haeckel

A German Biologist who in 1866 classified micro-organisms into a third kingdom called Kingdom Protista.

Kingdom Protista

A taxonomic kingdom consisting of algae, protozoa, and slime and water moulds.

Kingdom Fungi

A kingdom containing mushrooms and moulds that were originally thought to be in Kingdom Plantae but do not use photosynthesis.

Kingdom Bacteria

Single-celled organisms that lack a nucleus and obtain energy from a wide range of environments; also known as Monera or Eubacteria.

Kingdom Archaea

A kingdom named in the 1990s consisting of microorganisms that live in extreme environments.

Domain Eukaryota

The domain that encompasses Kingdom Protista, Kingdom Fungi, Kingdom Plantae, and Kingdom Animalia.

Binomial Nomenclature

A system developed by Carolus Linnaeus to describe organisms using two-word names, usually in Latin or Greek.

Genus

The first word of a scientific name; it must be capitalized and italicized.

Species name

The second word of a scientific name; it must be all lower case and italicized.

Rank

The term used for each of the 8 taxonomic categories in the hierarchy.

Taxon

The specific name given to each rank within the taxonomic hierarchy.

Taxonomic Ranks (Correct Order)

Kingdom, Phylum, Class, Order, Family, Genus, Species.

Cladistics

Also known as a Phylogenetic Tree, this system shows evolutionary relationships and when groups diverged from a common ancestor based on DNA and RNA sequences.

Morphological Species Concept

A concept that distinguishes organisms based on what they look like; it is simple and easy to observe for fossils but complicated by mimicry or sexual dimorphism.

Biological Species Concept

Defines a species as members of a population that actually or potentially interbreed in nature; it is widely used but cannot be applied to asexual or fossil species.

Phylogenetic Species Concept

Defines a species as the smallest set of organisms that share an ancestor and have a distinct evolutionary history; it is best for microbes and genetic studies.

Dichotomous Key

A tool used to identify species by using two non-subjective questions at each stage to differentiate between organisms.