Biodiversity: The variety of organisms considered at all levels from populations to ecosystems.

 

Taxonomy: The science of describing, naming, and classifying organisms.

 

Taxon: Any particular group within a taxonomic system.

 

Kingdom: Largest category in Linnaeus's hierarchy of organization.

 

Domains: Categories above the kingdom level.

 

Phyla: Subsets below the kingdom level in the animal kingdom.

 

Divisions: Subsets below the kingdom level in the plant kingdom.

 

Species: The smallest grouping which contains only a single kind of organism.

 

Binomial Nomenclature: The system of two-part names.

 

Subspecies: Variations of a species that live in different geographic areas.

 

Systematics: Classifying organisms in terms of their natural relationships.

 

Phylogenetics: The analysis of the evolutionary or ancestral relationships among taxa.

 

Phylogenetic Diagram: Also called a phylogenetic tree in which scientists often represent their hypotheses; Looks like a family tree and has a branching pattern that indicates how closely related a subset of taxa are thought to be.

 

Cladistics: A system of phylogenetic analysis that uses shared and derived characteristics as the only criteria for grouping taxa.

 

Shared Characteristic: A feature that all members of a group have in common.

 

Derived Characteristic: A feature that evolved only within the group under consideration.

 

Clade: Group of organisms that includes an ancestor plus all of its descendants.

 

Cladogram: Phylogenetic diagram created by cladists.

 

Bacteria: Domain that is made up of small, single-celled prokaryotic organisms that usually have a cell wall and reproduce by cellular fission.  

 

Archaea: The second domain that also consists of prokaryotes; Have distinctive cell membranes and other unique bio-chemical and genetic properties.

 

Eukarya: The third domain that has the most familiar groups of organisms; Cells of these organisms are large and have a true nucleus and have complex cellular organelles. Domain includes plants, animals, fungi, and a variety of single-celled organisms. 

 

Eubacteria: Kingdom that aligns with the domain bacteria. 

 

Archaebacteria: Kingdom that aligns with the domain archaea.

 

Protista: One of the four kingdoms of eukaryotes; Members are called protists. This kingdom has been defined as those eukaryotes that are not plants, animals, or fungi.  

 

Fungi: The second kingdom of eukaryotes; Consists of eukaryotic, heterotrophic organisms that are unicellular or multicellular and that gain nutrients by absorbing rather than ingesting

 

Plantae: The third kingdom of eukaryotes; Consists of eukaryotic, multicellular plants. 

 

Animalia: The fourth kingdom of eukaryotes; Animals are eukaryotic, multicellular, and heterotrophic organ- isms that develop from embryos. Most animals have symmetrical body organization and move around their environment to find and capture food. 

 

Ecology: The study of interactions between organisms and the living and nonliving components of their environment. 

 

Interdependence: Trait in which all organisms interact with other organisms in their surroundings and with the nonliving portion of their environment. Their survival depends on these interactions. 

 

Ecological Models: Represents or describes the components of an ecological system; May be physical, conceptual, or mathematical

 

Biosphere: The broadest, most inclusive level of organization

 

Ecosystem: Makes up the biosphere; Includes all of the organisms and the non- living environment found in a particular place. 

 

Community: Includes only species of organisms; All the interacting organisms living in an area.

 

Population: Includes all the members of a species that live in one place at one time.

 

Habitat: Where an organism lives.

 

Biotic Factors: The living components of the environment

 

Abiotic Factors: The nonliving components of the environment; Physical and chemical properties of the environment

 

Tolerance Curve: A graph of performance versus values of an environmental variable

 

Acclimation: Process through which organisms adjust their tolerance to abiotic factors 

 

Linnean Classification: A method of organizing organisms based on bone structure, embryology, and biological molecules, which was originally proposed by Carolus Linnaeus. 

 

Conformer: Organisms that do not regulate their internal conditions. They change as their external environment changes.  

 

Regulator: Organisms that use energy to control some of their internal conditions. Regulators are able to keep an internal condition within a wide range of environmental conditions.  

 

Dormancy: A state of reduced activity during periods of unfavorable conditions. 

 

Migration: To move to a more favorable habitat than the one previously living in. 

 

Generalist: Species with broad niches. They can tolerate a range of conditions and use a variety of resources.  

 

Specialist: Species that have narrow niches and are not able to tolerate a wide range of conditions. 

 

Producer: Autotrophs that capture energy and use it to make organic molecules 

 

Consumer: Heterotrophs who obtain energy by consuming organic molecules made by other organisms. 

 

Herbivore: Heterotrophs who consume producers. 

 

Carnivore: Heterotrophs who eat other consumers. 

 

Omnivore: Heterotrophs who consume both producers and consumers. 

 

Detritivore: Consumers that feed on the waste of the ecosystem, including dead organisms, fallen leaves, and animal wastes. 

 

Decomposer: Consumers that decay organic molecules from complex to simpler molecules.

 

Niche: The specific role or way of life of a species within its environment, which includes the range of conditions that the species can tolerate, the resources

it uses, the methods by which it obtains resources, the number of offspring it has, its time of reproduction, and all other interactions with its environment. 

 

Food Chain: A single pathway of feeding relationships among organisms in an ecosystem that results in an energy transfer 

 

Food Web: The interrelated food chains in an ecosystem

 

Trophic Level: Indicates the organism's position in a sequence of energy transfers

 

Gross Primary Productivity: The rate at which producers in an ecosystem capture the energy of sunlight by producing organic compounds

 

Net Primary Productivity: The rate at which biomass accumulates

 

Biomass: The organic material that has been produced in an ecosystem