Chapter 6 Vocab

Habitat

An area where an organism lives including the biotic and abiotic factors that affect it.

Tolerance

The ability of an organism to survive and reproduce under circumstances that differ from their optimal conditions.

Niche

The full range of physical and biological conditions in which an organism lives and the way in which the organism uses those conditions.

Resource

Any necessity of life, such as water, nutrients, light, food, or space.

Competitive exclusion principle

The principle that states that no two species can occupy the same niche in the same habitat at the same time.

Keystone species

A single species that is not usually abundant in a community yet exerts strong control on the structure of a community.

Symbiosis

A relationship in which two species live close together.

Commensalism

A symbiotic relationship in which one organism benefits and the other is neither helpful nor harmed.

Mutualism

A symbiotic relationship in which both species benefit from the relationship.

Parasitism

A symbiotic relationship in which one organism lives on or inside another organism and harms it.

Ecological succession

A series of gradual changes that occur in a community following a disturbance.

Primary succession

Succession that occurs in an area in which no trace of a previous community is present.

Pioneer species

The first species to populate an area during succession.

Secondary succession

Type of succession that occurs in an area that was only partially destroyed by disturbances.

Biodiversity

The total of the variety of organisms in the biosphere; also called biological diversity.

Ecosystem diversity

Variety of habitats, communities, and ecological processes in the biosphere.

Species diversity

The number of different species that makes up a particular area.

Genetic diversity

The sum total of all the different forms of genetic information carried by a particular species, or by all organisms on earth.

Resilience

The ability to recover after a disturbance; the ability to deal with change and move on.

Ecosystem services

The benefits for humans that are provided by healthy ecosystems.