the part of the earth's crust, waters, and atmosphere that supports life
carrying capacity
The maximum population of a particular organism that a given environment can support
commensalism
A symbiotic relationship between two organisms of different species in which one derives some benefit while the other is unaffected.
community
A group of plants and animals living and interacting with one another in a specific region under relatively similar environmental conditions.
consumer
A heterotrophic organism that feeds on other organisms in a food chain.
ecology
the branch of biology dealing with the relations and interactions between organisms and their environment, including other organisms.
ecosystem
a system formed by the interaction of a community of organisms with their environment
habitat
the natural environment of an organism
limiting factor
an environmental factor that tends to limit population size
mutualism
a relationship between two species of organisms in which both benefit from the association.
niche
The function or position of an organism or population within an ecological community.
parasitism
A symbiotic relationship in which one organism (the parasite) benefits and the other is harmed
population
All the organisms that constitute a specific group or occur in a specified habitat.
producer
an organism, as a plant, that is able to produce its own food from inorganic substances.
symbiosis
the living together of two dissimilar organisms, as in mutualism, commensalism, amensalism, or parasitism.
predator
An organism that lives by preying on other organisms
prey
an animal hunted or seized for food
competition
the struggle among organisms, both of the same and of different species, for food, space, and other vital requirements
chemosyntesis
the synthesis of organic compounds within an organism, with chemical reactions providing the energy source.
food web
a series of organisms related by predator-prey and consumer-resource interactions; the entirety of interrelated food chains in an ecological community.
energy pyramid
a depiction of the amount of energy in each trophic level of an ecosystem
food chain
a series of organisms interrelated in their feeding habits, the smallest being fed upon by a larger one, which in turn feeds a still larger one
