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A living thing


An environment that provides the things an organism needs to live, grow and reproduce

Biotic Factor

A living part of an organism's habitat


The process in which organisms use water along with sunlight and carbon dioxide to make their own food


A group of organisms that are physically similar and can mate with each other


All the different populations that live together in a particular area


The community of organisms that live in a particular area


The study of how living things interact with each other and their environment

Birth Rate

The number of births in a population in a certain amount of time

Carrying Capacity

the largest population that an area can support

Death Rate

The number of deaths in a population in a certain amount of time


Leaving a population


An approximation


Moving to a population

Limiting Factor

An environmental factor that causes a population to decrease

Population Density

The number of individuals in an area of a specific size


A behavior or physical characteristic that allows an organism to live successfully in its environment


A relationship between two species in which one species benefits and the other in neither helped nor harmed


The struggle between organisms to survive as they attempt to use the same limited resource


The organism that a parasite lives in or on in a parasitism interaction


A relationship between two species in which both species benefit

Natural Selection

A process by which characteristics that make an individual better suited to its environment become more common in a species


The role of an organism in its habitat, or how it makes its living


The organism that benefits by living on or in a host in a parasitism interaction


A relationship in which one organism lives on or in a host and harms it


An interaction in which one organism kills another for food


The organism that does the killing in a predation interaction


An organism that is killed and eaten by another organism


A close relationship between two species that benefits ar least one of the species

Pioneer Species

The first species to populate an area

Primary Succesion

The series of changes that occur in an area where no soil or organisms exist

Secondary Succession

The series of changes that occur in an area where the ecosystem has been disturbed, but where soil and organisms still exist


The series of predictable changes that occur in a community over time

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