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52 Cards in this Set

  • Front
  • Back
nonliving factors that influence the life and activities of an organism
abiotic factors
any accumulation of organic material produced by living things
living portions of the environment
biotic factors
the cyclic flow of carbon from the atmosphere to living organisms and back to the atmospheric reservoir
carbon cycle
animals that eat other animals
two or more species of organisms reciprocally influencing the evolutionary direction of the other
the relationship between organisms in which one organism benefits while the other is not affected
interacting groups of different species
an interaction between two organism in which both require the same limited resource, which results in harm to both
which states that no two species can occupy the same ecological niche in the same place at the same time
competitive exclusion principle
organisms that use other organisms as food
small organisms, like bacteria and fungi, that cause the decay of dead organic matter and recycle nutrients
bacteria that convert nitrogen compounds into nitrogen gas
denitrifying bacteria
tiny particles of organic material that result from fecal waste material or the decomposition of plants and animals
a branch of science that deals with the interrelationship between organisms and their environment
a group of interacting species along with their physical environment
a parasite that is adapted to live on the outside of its host
a parasite that is adapted to live within a host
everything that affects an organism during its lifetime
a change in structure, behavior, or physiology of a population of organisms as a result of some organisms with favorable characteristics having greater reproductive success than those organisms with less favorable characteristics
the death of a species; the elimination of all the individuals of a particular kind
the series of organisms involved in the passage of energy from one trophic level to the next
food chain
intersecting and overlapping food chains
food web
bacteria that live in the soil and can convert nitrogen gas in the atmosphere into forms that plants can use
free-living nitrogen-fixing bacteria
the specific kind of place where a particular kind of organism lives
primary consumers; animals that eat plants
the organism a parasite uses for its sources of food
competition between members of different species for a limited resource
interspecific competition
competition among members of the same species for a limited resource
intraspecific competition
one that has a critical role to play in the maintenance of specific ecosystems
keystones species
the one primary condition of the environment that determines population size of an organism
limiting factor
the association between organisms in which both benefit
root-fungus associations
a process that determines which individuals within a species will reproduce more effectively and therefore results in changes in the characteristics within a species
natural selection
the total role an organism plays in its ecosystem
The series of stages in the flow of nitrogen in ecosystems
nitrogen cycle
Bacteria that are able to convert ammonia to nitrate which can be converted to nitrate.
nitrifying bacteria
Bacteria that are able to convert the nitrogen gas in the atmosphere into forms that plants can use.
nitrogen-fixing bacteria
Animals that eat both plants and other animals.
An organism adapted to survival by using other living organisms for nourishment.
A relationship between organisms in which one, known as the parasite, lives on or in the host and derives benefit from the relationship while the host is harmed.
occurs when a predator kills and eats its prey
An animal that kills and eats another organism
An organism that is killed and eaten by a predator
An animal that eats plants directly
primary consumer
An organism that can manufacture food from inorganic compounds and light energy
The ability organisms have to succeed under a variety of environmental conditions. The breadth of this tolerance is an important ecological characteristic of a species.
range of tolerance
Animals that eats animals that have eaten plants
secondary consumer
A group of organisms that can interbreed and produce offspring capable A close, long-lasting physical relationship between members of two different species
Bacteria that grow within a plants root system and that can convert nitrogen gas from the atmosphere to nitrogen compounds that the plant can use.
symbiotic nitrogen-fixing bacteria
A stage in the energy flow through ecosystems
trophic level
An organism that carries a disease from one host to another