How can we help?

You can also find more resources in our Help Center.

77 terms

Unit 9 - Ecology

scientific study of interactions among organisms and between organisms and their environment
an individual living thing
a group of organisms of the same species populating a given area
all of the populations in an ecosystem
living and nonliving things in an environment, together with their interactions
part of Earth in which life exists including land, water, and air or atmosphere
the solid part of the earth consisting of the crust and outer mantle
all the water at and near the surface of the earth, 97% of which is in oceans
the mass of air surrounding the Earth
of or relating to living organisms
any nonliving component of an environment
limiting factor
anything that restricts the number of individuals in a population
a major biotic community characterized by the dominant forms of plant life and the prevailing climate
a vast, level, treeless plain in the arctic regions. The ground beneath the surface of the tundras is frozen even in summer
a flat grassland in tropical or subtropical regions
temperate deciduous forest
forest in a temperate region, characterized by trees that drop their leaves annually
A biome dominated by grasses and associated herbaceous plants
A type of biome characterized by low moisture levels and infrequent and unpredictable precipitation. Daily and seasonal temperatures fluctuate widely
tropical rain forest
biome near the equator with consistant warm temperatures, wet weather, and lush plant growth
coniferous forest
forest populated by cone-bearing evergreen trees; mostly found in northern latitudes
Thick, dense, thorny evergreen shrub found in Mediterranean climates
pertaining to water
population density
number of individuals per unit area
carrying capacity
largest number of individuals of a population that a given environment can support
animal that hunts and eats other animals
animal hunted or caught for food
the struggle between organisms to survive in a habitat with limited resources
the type of environment in which an organism or group normally lives
organism's role, or job, in its habitat
symbiotic relationship
an interaction between two or more species that live together in direct contact
symbiotic relationship in which one organism lives in or on another organism (the host) and consequently harms it
symbiotic relationship in which both species benefit from the relationship
symbiotic relationship in which one member of the association benefits and the other is neither helped nor harmed
ecological succession
(ecology) the gradual and orderly process of change in an ecosystem brought about by the progressive replacement of one community by another until a stable climax is established
pioneer organism
the first organisms in an ecological succession that work the land
Symbiotic association between a fungus and a photosynthetic organism
climax community
a relatively stable long-lasting community reached in a successional series
primary succession
the series of changes that occur in an area where no soil exists
secondary succession
ecological succession following a disturbance that destroys a community without destroying the soil
an organism that makes its own food; also called a producer
an organism that gets its energy from sunlight
an organism that gets its energy from chemicals taken from the environment
organism that obtains energy from the foods it consumes; also called a consumer
organism that obtains energy by eating only plants
organism that obtains energy by eating animals
any animal that feeds on dead animals
a consumer that eats both plants and animals
an organism that gets energy by breaking down the remains of dead organisms or animal wastes and consuming or absorbing the nutrients
food chain
series of steps in an ecosystem in which organisms transfer energy by eating and being eaten
food web
network of complex interactions formed by the feeding relationships among the various organisms in an ecosystem
an organism that makes its own food; also called an autotroph
primary consumer
An organism that eats producers
secondary consumer
An organism that eats primary consumers
tertiary consumer
An organism that eats secondary consumers
pyramid of energy
an ecological pyramid that shows the energy flow through each trophic level in an ecosystem.
trophic level
feeding level in an ecosystem
water cycle
the continuous process by which water moves from Earth's surface to the atmosphere and back
carbon oxygen cycle
The movement of carbon and oxygen through the environment. Involves respiration, photosynthesis, decomposition, burning of oxygen, and plants and animals.
nitrogen cycle
the transfer of nitrogen from the atmosphere to the soil, to living organisms, and back to the atmosphere
renewable resources
resources that can be replaced in a relatively short period of time (food, solar energy, oxygen)
nonrenewable resources
resources that cannot be replaced in a short amount of time, people will use them up before they can be replaced by nature (fossil fuels, minerals, old growth forests)
Three R's
Reduce, reuse, recycle
The process of stripping the land of its trees
greenhouse effect
natural situation in which heat is retained in Earth's atmosphere by carbon dioxide, methane, water vapor, and other gases
global warming
An increase in the average temperature of the earth's atmosphere (especially a sustained increase that causes climatic changes)
acid rain
rain containing acids that form in the atmosphere when industrial gas emissions (especially sulfur dioxide and nitrogen oxides) combine with water
Release of harmful materials into the environment
biological magnification
process by which pollutants become more concentrated in successive trophic levels of a food web
ozone depletion
caused by CFCs, methyl chloroform, carbon tetrachloride, halon, methyl bromide all of which attack stratospheric ozone. Negative effects of ozone depletion include increased UV, skin cancer, cataracts, and decreased plant growth.
the diversity of plant and animal life in a particular habitat (or in the world as a whole)
invasive species
species that enter new ecosystems and multiply, harming native species and their habitats
practice of harvesting or hunting to such a degree that remaining individuals may not be able to replenish the population
the preservation and careful management of the environment and of natural resources
thermal pollution
harm to lakes and rivers resulting from the release of excessive waste heat into them
air pollution by a mixture of smoke and fog, it makes a grey/brown haze
The process by which wind, water, ice, or gravity transports soil and sediment from one location to another
alternatives that must be given up when one is chosen over another