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law of 10%

only 10% of the energy gets passed on to the next trophic level in a food chain


the process of obtaining information using the senses; fact


an explanation for an observation


a testable explanation for an observation

independent variable

the variable that you are changing/manipulating

dependent variable

the variable that is measured in an experiment; changes due to the independent varable

control group

in an experiment, the standard that is used for comparison; usually the group that you keep normal


the factors that remain the same in an experiment (ex. time, amount of water, etc.)

abiotic factors

nonliving things found in the environment

biotic factors

living things found in the environment

natural selection

"reproduction of the fittest;" process where the individuals best suited for the environment survive, reproduce, and pass along their superior genes


a living thing

pesticide resistance

when a species is no longer affected by the pesticide; happens due to natural selection

food web

diagram that shows all of the feeding relationships between organisms in an ecosystem

food chain

a linear path that shows the flow of energy from one organism to another


consumer that only eats meat


consumer that only eats plants


consumer that eats meat and plants


organism that gets its energy by eating another organism


organism that makes its own energy (usually by photosynthesis)

trophic level

step on food chain/pyramid where organism eats

cellular respiration

process by which organisms get energy from food (opposite of photosynthesis)


removal of soil by water, wind, or plowing


upper layer of soil containing a large portion of organic matter and nutrients

persistent pesticide

a pesticide that doesn't break down easily and remains in the ecosystem for a long time


loss of topsoil that makes land no longer fertile

integrated pest management

aims to reduce pests with minimal environmental damage


land that is able to grow crops


genetically modified organism; takes a favorable trait from one organism and puts it into another organism in order to make it better

no-till farming

does not overturn soil and plants seeds directly in last years cover crop; causes less erosion


production of crops and livestock by farming


any living organism that is found where it is not wanted and is causing damage


something that kills a pest

biological pesticide

a living organism that can be used to get rid of a pest

point source pollution

pollution that comes from one source that you can point to

nonpoint source pollution

pollution that comes from multiple sources so the source can't be identified

impervious surfaces

surface, such as a parking lot, street, or sidewalk that won't allow water to absorb into the ground


area of land that drains to one place

genetic pollution

when an invasive species takes over in an area so that the native species can no longer live

thermal pollution

water that gets heated up when it is used during the cooling process at a powerplant


rain that doesn't percolate into the ground, but instead flows to a body of water


water that gets absorbed into the soil and travels down to the aquifer


liquid water that gets heated up and becomes water vapor


when water vapor comes together to become clouds


water that travels through plants and evaporates out of their leaves

surface water

water that's on the surface; rivers, lakes, ocean


rock formation under the ground that stores water


a man-made lake created when a dam is put on a river


an algal bloom; created when nitrogen and phosphorus are added to the water


a small aquatic organism that is large enough to see without a microscope and doesn't have a backbone


when salt is taken out of saltwater to create freshwater

indicator species

organisms that tell you about the health of the ecosystem


water that comes from sinks, toilets, showers, storm drains


the solids that sink to the bottom during wastewater treatment

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