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the aggregate of small plant and animal organisms that float or drift in great numbers in fresh or salt water


all organisms that swim actively in open water, independent of currents


organisms (plants and animals) that live at or near the bottom of a sea

food web

network of complex interactions formed by the feeding relationships among the various organisms in an ecosystem

intertidal zone

part of the shoreline that is underwater at high tide and exposed to the air at low tide


the tidal arm of a river


the science of cultervating marine fish.


small like pertrusion


a device that bounces sound waves off underwater objects and then records the echoes of these sound waves

continental shelf

a gently sloping, shallow area of the ocean floor that extends outward from the edge of a continent

continential slope

a steep slope from the continential shelf to the ocean floor


process of removing salt from salt water

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