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Bioaccumulation. refers to the accumulation of substances, such as pesticides, or other organic chemicals in an organism. occurs when an organism absorbs a toxic substance at a rate greater than that at which the substance is metabolized (broken down) or excreted (lost).
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Bioaccumulation refers to the accumulation of substances, such as pesticides, or other organic chemicals in an organism. occurs when an organism absorbs a toxic substance at a rate greater than that at which the substance is metabolized (broken down) or excreted (lost).
Biological Magnification Magnify means “to increase”. Biological magnification is the process by which a pollutant becomes more concentrated in the bodies of organisms at higher and higher trophic levels. Link Biomagnification Video: Teacher Tube
Biological Magnification DDT Click on Picture Below …Or Click this Picture for Sound Only
If you were to illustrate the biomagnification of poisons using a pyramid, what would it look like?
DDT was once widely used in the United States because it was effective in killing insects, mainly by affecting insect nervous systems. Chemicals may affect different kinds of animals differently,and chemicals may change in form as theymove through a food chain. In fish-eating birds, though, thechemical DDT affects the formation of eggshells, whichwas not foreseen by those who spread the chemical.
Biological Magnification Heavy Metals • Lead • Mercury • Cadmium
Bioaccumulation varies between individual organisms as well as between species. Large, fat, long-lived individuals or species with low rates of metabolism or excretion of a chemical will bioaccumulate more than small, thin, short-lived organisms. Thus, an old lake trout may bioaccumulate much more than a young bluegill in the same lake.
…Other Chemicals Agent Orange: Herbicide - Used to kill trees in Cambodia during the Vietnam War. Caused cancers in soldiers. PCBs : Chemicals in electrical transformers, etc. Causes cancer in high concentrations.
Biomagnification of Mercury Interactive by Oceanus Click Here Biomagnification Tutorial with Questions Click Here BiomagnificationPCBs Tutorial with Questions Click Here
A Graduate Student’ Research on Biomagnification Click Here