Final answer:
Biomagnification is the process in which low levels of a chemical in a lower trophic level of a food chain become increasingly concentrated as you move up to higher trophic levels.
Step-by-step explanation:
Low levels of an organic chemical from a plastic factory found in a river and increasing concentrations in organisms as you move up the food chain is an example of Biomagnification. Biomagnification occurs when a pollutant or toxin becomes more concentrated at higher levels of a food chain, resulting in potentially harmful levels of the chemical in top predators.
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