Final answer:
Biomagnification is the term used to describe an increased concentration of toxic chemicals as we move up the food chain.
Step-by-step explanation:
The term used to describe an increased concentration of toxic chemicals as we move up the food chain is biomagnification. Biomagnification refers to the process where the concentration of harmful substances, such as pesticides or heavy metals, increases as they pass from one trophic level to the next.
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