Final answer:
Biomagnification is the term used to describe the increased concentration of toxic chemicals as we move up the food chain.
Step-by-step explanation:
The term used to describe this increased concentration of toxic chemicals as we move up the food chain is biomagnification. Biomagnification occurs when organisms at higher trophic levels consume prey that contains toxins, resulting in the accumulation of toxins in their bodies. As a result, the concentration of toxic chemicals increases as we move up the food chain.
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