Question

what term is used to describe an increased concentration of toxic chemicals as we move up the food chain? biodegrading biomagnification

Explanation:

To solve this, we analyze the definitions:

• Biodegrading: Breakdown of substances by organisms. Doesn't relate to toxin concentration increase in food chain.
• Biomagnification: Process where toxic chemicals' concentration increases as we move up the food chain (organisms at higher trophic levels accumulate more toxins from prey). This matches the question's description.

Answer:

The correct option is: biomagnification (the term describing increased toxic chemical concentration up the food chain). The other option, biodegrading, refers to breakdown of substances, not concentration increase in a food chain.