Science (086) — AI-generated practice question

Pathway: The pesticide sprayed on the paddy field is washed into the pond. Microscopic organisms (phytoplankton/zooplankton) absorb it → small fish eat these organisms → large fish eat small fish → humans in the village eat the fish, thus consuming the pesticide.

Phenomenon: This is called biological magnification (biomagnification) — the progressive increase in concentration of non-degradable substances at each successive trophic level.

Why humans are more affected: Paddy plants are at the first trophic level, so they accumulate the least amount of pesticide. Humans are at the highest trophic level; the pesticide concentration multiplies at each level, so humans receive the maximum accumulated dose.

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• Examiners expect you to clearly trace the food chain (water → plankton → small fish → large fish → human).
• Name the phenomenon correctly: biological magnification.
• The key contrast is trophic level position: plants (T1) accumulate least; humans (T5) accumulate most. This directly answers "why humans more affected."
• This concept is from Ch. 15 (Our Environment) — Exercise Q6 asks exactly this.