Question

If a harmful chemical enters a food chain comprising cat, mice and plants, which one of these organisms is likely to have the maximum concentration of the harmful chemical in its body?​ ​

Answer 1

Arranging the organisms in a food chain, we get,
Plants → Mice → Cat​ ​
The concentration of harmful chemicals increases with increase in the trophic level. The accumulation of harmful chemicals such as pesticides in the living organisms, through the food chain is called biomagnification.​ ​

Hence, the concentration of harmful chemicals will be maximum in the cat, which is the highest trophic level in the given food chain.​