Question

Concentration of harmful chemical up to the trophic level is termed as

Answer 1

Biomagnification.

Birds will have maximum concentration of chemical in its body. It's a simple process of Biomagnification. Can be explained in this case as follows.

If plankton have 0.01% mercury then the fish will eat many plankton and this leads to accumulation of mercury in fish body. Same way if bird eat 2 or 3 fishes it will led to more accumulation or magnification of mercury in its body.

i hope it help you.

Answer 2

BIOLOGICAL MAGNIFICATION