Biomagnification is the phenomena in which toxic chemicals released from industrial and agricultural wastes flow into water bodies and contaminate them. These toxic chemicals causes diseases, genetic mutations, birth defects and death in organisms which indirectly or directly take them. These toxic chemicals enters into the food chain and affects mainly the organisms which are at higher trophic levels. They get settle at the bottom of the water body with sediments and organisms feed on these sediments. These toxic chemicals are not digested therefore they are transferred from one trophic level to higher trophic level in an undigested and unchanged form. In the highest trophic level the concentration of these toxic chemicals becomes highest and result in mortality of organisms. This shows magnifying and enlarged destruction of organisms in a food chain hence named biomagnification. It affects endangered species of predators like fishes, aquatic mammals and birds which eat fishes.
Biomagnification can be defined as the gradual increase in the concentration of the toxic chemicals at each trophic level. Lowest at the producers and highest at the higher trophic level.
The toxic chemicals such as industrial waste, radioactive waste that enters in the food chain and starts effecting the health of the plants and animals and its concentration increases at each trophic level.
The toxic chemicals gets transferred from the producers to consumers (predators except the primary consumers) and during this transfer the concentration increases.
<span>The correct answer is 'secondary consumer’. This is because the yellowfin tuna eats herbivorous fish (these are primary consumers - they only eat plants, which are producers) and take refuge from predators. This shows they are not tertiary consumers, as tertiary consumers are at the top of the food chain.</span>
