Pesticides and Pest Control

The amplification of a toxic compound which is resistant to elimination from the body and accumulates with each trophic level is known as Bioaccumulation/Biomagnification.

Snake is likely to show highest concentration of DDT once it has been introduced into the ecosystem.

The accumulation of persistent chemicals like DDT in higher trophic levels is the definition of biomagnification. It is a major environmental concern for apex predators.

Biomagnification refers to increase in concentration of the toxicant at successive trophic levels. This happens because a toxic substance accumulated by an organism cannot be metabolised or excreted, and is thus passed on to the next higher trophic level. Thus, the correct answer is option A.

Biomagnification is the accumulation or increasing concentration of lipophilic pesticides in the top members of the food chain. During biomagnification, the concentration of non-degradable pesticide like DDT goes on increasing along the food chain and highest values occur in the consumers of the top trophic level. So, the value of pesticide will go on increasing at each trophic level. 

Biomagnification is process of transfer of toxic substance such as DDT and Mercury, in increasing concentration in successive trophic level of food chain.
Pollutant increases in concentration from Producers → Primary consumers → Secondary consumers →Tertiary consumers → Top consumer. 

Slow metabolism and excretion of pesticides cause their accumulation in fat tissues of organisms (biomagnifications), particularly affecting the top consumers (carnivores) causing the decrease in their population size. Pesticides in water (through agricultural runoff) concentrate in fishes and then in Osprey (Ospreys feed on fishes). Biological Magnification is an accumulation of substances over subsequent trophic levels in the food chain. Thus, the correct answer is option A.

A few toxic substances, often present in industrial wastes, can undergo biological magnification (biomagnification) in the food chain. 

DDT is an organochlorinated compound that was used as an insecticide. It is highly stable and is not degradable. It tends to stay in the adipose tissue of the living organisms. Due to this property, it enters the food chain and is accumulated at each trophic level. As the primary consumers eat more producers and similarly, secondary consumers eat more primary consumers, the organisms at the higher trophic levels will have an increased concentration of DDT. This process is called d the boimagnification.

Persistent pesticides are stable in chemical nature and tend to solubilize in the fats of the living organisms, these show persistence in the food chain. It is seen that the level of persistent pesticides increases as the food chain progresses. It means, the primary consumers will have more persistent pesticides concentration than the producers, the secondary consumers will have more than primary consumers and so on. The highest concentrations will be seen in the top carnivore. This is because the consumers at the successive trophic level consume more than the previous level to fulfil the energy requirements. Due to this, persistent pesticides keep on accumulating in the successive trophic levels in higher concentrations. This process is called the biomagnification.

Biological magnification is the process of increasing concentration of the toxic substances in the living organism as they go up the food chain.

Biomagnification is the process where the concentration of toxic compounds increases in the body of the organisms through the food chain. The organisms at the higher trophic level will have more concentration of the compounds. Here, fishes are at the highest trophic level, so they will accumulate maximum amount of pesticides. So, the correct answer is 'Fishes'.