A food chain consists of fish, larvae, phytoplankton and birds. The level of pesticides in water in which the fish, larvae and phytoplankton live is quite high.

(a) In which organisms the pesticides enter from the polluted water? What is this level of organisms known as?


(b) Which organism will have the maximum amount of pesticides accumulated through the food chain? What is this process known as?


(c) Write the food chain comprising all the organisms mentioned above.


(d) Which other organism you could write in place of bird in the above food chain?

a) Pesticides enter the Phytoplankton from the polluted water. This level of organism is known as producers. They produce their own food through the process of photosynthesis.


b) Birds will have the maximum amount of pesticides accumulated through the food chain because they are at the top in the food chain.


The process of accumulation of substances like pesticides where they move up the food chain, enter the aquatic organisms which are in turn are eaten by birds or humans is known as biological magnification.


c) Food chain= Phytoplankton-Larvae-Fish-Birds.


d) Human being can be considered in place of birds in the above food chain since they are omnivore too like certain birds; they eat food both of plant and animal origin.


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