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प्रश्न
'If we excessively use pesticides to protect the crops from diseases, then it may cause long-term damage to mankind'. Justify this statement.
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उत्तर
Chemical substances such as pesticides are sprayed over crop plants to protect them from pests and diseases. When herbivorous animals eat the plant food, these poisonous chemical pesticides go into their bodies. Man, being an omnivore, eats plant food as well as the meat of herbivores. Thus, the pesticides present in plant food and herbivores get transferred to man's body through food. Pesticides are non-biodegradable chemicals, so they get accumulated at each trophic level. Since humans occupy the top level in any food chain, the maximum amount of harmful chemical pesticides gets accumulated in our bodies, damaging our health gradually.
Hence the statement 'excessive use of pesticides to protect crops from diseases may cause long-term damage to mankind' is justified.
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संबंधित प्रश्न
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(a) Write a food chain comprising all the four organisms mentioned above.
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(c) Name the link which is a predator as well as a prey.
(d) Name (i) second trophic level, and (ii) third trophic level.
(e) Which link of this food chain can feed on second trophic level as well as third trophic level, independently?
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