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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.
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
Name one decomposer.
In a food chain, the third trophic level is always occupied by :
(a) carnivores
(b) herbivores
(c) decomposers
(d) producers
In the figure given alongside, the various trophic levels are shown in the form of a pyramid. At which trophic level the maximum energy is available?
Give one example of a food chain having four organisms. Below each organism write the three appropriate terms from the part (a) above which you think it represents.
If 5 joules of energy is available at producer level (plants), then how much energy will be transferred to the lion in the following food chain?
Plants → Goat → Lion
Explain why, the flow of energy in the ecosystem is said to be unidirectional.
Which of the following limits the number of trophic levels in a food chain?
(a) insufficient food supply from producer level
(b) decrease in energy at higher trophic levels
(c) increase in the number of organisms at higher trophic levels
(d) accumulation of harmful chemicals at higher trophic levels
An aquatic food chain comprises of the organisms like tadpoles, weeds, fish and water beetles. The organism which gets the minimum energy through this food chain is :
(a) water beetles
(b) tadpoles
(c) weeds
(d) fish
Differentiate between herbivores and carnivores.
In a food chain, the third trophic level is always occupied by
