Science
(i) Construct a food chain of four trophic levels comprising the following :
Hawk, snake, plants, rat.
(ii) 20,000 J of energy was transferred by the producers to the organism of second trophic level. Calculate the amount of energy that will be transferred by organisms of the third trophic level to the organisms of the fourth trophic level.
Answer
(i) Plants → Rat → Snake → Hawk
(ii) According to the 10% rule of energy transfer, 10% of energy is transferred to next trophic level. Amount of energy available to second trophic level = 20,000 J Therefore, amount of energy transferred to third trophic level = 10% of 20,000 J = 2000 J. And, amount of energy transferred to fourth trophic level = 10% of 2000 J = 200 J
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