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प्रश्न
Explain why, a food chain usually cannot have more than three or four steps.
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उत्तर
At each trophic level in a food chain, a large portion of the energy available is utilised for the maintenance of organisms in that trophic level and is lost as heat. Food chains usually cannot have more than three or four steps because the energy available for organisms in any additional step will be so small that it will be insufficient to sustain the life of those organisms.
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संबंधित प्रश्न
Which of the following are always at the second tropic level of food chains?
Which of the following constitute a food-chain?
Name the organisms belonging to the second and the fourth trophic levels in the food chain comprising the following :
Frogs, Plants, Snakes, Hawk, Insects
What are the various steps of food chain called?
Write down a food chain which ends with humans.
At which trophic level a person is feeding when he is eating apple.
Write a common food chain of a pond ecosystem having four links.
What is a food chain?
In a food chain, the third trophic level is always occupied by :
(a) carnivores
(b) herbivores
(c) decomposers
(d) producers
Which of the following is not a producer?
(a) grass
(b) zooplankton
(c) phytoplankton
(d) paddy
A food chain occurring in the sea which provides food for many people can be written as :
phytoplankton → zooplankton → X → Y
Name two zooplanktons.
What would happen to the number of grass plants and foxes if the number of rabbits increased?
If a harmful chemical enters a food chain comprising cat, mice and plants, which one of these organisms is likely to have the maximum concentration of the harmful chemical in its body?
A forest ecosystem having a lot of green plants has some foxes, lions and rabbits in it.
(a) Write a food chain comprising all the four organisms mentioned above.
(b) Name (i) one herbivore, and (ii) two carnivores, in this food chain.
(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?
(f) If the sun provides 1000 J of energy to the plants, then how much energy will be transferred to fox through the food chain.
What are decomposers? What will be the consequence if the decomposers are completely eradicated from an ecosystem? Give justification in support of your answer.
Give one example of a food chain in an aquatic ecosystem?
What would happen if an organism is removed from the food chain?
The food chain begins with the energy given by the ______.
Animals that eat both plants and animals are called as Carnivores.
DDT was sprayed in a lake to regulate breeding of mosquitoes. How would it affect the trophic levels in the following food chain associated with a lake? Justify your answer.
