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प्रश्न
What are planktons?
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उत्तर
The tiny herbivorous plants and animals present in water are known as plankton. Plankton are classified as phytoplankton (plants) and zooplankton (animals).
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संबंधित प्रश्न
State with reason any two possible consequences of elimination of decomposers from the Earth.
What will happen if we kill all the organisms in one trophic level?
In the following food chain, 20,000 J of energy was available to the plants. How much energy would be available to man in this chain?
Plants → Sheep → Man
What is the difference between the food habits of organisms belonging to the first and the third trophic levels? Give one example each of the organisms belonging to these two trophic levels.
Which of the following group of organisms are not constituents of a food chain?
- grass, lion, rabbit, wolf
- plankton, man, fish, grasshopper
- wolf, grass, snake, tiger
- frog, snake, eagle, grass, grasshopper
In the food chain comprising of a snake, grass, insect, and frog, the secondary consumer is :
(a) insect
(b) snake
(c) frog
(d) grass
The sea water contains water beetles, tadpole, fish and weeds.
Which organisms are (i) predators, and (ii) prey?
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 rabbits and grass plants if the number of foxes decreased?
Fill in the following blank with suitable word :
Plants → Antelope → ............
Will the levels of biological magnification be different at different levels of the ecosystem?
In the food chain given below, if the amount of energy available at fourth trophic level is 5 kJ, what was the energy available at the producer level?
Grass → Grasshopper → Frog → Snake → Hawk
(a) 500 kJ
(b) 50 kJ
(c) 5000 kJ
(d) 5 kJ
Most of the water surface of a lake is covered with algae. This algae is part of the food chain which also includes small fish, bird, larvae and big fish. Which of the following will obtain the maximum energy?
(a) big fish
(b) bird
(c) larvae
(d) small fish
A food chain comprising birds, green plants, fish and man. The concentration of harmful chemical entering the food chain will be maximum in ______.
Which of the following is an autotroph?
Food chains are very important for the survival of most species.
Matter and energy are two fundamental inputs of an ecosystem. Movement of:
In a food chain, the third trophic level is always occupied by
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.
In the following food chain, only 2J of energy was available to the peacocks. How much energy would have been present in Grass? Justify your answer.
GRASS → GRASS HOPPER → FROG → SNAKE → PEACOCK
