In a food chain, green plants are called
- A.Producers
- B.Primary consumers
- C.Decomposers
- D.Secondary consumers
Correct answer
Explanation
The correct answer is A, producers. Green plants make their own food from carbon dioxide and water by photosynthesis, using the energy of sunlight, so they are also called autotrophs. They form the first trophic level, and all other organisms in the ecosystem depend directly or indirectly on the food they prepare.
Option B, primary consumers, are the herbivores that feed on plants, such as the grasshopper, the deer and the cow. Option C, decomposers, are bacteria and fungi, which break down dead bodies and waste and return the nutrients to the soil. Option D, secondary consumers, are the carnivores that eat herbivores, such as the frog in the chain grass, grasshopper, frog, snake, hawk. Fix the order of that chain in your mind, since questions often ask for the level of one organism in it.
Read the full article: Ecosystem and Food Chains: Components, Levels and Pyramids
Practice Questions
View allThe term ecosystem was coined by which scientist?
- A.A. G. Tansley
- B.Charles Darwin
- C.Raymond Lindeman
- D.Charles Elton
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The British botanist Arthur George Tansley used the word ecosystem in 1935 for a unit in which living organisms and their non-living surroundings are treated together as one system exchanging energy and matter.
Read the full explanation →The ten per cent law of energy transfer in a food chain was given by
- A.A. G. Tansley
- B.Raymond Lindeman
- C.Odum
- D.Ernst Haeckel
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It says that only about ten per cent of the energy present at one trophic level is passed on to the next, since the rest is used in respiration and other life processes and is lost to the surroundings as heat.
Read the full explanation →Which of the following ecological pyramids is always upright?
- A.Pyramid of numbers
- B.Pyramid of biomass
- C.Pyramid of energy
- D.All three are always upright
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Energy is lost as heat at every transfer from one trophic level to the next, so a higher level can never hold more energy than the level below it.
Read the full explanation →Bacteria and fungi that break down dead plants and animals are known as
- A.Producers
- B.Decomposers
- C.Herbivores
- D.Omnivores
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They feed on dead bodies, fallen leaves and waste matter, break the complex organic substances into simple ones and release nutrients back into the soil, water and air, where plants can take them up again.
Read the full explanation →The flow of energy in an ecosystem is
- A.unidirectional
- B.cyclic, like the flow of nutrients
- C.from consumers to producers
- D.unchanged at every trophic level
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Energy enters an ecosystem as sunlight, is fixed by green plants, and then moves from producers to herbivores, to carnivores and finally to decomposers.
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