Q1Written answer
Name an organism found as a secondary carnivore in an aquatic ecosystem.
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Ans: Shark
NCERT Exemplar · Class 12 · Biology
Chapter 14: Ecosystem
Practice each question, then open the answer or worked solution.
Very Short Answer Questions
19 questionsQ2Written answer
What does the base tier of the ecological pyramid represent?
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Ans: Producers
Q3Written answer
Under what conditions would a particular stage in the process of succession revert back to an earlier stage?
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Ans: A particular stage in the succession process would revert to an earlier stage in the event of natural or human-induced disruptions.
Q4Written answer
Arrange the following as observed in vertical stratification of a forest:
Grass, Shrubby plants, Teak, Amaranths.
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Ans: Teak → Amaranths → Shrubby plants → Grass
Q5Written answer
Name an omnivore which occurs in both the grazing food chain and the decomposer food chain.
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Ans: Crow
Q6Written answer
Justify the pitcher plant as a producer.
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Ans: Photosynthesis is carried out by the pitcher plant, which contains chlorophyll. It solely eats insects to get nitrogen from them. As a result, the pitcher plant is a producer.
Q7Written answer
Name any two organisms which can occupy more than one trophic level in an ecosystem.
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Ans: Sparrow: When it feeds on grans, it is a primary consumer, but when it eats worms and insects, it becomes a secondary consumer.
Human: When it eats grains and pulses, it is a primary consumer, however when it eats lamb, it is a secondary consumer.
Q8Written answer
In the North East region of India, during the process of jhum cultivation, forests are cleared by burning and left for regrowth after a year of cultivation. How would you explain the regrowth of forests in ecological terms?
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Ans: Forest regeneration is an example of ecological succession in this circumstance. After forest clearing, the conditions become xerarch, which then progresses to mesarch as the forest grows.
Q9Written answer
Climax stage is achieved quickly in secondary succession as compared to primary succession. Why?
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Ans: After primary succession, soil becomes available. It creates perfect conditions for the growth of larger plants. When compared to primary succession, secondary succession occurs more swiftly. Hence, climax is furthermore reached more rapidly.
Q10Written answer
Among bryophytes, lichens and fern, which one is a pioneer species in a xeric succession?
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Ans: Lichens