Q11Written answer
What is the ultimate source of energy for the ecosystems?
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Ans: Sun
NCERT Exemplar · Class 12 · Biology
Chapter 14: Ecosystem
Practice each question, then open the answer or worked solution.
Very Short Answer Questions
19 questionsQ12Written answer
Is the common edible mushroom an autotroph or a heterotroph?
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Ans: Heterotroph
Q13Written answer
Why are oceans least productive?
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Ans: Solar radiation is scarce in the oceans, particularly in the deep waters. Because of the same reason, oceans are the least productive.
Q14Written answer
Why is the rate of assimilation of energy at the herbivore level called secondary productivity?
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Ans: Secondary productivity refers to the rate at which consumers create new organic matter. Consumers obtain raw resources from producers for this reason, which is facilitated via assimilation. Because of the same reason, the rate of energy assimilation at the herbivore level is referred to as secondary productivity.
Q15Written answer
Why are nutrient cycles in nature called biogeochemical cycles?
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Ans: Nutrients are cycled through both biotic and abiotic components. The term 'bio' refers to biotic elements, whereas 'geo' refers to abiotic elements.
As a result, biogeochemical cycles are used to describe nutrient cycles in nature.
Q16Written answer
Give any two examples of xerarch succession.
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Ans: The two examples of xerarch succession are bare rock and sand.
Q17Written answer
Define self-sustainability.
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Ans: A self-sustainable system is one that is self-sustaining and does not require any external input. The system's ability to sustain itself is known as self-sustainability. Natural Ecosystems are self-sustaining.
Q18Written answer
Given below is a figure of an ecosystem. Answer the following questions.
i. What type of ecosystem is shown in the figure.
ii. Name any plant that is characteristic of such an ecosystem.
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Ans: Desert ecosystem
Ans: Bushes, acacia, etc.
Q19Written answer
What is common to earthworm, mushroom, soil mites and dung beetle in an ecosystem.
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Ans: They are all referred to as detritivores since they are the major consumers in a detritus food chain.