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Ecosystems — BIOLOGY STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 ScienceBIOLOGYEcosystems3 Marks
Question
Apart from plants and animals, microbes form a permanent biotic component in an ecosystem. While plants have been referred to as autotrophs and animals as heterotrophs, what are microbes referred to as? How do the microbes fulfil their energy requirements?
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Answer

Productivity, decomposition, energy flow and nutrient cycling are integral features of any ecosystem. Plants and animals play important roles in productivity. While some microbes play the role in productivity; as some of them microbes are autotrophs, e.g. some algae and some chemosynthetic bacteria. Most of the microbes are heterotrophs. Parasitic microbes get nutrition from the host on which they depend. Many microbes are saprotrophs. They get nutrition from detritus, i.e. they are important part of detritus food chain.

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