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Ecosystem

Short Answer Type

41.

Sketch the following pyramids.
(i) Pyramid of number (ii) Pyramid of biomass. (iii) Pyramid of energy.

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42.

Construct a pyramid of biomass, starting with phytoplankton. Label three trophic levels. Is the pyramid upright or inverted? Why?

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43. Why is the pyramid of energy always upright ?

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Long Answer Type

44.
Define ecological pyramids and describe with examples, pyramids of number and biomass.

Ecological pyramids are diagrams or pictorial representation that illustrate how ecologically important factors, such as energy, biomass, and population size, vary between trophic levels in an ecosystem.
Pyramids of number represents the number of organisms at each trophic level. For example in the grassland ecosystem the number of plants is the highest followed by number of primary consumer that is mice. Followed by Snake and eagle .

Pyramid of biomass represents the amount of biomass produced at each trophic level. For example in aquatic ecosystem the biomass of phytoplankton or the producer is the minimum while the number of primary consumer that is zooplankton is more . The number of the tertiary consumer or fishes in this case is the highest.