Correctly depict (also indicate the trophic level) and describe the ecological pyramid of biomass in sea with 40 standing crop of phytoplankton supporting 90 standing crop of zooplankton which further supports 120 small fishes.
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Solution and Explanation
To solve this problem, we need to illustrate the ecological pyramid of biomass in the sea and describe its components, showing the trophic levels and how the different organisms are related.
1. Understanding the Ecological Pyramid of Biomass:
An ecological pyramid of biomass shows the amount of living material (biomass) present in different trophic levels of an ecosystem. In marine ecosystems, it is usually represented as a pyramid with the base having the producers (phytoplankton), followed by the consumers at higher trophic levels (zooplankton, small fishes, etc.).
2. Trophic Levels:
- Trophic Level 1: Producers – Phytoplankton, which are the primary producers, form the base of the pyramid.
- Trophic Level 2: Primary Consumers – Zooplankton that feed on phytoplankton.
- Trophic Level 3: Secondary Consumers – Small fishes that feed on zooplankton.
3. Given Values:
Standing Crop of Phytoplankton: 40 units
Standing Crop of Zooplankton: 90 units
Standing Crop of Small Fishes: 120 units
4. Calculating and Depicting the Ecological Pyramid:
We can create the ecological pyramid of biomass based on the given standing crops. The pyramid has the following shape:
- Phytoplankton (Trophic Level 1): 40 units of biomass.
- Zooplankton (Trophic Level 2): 90 units of biomass.
- Small Fishes (Trophic Level 3): 120 units of biomass.
From the data, we can observe that the biomass increases as we move up the pyramid, which is contrary to the general shape of an ecological pyramid where the biomass typically decreases with higher trophic levels. However, this could occur in specific cases where the organisms at higher trophic levels are more efficient in converting biomass into their own bodies.
5. Final Answer:
The ecological pyramid in the sea would look as follows:
- Trophic Level 1 (Phytoplankton): 40 units
- Trophic Level 2 (Zooplankton): 90 units
- Trophic Level 3 (Small Fishes): 120 units
This representation is an example where the biomass does not decrease as we move from lower to higher trophic levels, which is unusual but can occur in certain ecosystems, such as in marine environments with highly efficient energy transfer.
Top Questions on Ecology and Environment
Highly conserved proteins such as Haemoglobin and Cytochrome-C provide the best biochemical evidence to trace evolutionary relationships between different groups. Cytochrome-C is formed of 104 amino acids. Cytochrome-C is the respiratory pigment present in all eukaryotic cells. It has evolved at a constant rate during evolution. In chimpanzees and humans, Cytochrome-C genes are identical. The given data shows the evolution of the Cytochrome-C gene in different mammals from kangaroos, cows, rodents to humans:
Groups Nucleotide substitution in the gene of Cytochrome-C Millions of years ago Human/Kangaroo 100 125 mya Human/Cow 75 120 mya Human/Rodent 60 75 mya (a) Select the correct option for the time of separation of two groups and the number of nucleotide substitutions in the gene of Cytochrome-C:
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(i) Human and Kangaroo
(ii) Human and Rodent
(c)
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OR
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