Based on the source of organism’s nutrition or food, they occupy a specific place in the food chain that is known as-
1. Strata
2. Trophic level
3. Sere
4. Chain level
What do you mean by the standing crop?
1. Crop in a field at a given time
2. Each trophic level has a certain mass of living material at a particular time.
3. Each trophic level has a certain mass of organic material at a particular time.
4. Top trophic level has a certain mass of organic material at a particular time.
The standing crop is measured as the-
1. Mass of living organisms in a unit area.
2. The number of living organisms in a unit area.
3. Calculated from the net primary productivity
4. Both 1 and 2.
Why does the number of trophic levels in the grazing food chain is restricted ?
1. As the transfer of energy follows 10 per cent law
2. So that food chain remains short
3. As there are few species the community
4. So that transfer of energy could be more efficient.
What does 10 per cent law say?
1. | Less than 10 per cent of the energy is transferred to each trophic level from the lower trophic level |
2. | Only 10 per cent of the energy is transferred to each trophic level from the lower trophic level |
3. | Only 10 per cent of the energy is assimilated from the eaten food |
4. | Consumer gains 10 per cent mass of the consumed food |
The base of each pyramid represents the _________or the ___________level while the apex represents ____________
1. Consumers, first trophic and top trophic level
2. Producers, first trophic and top trophic level
3. Producers, second trophic and top trophic level
4. Consumers, second trophic and top trophic level
Identify the relationship represented by the pyramid
1. Pyramid of number
2. Pyramid of biomass
3. Pyramid of energy
4. None of the above
Which of the following pyramid represents the pyramid of number in grassland?
A
B
C
1. A
2. B
3. C
4. B & C
Which of the following statement is incorrect?
1. | Only three top-carnivores are supported in an ecosystem based on production of nearly 6 million plants. |
2. | Pyramid of biomass shows a sharp increase in biomass at higher trophic levels. |
3. | Pyramid of biomass is inverted if small standing crop of phytoplankton supports large standing crop of zooplankton. |
4. | Pyramid of energy is always upright. |
If the available energy at first trophic level is 10000 J then how much trophic levels it could support further?
1. 2
2. 3
3. 4
4. 5