Detritus is
1. Dead raw material for decomposition.
2. Partially decomposed organic matter.
3. Dead remains of animals & plants.
4. Both 1 and 3
In most ecosystems, all the pyramids of number, energy and biomass are upright. It indicates that
(a) Producers are more in number and biomass than the herbivores.
(b) Herbivores are less in number and biomass than the carnivores.
(c) Energy at a lower tropic level is always more than at a higher level.
Choose the correct option.
1. Only (a) is correct.
2. Only (b) is correct.
3. Both (a) and (c) are correct.
4. Both (b) and (c) are correct.
Assertion (A): | We generally undervalue the magnitude of ecosystem services that benefits us. |
Reason (R): | We do not attach a monetary value to the services of natural ecosystems. |
1. | Both (A) and (R) are true and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are true but (R) is not the correct explanation of (A). |
3. | (A) is true but (R) is false. |
4. | Both (A) and (R) are false. |
Addition of which of the following can prevent leaching of minerals?
1. humus
2. mycorrhizae
3. rhizobia
4. calcium
Given below is a hypothetical pyramid of energy. The amount of energy left at the level of secondary consumers would approximately be:
1. | 10000 J | 2. | 1000 J |
3. | 100 J | 4. | 50 J |
What type of ecological pyramid would be obtained with the following data?
Secondary consumer: 120 g
Primary consumer: 60 g
Primary producer: 10 g
1. Inverted pyramid of biomass
2. Pyramid of energy
3. Upright pyramid of numbers
4. Upright pyramid of biomass
The primary producers of the deep-sea hydrothermal vent ecosystem are:
1. green algae
2. chemosynthetic bacteria
3. blue-green algae
4. coral reefs
Presence of plants arranged into well-defined vertical layers depending on their height can be seen best in:
1. Tropical Rain Forest
2. Grassland
3. Temperate Forest
4. Tropical Savannah
1. | A.G. Tansley | 2. | E. Haeckel |
3. | E. warming | 4. | E.P. Odum |
In which of the following, do both pairs have the correct combination?
1. | Gaseous nutrient cycle Sedimentary nutrient cycle |
Carbon and nitrogen Sulphur and phosphorous |
2. | Gaseous nutrient cycle Sedimentary nutrient cycle |
Carbon and sulphur Nitrogen and phosphorus |
3. | Gaseous nutrient cycle Sedimentary nutrient cycle |
Nitrogen and sulphur Carbon and phosphorous |
4. | Gaseous nutrient cycle Sedimentary nutrient cycle |
Sulphur and phosphorous Carbon and nitrogen |