Stratification of an ecosystem means:
1. | Vertical distribution of different species occupying different levels |
2. | Vertical distribution of different species occupying the same levels |
3. | Horizontal distribution of different species occupying different levels |
4. | Horizontal distribution of different species occupying the same levels |
The rate of formation of new organic matter by consumers in an ecosystem is known as:
1. | Gross Primary productivity |
2. | Net Primary productivity |
3. | Secondary productivity |
4. | Non-productivity |
Organisms that are capable of conversion of inorganic material into organic material with the help of the radiant energy of the sun include:
I: | Plants |
II: | Photosynthetic bacteria |
III: | Chemosynthetic bacteria |
1. | I only | 2. | I and II only |
3. | I and III only | 4. | I, II, and III |
The nutrients in an ecosystem are:
1. | continuously lost from an ecosystem |
2. | needed as a continuous supply from the outside |
3. | recycled time and again indefinitely |
4. | continuously synthesized by physical forces |
The earth is regarded as “open” system with respect to:
1. | organisms | 2. | chemicals |
3. | energy | 4. | water |
If decomposers go extinct on Earth:
1. | Detritivores will replace them |
2. | Primary production will increase |
3. | Nutrients will accumulate in dead plants and animals |
4. | There will be no effect on carnivores |
What is the best description of trophic efficiency?
1. | the ratio of net secondary production to the assimilation of primary production. |
2. | the percentage of production transferred from one trophic level to the next. |
3. | a measure of how nutrients are cycled from one trophic level to the next. |
4. | usually greater than production efficiencies. |
What percent of the energy fixed by primary producers in a typical field ecosystem is received by a secondary consumer?
1. | 0.1% | 2. | 1% |
3. | 10% | 4. | 20% |
The residual, after autotrophic respiration is subtracted from GPP, is:
1. | secondary productivity | 2. | net primary productivity |
3. | standing crop biomass | 4. | chemosynthesis |
The producers in aquatic ecosystems include all except:
1. | cyanobacteria | 2. | algae |
3. | plants | 4. | zooplankton |