In general, the biomass in an ecosystem will be greatest at the trophic level comprising.
1. secondary consumers
2. primary consumers
3. producers
4. tertiary consumers
Consider the following two statements:
l. | The annual net primary productivity of the whole biosphere is approximately 170 billion tons (dry weight) of organic matter. |
ll. | Majority of this is contributed by the oceans as they occupy larger area of earth. |
1. Both l and ll are correct and ll explains l
2. Both l and ll are correct but ll does not explain l
3. l is correct but ll is incorrect
4. l is incorrect but ll is correct
What percent of energy in the sunlight availble to the primary producers is converted by them into net primary productivity ?
1. 1
2. 2
3. 5
4. 10
Both hydrach and xerarch successions:
1. Take same time
2. Have similar sere
3. Lead to mesic conditions
4. Have same pioneer species
The second trophic level in a lake is:
1. Phytoplankton
2. Zooplankton
3. Benthos
4. Fishes
The rate of formation of new organic matter by consumers is called as:
1. Secondary productivity
2. Standing crop
3. Standing state
4. Net primary productivity
The limitations of ecological pyramids include all the following except:
1. The do not take into account the same species belonging to two or more trophic levels
2. They do not represent relationships between organisms at different trophic levels
3. They assume a simple food chain and do not consider food webs
4. Saprotrophs are not given any place in the ecological pyramids
About what percent of the global carbon is contained in the atmosphere?
1. 71
2. 49
3. 17
4. about 1
Which of the following organisms will be the first to colonize a bare rock?
1. Annual plants
2. Lichens
3. Perennail plants
4. Herbs and shrubs
Most food chains are composed of
1. 1 or 2 species
2. 3 or 4 species
3. 9 or 10 species
4. More than 16 species