Consider the following statements:
The rate of decomposition is high if:
I: | The detritus is rich in lignin and chitin. |
II: | The detritus is rich in nitrogen and sugars. |
III: | The environmental conditions are warm and moist. |
Which of the above statements are true?
1. | I and II only | 2. | I and III only |
3. | II and III only | 4. | I, II, and III |
Consider the following statements:
I: | Trophic level in an ecosystem represents a functional level, not a species as such. |
II: | Saprophytes are accorded the position of a top consumer in an ecosystem. |
III: | A species can occupy more than one trophic level in the same ecosystem at the same time. |
Which of the above statements are true?
1. | I and II only | 2. | I and III only |
3. | II and III only | 4. | I, II, and III |
Consider the following statements:
I: | The atmosphere only contains about 1% of total global carbon. |
II: | Unlike the carbon cycle, there is no respiratory release of phosphorus into the atmosphere. |
III: | Sulphur and phosphorus cycles are sedimentary cycles. |
Which of the above statements are true?
1. I and II only
2. I and III only
3. II and III only
4. I, II, and III
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 |
Given below is an imaginary pyramid of numbers. What could be one of the possibilities about certain organisms at some of the different levels?
1. | Level PC is "insects" and level SC is "small insectivorous birds". |
2. | Level PP is "phytoplanktons" in sea and "Whale" on top level TC |
3. | Level PP is "pipal trees" and level SC is "sheep". |
4. | Level PC is "rats" and level SC is "cats". |
The accompanying figure represents an ecological pyramid. It is
1. | Pyramid of numbers in a grassland |
2. | Pyramid of biomass in a fallow land |
3. | Pyramid of biomass in a lake |
4. | Energy pyramid in a spring |
A physical structure that is characteristic of each type of ecosystem is due to:
1. | Interaction between various biotic components of the ecosystem |
2. | Interaction between various abiotic components of the ecosystem |
3. | Interaction between various biotic and abiotic components of the ecosystem |
4. | Interaction of producers with abiotic components of the ecosystem |
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 |