Q. No.Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A):
Some aquatic ecosystems have inverted biomass pyramids.
Reason (R):
The pyramid of energy is also inverted in such ecosystems.
In the light of the above statements, choose the most appropriate answer from the options given below :
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.
| Assertion (A): | Saprophytes play a vital role in the ecosystem. |
| Reason (R): | Saprophytes are accorded the highest trophic level in a food chain or a food web. |
| 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. |
| Assertion (A): | Lichens are commonly the pioneer species during primary succession on rocks. |
| Reason (R): | Lichens are able to secrete acids to dissolve rocks. |
| 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. |
- If both the assertion and the reason are true and the reason is a correct explanation of the assertion
- If both the assertion and reason are true but the reason is not a correct explanation of the assertion
- If the assertion is true but the reason is false
- If both the assertion and reason are false
Net primary productivity is the gross primary productivity minus:
| 1. | that which is consumed by herbivores |
| 2. | that which is consumed by the producer in metabolism |
| 3. | secondary productivity |
| 4. | loss due to mortality |
An important feature of the phosphorus cycle is that its reservoir is in:
1. aquifers
2. soil and rocks
3. the atmosphere
4. the sun
In an open ocean, the pyramid of biomass is often inverted. How can this support higher trophic levels?
| 1. | The food produced by primary producers is of high quality |
| 2. | The primary producers grow and reproduce at high rates |
| 3. | Primary producers are very abundant. |
| 4. | The predators at higher trophic levels are very efficient |
If the carbon atoms fixed by producers already have passed through three species, the trophic level of the last species would be
| 1. | Scavenger | 2. | Tertiary producer |
| 3. | Tertiary consumer | 4. | Secondary consumer |
Climax community is in a state of :
1. Non-equilibrium
2. Equilibrium
3. Disorder
4. Constant change
During the process of ecological succession, the changes that take place in communities are :
1. Orderly and sequential
2. Random
3. Very quick
4. Not influenced by the physical environment
Among the following, where do you think the process of decomposition would be the fastest?
| 1. | Tropical rain forest | 2. | Antarctic |
| 3. | Dry arid region | 4. | Alpine region |
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