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Q. No.
Assertion(A): It is convenient to divide the global ecosystem into some basic categories.
Reason(R): Global ecosystem is too big to study at once.
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. (A) is false, but (R) is true.
Subtopic: Introduction |
89%
Level 1: 80%+
Hints
Assertion(A): Primary productivity depends on a variety of environmental factors.
Reason(R): Primary productivity varies in different types of 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. (A) is false, but (R) is true.
Reason(R): Primary productivity varies in different types of 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. (A) is false, but (R) is true.
Subtopic: Ecosystem Productivity |
57%
Level 3: 35%-60%
Hints
Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R).
In the light of the above statements, choose the most appropriate answer from the options given below:
| Assertion (A): | The food chain or food web exists in ecosystems. |
| Reason (R): | Death of organism is the beginning of the Grazing food chain/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. | (A) is False, but (R) is True. |
Subtopic: Ecological Flow |
77%
Level 2: 60%+
Hints
Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R).
In the light of the above statements, choose the most appropriate answer from the options given below:
| Assertion (A): | Earthworms help in the breakdown of complex organic matter as well as in the loosening of the soil. |
| Reason (R): | Earthworms being referred to as the farmer’s ‘friend’. |
| 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. | (A) is False, but (R) is True. |
Subtopic: Decomposition |
58%
Level 3: 35%-60%
Hints
Assertion(A): The pyramid of energy is always upright.
Reason(R): When energy flows from a particular trophic level to the next trophic level, some energy is always lost as heat at each step.
Choices for Assertions and reasons:
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. (A) is false, but (R) is true.
Reason(R): When energy flows from a particular trophic level to the next trophic level, some energy is always lost as heat at each step.
Choices for Assertions and reasons:
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. (A) is false, but (R) is true.
Subtopic: Ecological Pyramids |
90%
Level 1: 80%+
Hints
Assertion(A): The biomass of fishes far exceeds that of phytoplankton in sea.
Reason(R): The pyramid of biomass in sea is generally inverted.
Choices for Assertions and reasons:
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. (A) is false, but (R) is true.
Reason(R): The pyramid of biomass in sea is generally inverted.
Choices for Assertions and reasons:
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. (A) is false, but (R) is true.
Subtopic: Ecological Pyramids |
50%
Level 3: 35%-60%
Hints
Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R).
In the light of the above statements, choose the most appropriate answer from the options given below:
| Assertion (A): | The organisms which depend on producers for nutritional requirements are called primary consumers and are also called heterotrophs. |
| Reason (R): | All animals depend on plants directly for their food needs. |
| 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. | (A) is False, but (R) is True. |
Subtopic: Energy Flow |
70%
Level 2: 60%+
Hints
Assertion(A): The energy trapped by the producer is either passed on to a consumer or the organism dies.
Reason(R): No energy that is trapped in an organism remains in it forever.
Choices for Assertions and reasons:
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. (A) is false, but (R) is true.
Reason(R): No energy that is trapped in an organism remains in it forever.
Choices for Assertions and reasons:
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. (A) is false, but (R) is true.
Subtopic: Ecological Flow |
77%
Level 2: 60%+
Hints
Given below are two statements
In light of the above statements, choose the most appropriate answer from the options given below
1. Both statement I and statement II are correct
2. Both statement I and statement II are incorrect
3. Statement I is correct but statement II is incorrect
4. Statement I is incorrect but statement II is correct
| Statement I: | The pyramid of energy is always upright, can never be inverted |
| Statement II: | When energy flows from one trophic level to next trophic level, some energy is always lost as heat |
In light of the above statements, choose the most appropriate answer from the options given below
1. Both statement I and statement II are correct
2. Both statement I and statement II are incorrect
3. Statement I is correct but statement II is incorrect
4. Statement I is incorrect but statement II is correct
Subtopic: Energy Flow |
92%
Level 1: 80%+
Hints
Choose the correct statements
A. Length of the food chain is generally limited to 3-4 trophic levels due to energy loss.
B. Length of food chain depends upon the producer
C. In hydrarch succession, lichen is the pioneer community
D. Removal of most of the carnivores in an ecosystem results in an increased population of deer
E. Removal of 80% of top carnivores results in greatly increased growth of vegetation
Choose the correct answer from the options given below
1. A, B and C only
2. C, D and E only
3. A, D and E only
4. A, B and D only
A. Length of the food chain is generally limited to 3-4 trophic levels due to energy loss.
B. Length of food chain depends upon the producer
C. In hydrarch succession, lichen is the pioneer community
D. Removal of most of the carnivores in an ecosystem results in an increased population of deer
E. Removal of 80% of top carnivores results in greatly increased growth of vegetation
Choose the correct answer from the options given below
1. A, B and C only
2. C, D and E only
3. A, D and E only
4. A, B and D only
Subtopic: Energy Flow | Ecological Pyramids |
66%
Level 2: 60%+
Hints
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