Q. No.Of the given two statements:
1. Only I is correct
2. Only II is correct
3. Both I and II are correct
4. Both I and II are incorrect
| I: | A constant input of solar energy is the basic requirement for almost all ecosystems to function and sustain. |
| II: | There is unidirectional movement of energy towards the higher trophic levels and its dissipation as heat to the environment. |
2. Only II is correct
3. Both I and II are correct
4. Both I and II are incorrect
Subtopic: Ecosystem Productivity | Energy Flow |
94%
Level 1: 80%+
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Consider the given two statements:
1. Only I is correct
2. Only II is correct
3. Both I and II are correct
4. Both I and II are incorrect
| I: | Primary production of an ecosystem is expressed in terms of weight (gm–2) or energy (kcal m–2). |
| II: | Productivity of an ecosystem is expressed in terms of gm–2 yr–1 or (kcal m–2) yr–1 . |
2. Only II is correct
3. Both I and II are correct
4. Both I and II are incorrect
Subtopic: Ecosystem Productivity |
90%
Level 1: 80%+
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The amount of biomass or organic matter produced per unit area over a time period by plants during photosynthesis is:
| 1. | Primary production | 2. | Primary productivity |
| 3. | Secondary production | 4. | Secondary productivity |
Subtopic: Ecosystem Productivity |
Level 3: 35%-60%
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Productivity is the rate of production of biomass expressed in terms of :
i.
ii.
iii.
iv.
| 1. | ii | 2. | iii |
| 3. | ii and iv | 4. | i and iii |
Subtopic: Ecosystem Productivity |
85%
Level 1: 80%+
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In an ecosystem, the rate of production of organic matter during photosynthesis is called as its:
| 1. | Gross Primary productivity |
| 2. | Net Primary productivity |
| 3. | Secondary productivity |
| 4. | Non productivity |
Subtopic: Ecosystem Productivity |
89%
Level 1: 80%+
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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 |
Subtopic: Ecosystem Productivity |
82%
Level 1: 80%+
Hints
The annual net primary productivity of whole biosphere is approximately:
| 1. | 25 billion tons | 2. | 55 billion tons |
| 3. | 70 billion tons | 4. | 170 billion tons |
Subtopic: Ecosystem Productivity |
88%
Level 1: 80%+
Hints
Which of the following ecosystems is most productive in terms of net primary production?
| 1. | Deserts | 2. | Tropical rainforests |
| 3. | Oceans | 4. | Estuaries |
Subtopic: Ecosystem Productivity |
86%
Level 1: 80%+
Hints
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 |
Subtopic: Ecosystem Productivity |
82%
Level 1: 80%+
Hints
What approximate percentage of the annual net primary productivity of the whole biosphere is the net primary productivity of oceans?
| 1. | 25 | 2. | 33 |
| 3. | 66 | 4. | 70 |
Subtopic: Ecosystem Productivity |
61%
Level 2: 60%+
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