Assertion (A): | The plants that are early seral species also tend to be wind-pollinated rather than insect-pollinated. |
Reason (R): | They are often photosynthetic plants. |
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): | Secondary succession is usually faster than primary succession. |
Reason (R): | Secondary succession is a process started by an event that reduces an already established ecosystem. |
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): | Low temperature and anaerobiosis inhibit decomposition resulting in build-up of organic chemicals. |
Reason (R): | Most decomposers are anaerobic psychrophiles. |
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. |
Sometimes the term "detritivore" is used interchangeably with:
1. | decomposers | 2. | primary consumers |
3. | secondary consumers | 4. | autotrophs |
The minimum requirement for an ecosystem to recycle nutrients present in it would be:
1. | producers |
2. | producers and decomposers |
3. | producers, primary consumers, and decomposers |
4. | producers, primary consumers, secondary consumers, and decomposers |
The best way to describe an ecosystem would be that they are:
1. | processors of energy and transformers of matter. |
2. | processors of matter and transformers of energy. |
3. | processors of matter and energy. |
4. | transformers of matter but not of energy. |
The amount of carbon dioxide in the atmosphere is:
1. increasing
2. decreasing
3. holding steady
4. fluctuating wildly
The ecosystem that can survive in the absence of the Sun would be:
1. | tropical rainforest | 2. | tundra |
3. | benthic ocean | 4. | desert |
The generation of biomass of heterotrophic (consumer) organisms in a system is termed:
1. | biogeochemical cycles | 2. | net primary productivity |
3. | gross primary productivity | 4. | secondary productivity |
Converting nitrate to nitrogen gas by anaerobes like Pseudomonas is:
1. | nitrogen fixation | 2. | ammonification |
3. | denitrification | 4. | eutrophication |