The correct sequence in primary hydrarch succession in early seral stages would be:
1. | Submerged plant – Submerged free-floating plant – Reed swamp – Marsh meadow |
2. | Submerged free-floating plant – Submerged plant – Reed swamp – Marsh meadow |
3. | Submerged plant – Submerged free-floating plant – Marsh meadow – Reed swamp |
4. | Submerged free-floating plant – Reed swamp – Submerged plant – Marsh meadow |
Which of the following ecosystem characteristics that changes during succession is not correctly matched?
|
Characteristics |
Seral stages |
Climax |
1. |
Size of individuals |
Small |
Large |
2. |
Ecological niches |
Few, generalized |
Many, specialized |
3. |
Food chains and webs |
Simple |
Complex |
4. |
Efficiency of energy use |
High |
Low |
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. |
The sequence of communities of primary succession in water is :
1. | Phytoplankton, sedges, free-floating hydrophytes, rooted hydrophytes, grasses, and trees. |
2. | Phytoplankton, free-floating hydrophytes, rooted hydrophytes, sedges, grasses, and trees. |
3. | Free-floating hydrophytes, sedges, phytoplankton, rooted hydrophytes, grasses, and trees. |
4. | Phytoplankton, rooted submerged hydrophytes, floating hydrophytes, reed swamp, sedges, meadow, and trees. |
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. |