| 1. | Fragmentation | 2. | Leaching |
| 3. | Catabolism | 4. | Humification |
| 1. | Organism | 2. | Population |
| 3. | Cell | 4. | Biomolecules |
| Assertion (A): | Organisms at each trophic level depend on those at the lower trophic level for their energy demands. |
| Reason (R): | The amount of energy decreases at successive trophic levels. |
| 1. | Both (A) and (R) are true and (R) correctly explains the (A). |
| 2. | (A) is true but (R) is false |
| 3. | (A) is false but (R) is true |
| 4. | Both (A) and (R) are true but (R) does not correctly explain the (A). |
| I: | conversion of inorganic into organic material, with the help of the radiant energy of the sun, by the autotrophs |
| II: | consumption of the autotrophs by heterotrophs; |
| III: | decomposition and mineralization of the dead matter to release them back for reuse by the autotrophs. |