| 1. | All organisms in the pond rely only on dissolved inorganic substances for nutrition. |
| 2. | Energy circulates indefinitely within the pond without any loss as heat. |
| 3. | It contains producers, consumers, and decomposers that continuously recycle matter. |
| 4. | Autotrophs and decomposers do not depend on any abiotic factors. |
| 1. | Different species occupy distinct vertical layers, reducing direct competition for light and space. |
| 2. | All plant species grow at the same height to maximise total ecosystem productivity. |
| 3. | Trees, shrubs, herbs, and grasses compete for identical resources within a single vertical layer. |
| 4. | Vertical layers are formed only in aquatic ecosystems and never in terrestrial ones. |
| 1. | Energy flows in multiple directions between all trophic levels. |
| 2. | Energy is cyclic, with decomposers returning it to autotrophs. |
| 3. | Energy is only transferred between autotrophs and primary consumers, excluding other trophic levels. |
| 4. | Energy flow is unidirectional, moving from autotrophs to heterotrophs and eventually dissipating as heat. |