Question

Which of the following is not recycled in the ecosystem?
A. Nitrogen
B. Water
C. Energy
D. Oxygen

Answer 1

Hint: An ecosystem is a system of living organisms as well as with the nonliving components of their environment. These biotic and abiotic components come together for nutrient cycles and energy flows.

Complete Answer:
- Ecosystems are regulated by external and internal factors. External factors like climate, parent material, control the ecosystem but not control by ecosystem.
- On the other hand internal factors are controlled like decomposition, root competition, shading, disturbance, succession, and the types of species present.
- Nitrogen, oxygen, carbon, phosphorus, sulfur are vital compounds which are recycled in the ecosystem through biogeochemical cycles.
- These compounds transfer from producer to consumer to decomposer and then again into the environment. In the similar way water is also recycled in the ecosystem by water cycle.
- Energy is not recycled in the ecosystem. From one level to another level there is only 10% energy is further transfer and another 90% used in the process.

So, the correct answer is 'Energy’.

Note: Energy and carbon are the part of ecosystems by photosynthesis, and carried to other organisms that feed on the living and dead plant matter, and eventually released through respiration.
The plants which are alive act as primary producers; they have the energy which is consumed by the animals. If these plants are dead then they become detritus. Alive plants enter into a plant-based trophic system and if die then enter the detritus-based trophic system.