The ultimate energy source of all ecosystem is

Options

A. producers
B. organic molecules
C. carbohydrate
D. solar radiation.

Answer

**Step-by-Step Solution:**

1. **Understanding Ecosystem**: An ecosystem consists of both biotic (living organisms) and abiotic (non-living components) factors. It is a community where interactions occur between these components.

2. **Trophic Levels**: In an ecosystem, organisms are organized into trophic levels. The primary producers (like plants) form the first level, followed by primary consumers (herbivores), and then secondary consumers (carnivores).

3. **Energy Transfer**: Energy flows through these trophic levels. Primary producers convert sunlight into energy through photosynthesis, which is then passed on to primary consumers when they eat the producers.

4. **Source of Energy for Producers**: The primary producers, which are at the base of the food chain, rely on sunlight as their energy source. They use solar energy to create organic molecules through photosynthesis.

5. **Conclusion**: Since the primary producers are the first step in the energy flow of an ecosystem and they derive their energy from sunlight, the ultimate energy source for all ecosystems is solar radiation.

**Final Answer**: The ultimate energy source of all ecosystems is solar radiation.

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