Indicate the flow of energy in an ecosystem. Why is it unidirectional ?
Justify.

Explanation

### Step-by-Step Solution:

1. **Understanding Energy Flow in an Ecosystem**:
- Energy flow in an ecosystem can be illustrated through a food chain. For example, consider a simple food chain: grass → grasshopper → frog → snake → eagle.
- In this chain, grass (a producer) captures solar energy through photosynthesis and converts it into chemical energy.

2. **Energy Conversion and Transfer**:
- The grass utilizes about 1% of the solar energy that reaches it. This energy is converted into organic matter.
...