In an ecosystem, which one shows one-way passage

Options

A. Free energy
B. Carbon
C. Nitrogen
D. potassium

Explanation

**Step-by-Step Solution:**

1. **Understanding the Ecosystem:** In an ecosystem, various elements such as energy, nutrients, and matter interact. Each of these elements has a different flow pattern.

2. **Identifying the Options:** The question provides four options:
- Free energy
- Carbon
- Nitrogen
- Potassium

3. **Analyzing Energy Flow:** Among these options, we need to focus on how energy flows through an ecosystem. Energy enters the ecosystem primarily through sunlight, which is captured by producers (like plants) during photosynthesis.

4. **The 10% Law:** According to the 10% law proposed by Mr. Lindman, only about 10% of the energy is transferred from one trophic level to the next. This means that as energy moves through the food chain—from producers to primary consumers, then to secondary consumers, and so forth—most of the energy is lost (approximately 90%) at each level due to metabolic processes like respiration and digestion.

5. **Conclusion on One-Way Passage:** Since energy does not cycle back in the same form but rather dissipates as heat and is lost at each trophic level, it demonstrates a one-way passage. Therefore, the correct answer to the question is "free energy," as it is the only option that shows a one-way flow in an ecosystem.

**Final Answer:** Free energy shows a one-way passage in an ecosystem.

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