Approximately how much of the solar energy that falls on the leaves of a plant is converted to chemical energy by photosynthesis?

Options

A. Less than 1%
B. 2 - 10%
C. 0.3
D. 0.5

Answer

To determine how much solar energy that falls on the leaves of a plant is converted to chemical energy by photosynthesis, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Source of Energy**:
- The sun is the ultimate source of energy for nearly all ecosystems, except for deep hydrothermal ecosystems.

2. **Understand Solar Radiation**:
- When sunlight reaches the plant, not all of it is usable for photosynthesis. Less than 50% of the total incident solar radiation is classified as Photosynthetically Active Radiation (PAR).

3. **Define Photosynthetically Active Radiation (PAR)**:
- PAR refers to the portion of sunlight that plants can use for photosynthesis, which is crucial for converting solar energy into chemical energy.

4. **Estimate Energy Conversion**:
- Of the PAR that reaches the plant, approximately 2% to 10% (or sometimes cited as 1.1% to 5%) of the solar energy is captured by autotrophs (plants) and converted into chemical energy through the process of photosynthesis.

5. **Conclusion**:
- Therefore, the approximate percentage of solar energy converted to chemical energy by photosynthesis in plants is between 2% and 10%.

### Final Answer:
Approximately 2% to 10% of the solar energy that falls on the leaves of a plant is converted to chemical energy by photosynthesis.

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