Plants adapted to low light intensity have

Options

A. Leaves modified to spines
B. Large photosynthetic unit size than the sun plants
C. Higher rate of `CO_(2)` fixation than the sun plants
D. More extended root system

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the characteristics of plants that are adapted to low light intensity.

2. **Identifying Options**: The options provided are:
- Leaves modified to a sponge
- Larger photosynthetic unit size than sun plants
- Higher rate of CO2 fixation than sun plants
- More extended root system

3. **Analyzing Each Option**:
- **Leaves modified to a sponge**: This is not a typical adaptation for low light; rather, it refers to plants that may need to retain moisture.
- **Larger photosynthetic unit size than sun plants**: Plants adapted to low light often have larger photosynthetic units to maximize light absorption.
- **Higher rate of CO2 fixation than sun plants**: Generally, plants in low light do not have a higher rate of CO2 fixation compared to those in high light.
- **More extended root system**: While some plants may have extended root systems, this is not a defining characteristic of low light adaptation.

4. **Conclusion**: The most appropriate answer is that plants adapted to low light intensity have a larger photosynthetic unit size than sun plants. This adaptation helps them capture as much light as possible in their low light environment.

5. **Final Answer**: Plants adapted to low light intensity have larger photosynthetic unit sizes than sun plants.

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