Transpiration is measured by

Options

A. Potometer
B. Porometer
C. Osmometer
D. Test tube

Answer

**Step-by-Step Solution:**

1. **Understanding Transpiration**: Transpiration is the process by which water vapor is lost from the aerial parts of plants, mainly through small openings called stomata.

2. **Identifying Measurement Tools**: To measure the rate of transpiration, specific tools are used. The options provided are:
- Potometer
- Porometer
- Osmometer
- Test Tube

3. **Analyzing Each Tool**:
- **Potometer**: This is an instrument specifically designed to measure the rate of water uptake by a plant, which is closely related to the rate of transpiration.
- **Porometer**: This device measures the porosity of materials and is not used for measuring transpiration.
- **Osmometer**: This tool is used to measure osmotic potential in solutions, not for measuring transpiration.
- **Test Tube**: A test tube is a laboratory glassware used for holding and mixing substances, but it does not measure transpiration.

4. **Conclusion**: Based on the analysis, the correct tool for measuring transpiration is the **Potometer**.

5. **Final Answer**: Transpiration is measured by **Potometer**.

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