Root pressure is measured by

Options

A. Barometer
B. Manometer
C. Osmometer
D. Thermometer

Answer

**Step-by-Step Solution:**

1. **Understanding Root Pressure:**
- Root pressure is defined as the positive pressure that develops in the roots of plants. This pressure is generated when root hairs absorb water and minerals from the soil.

2. **Role of Root Pressure:**
- The absorbed water and minerals create a pressure gradient that facilitates the upward movement of water and nutrients through the xylem to the leaves and stems of the plant.

3. **Identifying the Instruments:**
- We need to determine which instrument among the given options is used to measure root pressure. The options provided are:
- A) Barometer
- B) Manometer
- C) Osmometer
- D) Thermometer

4. **Evaluating Each Option:**
- **A) Barometer:**
- A barometer measures atmospheric pressure, not root pressure. Therefore, this option is incorrect.

- **B) Manometer:**
- A manometer is used to measure pressure within a system, specifically the pressure in the xylem during the uptake of water. Since root pressure is related to the pressure in the xylem, this option is correct.

- **C) Osmometer:**
- An osmometer measures the osmolality of solutions, which is not related to measuring root pressure. Thus, this option is incorrect.

- **D) Thermometer:**
- A thermometer measures temperature, which does not pertain to root pressure measurement. Therefore, this option is also incorrect.

5. **Conclusion:**
- The correct instrument for measuring root pressure is the **manometer (Option B)**, as it measures the pressure in the xylem during water uptake.

**Final Answer:**
Root pressure is measured by **B) Manometer**.

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