Root pressure occurs due to

Options

A. low DPD of leaves
B. high DPD of leaves
C. osmotic flow of water into xylem and absorbing part of root
D. imbibitional flow of water into xylem of absorbing part of root .

Answer

**Step-by-Step Solution:**

1. **Understanding Root Pressure**: Root pressure is a phenomenon observed in plants, particularly in the roots, where a positive pressure is generated within the root cells. This pressure is crucial for the upward movement of water in the plant.

2. **Role of Xylem**: The xylem is the vascular tissue responsible for the transport of water and minerals from the roots to other parts of the plant. It consists of dead cells, primarily tracheids and vessels, which facilitate this movement.

3. **Active Absorption of Salts**: The process begins with the active absorption of minerals (salts) through the root hair cells. This is an energy-dependent process that allows the root cells to accumulate solutes, making them hypertonic compared to the surrounding soil solution.

4. **Water Movement into Root Hair Cells**: Due to the hypertonic nature of the root hair cells (having a higher concentration of solutes), water from the surrounding soil enters these cells through osmosis. This movement of water is driven by the concentration gradient.

5. **Continuous Inflow of Water**: As water enters the root hair cells, it creates a continuous inflow of water into the root system. This water then moves into the xylem vessels, contributing to the overall water content in the xylem.

6. **Generation of Root Pressure**: The continuous inflow of water into the xylem creates a positive pressure within the root cells. This pressure is what we refer to as root pressure, which helps push water upward through the xylem to the rest of the plant.

7. **Conclusion**: Therefore, root pressure occurs primarily due to the osmotic flow of water into the xylem as a result of the active absorption of salts by the root cells.

**Final Answer**: Root pressure occurs due to the osmotic flow of water into the xylem from the absorbing part of the root.

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