Guttation is caused by

Options

A. transpiration
B. high root pressure
C. high leat pressure
D. clogged xylem elements

Answer

**Step-by-Step Solution:**

1. **Understanding Guttation**: Guttation is the process by which water is lost from the plant in liquid form, specifically from the tips of leaves. This occurs when water droplets are exuded from the leaf margins.

2. **Conditions for Guttation**: Guttation typically happens under conditions of low transpiration. Transpiration is the process of water vapor loss from the plant, primarily through stomata. When transpiration is low, the plant retains more water.

3. **Role of Hydrothodes**: The water is released through specialized structures called hydrothodes, which can also be referred to as water stomata. These structures are found at the leaf tips and are responsible for the exudation of water.

4. **Influence of Root Pressure**: The main driving force behind guttation is high root pressure. Root pressure is generated when water is absorbed by the roots and creates a pressure that pushes water upward through the plant. When this pressure is sufficiently high, it can lead to the exudation of water droplets from the hydrothodes.

5. **Conclusion**: Based on the understanding of guttation, it is clear that the correct answer to the question "Guttation is caused by" is **high root pressure**.

**Final Answer**: Guttation is caused by high root pressure.

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