Absorption of water by velamen roots is due to

Options

A. Endosmosis
B. Deplasmolysis
C. Transpiration
D. Imbibition

Answer

To solve the question regarding the absorption of water by velamen roots, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Velamen Roots**: Velamen roots are specialized aerial roots found in certain plants, particularly epiphytes like orchids. They have a unique structure that helps in water absorption.

2. **Structure of Velamen**: The outer layer of velamen roots consists of several layers of dead cells. This structure is designed to absorb water efficiently from the environment, especially in humid conditions.

3. **Mechanism of Water Absorption**: The primary mechanism by which velamen roots absorb water is through a process called **imbibition**. Imbibition is the process where water is absorbed by a solid or gel, causing it to swell. In the case of velamen roots, the dead cells of the velamen layer can absorb water from the atmosphere.

4. **Comparing Other Options**:
- **Endosmosis** refers to the movement of water into a cell, which is not the primary mechanism for velamen roots.
- **Diplososmosis** is not a commonly recognized term in plant physiology.
- **Transpiration** is the process of water movement through a plant and its evaporation from aerial parts, which is not directly related to the absorption by velamen roots.

5. **Conclusion**: Based on the structure and function of velamen roots, the correct answer to the question is that the absorption of water by velamen roots is due to **imbibition**.

### Final Answer:
The absorption of water by velamen roots is due to **imbibition**.

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