The main role of vascular rays is

Options

A. Lateral conduction of ergastic materials
B. Upward conduction of water and salts
C. Downward conduction of food materials
D. Radial movement of water and food

Answer

**Step-by-Step Solution:**

1. **Understanding Vascular Rays**: Vascular rays are specialized structures in plants that consist of parenchyma cells. They extend radially from the cambium into the xylem and phloem.

2. **Function of Vascular Rays**: The primary function of vascular rays is to facilitate the movement of substances within the plant. They play a crucial role in the radial conduction of materials.

3. **Types of Movement**:
- **Radial Movement**: This refers to the movement of water and nutrients across the plant, specifically from the xylem (which conducts water) and phloem (which conducts food).
- **Upward and Downward Movement**: While xylem is responsible for upward conduction of water and phloem for downward conduction of food, vascular rays specifically assist in the lateral or radial movement.

4. **Analyzing Options**:
- **Lateral conduction of ergastic materials**: This option is misleading as it does not accurately describe the function of vascular rays.
- **Upward conduction of water and salts**: This is primarily the function of xylem, not vascular rays.
- **Downward conduction of food materials**: This is mainly the role of phloem, not specifically the vascular rays.
- **Radial movement of water and food**: This option accurately describes the function of vascular rays, as they facilitate the movement of both water and nutrients across the plant.

5. **Conclusion**: Based on the analysis, the main role of vascular rays is the radial movement of water and food materials.

**Final Answer**: The main role of vascular rays is the radial movement of water and food.

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