Structures involved in radial conduction in primary dicot stem are

Options

A. Vascular bundles
B. Vascular rays
C. Medullary rays
D. Conjunctive tissue

Answer

To answer the question regarding the structures involved in radial conduction in the primary dicot stem, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Radial Conduction**:
- Radial conduction refers to the movement of water and nutrients in a horizontal direction within the plant stem. This is crucial for the distribution of resources throughout the plant.

2. **Identify Key Structures in Dicot Stem**:
- In a primary dicot stem, the main structures involved in conduction are vascular bundles, vascular rays, medullary rays, and conjunctive tissues.

3. **Focus on Medullary Rays**:
- Medullary rays, also known as pith rays, are composed of parenchyma cells that are located between the vascular bundles (xylem and phloem). These rays play a significant role in radial conduction.

4. **Role of Medullary Rays**:
- Medullary rays facilitate the movement of water and nutrients horizontally across the stem. They connect the vascular bundles with the surrounding tissues, such as the cortex and pericycle, enhancing the conduction process.

5. **Conclusion**:
- Based on the understanding of the structures involved in radial conduction, the correct answer to the question is **medullary rays**. They are the primary structures facilitating this process in the primary dicot stem.

### Final Answer:
The structures involved in radial conduction in the primary dicot stem are **medullary rays** (also known as pith rays).

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