Vascular cambium ring of dicot stem is formed by

Options

A. Primary meristem only
B. Secondary meristem only
C. Both primary and secondary meristem
D. Xylem and phloem

Answer

To solve the question regarding the formation of the vascular cambium ring in dicot stems, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Structure of Dicot Stems**:
- Dicot stems have a unique structure that differentiates them from monocots. They possess both primary and secondary growth.

2. **Identify the Types of Cambium**:
- In dicot stems, the cambium is classified into two types based on their origin:
- **Intrafascicular Cambium**: This is the cambium found between the xylem and phloem within the vascular bundles. It has a primary origin.
- **Interfascicular Cambium**: This is the cambium that forms between the vascular bundles and has a secondary origin.

3. **Determine the Composition of Vascular Cambium**:
- The vascular cambium in dicot stems is formed by both intrafascicular and interfascicular cambium. This means it has contributions from both primary and secondary meristems.

4. **Conclusion**:
- Therefore, the vascular cambium ring of the dicot stem is formed by both primary and secondary meristems.

### Final Answer:
The vascular cambium ring of the dicot stem is formed by both primary and secondary meristems.

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