Vascular cambium in dicot roots is

Options

A. Partly primary & partly secondary in origin
B. Completely secondary and formed from cortex
C. Completely primary and formed from pericycle
D. Formed partly from pericycle and partly from conjunctive tissue

Answer

To answer the question about the vascular cambium in dicot roots, let's break down the information step by step:

### Step-by-Step Solution:

1. **Understanding Vascular Cambium**: The vascular cambium is a type of lateral meristem that is responsible for the secondary growth in plants. It produces secondary xylem (wood) and secondary phloem (bark).

2. **Identifying the Origin in Dicot Roots**: In dicot plants, the vascular cambium in the roots originates from specific tissues. It is important to differentiate between primary and secondary origins.

3. **Primary vs. Secondary Origin**:
- **Primary Origin**: This refers to tissues that develop from the apical meristem during the initial growth of the plant.
- **Secondary Origin**: This refers to tissues that develop from lateral meristems, which contribute to the increase in thickness of the plant.

4. **Vascular Cambium in Dicot Roots**: In dicot roots, the vascular cambium is known to be completely secondary in origin. This means it does not arise from the primary meristem but rather from the differentiation of other tissues.

5. **Formation from Cortex**: The vascular cambium in dicot roots is formed from the cortical region of the plant, which lies outside the vascular tissues.

6. **Conclusion**: Based on the above points, we can conclude that the vascular cambium in dicot roots is completely secondary and formed from the cortex.

### Final Answer:
The correct option is: **completely secondary and formed from cortex**.

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