In a dicot root , vascular cambium is

Options

A. completely primary
B. partially primary and partially secondary
C. completely secondary
D. Sometimes primary something secondary

Answer

To solve the question regarding the vascular cambium in a dicot root, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Vascular Cambium**:
- 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 Structure in Dicot Roots**:
- In dicot roots, the vascular cambium is primarily responsible for the formation of secondary vascular tissues.

3. **Analyzing the Options**:
- **Option A: Completely primary** - This is incorrect as monocot roots have primary vascular tissues and lack vascular cambium.
- **Option B: Partially primary and partially secondary** - This is true for dicot stems, not roots.
- **Option C: Completely secondary** - This is the correct option for dicot roots, where the vascular cambium leads to the formation of secondary xylem and phloem, replacing the primary tissues.
- **Option D: Sometimes primary, sometimes secondary** - This condition is not applicable to dicot roots; it describes the situation in dicot stems.

4. **Conclusion**:
- The correct answer is that in a dicot root, the vascular cambium is **completely secondary**. This means that the primary tissues have been replaced by secondary vascular tissues.

### Final Answer:
In a dicot root, the vascular cambium is completely secondary.

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