In dicots, primary root is formed by

Options

A. direct elongation of radicle
B. direct elongation of plumule
C. elongation of epicotyl
D. parts other than radicle

Answer

To answer the question "In dicots, primary root is formed by," we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Structure of a Dicot Seed**:
- In dicots, the seed contains an embryonal axis, which is divided into two main parts: the radical and the plumeule.

2. **Identifying the Parts**:
- The **radical** is the part of the embryonal axis that will develop into the primary root.
- The **plumeule** is the part that will develop into the primary shoot (stem).

3. **Function of the Radical**:
- The radical is responsible for the formation of the primary root. It is the structure that grows downwards into the soil to anchor the plant and absorb water and nutrients.

4. **Protection of the Radical**:
- The radical is enclosed in a protective sheath called the **colioriza**, which helps protect it as it grows.

5. **Conclusion**:
- Therefore, the primary root in dicots is formed from the radical part of the embryonal axis.

6. **Choosing the Correct Option**:
- Based on the information, the correct answer to the question is that the primary root is formed by the radical.

### Final Answer:
The primary root in dicots is formed by the **radical**.

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