A dicot root differs from a monocot root in which of the following -

Options

A. Presence of piliferous layer
B. Presence of exodermis
C. Presence of ill-developed pith
D. Separate radial vascular bundle

Answer

To determine how a dicot root differs from a monocot root, we need to analyze the characteristics of both types of roots. Here’s a step-by-step solution:

### Step 1: Understand the Structure of Dicot Roots
Dicot roots typically have a specific arrangement of vascular bundles. In dicots, the xylem and phloem are arranged in a radial pattern, forming a distinct structure.

### Step 2: Identify the Vascular Bundle Arrangement
In dicots, the vascular bundles are arranged in a star-like pattern with xylem located at the center and phloem located between the arms of the xylem. This is different from monocots, where vascular bundles are scattered throughout the stem.

### Step 3: Examine the Presence of Pith
In dicot roots, the pith is generally absent. This is an important distinguishing feature because monocot roots usually have a well-developed pith.

### Step 4: Analyze the Presence of Other Layers
- **Filiparous Layer**: This layer is not a distinguishing feature between dicots and monocots.
- **Exodermis**: This layer is present in both types of roots but is more developed in monocots.
- **Ill-Developed Sphincter**: This term is not commonly used in the context of root anatomy and may refer to structures that are not typically compared between dicots and monocots.

### Step 5: Identify the Correct Option
Based on the analysis:
- Option A (Filiparous layer): Not a distinguishing feature.
- Option B (Exodermis layer): Present in both.
- Option C (Ill-developed sphincter): This is not a standard term used for root anatomy.
- Option D (Separate radial vascular bundle): This is characteristic of dicots.

Thus, the correct answer to the question is **Option D: Separate radial vascular bundle**.

### Summary
A dicot root differs from a monocot root primarily in the arrangement of vascular bundles, where dicots have separate radial vascular bundles.

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