Cortex and pith are not distinguished in -

Options

A. Monocot stem
B. Monocot root
C. Dicot stem
D. Dicot root

Answer

To solve the question "Cortex and pith are not distinguished in -", we need to analyze the options provided and understand the structure of the different types of stems and roots in flowering plants.

### Step-by-Step Solution:

1. **Understand the Terms: Cortex and Pith**
- The cortex is the outer layer of tissue in a plant stem or root, located between the epidermis and the vascular tissue.
- The pith is the central part of the stem or root, made up of parenchyma cells.

2. **Analyze the Options:**
- **Monocot Stem:** In monocot stems, the vascular bundles are scattered throughout the ground tissue. There is no clear differentiation between the cortex and pith, meaning they are not distinctly separated.
- **Monocot Root:** Monocot roots typically have a well-defined pith, which can be large or even sclerenchymatous. This indicates that the cortex and pith can be distinguished.
- **Dicot Stem:** In dicot stems, the vascular bundles are arranged in a ring, leading to a clear distinction between the cortex and pith.
- **Dicot Root:** Dicot roots also show a clear demarcation between cortex and pith, although the pith may be reduced.

3. **Conclusion:**
- Based on the analysis, the correct answer is **Monocot Stem** (Option A) because in this structure, the cortex and pith are not distinctly separated.

### Final Answer:
Monocot Stem (Option A)

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