Which type of arrangement of vascular bundles occurs in the roots of monocots?

Options

A. Conjoint open
B. Radial
C. Conjoint closed
D. Bicollateral

Answer

To determine the type of arrangement of vascular bundles that occurs in the roots of monocots, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Types of Vascular Bundle Arrangements**:
- Vascular bundles can be arranged in various configurations such as conjoined open, radial, conjoined closed, and bicolateral.

2. **Identify the Arrangement in Monocot Roots**:
- In monocot roots, the vascular bundles are arranged in a specific way. The arrangement is characterized by the presence of xylem and phloem in alternating positions.

3. **Describe the Radial Arrangement**:
- In a radial arrangement, the xylem and phloem are arranged alternately. For example, one xylem element is followed by one phloem element, and this pattern continues around the central core of the root.

4. **Differentiate from Other Arrangements**:
- **Conjoined Open**: This arrangement has xylem and phloem together with a vascular cambium present, which is not found in monocot roots.
- **Conjoined Closed**: This arrangement lacks cambium and is typically found in monocot stems, not roots.
- **Bicolateral**: This arrangement has two phloem tissues with cambium rings and is found in certain plant families, not in monocot roots.

5. **Conclude the Correct Arrangement**:
- Based on the above observations, the correct type of vascular bundle arrangement in the roots of monocots is **radial**.

### Final Answer:
The type of arrangement of vascular bundles that occurs in the roots of monocots is **radial**.

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