vascular bundles of typical leaves are

Options

A. collateral and closed
B. collateral and open
C. conjoint and concentric
D. radial

Answer

To answer the question about the vascular bundles of typical leaves, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Types of Vascular Bundles**:
- Vascular bundles can be classified based on their arrangement and the presence of cambium. The main types are co-lateral (open and closed), conjoined and co-centric, and radial.

2. **Analyze the Options**:
- **Co-lateral and Closed**: In this type, the xylem and phloem are located on the same radius, and there is no cambium present. This type is typically found in monocot stems and leaves.
- **Co-lateral and Open**: Similar to co-lateral and closed, but here the cambium is present. This type is usually found in dicot stems.
- **Conjoined and Co-centric**: This type does not exist in any known plant species.
- **Radial**: In this arrangement, xylem and phloem are located on different radii. This type is generally found in roots.

3. **Identify the Correct Type for Leaves**:
- Since the question specifically asks about typical leaves, we need to determine which type of vascular bundle is present in leaves. The co-lateral and closed type is found in monocot leaves, while the co-lateral and open type is found in dicot stems.

4. **Conclusion**:
- The correct answer is that vascular bundles of typical leaves are **co-lateral and closed**.

### Final Answer:
Vascular bundles of typical leaves are co-lateral and closed.

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