Which one of the following have amphivasal vascular bundles?

Options

A. Cycas and Dryopteris
B. Dracaena and Yucca
C. Helianthus and Cucurbita
D. Maize and Wheat

Answer

To determine which plant has amphivasal vascular bundles, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Vascular Bundles**: Vascular bundles are structures that contain xylem and phloem, which are responsible for the transport of water, nutrients, and food in plants. They can be classified into different types based on their arrangement.

2. **Identify Types of Vascular Bundles**:
- **Collateral Vascular Bundles**: Xylem and phloem are on the same radius, with phloem on the outer side and xylem on the inner side.
- **Bicollateral Vascular Bundles**: Phloem is present on both sides of the xylem.
- **Concentric Vascular Bundles**: One type surrounds the other, which can be further classified into amphicribal and amphivasal.

3. **Focus on Amphivasal Vascular Bundles**: Amphivasal vascular bundles are characterized by having phloem in the center and xylem surrounding it. This is the opposite of amphicribal bundles, where xylem is in the center.

4. **Identify Examples of Amphivasal Bundles**: According to the information provided, amphivasal vascular bundles are found in plants like **Dracaena** and **Yucca**.

5. **Conclusion**: Based on the classification and examples, the correct answer to the question is that **Dracaena** and **Yucca** have amphivasal vascular bundles.

### Final Answer:
The plants that have amphivasal vascular bundles are **Dracaena** and **Yucca**.

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