radial vascular bundles are those in which

Options

A. xylem and phloem lie on different radii
B. xylem surrounds phloem
C. phloem surrounds xylem
D. xylem and phloem lie on same radii

Answer

**Step-by-Step Solution:**

1. **Understanding Vascular Bundles**: Vascular bundles are structures in plants that facilitate the transport of materials such as water, minerals, and food. They consist of two main types of vascular tissues: xylem and phloem.

2. **Types of Vascular Tissues**:
- **Xylem**: Responsible for transporting water and minerals from the roots to other parts of the plant.
- **Phloem**: Responsible for transporting food (sugars) produced during photosynthesis from the leaves to other parts of the plant.

3. **Classification of Vascular Bundles**: Vascular bundles can be classified into four main types:
- **Collateral Vascular Bundles**: Xylem and phloem are located on the same radius.
- **Bicollateral Vascular Bundles**: Xylem is surrounded by phloem on both sides.
- **Radial Vascular Bundles**: Xylem and phloem are separated by non-vascular tissues and are located on different radii.
- **Concentric Vascular Bundles**: Xylem and phloem are arranged in a concentric manner.

4. **Focusing on Radial Vascular Bundles**: In radial vascular bundles, xylem and phloem are arranged such that they lie on different radii, meaning they are separated by non-vascular tissues. This simple arrangement allows for efficient transport without interference between the two types of tissues.

5. **Identifying the Correct Answer**: Based on the definition of radial vascular bundles, the correct answer to the question "radial vascular bundles are those in which" is that xylem and phloem are present on different radii.

**Final Answer**: Radial vascular bundles are those in which xylem and phloem are present on different radii.

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