A vascular bundle which lacks cambium is called

Options

A. Conjoint , and collateral
B. Conjoint , but not collateral
C. Closed , and collateral
D. Bicollateral

Answer

To solve the question "A vascular bundle which lacks cambium is called:", we can follow these steps:

### Step-by-Step Solution:

1. **Understand Vascular Bundles**: Vascular bundles are arrangements of xylem and phloem in plants. They play a crucial role in the transport of water, nutrients, and food.

2. **Identify Types of Vascular Bundles**: Vascular bundles can be classified into two main categories:
- **Conjoined (or Mixed)**: Where xylem and phloem are found together.
- **Radial**: Where xylem and phloem are arranged separately.

3. **Focus on Cambium**: Cambium is a layer of tissue that allows for secondary growth in plants. Its presence or absence determines whether a vascular bundle is open or closed for growth.

4. **Closed vs. Open Vascular Bundles**:
- **Open Vascular Bundles**: These contain cambium and can undergo secondary growth (e.g., dicot stems).
- **Closed Vascular Bundles**: These lack cambium and do not allow for secondary growth (e.g., monocot stems).

5. **Conclusion**: Since the question specifically asks for a vascular bundle that lacks cambium, the correct term is "closed vascular bundle."

### Final Answer:
A vascular bundle which lacks cambium is called a **closed vascular bundle**.

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