Which of the following is not true for the vascular bundles of monocotyledonous stems?

Options

A. Scattered in the ground tissue
B. Possess water-containing cavities
C. Ring' arrangement
D. Conjoint and closed

Answer

To answer the question regarding which statement is not true for the vascular bundles of monocotyledonous stems, we can analyze the characteristics of these vascular bundles step by step.

### Step-by-Step Solution:

1. **Understanding Vascular Bundles**:
- Vascular bundles consist of xylem and phloem, which are responsible for the transport of water and nutrients in plants.

2. **Characteristics of Monocot Vascular Bundles**:
- In monocotyledonous plants, the vascular bundles are typically scattered throughout the ground tissue rather than arranged in a ring.
- They are usually described as conjoint, meaning that xylem and phloem are found together in the same bundle.
- Monocot vascular bundles are generally closed, which means they do not have cambium between the xylem and phloem, preventing secondary growth.

3. **Analyzing the Options**:
- **Scattered in the ground tissue**: This is true for monocots.
- **Possess water cavities**: This is also true.
- **Ring arrangement**: This is not true; monocots do not have vascular bundles arranged in a ring.
- **Conjoint and closed**: This is true; they are conjoint but they are closed.

4. **Identifying the Incorrect Statement**:
- The statement that is not true for the vascular bundles of monocotyledonous stems is "ring arrangement". Monocots have scattered vascular bundles, not arranged in a ring.

### Conclusion:
The correct answer to the question is that the vascular bundles of monocotyledonous stems do not have a "ring arrangement".

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