Lysigenous cavity in monocot stem vascular bundles develops by the dissolution of

Options

A. protoxylem
B. metaxylem
C. phloem
D. ground tissue

Explanation

To answer the question about the development of lysigenous cavities in monocot stem vascular bundles, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Concept of Lysigenous Cavities**:
- Lysigenous cavities are spaces that form within plant tissues due to the dissolution of certain cells. In the context of monocot stems, these cavities are important for the plant's vascular system.

2. **Identify the Structure in Question**:
- The question asks specifically about the vascular bundles in monocot stems. Vascular bundles consist of xylem and phloem, which are crucial for water and nutrient transport.

3. **Recognize the Types of Xylem**:
- In monocots, the xylem is typically arranged in a Y-shaped configuration. Within the xylem, there are two types: protoxylem and metaxylem. Protoxylem is the first xylem to develop and is typically more fragile.

4. **Determine Which Structure Dissolves**:
- The transcript indicates that the innermost or lowermost protoxylem undergoes disintegration. This disintegration is what leads to the formation of lysigenous cavities.

5. **Conclude the Answer**:
- Therefore, the lysigenous cavity in monocot stem vascular bundles develops by the dissolution of the protoxylem.

### Final Answer:
The lysigenous cavity in monocot stem vascular bundles develops by the dissolution of the protoxylem.

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