In the internal structure of sunflower stem, in between the vascular bundles there are a few layers of radially placed (A)_______cells, which constitute (B)_______.

Answer

To answer the question regarding the internal structure of the sunflower stem, we will break it down step by step.

### Step-by-Step Solution:

1. **Understanding the Structure of the Sunflower Stem**:
- The sunflower is a dicot plant, which means its stem has a specific internal structure that includes vascular bundles.

2. **Identifying the Cells Between Vascular Bundles**:
- In the internal structure of the sunflower stem, there are layers of cells that are radially placed between the vascular bundles.

3. **Naming the Cells**:
- The cells that are found in between the vascular bundles are known as **parenchyma cells**. These cells are a type of permanent tissue that is typically involved in storage, photosynthesis, and tissue repair.

4. **Understanding What These Cells Constitute**:
- The parenchyma cells arranged in between the vascular bundles form a structure known as **medullary rays**. These rays are important for the transport of nutrients and water between the vascular bundles and the pith of the stem.

5. **Final Answer**:
- Therefore, for the blanks in the question:
- (A) is **parenchyma** cells.
- (B) is **medullary rays**.

### Final Answer:
(A) parenchyma (B) medullary rays.

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