Rod cells are :

Options

A. Brachysclereids
B. Macrosclerieids
C. Astrosclerids
D. Trichosclerids

Answer

**Step-by-Step Solution:**

1. **Understanding Rod Cells**: Rod cells, also known as macrosclerates, are a type of sclerenchyma cell. They are characterized by their elongated, rod-like shape.

2. **Identifying the Function**: Rod cells provide structural support to the plant. They are a reduced form of sclerenchyma and are important for the mechanical strength of various plant parts.

3. **Location of Rod Cells**: These cells are typically found in the outer layer of the seed coat of legumes. Their presence helps protect the seed and contributes to its overall strength.

4. **Distinguishing from Other Cell Types**: It is important to differentiate rod cells from other types of sclerenchyma cells, such as brachysclerids (stone cells) which are more rounded and provide different types of support.

5. **Conclusion**: Therefore, rod cells are elongated sclerenchyma cells found in the outer layer of legume seed coats, providing mechanical support.

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