Rod cells are :

Options

A. Brachysclereids
B. Macrosclerieids
C. Astrosclereids
D. Trichosclereids

Answer

**Step-by-Step Solution:**

1. **Understanding Rod Cells**: Start by identifying what rod cells are. Rod cells are specialized cells that are elongated and hair-like in structure.

2. **Analyzing the Options**: The question provides four options:
- Brachysclerides
- Macrosclerides
- Astrosclerides
- Trichosclerides

3. **Evaluating Each Option**:
- **Brachysclerides**: These are small, unbranched sclerids that are isodimetric in shape and known as stone cells. They are typically found in the cortex of plants. Therefore, this option is incorrect.
- **Macrosclerides**: These are column-shaped cells, also referred to as Malpighian cells, and are found in the epidermis. This option is also incorrect.
- **Astrosclerides**: These are branched, star-shaped cells that are found in the floating leaves of water lilies. This option is incorrect as well.
- **Trichosclerides**: These are elongated, hair-like cells that are indeed referred to as rod cells. They are found in the leaves of aerial roots. This option is correct.

4. **Conclusion**: After evaluating all the options, the correct answer to the question "Rod cells are:" is **Trichosclerides**.

**Final Answer**: Trichosclerides

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