The opening of the stomata is also aided due to the orientation of the microfibrils in the cell walls of the guard cells. Cellulose microfibrils are oriented_ rather than making it easier for the stoma to open.

Options

A. longitudinally, radially
B. radially, longitudinally
C. randomly, radially
D. randomly, longitudinally

Answer

**Step-by-Step Text Solution:**

1. **Understanding Stomata and Guard Cells:**
- Stomata are small openings on the surface of leaves that facilitate gas exchange and transpiration in plants. They are surrounded by guard cells that control their opening and closing.

2. **Role of Guard Cells:**
- Guard cells regulate the size of the stomatal pore. When guard cells take up water and become turgid, they swell and bend away from each other, causing the stomata to open. Conversely, when they lose water, they become flaccid and the stomata close.

3. **Microfibrils in Guard Cells:**
- The cell walls of guard cells contain cellulose microfibrils, which are crucial for their function. The orientation of these microfibrils affects how the guard cells change shape.

4. **Orientation of Microfibrils:**
- In guard cells, the cellulose microfibrils are oriented radially and longitudinally. This specific arrangement allows the guard cells to expand in a way that opens the stomatal pore effectively.

5. **Conclusion:**
- The correct orientation of the cellulose microfibrils in the guard cells is radial and longitudinal, which facilitates the opening of the stomata.

**Final Answer:**
The cellulose microfibrils in the cell walls of the guard cells are oriented radially and longitudinally, aiding in the opening of the stomata.

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