Each stoma is surrounded by

Options

A. passage cells
B. Guard cells
C. Parenchyma cells
D. Lenticels

Answer

To answer the question "Each stoma is surrounded by," we will analyze the options provided and identify the correct one step by step.

### Step-by-Step Solution:

1. **Understanding the Structure of Stomata**:
- Stomata are small openings found on the surfaces of leaves and stems that facilitate gas exchange (carbon dioxide and oxygen) in plants.

2. **Identifying the Components**:
- The options given are:
- A) Passage cells
- B) Guard cells
- C) Parenchyma cells
- D) Lenticles

3. **Evaluating Each Option**:
- **A) Passage Cells**: These are thin-walled cells found in the endodermis of vascular plants. They are not directly involved in the structure of stomata.
- **B) Guard Cells**: These are specialized cells that surround each stoma. They are responsible for regulating the opening and closing of the stomatal pore, allowing for gas exchange. They are typically kidney-shaped and function in pairs.
- **C) Parenchyma Cells**: These are general plant cells that have a primary cell wall and are involved in various functions, including storage and tissue repair. They do not specifically surround stomata.
- **D) Lenticles**: These are small openings found in the stems of woody plants that facilitate gas exchange. They are not related to stomata.

4. **Conclusion**:
- After evaluating all the options, the correct answer is **B) Guard cells**. Each stoma is indeed surrounded by guard cells.

### Final Answer:
Each stoma is surrounded by **guard cells**.

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