Large,empty colourless cells of the adaxial epidermis along the veins of grass leaves are

Options

A. Lenticels
B. Guard cells
C. Bundle sheath cells
D. Bulliform cells

Answer

To solve the question regarding the large, empty colorless cells of the adaxial epidermis along the veins of grass leaves, we will analyze each option provided.

### Step-by-Step Solution:

1. **Understanding the Question**: We need to identify the type of cells that are large, empty, and colorless, specifically located in the adaxial (upper) epidermis of grass leaves along the veins.

2. **Analyzing Option 1 - Lenticles**:
- Lenticles are specialized structures that facilitate gas exchange between the internal tissues of the plant and the atmosphere.
- They are not large empty colorless cells but rather pores.
- **Conclusion**: This option is incorrect.

3. **Analyzing Option 2 - Guard Cells**:
- Guard cells are responsible for regulating the opening and closing of stomata, which are small openings on the leaf surface that allow for gas exchange.
- They are not large or empty; instead, they are specialized cells that control the size of the stomatal pore.
- **Conclusion**: This option is incorrect.

4. **Analyzing Option 3 - Bundle Sheath Cells**:
- Bundle sheath cells are involved in the photosynthetic process, particularly in C4 plants, and are rich in the enzyme Rubisco.
- They are not characterized as large, empty, or colorless cells.
- **Conclusion**: This option is incorrect.

5. **Analyzing Option 4 - Bulliform Cells**:
- Bulliform cells are large, bubble-shaped epidermal cells found in the upper epidermis of grass leaves, particularly near the midrib.
- They are indeed large, empty, and colorless, and they play a role in the leaf's ability to fold and unfold, which helps in water conservation.
- **Conclusion**: This option is correct.

### Final Answer:
The correct answer is **Option 4 - Bulliform Cells**.

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