The large , empty and colourless cells present at intervals on the upper surface of grass leaf are called

Options

A. (a) Accessory cells
B. (b) Bulliform cells
C. (c) Palisade parenchyma
D. (d) Spongy parenchyma

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the name of large, empty, and colorless cells found at intervals on the upper surface of a grass leaf.

2. **Identifying the Cells**: In a transverse section of a grass leaf, we can observe various types of cells. The cells in question are characterized by being large, empty, and colorless.

3. **Recognizing Bulliform Cells**: The specific type of cells that fit this description are known as bulliform cells. These cells are located on the upper surface of the leaf and are indeed large and colorless.

4. **Function of Bulliform Cells**: The primary function of bulliform cells is to help in the rolling of the leaf lamina during dry conditions. This rolling action reduces the surface area exposed to the atmosphere, thereby minimizing water loss through transpiration.

5. **Analyzing the Options**:
- Option A: Accessory cells - These are not the correct answer as they surround stomata and assist in transpiration.
- Option B: Bulliform cells - This is the correct answer as explained.
- Option C: Palisade parenchyma - These cells are involved in photosynthesis and are not the correct answer.

6. **Conclusion**: Based on the analysis, the correct answer is **Bulliform cells**.

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