One can differentiate the nature of guard cells between dicots and grasses by

Options

A. Its shape
B. Its secretion of chemicals
C. Its enzymatic activity
D. None of these

Answer

### Step-by-Step Solution:

1. **Understand the Context**: The question asks about differentiating guard cells between dicots and grasses (monocots). Both types of plants have stomata, which are crucial for gas exchange.

2. **Identify the Structure**: Stomata are composed of guard cells that regulate their opening and closing. The shape and structure of these guard cells can vary between different types of plants.

3. **Examine Dicot Guard Cells**: In dicot plants, the guard cells are typically **bean-shaped**. This distinctive shape is a key characteristic that helps in identifying dicots.

4. **Examine Monocot (Grass) Guard Cells**: In contrast, the guard cells in monocots (such as grasses) are generally **dumbbell-shaped**. This shape is another distinguishing feature that can be used to differentiate them from dicots.

5. **Conclusion**: The primary way to differentiate the nature of guard cells between dicots and grasses is by examining their **shape**. Dicot guard cells are bean-shaped, while monocot guard cells are dumbbell-shaped.

### Final Answer:
One can differentiate the nature of guard cells between dicots and grasses by their **shape**.

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