Select an incorrect statement about stomata

Options

A. number of such tiny pores varies from 10 to 60 per cm2 of the leaf surface.
B. in grasses the stomatal density is almost the same on both the surfaces of leaf.
C. guard cells are special types of epidermal cells
D. size of a typical stomatal pore ranges from 3-12 um in width and from 10-14 um in length.

Answer

**Step-by-Step Solution:**

1. **Understanding Stomata**: Stomata are tiny pores located on the epidermal layer of leaves, primarily involved in the exchange of gases (like oxygen and carbon dioxide) between the plant and its environment.

2. **Structure of Stomata**: Each stoma is surrounded by a pair of specialized cells known as guard cells. These guard cells control the opening and closing of the stomata, thereby regulating gas exchange and water loss.

3. **Size of Stomata**: The size of stomata typically ranges from 3 to 12 micrometers in width and 10 to 14 micrometers in length.

4. **Density of Stomata**: The number of stomata can vary significantly, ranging from 1,000 to 60,000 stomata per square centimeter on the leaf surface.

5. **Evaluating Statements**: Now, let's evaluate the provided statements:
- **Statement 1**: "The number of such tiny pores varies from 10 to 60 per centimeter square." This statement is incorrect because the actual range is from 1,000 to 60,000.
- **Statement 2**: "In grasses, the stomatal density is almost the same on both surfaces." This statement is correct as grasses (monocots) have stomata on both the upper and lower surfaces.
- **Statement 3**: "Guard cells are a special type of epidermal cells." This statement is correct.
- **Statement 4**: "The size ranges from 3 to 12 micrometers in width and from 10 to 14 micrometers in length." This statement is also correct.

6. **Conclusion**: The incorrect statement about stomata is the first one, which states that the number of stomata varies from 10 to 60 per centimeter square.

**Final Answer**: The incorrect statement is the first one.

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