An internal factor in traspiration is

Options

A. `CO_(2)`
B. `O_(2)`
C. `N_(2)`
D. Stomata

Answer

**Step-by-Step Solution:**

1. **Understanding Transpiration**: Transpiration is the process by which water vapor is lost from the plant to the atmosphere, primarily through small openings called stomata. This process also facilitates the exchange of gases, such as carbon dioxide and oxygen.

2. **Identifying Internal Factors**: Internal factors in transpiration refer to elements within the plant that influence the rate of transpiration. These can include the structure and functioning of stomata, guard cells, and the overall health of the plant.

3. **Role of Stomata**: Stomata are small openings on the surface of leaves that regulate gas exchange. They are surrounded by guard cells that control their opening and closing. The number and behavior of stomata directly affect the rate of transpiration.

4. **Evaluating Other Factors**: While carbon dioxide and oxygen are involved in the process, they are not internal factors since they are present in the external environment. The internal factors are more related to the plant's physiological structures.

5. **Conclusion**: The internal factor that significantly influences transpiration is the stomata, specifically their number and the ability of guard cells to open and close them. More stomata lead to increased transpiration, while fewer stomata can hinder it.

**Final Answer**: An internal factor in transpiration is the stomata.

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