The ion which shows active influx into guard cells during day time in a photoactive stomata

Options

A. Chlorine
B. Potassium
C. Malate
D. Calcium

Answer

**Step-by-Step Solution:**

1. **Understanding Guard Cells and Stomata**:
- Guard cells are specialized cells that surround the stomata (pores) on the leaf surface. They regulate the opening and closing of these stomata, which is crucial for gas exchange and transpiration in plants.

2. **Identifying Active Influx**:
- Active influx refers to the movement of ions into the guard cells against their concentration gradient, which requires energy. This process is essential for the functioning of guard cells during the day.

3. **Role of Ions in Guard Cells**:
- During the daytime, when photosynthesis occurs, guard cells take up certain ions to facilitate the opening of stomata. The influx of specific ions causes water to enter the guard cells, leading to turgor pressure that opens the stomata.

4. **Determining the Ion**:
- Among the ions listed (chloride, potassium, malate, calcium), we need to identify which one shows active influx into guard cells during the daytime.
- Potassium ions (K+) are known to be actively transported into guard cells during daylight. This influx of potassium leads to an increase in osmotic pressure, causing water to enter the cells and resulting in the opening of the stomata.

5. **Conclusion**:
- The ion that shows active influx into guard cells during the daytime in photoactive stomata is **potassium (K+)**.

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