Which ions are responsible for stomatal movement according Levitt?

Options

A. `Fe^(2+)`
B. `Zn^(2+)`
C. `K^(+)`
D. `Na^(+)`

Answer

**Step-by-Step Solution:**

1. **Understanding Stomata**: Stomata are small openings on the surfaces of leaves that facilitate gas exchange and transpiration in plants. They play a crucial role in the plant's ability to take in carbon dioxide and release oxygen.

2. **Role of Guard Cells**: Stomata are flanked by guard cells, which control their opening and closing. The movement of ions into and out of these guard cells is essential for stomatal function.

3. **Leavitt's Theory**: According to Leavitt's theory, the movement of potassium ions (K+) into the guard cells is primarily responsible for the opening of stomata. When potassium ions enter the guard cells, they cause the cells to swell, leading to the opening of the stomatal pores.

4. **Additional Ions**: While potassium is the main ion mentioned, other ions such as iron (Fe) can also influence the guard cells' activity. The presence of iron can increase the turgidity of guard cells, further aiding in the opening of stomata.

5. **Conclusion**: Therefore, the ions responsible for stomatal movement according to Leavitt are primarily potassium ions, with iron also playing a supportive role.

**Final Answer**: Potassium ions (K+) are primarily responsible for stomatal movement according to Leavitt, with iron (Fe) also contributing to the process.

---