Sleep movements in Samanea saman are regulated by

Options

A. N
B. P
C. K
D. Mg.

Answer

**Step-by-Step Solution:**

1. **Understanding Sleep Movements:**
- Sleep movements, also known as gnastic movements, are responses of plants to environmental stimuli, particularly touch or vibration.

2. **Identifying the Plant:**
- The plant in question is Samanea saman, commonly known as the rain tree or the shade tree. It is a large tropical tree that can grow up to 60 meters tall and has a broad, umbrella-shaped crown.

3. **Characteristics of Samanea saman:**
- This tree has a rough, wrinkled bark and a symmetrical crown that can extend up to 80 meters wide, making it an attractive choice for shade.

4. **Regulation of Sleep Movements:**
- In Samanea saman, sleep movements are specifically regulated by certain ions. The options provided include Nitrogen, Phosphorus, Potassium, and Magnesium.

5. **Identifying the Correct Ion:**
- After analyzing the options, it is established that the sleep movements in Samanea saman are regulated by potassium ions.

6. **Conclusion:**
- Therefore, the correct answer to the question is Potassium (Option 3).

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