Halophytes can grow on physiologically dry soil due to presence of

Options

A. exccess salts in water
B. excess salts in plants
C. excess humidity outside
D. thin leaves

Answer

**Step-by-Step Solution:**

1. **Understanding Halophytes**: Halophytes are specialized plants that thrive in saline environments, such as coastal areas or salt marshes. They have adapted to survive in conditions where the soil has high salt content.

2. **Physiological Adaptation**: The key to their survival in physiologically dry soil is their ability to manage salt concentrations. Halophytes possess mechanisms that allow them to tolerate high levels of salt.

3. **Role of Vacuoles**: In halophytes, the root hair cells contain large central vacuoles that store high concentrations of salt. This adaptation helps them maintain osmotic balance.

4. **Hypertonic Solution**: The high salt concentration inside the vacuoles makes the root hair cells hypertonic compared to the surrounding soil. This difference in concentration is crucial for water uptake.

5. **Water Movement**: Due to osmosis, water from the soil moves into the root hair cells. The process occurs because the concentration of water is higher outside the cell (in the soil) than inside (where there is more salt).

6. **Conclusion**: Therefore, halophytes can grow in physiologically dry soil due to the presence of high salt concentrations in their vacuoles, which allows them to draw in water from the surrounding environment.

---