Water balance of cell is maintained by

Options

A. ER
B. vacuoles
C. lysosomes
D. all of these

Answer

**Step-by-Step Solution:**

1. **Understanding Water Balance in Cells:**
- Water balance in cells refers to the regulation of water content within the cell to maintain homeostasis. This is crucial for cellular functions and overall health.

2. **Role of Cell Organelles:**
- Various organelles play a role in maintaining water balance. The endoplasmic reticulum (ER) is involved in the synthesis of proteins and lipids but is not directly responsible for water balance.

3. **Function of Vacuoles:**
- Vacuoles, particularly in plant cells, are essential for maintaining osmotic pressure. They store water and help regulate the cell's internal environment. When a cell is under osmotic stress, vacuoles can absorb water to prevent the cell from collapsing.

4. **Role of Lysosomes:**
- Lysosomes contain digestive enzymes that break down waste materials and cellular debris. While they contribute to cellular maintenance, they do not directly manage water balance.

5. **Conclusion:**
- The primary organelle responsible for maintaining water balance in cells, especially under osmotic stress, is the vacuole. Therefore, the water balance of the cell is maintained by vacuoles.

**Final Answer:**
The water balance of the cell is maintained by vacuoles.

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