Water flows into the cell and out of the cell and are in equilibrium too when the cells are placed in

Options

A. Hypertonic solution
B. Isotonic solution
C. Hypotonic solution
D. Pure water

Answer

To determine the condition in which water flows into and out of the cell at equilibrium, we need to analyze the different types of solutions in which a cell can be placed.

### Step-by-Step Solution:

1. **Understanding the Types of Solutions:**
- **Hypertonic Solution:** This solution has a higher concentration of solutes compared to the inside of the cell. When a cell is placed in a hypertonic solution, water moves out of the cell to balance the concentration, causing the cell to shrink.
- **Hypotonic Solution:** This solution has a lower concentration of solutes compared to the inside of the cell. When a cell is placed in a hypotonic solution, water moves into the cell, leading to swelling and potentially bursting (lysis) of the cell.
- **Isotonic Solution:** This solution has an equal concentration of solutes compared to the inside of the cell. In this case, water moves in and out of the cell at equal rates, maintaining equilibrium.

2. **Analyzing the Question:**
- The question states that water flows into the cell and out of the cell and are in equilibrium. This indicates that there is no net movement of water in one direction, which is characteristic of an isotonic environment.

3. **Conclusion:**
- Based on the analysis, the correct answer is that the cell is placed in an **isotonic solution**. In this solution, water flows in and out of the cell at equal rates, maintaining equilibrium.

### Final Answer:
The cell is placed in an **isotonic solution**.

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