A cell swells up when kept in

Options

A. Hypotonic solution
B. Hyperrtonic solution
C. Isotonic solution
D. all of the above

Answer

To determine when a cell swells up, we need to analyze the effects of different types of solutions on the cell. Let's break down the options step by step:

### Step 1: Understand the Types of Solutions
1. **Hypotonic Solution**: This is a solution that has a lower concentration of solute compared to the inside of the cell. It means that the external environment has more water relative to solute.
2. **Hypertonic Solution**: This solution has a higher concentration of solute compared to the inside of the cell. It means that there is less water relative to solute outside the cell.
3. **Isotonic Solution**: In this solution, the concentration of solute is equal inside and outside the cell. There is no net movement of water.

### Step 2: Analyze Water Movement
- **Hypotonic Solution**: When a cell is placed in a hypotonic solution, water moves into the cell because water moves from an area of low solute concentration (hypotonic solution) to an area of high solute concentration (inside the cell). This influx of water causes the cell to swell.

- **Hypertonic Solution**: In a hypertonic solution, water moves out of the cell into the surrounding solution. This causes the cell to lose water and shrink.

- **Isotonic Solution**: In an isotonic solution, there is no net movement of water. The cell remains the same size because the concentration of solute is equal inside and outside.

### Step 3: Conclusion
From the analysis, we can conclude that a cell swells up when kept in a **hypotonic solution**. Therefore, the correct answer is:

**Hypotonic Solution**