When a plant cell is placed in pure water, it will

Options

A. become rigid because of turgor pressure
B. lose water and wilt
C. swell and burst
D. alter its cell wall composition so that it becomes impermeable to water

Answer

### Step-by-Step Solution:

1. **Understanding the Environment**: When a plant cell is placed in pure water, we need to analyze the concentration of solutes inside the cell compared to the pure water outside.

2. **Identifying the Concentration**: The plant cell contains a higher concentration of solutes compared to pure water, which has no solutes. Therefore, the plant cell is in a hypertonic solution relative to the pure water, which is hypotonic.

3. **Movement of Water**: Water moves from areas of low solute concentration (hypotonic) to areas of high solute concentration (hypertonic). In this case, water will move from the pure water (hypotonic) into the plant cell (hypertonic).

4. **Effect on the Plant Cell**: As water enters the plant cell, it will cause the cell to swell. However, because plant cells have a rigid cell wall, they will not burst. Instead, the cell will become turgid, which means it will become firm and swollen due to the internal pressure from the water.

5. **Conclusion**: The correct answer is that the plant cell will become rigid because of turgor pressure. This pressure is the result of the water entering the cell and pushing against the cell wall.

### Final Answer:
When a plant cell is placed in pure water, it will become rigid because of turgor pressure.

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