Plasmolysis in a plant cell is defined as

Options

A. break down (lysis) of plasma membrane in hypotonic medium
B. shrinkage of cytoplasm in hypertonic medium
C. shrinkage of nucleoplasm
D. None of the above

Explanation

**Step-by-Step Solution:**

1. **Understanding Plasmolysis**: Plasmolysis is a phenomenon that occurs in plant cells when they are placed in a hypertonic solution. A hypertonic solution has a higher concentration of solute compared to the inside of the cell.

2. **Cell Structure**: In a typical plant cell, there is a nucleus, cytoplasm, and a cell membrane. The cytoplasm contains a certain concentration of solutes and water.

3. **Effect of Hypertonic Solution**: When a plant cell is placed in a hypertonic solution, the concentration of solute outside the cell is greater than that inside the cell. This means that the water concentration is lower outside the cell.

4. **Osmosis Process**: Osmosis is the movement of water through a semi-permeable membrane from an area of higher water concentration to an area of lower water concentration. In this case, water will move from the inside of the cell (where there is more water) to the outside (where there is less water).

5. **Cell Shrinkage**: As water leaves the cell, the cell begins to shrink. This process is known as exoosmosis, where water exits the cell.

6. **Resulting Condition**: If the cell continues to lose water, it will eventually reach a state where the cell membrane pulls away from the cell wall, resulting in a condition known as a plasmolyzed cell.

7. **Correct Definition**: Therefore, plasmolysis can be defined as the shrinkage of the cytoplasm in a hypertonic medium due to the loss of water from the cell.

8. **Conclusion**: The correct answer to the question "Plasmolysis in a plant cell is defined as" is the "shrinkage of the cytoplasm in a hypertonic medium."

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