Plasmolysis is a phenomenon observed in plant cells when they lose water and the cell membrane pulls away from the cell wall. This process typically occurs in a hypertonic solution, where the concentration of solutes outside the cell is higher than inside. As a result, water exits the cell by osmosis, causing the cell’s central vacuole to shrink and the cytoplasm and cell membrane to contract.

Key points about plasmolysis:

1. Hypertonic Environment: Plasmolysis happens when a plant cell is placed in a solution with a higher solute concentration than the cell’s interior, leading to water loss from the cell.
2. Cell Wall and Membrane: The cell wall remains intact during plasmolysis, but the cell membrane detaches from it as the cell contents shrink.
3. Reversibility: Plasmolysis is often reversible if the cell is placed back into an isotonic or hypotonic solution, where the water can re-enter the cell and restore normal turgor pressure.
4. Importance in Plant Physiology: Plasmolysis can affect a plant’s ability to maintain turgor pressure, which is crucial for structural support and overall cell function.

In summary, plasmolysis is an important process in understanding how plant cells respond to osmotic stress and helps illustrate the effects of different solute concentrations on cell integrity.