As the soil dries out water potential falls towards that in the cell, which continues to lose water to the air. This leads to shrinkage of the cell contents so that turgor pressure is lost and the plant wilts. An equivalent situation occurs when salts accumulate in the soil; one effect of salinity is that cells cannot take up water against the water potential gradient. They cannot grow and may even lose water to their surroundings. Cells in the roots of such plants may show plasmolysis: as the cytoplasm shrinks the plasmamembrane pulls away from the cell wall leaving a fluid-filled space.