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How does water entering a plant cell vacuole create turgor pressure?

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Cutaway illustration of a plant cell showing labeled internal structures including the nucleus, nucleolus, chloroplast, mitochondrion, vacuole, endoplasmic reticulum, ribosomes, Golgi apparatus, cell wall, and other key organelles. — Cell wall Cutaway drawing of a plant cell, showing the cell wall and internal organelles.

In plant cells, the vacuole maintains a high concentration of solutes, such as salts and sugars, within its cell sap. This high concentration drives the entry of water into the vacuole through osmosis.1

As water enters, the vacuole expands and generates hydrostatic pressure, known as turgor pressure. This pressure forces the cell membrane outward, pressing it firmly against the rigid cell wall.12

This process is essential for the structural integrity of the plant; the resulting turgor-induced stiffening of the cell walls provides the necessary support for non-woody plant tissues, much like air pressure stiffens a pneumatic tire. When a plant loses water, this pressure drops, leading to the loss of rigidity and the wilting of leaves and flowers.32