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How does turgor pressure help plant cells become longer and stiffer?

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fern life cycle — Plant development The life cycle of the fern. (1) Clusters (sori) of sporangia (spore cases) grow on the undersurface of mature fern leaves. (2) Released from its spore case, the haploid spore is carried to the ground, where it germinates into a tiny, usually heart-shaped, gametophyte (gamete-producing structure), anchored to the ground by rhizoids (rootlike projections). (3) Under moist conditions, mature sperm are released from the antheridia and swim to the egg-producing archegonia that have formed on the gametophyte's lower surface. (4) When fertilization occurs, a zygote forms and develops into an embryo within the archegonium. (5) The embryo eventually grows larger than the gametophyte and becomes a sporophyte.

In plant development, turgor pressure is the force exerted by fluid within a cell that presses the cell membrane against the cell wall. This process is essential for both cell elongation and structural support.1

Cell Elongation

Plant growth often involves a significant increase in cell volume following cell division. This is primarily achieved through the uptake of water, which is stored in a central vacuole. As the cell takes in water, it generates internal pressure that pushes against the cellulose walls, causing the cell to expand in length and girth.2

Stiffening

Turgor pressure provides the necessary rigidity to living plant tissues that lack thick, permanent secondary cell walls. By filling the vacuoles with water, the cell exerts pressure against the primary cell wall, effectively stiffening the cell in a manner analogous to how air pressure inflates a pneumatic tire. When a plant loses water, this pressure drops, leading to a loss of rigidity and the wilting of leaves and flowers.31