The plant cell wall's primary function in osmosis is to provide structural support and prevent the cell from bursting due to the influx of water.
Here's a more detailed explanation:
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Osmosis and Turgor Pressure: When a plant cell is in a hypotonic environment (an environment where the water concentration is higher outside the cell than inside), water moves into the cell via osmosis. This influx of water increases the pressure inside the cell, known as turgor pressure.
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Cell Wall's Role: The cell wall, a rigid structure located outside the cell membrane, counteracts this turgor pressure. While fully permeable to water and small solutes, it provides a defined shape to the cell and resists the expansion caused by water uptake.
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Preventing Lysis: Without the cell wall, the excessive influx of water would cause the cell membrane to rupture, a process called lysis. The cell wall prevents lysis by withstanding the turgor pressure.
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Maintaining Turgidity: The cell wall allows the plant cell to become turgid, meaning swollen with water. Turgidity is essential for maintaining the rigidity of plant tissues, which is necessary for supporting the plant's structure (e.g., stems, leaves).
In summary, the plant cell wall allows water to enter the cell via osmosis, maintains turgor pressure for structural support, and importantly, prevents the cell from bursting.
