Isn't it the cell membrane? The cell membrane controls what goes in and out of the cell using active and passive transport. Osmosis being a part of passive transport.
The cell wall is a protective structure that surrounds certain cells, like those in plants and bacteria, helping them withstand high osmotic pressure. It prevents osmotic lysis by providing rigidity and strength, allowing cells to maintain their shape even under stress. This structure is vital for the survival of many organisms in varying environments.
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