How does a plant cell wall differ from a cell membrane?

The plant cell wall and the cell membrane are distinct structures with different compositions and functions:

• Structure and Location: The cell membrane (or plasma membrane) is a thin, 4–10 nanometer-thick barrier that surrounds every living cell, delimiting its internal constituents from the external environment. In contrast, the plant cell wall is a specialized, rigid extracellular matrix that surrounds the cell membrane.123
• Composition: The cell wall is primarily composed of cellulose fibers embedded in a matrix of polysaccharides and structural glycoproteins. The cell membrane is a selective barrier that regulates the transport of nutrients and waste products into and out of the cell.41
• Function: While the cell membrane acts as a gatekeeper for molecular transport, the cell wall provides mechanical protection, structural support, and a chemically buffered environment. The cell wall also facilitates the circulation of water and nutrients and serves as a storage site for regulatory molecules. Furthermore, the cell wall provides the necessary resistance against the turgor pressure generated by the cell's internal vacuoles, which is essential for maintaining the rigidity of plant tissues.21563