At maturity, the cell wall is considered to be dead since it is made up of cellulose and does not possess the characteristics associated with living cells. More specifically, the cellulose provides strength and rigidity to the cell, and does not exhibit any functions associated with living cells such as metabolism, or independent functions. The primary role of the cell wall is to protect and support the internal protoplasm of the cell, and is not able to regulate what moves through and exits the cell such as a cell membrane can.