The cell wall is a rigid structure that surrounds the cell membrane of plant cells. It provides support and protection for the cell, and it also helps to maintain the cell's shape. The cell wall is made up of cellulose, a type of carbohydrate that is also found in wood and paper.

Cell walls are unique to plant cells. Animal cells do not have cell walls, but they do have a cell membrane. The cell membrane is a thin, flexible layer that surrounds the cell and helps to protect it from its surroundings.