Final answer:
The cell wall is the structure that provides structural strength to the cell, particularly in plant cells, protists, and fungi, and is made predominantly of cellulose.
Step-by-step explanation:
The structure that confers structural strength on the cell is known as the cell wall. In plant cells, the cell wall is the rigid covering that protects the cell, provides structural support, and gives shape to the cell. Fungal and protist cells also possess cell walls. The chief component of the plant cell wall is cellulose, which is a polysaccharide made up of glucose units. This makes the cell walls able to withstand the high internal pressure cells may experience, preventing them from bursting and aiding in maintaining their structural integrity.