An organelle found in mature plant cells is a large, fluid-filled central vacuole. The vacuole may occupy more than 75 percent of the plant cell. In the vacuole, the plant stores nutrients as well as toxic wastes. Pressure within the growing vacuole may cause the cell to swell. An organelle called the cytoskeleton is an interconnected system of fibers,threads, and interwoven molecules that give structure to the cell. The main components of the cytoskeleton are microtubules, microfilaments, and intermediate filaments. All are assembled from subunits of proteinl The centriole organelle is a cylinder-like structure that occurs in pairs.Centrioles function in cell division. Many cells have specialized cytoskeletal structures called flagella and cilia. Flagella are long, hairlike organelles that extend from the cell, permitting it to move.