hollow tubes of tubulin proteins

-> maintain the shape of the cells during mitosis by forming spindle fibers to help separate the chromosomes
-> form a pair of structures known as centrioles, which is located near the nucleus of animal cells to help organize cell division
-> build projections, or cilia and flagella from the cell surface to enable cells to move through liquids

Microtubules

threadlike structure of actin proteins

-> form extensive networks and produce a tough, flexible framework for structural support
-> its assembly and disassembly helps the cytoplasmic movement of cells

Microfilaments