"The cytoskeleton is the cellular organelle present in the cytoplasm. It is a complex network of structures with varying sizes. Cytoskeleton gives shape to the cell and also provides support to it. The cytoskeleton is also important for cellular movement and also the response of the cell to stimuli. There are three types of cytoskeleton which include: microtubule, intermediate filaments, and microfilaments.
Microtubules are straight, hollow, and tubular. Microtubules are formed by bundles of a globular protein called tubulin. Intermediate filaments are the structures that form a network around the nucleus and extend to the periphery of the cell.
Intermediate filaments are divided into five substances which include: Keratins (in epithelial cells), Glial filaments (in astrocytes), Neurofilaments (in nerve cells), Vimentin (in many types of cells), and Desmin (in muscle fibers). Microfilaments are long and fine thread-like structures with a diameter of about 3 to 6 nm. The microfilaments present in the ectoplasm contain only actin molecules; microfilament provides the cell with resistance against pulling forces."