Cilia and flagella

Cilia and flagella are hair-like structures on the surface of cells that help with movement. Cilia are short and numerous, resembling tiny oars that move in a coordinated manner, while flagella are longer and usually occur singly or in pairs, like a whip. Both are composed of a protein called tubulin and have similar internal structures. Cilia can help cells move through fluids or move fluids over the cell surface, while flagella typically propel the entire cell, as seen in sperm. Both play important roles in biology, from locomotion to clearing mucus in respiratory systems.