Eukaryotic cilia and flagella are found on various types of cells, from single-cell protozoa to epithelial cells of multicellular organs. Most have a well-conserved structure called the axoneme, which generates ciliary and flagellar movements. The axoneme is a microtubule-based, highly organized structure composed of more than 250 kinds of proteins. Molecular motors, called the dyneins, exert f...