Describe the ultrastructure of a cilium or flagellum?
The structures of cilia and flagella are basically the same. Eleven microtubules make up each cilium or flagellum. There are two radii in which these microtubules are organized. Nine of them are doublets. The remaining two are solitary microtubules in the center and are located on the perimeter. To create an axial filament, microtubules are encased in a cytoplasmic matrix. Two subunits make up the outer tubules, which are 360 angstroms in diameter. The smaller of these is the A- tubule, which has two arms, and the smaller is the B- tubule.
