A basal body (also called a basal granule or kinetosome) is an organelle formed from a centriole, and a short cylindrical array of microtubules. It is found at the base of a eukaryotic undulipodium (cilium or flagellum) and serves as a nucleation site for the growth of the axoneme microtubules. Centrioles, from which basal bodies are derived, act as anchoring sites for proteins that in turn anchor micro-tubules within centrosomes, one type of microtubule organizing center (MTOC). These microtubules provide structure and facilitate movement of vesicles and organelles within many eukaryotic cells. Basal bodies, however, are specifically the bases for cilia and flagella that extend out of the cell. Basal bodies are derived from centrioles through a largely mysterious process. They are structurally the same, each containing a microtubule triplet 9*3 helicoidal configuration forming a hollow cylinder. Regulation of basal body production and spatial orientation is a function of the nucleotide-binding domain of γ-tubulin. Flagella are basically attached to the cell membrane from a basal granule.