Final answer:
Microtubules originate from the centrosome, specifically from the pair of perpendicularly arranged centrioles that comprise it, a primary feature in animal cells.
Step-by-step explanation:
Microtubules usually originate from the centrosome, which is a microtubule-organizing center found near the nucleus of animal cells. Each centrosome is characterized by a pair of centrioles, two structures that are arranged perpendicularly to each other. These are cylinders composed of nine triplets of microtubules. During cell division, microtubules reorganize to form spindle fibers, and such reorganization occurs at the centrioles in animal cells or at a more amorphous microtubule organizing center (MTOC) in plant cells. Centrioles also play a crucial role in forming cilia and flagella, which are structural elements of the cell composed of microtubules.