Final answer:
Microtubules are the cytoskeletal structures that provide tracks for long-distance intracellular transport, using motor proteins to move vesicles and organelles through the cell.
Step-by-step explanation:
The cytoskeletal structure that provides tracks for long-distance intracellular transport is microtubules. These are hollow tubes made from dimers of alpha- and beta-tubulin. They allow motor proteins such as kinesin and dynein to move vesicles and organelles throughout the cell. Microtubules also play a critical role in cell division, serving as tracks along which chromosomes move during mitosis and meiosis. In contrast, intermediate filaments, another type of cytoskeletal fiber, primarily provide structural support and are not involved in intracellular transport. Actin filaments or microfilaments, while important in the maintenance of cell shape and cell motility, especially in muscle contraction, do not serve as tracks for long-distance intracellular transport on the scale that microtubules do.