Impulse speed is faster on myelinated fibers. True.
Explanation:
1. Myelinated fibers are nerve fibers that are covered by a myelin sheath, which is a fatty substance that acts as an insulator.
2. The presence of myelin sheath on nerve fibers allows for faster conduction of electrical impulses along the nerve.
3. The myelin sheath insulates the nerve fiber, preventing the electrical signal from dissipating and increasing the speed of transmission.
4. In contrast, unmyelinated fibers lack this insulating layer, leading to slower conduction of nerve impulses.
5. Therefore, the statement that impulse speed is faster on myelinated fibers is true due to the role of the myelin sheath in enhancing the speed and efficiency of nerve impulse transmission.
