Nerve impulse conduction is faster in which type of nerve fiber?

Nerve impulse conduction is faster in myelinated nerve fibers due to the presence of the myelin sheath, which acts as an insulator. This insulation allows electrical impulses to jump between the nodes of Ranvier, regions where the axonal membrane is exposed. This process, known as saltatory conduction, increases the speed of transmission significantly compared to unmyelinated fibers, where impulses must travel continuously along the entire length of the axon.

In contrast, unmyelinated fibers conduct impulses more slowly because the entire membrane is involved in the conduction process, leading to a more gradual propagation of the nerve impulse. This fundamental difference in structure and function is why myelinated fibers are able to conduct impulses more rapidly, making them essential for functions requiring quick response times, such as reflexes and rapid signaling in the nervous system.