Question

Which one of the following describes saltatory conduction ?

• A. Faster than conduction on an unmyelinated fiber
• B. Occurs only if nodes of Ranvier are lacking
• C. Occurs only if the myelin sheath is continuous
• D. Slower than conduction on an unmyelinated fiber

Answer 1

The correct option is A

Faster than conduction on an unmyelinated fiber

Saltatory conduction is the propagation of action potentials along myelinated axons. Here the signal jumps from one node of Ranvier to the next node, increasing the conduction velocity of action potentials. The uninsulated nodes of Ranvier are the only places along the axon where membrane depolarization and ion exchange occurs across the axon membrane. On the contrary, in an unmyelinated neuron, the signal is transmitted from one neuronal segment to another as depolarization and repolarization, making the process a lot slower.