Myelin speeds up neural transmission along which structures?

• A. Axons
• B. Dendrites
• C. Synapses
• D. Cell Bodies

Answer: (A)

Myelin speeds up nerve signal transmission along axons. The myelin sheath acts as insulation around the axon, increasing membrane resistance and reducing capacitance, so the electrical signal leaks less and travels farther without weakening. The action potential is then regenerated at the nodes of Ranvier, where voltage-gated Na+ channels are concentrated, allowing the impulse to jump from node to node in a process called saltatory conduction. This skipping and regeneration dramatically fast-tracks conduction compared with unmyelinated fibers.

Dendrites and cell bodies are typically not the long, insulated cables that rely on rapid, long-distance conduction, and synapses are the contact points where signals transfer to the next cell rather than pathways for fast propagation along the neuron's length. So the structure that benefits most from myelin for rapid transmission is the axon.