Final answer:
Voltage-gated ion channels are responsible for propagating electrical signals in nerve cells, facilitating the action potentials that travel along neuronal axons.
Step-by-step explanation:
The type of ion channel that plays the major role in propagating electrical signals in nerve cells is the voltage-gated ion channel. These channels are critical in the generation and propagation of action potentials along the neuronal axon, enabling the rapid communication necessary for nervous system function.
The process of an action potential involves a sequence where voltage-gated ion channels open and close, resulting in a wave of depolarization that moves along the axon.
This depolarization is essential for the action potential to 'jump' across the nodes of Ranvier in myelinated axons in a process known as saltatory conduction, which accelerates signal transmission.
While ligand-gated ion channels are also important in the nervous system, particularly at synapses where neurotransmitters can open these channels and initiate a change in membrane potential, it is the voltage-gated ion channels that are primarily responsible for the rapid conduction of action potentials down the axon.