Final answer:
The gaps between neurolemmocytes along an axon are called nodes of Ranvier. These nodes play an essential role in the rapid transmission of nerve impulses by allowing action potentials to jump from node to node.
Step-by-step explanation:
Along an axon, the gaps between neurolemmocytes are called nodes of Ranvier. These nodes are critical for the rapid transmission of nerve impulses. As the impulse travels along the axon, it jumps from one node to the next in a process called saltatory conduction, vastly increasing the speed at which the impulses travel. Nerve impulses are able to skip from one node to the next because action potentials occur at these gaps. The axon segments between the nodes are wrapped in a substance called myelin, which is produced by glial cells known as Schwann cells in the peripheral nervous system and oligodendrocytes in the central nervous system, acting as an electrical insulator.