Internodal segment
Encyclopedia
An internodal segment is the portion of a nerve fiber
between two Nodes of Ranvier
. The neurolemma
or primitive sheath is not interrupted at the nodes, but passes over them as a continuous membrane.
Nerve fiber
A nerve fiber is a threadlike extension of a nerve cell and consists of an axon and myelin sheath in the nervous system. There are nerve fibers in the central nervous system and peripheral nervous system. A nerve fiber may be myelinated and/or unmyelinated. In the central nervous system , myelin...
between two Nodes of Ranvier
Nodes of Ranvier
Myelin sheath gaps or nodes of Ranvier are the gaps formed between the myelin sheaths generated by different cells. A myelin sheath is a many-layered coating, largely composed of a fatty substance called myelin, that wraps around the axon of a neuron and very efficiently insulates it...
. The neurolemma
Neurolemma
Neurolemma is the outermost nucleated cytoplasmic layer of Schwann cells that surrounds the axon of the neuron. It forms the outermost layer of the nerve fiber in the peripheral nervous system....
or primitive sheath is not interrupted at the nodes, but passes over them as a continuous membrane.