Node of Ranvier means
- Nodes of Ranvier or Myelin sheath gaps, are the gaps (approximately 1 micrometer in length) formed between the myelin sheaths generated by different cells. O 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. O At nodes of Ranvier, the axonal membrane is uninsulated and therefore capable of generating electrical activity. O Since fat serves as a good insulator, the myelin sheaths speed the rate of transmission of an electrical impulse along the axon. O Electrical impulse jumps from one node to the next at a rate as fast as 120 meters/ second. O This rapid rate of conduction is called salutatory conduction. O Myelinated axons are rare in the autonomic nervous system. Inveebrates do not have myelinated sheaths.