Why A Myelinated Neuron Conducts Impulses Faster?
In a myelinated nerve fiber, the conduction of impulse is faster due to the presence of Myelin sheath and node of Ranvier. As the rate of impulse conduction in a nervous system depends on the diameter of a nerve fiber and the presence or absence of myelin sheath. Neurons with myelin sheath conduct impulse much faster than those without the presence of myelin. Schwann cells (or oligodendrocytes) are located at various regular intervals along the axons of the neuron. Between the areas of myelin are non-myelinated areas present, called as the nodes of Ranvier. Because fat or lipid molecules (myelin) acts as an insulator, a membrane coated with myelin does not conduct an impulse. So, in a myelinated neuron, action potentials occur only along with the nodes and, therefore, impulses jump over the areas of myelin, going from node to node in a process called as saltatory conduction. Action potential velocity Brain cells are also called neurons which ...