Question

What is the purpose of myelin? Explain how myelin speeds the conduction of the action potential.

Answer 1

Answer:

Myelin is lipid sheath surrounds the neurons. This myelin sheath layers enable fast saltatory conduction of action potential.

The action potential is the impulse generated in neurons in the form of spikes by the synaptic release of neurotransmitter.

Myelin sheath is the lipid covering of the axons, which protect the axon and speed up the process of impulse conduction. Neurons with myelin sheath are called as myelinated neurons and neurons without myelin sheath are called as non-myelinated neurons.

The gap junctions found at regular intervals in the myelin sheath are called as Nodes of Ranvier.   Myelin sheath does not allow the exchange of ions through it and exchange of ions occurs at Nodes of Ranvier only. Myelin sheath helps in the faster conduction of impulses through the axons by saltatory conduction (impulses jump from one node to another).