Question
Biology Question on human nervous system
Which of the following statement is correct for node of Ranvier of nerve
Neurilemma is discontinuous
Myelin sheath is discontinuous
Both neurilemma & Myelin sheath are discontinuous
Covered by myelin sheath
Myelin sheath is discontinuous
Solution
The correct option is (B) : Myelin sheath is discontinuous
Because of the Ranvier nodes, the myelin sheath is disjointed. Nodes of Ranvier, a recurring opening in the myelin sheath that surrounds the axon of certain neurons, help nerve impulses to travel more quickly. A phenomenon called as saltatory conduction allows impulses to move from node to node because nodes of Ranvier periodically interrupt the insulation. The outermost nucleated cytoplasmic layer of Schwann cells, also known as neurolemmocytes, that encircles the neuron's axon is known as the neurolemma.