Question

Myelin sheath consists of

• A. A layer of cells
• B. Fat
• C. Protein
• D. Alternate fat and protein layers

Answer 1

The correct option is D Alternate fat and protein layers

• Myelin is a lipo-protein layered substance made of phospholipid, cholesterol and protein that covers the axons of the neurons.
  
• It insulates the nerve impulses from the surrounding nerve fibres.
• It also increases the speed of impulses through nerve axons.
• It is formed in the central nervous system by glial cells called the oligodendrocytes.
• Whereas, in the peripheral nervous system they are produced by Schwann cells.
• The myelin sheath is a modified plasma membrane that surrounds the nerve axon in a spiral manner.
• Myelin sheath is made up of alternate lipid and protein layers.
• So, the correct answer is 'Alternate fat and protein layers'.