Which of the following is true of myelin sheath.

a. It is a lipid or fatty substance

b. In the PNS, is formed by oligodendrocytes

c. In the CNS, is formed by schwann cells

c. a and d only

d. has nodes of ramvier h. in the PNS is foemed by oligodendrocytes

The correct answer will be option-E.

Explanation:

The myelin sheath is the sheath composed of the protein and fats or lipids that covers the axon of the neuron cells. The fatty layer provides the insulation to the neurons which increase the rate of signal transmission through neurons.

The myelin sheath is formed by two different cells in different systems like in central nervous system is formed by the oligonucleotides whereas in the peripheral nervous system by the Schwann cells. The myelin sheath in PNS form gaps in the axon where less or no sheath is present. This gap is known as the "nodes of ranvier".

Thus, option-E is the correct answer.