when you look at the cord coming out of the lamp on your desk, you will notice that there is a protective coating that surrounds and encapsulates the electricity-conducting wire inside. if you were to relate that model to the human neuron, the protective coating would refer to the

Myelin

Explanation:

Myelin is a fatty substance that surrounds nerve cell axons to insulate them and increase the rate at which information is passed along. The myelin can be compared to the protective coating of an electrical wire.

i’m   sure probably just geuss and see which one you can get right, i’m pretty sure it is the combination of goods and services