Question

The __________ is the fatty substance that insulates and protects the axon.

Answer 1

the answer you are looking for is the Myelin

Answer 2

Myelin Sheath

Step-by-step explanation:

The Myelin sheath is made of fatty tissue that wraps itself around the axon of the nerves so as to provide protection, insulation and better transmission to the electrical signals across it. The fact that it comprises of fatty substances gives it the properties it needs to provide these functions.