Major Dense Lines of a Myelinated Axon

Major dense lines of a myelinated axon

A) represent the fused extracellular surface of the Schwann cell membrane
B) represent the fused cytoplasmic surfaces of the Schwann cell membrane
C) are located at the node of Ranvier
D) are aligned perpendicular to the intraperiod line
E) are absent in myelin sheaths formed by oligodendroglia in the central nervous system