Answer the following question given this paragraph:   View the University of Michigan WebScope at http://virtualslides. umich. edu/Histology/EMsmallCharts/ 3%20Image%20Scope%20finals/054%20-%20Peripheral%20nerve_001. svs/view. apml?listview=1& (http://openstaxcollege. org/l/nervefiber) to see an electron micrograph of a cross-section of a myelinated nerve fiber. The axon contains microtubules and neurofilaments that are bounded by a plasma membrane known as the axolemma. Outside the plasma membrane of the axon is the myelin sheath, which is composed of the tightly wrapped plasma membrane of a Schwann cell. What aspects of the cells in this image react with the stain to make them a deep, dark, black color, such as the multiple layers that are the myelin sheath?.   Q: The axon contains microtubules and neurofilaments that are bounded by a plasma membrane known as what?   A:
Options:
I. exolemal;
II. axolenon;
III. xerophyte;
IV. axolemma;
IV.