Final answer:
The axonal membrane's resistance and capacitance, represented by Rm and Cm, are arranged in parallel, allowing the current to flow through both when possible.
Step-by-step explanation:
The answer to the student's question about the small patch of axonal membrane arrangement is C) Rm; Cm. The Rm represents the membrane resistance, and the Cm represents the membrane capacitance.
These two are arranged in parallel with each other, allowing current to flow through both of them if possible. In myelinated neurons, the action potential occurs at the Nodes of Ranvier because of a clustering of Na+ and K+ ion channels at these nodes.
The myelin sheath, being an insulator, increases the speed of nerve impulse transmission by forcing the action potential to jump from node to node, a process known as saltatory conduction.