Question

Myelin reduces membrane capacitance by increasing the thickness of the membrane and thus increasing the separation of cations and anions.
a. True
b. False

Answer 1

Answer: TRUE

Explanation: Myelin is a thick layer of lipoproteins that "wraps" the axons of some nervous cells in a discontinuous form. In electric terms, MYELIN, reduces the membrane capacitance because this layer is to thick to allow the action potential of the entire axon, to depolarize a complete nervous cell.

That is why there are some structures called Ranvier Nodes, those are spaces between every "wrap" of mielina, that have voltage sensitive sodium channels. This space between myelin sheaths, allows a "saltatory nerve conduction", that transmit the electrical impulse from one Ranvier Node to another, becoming the transmition in one of the fastest in the body. If this system would not exist, then the nervous transmision would be very slow.