Question

How does the presence of Myelin affect an action potential?

a. Current flows along the unmyelinated segments and action potentials propagate along the myelinated portions of the axon, decreasing the speed and efficiency of the action potential.

b. Current flows under the myelin segments and action potentials propagate along the unmyelinated segments of the axon, decreasing the speed and efficiency of the action potential.

c. Current flows under the unmyelinated segments and action potentials propagate along the myelinated portions of the axon, increasing the speed and efficiency of the action potential.

d. Current flows under the myelin and action potentials propagate along the unmyelinated segments of the axon, increasing the speed and efficiency of the action potential.

Answer 1

I can't help with this one but @ganeshie8 @TuringTest @iambatman @myininaya

Answer 2

@Preetha

Answer 3

@I_Always_Smiling

Answer 4

INTERNET SOURCE

Myelin sheath does several things that affect the speed of an action potential.

It acts as an insulator around a neuron axon, thereby focusing the propagation of the action potential along the axis of the axon.

The action potential "leaps" from one node of Ranvier (the node in between two myelinated segments) to the next, and to the next, and to the next, and so on, faster than the action potential can propagate as a wave along an unmyelinated axon of the same diameter.

The regions along a myelinated axon depolarize locally and successively, thus allowing an action potential to travel along an axon using less energy, which in turn allows the neuron to repolarize more quickly, and thus be ready to conduct the next action potential sooner, thereby increasing the overall speed of information transmission.

Answer 5

but i'm currently reading this which seems interesting enough

http://forums.studentdoctor.net/threads/how-does-myelin-sheath-increase-nerve-impulse-speed.755932/

Answer 6

Hmmm.. So, I'm thinking D?

Answer 7

well basically the presence of myelin and the diameter of the axon affect the speed of an action potential

Answer 8

Okay. I think I got it. Thanks for the source!

Answer 9

seeing as the crossing over of ions (over the cell membrane) only ever occurs at the nodes of Ranvier thenone could say that the action potential will augment due to the impulses being able to transfer themselves between nodes rather than being forced to travel down the axon itself.

Answer 10

hope i helped :)

Answer 11

have a totally epic day :)

Answer 12

Don't forget to close this question :)