EMBRYOLOGY
NERVOUS SYSTEM
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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the spread of action potential down the axon
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along myelinated axons it moves at a speed of about 18-140 meters per second (18-140 mph)
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along unmyelinated axons it moves at a speed of about 1 meter per second (2 mph)
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None of the above
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Detailed explanation-1: -In neuroscience, saltatory conduction (from Latin saltus ‘leap, jump’) is the propagation of action potentials along myelinated axons from one node of Ranvier to the next node, increasing the conduction velocity of action potentials.
Detailed explanation-2: -By acting as an electrical insulator, myelin greatly speeds up action potential conduction (Figure 3.14). For example, whereas unmyelinated axon conduction velocities range from about 0.5 to 10 m/s, myelinated axons can conduct at velocities up to 150 m/s.
Detailed explanation-3: -Summary. Myelin can greatly increase the speed of electrical impulses in neurons because it insulates the axon and assembles voltage-gated sodium channel clusters at discrete nodes along its length.