Solve this:
Q.171. The given nervous system figure illustrate the axonal membrane and propagation of nerve impulse what will be the direction of propagation of nerve impulse:-

(1) X  Y
(2) Y  X
(3) Z  Y
(4) Y  Z

Dear Student,
As signal triggers from another neuron, sodium/potassium channels open and close as the membrane reaches its threshold potential. As nerve impulse travels down the axon, there is a change in polarity across axonal membrane. 

At the start of action potential, sodium channels open and Na+ moves into axon causing de-polarisation. Re-polarisation occurs when K+ channels open and K+ moves out of axon. Thus, there is a change in polarity across axonal membrane. 

So, as given in picture in question, nerve impulse propagate from X to Y and then Y to Z. Option (1) and (4) are correct answers. 


  • 0
What are you looking for?