Transmission of Action potential

Generation and Transmission of Action potential

What is an action potential 

An action potential is the wave of depolasiration of the membrane of a neurone when the inside becomes more negative than the outside; its value is about +40mV

When a nerve cell wants to transmit messages from one part of the cell to another, the messages are usually transmitted in form of an action potential 

So, a never cell must be able to GENERATE an action potential and it must be able to TRANSMIT the action potential 

Action potential can move from one part of the nerve cell to another part. 
Action potential can move from one nerve cell to another nerve cell 

(note that nerve cell is the same thing as neurone; and it is the basic structural and functional unit of the nervous system)

Before an action potential can be generated, two important things must be in place 

• The nerve cell must be at rest. i.e. it must have RESTING MEMBRANE POTENTIAL VALUE OF -70mV

• There must be a stimulus that exceeds the THRESHOLD VALUE 

Generator potential and Threshold potential 

Threshold potential is the potential difference that must be met or exceeded if a nervous impulse will be generated by a neurone; its value is -40mV 

Generator potential is the depolarization of a neurone that occurs as a result of a small stimuli and does not lead to the generation of an action potential