Impulse generation Flashcards
If we measure the voltage of resting neuron using a voltmeter we will see reading of…
-65 mV
What is the ion distribution of a neuron at REST??
- NA+ outside the neuron
- K+ And large negatively charged organic molecules inside the neuron
When sodium gates open it allows…
It allows some NA+ to enter the Axoplasm (interior), making the inside more positive than the outside by 40 mV
The opening of sodium gates in one area causes….
Sodium gates in the next area to open. This causes a wave motion or chain reaction moving down the nerve fibres
After the sodium gates have opened…
Then potassium gates open….K+ exits the axoplasm
After repolarization charge is back to normal but…
Ions are reversed
There is a difference in _____________________ on either side of the membrane of a neuron
Ion distribution
But happens when the axon or a dendrite is stimulated?
Sodium gates open
What machine allows us to see a change in voltage over aperiod of time?
A machine called a oscilloscope… when hooked up to our voltmeter
What happens when the neuron is stimulated?
The charge changes briefly to +40 mV then back to -65 mV
Nerve impulses are known as…..
Electrical messages
down swing phase
When the potassium gates open, k+ exits the axoplasm
Depolarization
When the charge changes from -65 mV to 40 mV
When sodium potassium pump returns NA+ to the outside and K+ to the inside
Recovery phase
During the downswing phase when the charge returns to -65, the change is called ________
Repolarization
