Generation of a nerve impulse (C&S) Flashcards
1
Q
Step 1
A
Binding of a neurotransmitter triggers the opening of ligand-gated ion channels at a synapse.
2
Q
Step 2
A
Ion movement occurs and there is
depolarisation of the plasma membrane.
3
Q
Step 3
A
If sufficient ion movement occurs, and the membrane is depolarised beyond a threshold value, the opening of voltage-gated sodium channels is triggered and sodium ions enter the cell down their electrochemical gradient.
4
Q
Step 4
A
This leads to a rapid and large change in the membrane potential.
5
Q
Step 5
A
A short time after opening, the sodium channels become inactivated.
6
Q
Step 6
A
Voltage-gated potassium channels then open to allow potassium ions to move out of the cell to restore the resting membrane potential.