Nervous System Flashcards
1
Q
How many Na+ are pumped out per K+ pumped in at resting potential?
A
3 Na+
2 K+
2
Q
What happens during an action potential?
A
depolarization (Na+ rushing in) followed by repolarization (K+ rushing out) along the nerve axon
3
Q
What happens in a synapse?
A
- at synaptic knob, voltage gated Ca 2+ channels open sending Ca 2+ into the cell
- vesicles fuse with presynaptic membrane sending the neurotransmitter across the synaptic cleft
- neurotransmitter binds to receptors on the postsynaptic membrane, triggering depolarization
4
Q
4 steps of action potential?
A
- resting
- depolarization
- repolarization
- hyperpolarization
5
Q
What is going on at rest?
A
all gates closed
6
Q
Depolarization?
A
Na+ gates open, rush in
7
Q
Repolarization?
A
Na+ gates inactivate, K+ gates open
8
Q
Hyperpolarization?
A
all gates closed
