action potentials and synaptic tranmission Flashcards
1
Q
amplitude
A
peak (not determined by strength)
- specific to neuron
2
Q
strength
A
how frequently they fire
3
Q
active transport
A
move ions against their concentration gradient
4
Q
ion channels
A
- leakage channels
- gated channels
5
Q
gated channel types
A
- voltage gated
- ligand gated
- mechanically gated
6
Q
voltage gated ion channels
A
change in membrane potential causes channel to open
- crucial for generation and conduction of AP
7
Q
ligand gated ion channels
A
chemical stimulus open and closes the channel
- G protein coupled and starts secondary process
8
Q
mechanically gated ion channels
A
forces distort the channel which opens the gate
9
Q
graded potentials
A
- small deviation from resting membrane potential
- can be in either hyper polarize or depolarize
- usually result of ligand gated or mechanically gated ion channels opening or closing
- most common in dendrites and cell bodies of neurons
- amplitude is determined by strength of stimulus
- not all or none
10
Q
absolute refractory period
A
- unable to generate an AP even with a very strong stimulus
- inactivated Na channels cannot reopen
11
Q
relative refractory period
A
- need a suprathreshold stimulus to generate another AP
- voltage gated K+ channels are still open, but Na channels have returned to resting state
12
Q
electrical synapses
A
- ionic current passes directly from one cell to another cell through connexions in gap junctions
- fast
- synchronization
- two way transmission
13
Q
chemical synapses
A
- 2 neurons separated by synaptic cleft
- voltage gated Ca channels open, Ca flows into presynaptic neuron
14
Q
EPSP
A
depolarizes the postsynaptic cell to create an AP
15
Q
IPSP
A
hyper polarizes the postsynaptic cell to inhibit generation of AP
