neurophys mst 1 Flashcards
1
Q
glial cells in CNS
A
oligodendrocyte
microglia
astrocyte
ependymal cells
radial glia
2
Q
bipolar neuron
A
has 2 ends
3
Q
classification of neurons depends on what 4 factors
A
morphology
function
location
chemical
4
Q
flow of information in neurones
A
dendrite -> cell body -> axon
5
Q
where does integration occur in a neuron
A
cell body
6
Q
FASTER COMMUNICATION?
axo-dendritic / axo-somatic
A
axo-somatic
7
Q
glial cells in PNS
A
schwann cells & satellite cells
8
Q
satellite cells
A
support cell bodies in PNS
9
Q
schwann cells
A
myelination in PNS
10
Q
astrocytes
A
blood-brain barrier
reuptake of NT
support CNS
bridging between neurons
11
Q
microglia
A
clear up damaged cells
12
Q
ependymal cells
A
create barriers between compartments
source of neural stem cells
13
Q
increase complexity NS does what to
neuron : astrocyte
A
increase in astrocyte : neuron ratio
14
Q
oligodendrocytes
A
arms of myelin to many axons
15
Q
gap junctions on astrocytes
A
connection between astrocytes
(potassium gos through during spatial buffering)
16
Q
blood flow during neuronal activity
A
increased blood flow to areas of neural activity
via. arterial dilation
17
Q
molecules that can cross blood brain barrier
A
small lipid molecules
glucose
18
Q
why do astrocytes release gliotransmitters?
A
regulates synaptic transmission between neurons and ecf in brain
via. d-serine & glutamate excitation
19
Q
threshold
A
potential where passive responses become active ones
20
Q
current
A
movement of charge
21
Q
current depends on
A
- potential difference (V=IR)
- ability to move within substance - conductance G & resistance (G=1/R)
22
Q
capacitance
A
ions interacting across membrane
23
Q
gating
A
opening of channel
24
Q
why is there different forms of channels
A
stimulated by different things
open/close at different rates
allow different amounts of ion to pass
25
voltage gated channels
open and close along an axon vis change in transmembrane voltage
26
ligand gated channels
ion acts as a ligand, binds to receptor
27
mechanically gated channels
sense touch = open
28
how are ion channels selective?
e.g. potassium within selectivity filter is in MOST RELAXED STATE, a different ion in this filter would not be as relaxed
29
major determinant for permeability to an ion
number of channels open
30
what CANT stimulate ion channel to open
increase ion conc outside compared to inside
31
equilibrium
point where conc & elec grads are balanced, no net ion movement
32
fast / slow
(ion channel & gpcr)
ION - fast
GPCR - slow
33
gpcr's
metabotropic
34
amino acid NT's
SMALL
glutamate, gaba, glycine
35
small NT's
Ach, purines, AA's, biogenic amines
36
biogenic amine NT's
dopamine, adrenaline, noradrenaline, serotonin, histamine
37
peptide NT's
what receptor
how many aa's long?
via metabotropic receptors
3-30 AA's long
38
diff between GABA & glutamate
gaba lacks carboxyl group
allowing for receptors to differentiate between
39
viatt
vesicular aa transporter
gaba & glycine have the same
40
transmembrane spanning domain
single AA chain that fits through membrane
41
which NT to Gs
NA
42
which NT to Gq
glutamate
43
which NT to Gi
dopamine
44
what NT's use metabotropic
glutamate, gaba, histamine, A/NA, dopamine, serotonin, purines, Ach
45
dopamine synthesis (mainly)
substantia nigra & ventral tegmental area
46
electric potential
how much current will flow
47
conductance
ability of charge to move from a to b
48
what molecule causes rmp
potassium
49
b4 spectrin & AnKG
(& where is there high density of these?)
link na and k channels to membrane
alot at AIS & nodes
50
Nav isoforms
do different things, expression is diff for diff neurons -> this is plastic
51
myelin protein - MBP
compacts cytoplasm
52
myelin protein MOG &MAG
poke out of ecf, attract next layer
53
nodes
cluster of na channels
high capacitance`
via b4 & ankyrin
54
paranode
ends of nodes
via NFI55 - caspr - contactin
55
juxtaparanode
(& periaxonal space)
K+ channels
periaxonal space: between myelin and axon, transfers substrates between axon and myelin
56
saltatory conduction (myelin)
jump over myelin is not true because ap is intracellular
strength of ap decays at internode & is replenished at node
57
otto loewi & frogs
when heart in one chamber was stimulated, this stimulated heart in attached chamber -> chemical (NT)
58
neurotransmitter criteria
1. produced w/in neuron
2. stored w/in neuron
3. depolarise neuron = release
4. act on receptor after release
5. degradation / reuptake
6. frog heart (same affect when put on post syn)
59
classical NT
(strengths & duration)
fast and short
60
non-classical NT
slow and long
61
post synaptic density
dense b/c alot of protein receptors -> need alot of activation for ap
62
how does Ca2+ = vesicle fusion?
binds to release proteins
63
quantum
how many Ach?
amount of NT in one vesicle
det. min size of post syn potential
(10,000 Ach)
64
miniature end plate potential MEPP
change in membrane potential by single quanta
1/100th of end plate potential
65
co-transmitters
more than one NT released
66
low freq stimulation
clear core vesicles
67
high freq stimulation
large dens vesicles
68
vesicle protein - synapsin
tether vesicles together
69
vesicle protein - clathrin
coating
70
psd-95 protein (post density)
receptors
71
psd pallium
scaffolding (deep layer)
72
how many proteins do excitatory synapses have
1000
73
how many proteins do inhibitory synapses have
250
74
neuroligin/neurexin complex
adhesion between the two neurons (pre and post)
75
neuroligin
post synaptic
76
neurexin
pre synaptic
77
shanks
cytoskeletal proteins
bind homer to metabotropic glutamate receptors & IP3
78
gephrin
inhibitory synapses
hexagonal lattice interacts with inhibitory proteins
79
sensory transduction
convert interaction to change property of neuron to alter firing probability
80
what determines sensory info
type of neuron type NOT stimulus
81
rapidly adapting
transient firing
adapted -> no need to fire
82
slow adapting
fire throughout
83
glabrous skin
hairless skin
84
free nerve endings (glabrous skin)
pain cool heat receptors
85
pacinian corpuscle
vibration detectors
86
ruffini endings & merkel cell
slow adapting
87
meissner corpuscles
rapidly adapting
88
afferent fibres that lack specialisation detect what?
pain
89
muscle spindles
encode length
in parallel
90
golgi tendon organs
encode tension
in series
91
y (gamma) motor neurons
innervate intrafusal muscle fibres
tune static & dynamic responses to 1 prim aff
92
how does olfaction contribute to taste
diffusion of volatile odorants into the nasal cavity
93
granule cells
tuning of olfaction
94
round window
allows fluid to move
95
scala vestibuli (canal)
filled with perolinth
96
scala tympani
filled with endolinth
97
equilibrium potential vs membrane potential
eq: affected by electrochem grad of one cell
mem: affected by gradients of all ions
98
nernst equation
It relates the equilibrium potential of an ion to its intra- and extracellular concentrations.
*calc eq potential*
99
How many connexin subunits form one complete synaptic channel?
12
(6 subunits per connexon, 2*6)
100
connexon
subunit of gap junctions
101
black widow spider venom
promote massive exocytosis
102
active zone
where vesicles fuse on presynpatic
103
how does Ca2+ = NT release?
By binding to and inducing changes in synaptotagmin that cause the plasma membrane to curve
104
Which intracellular component facilitates the processes of endocytosis and exocytosis underlying synaptic communication?
cytoskeleton
(b/c proteins)
105
Which protein plays a key role in endocytosis?
clathrin
106
Which feature of an electrical synapse allows synchronizing the electrical activity of multiple neurons?
Bidirectional transmission of electrical signals
107
How would application of an intracellular Ca 2+ chelator affect the function of a synapse?
It would eliminate the postsynaptic potential and Ca 2+-dependent vesicle fusion.
108
gamma motor neurons
innervate intrafusual muscle fibres (improve accuracy of info)
