Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

NRSC 2000 > Electrical Properties > Flashcards

Electrical Properties Flashcards

1
Q

What are the three types of neuronal electrical signals?

A

receptor potential, synaptic potential, action potential

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the differences between receptor, synaptic, and action potentials in how they are produced?

A

receptor is when receptor is stimulated (ie, skin), synaptic is when synapse is stimulated, action is when neuron is stimulate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Order the neuronal electrical signals from fastest to slowest?

A

action, synaptic, receptor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Membrane potential changes is correlation to what?

A

current flow (mV)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Does the shape/amplitude of action potentials change when the current is increased?

A

no the frequency does

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What does all or nothing mean in terms of action potentials?

A

once threshold is passed will produce a unifrom response, if not et than no response

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is a graded potential?

A

typically produced by sensory neurons or neurotransmitter activity

small change in membrane potential that is proportional to size/intensity of stimulus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Electrochemical equilibrium is the balance between what forces?

A

chemical driving force (concentration gradient)

electrical driving force (potential difference)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the effects of chemica/electrical driving force on the movement of K+?

A

chemical: conc gradient causes K+ to efflux

electrical: electrical potential diff causes K+ to influx

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the function of the Nernst equation?

A

calculating equilibrium potential (voltage where there is no net movement of any ion)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the difference between active transporters and ion channels?

A

active: require energy, create conc. gradients, move ions against gradient

channel: allows ions to diffuse down conc. gradient, only allow certain ions to diffuse

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What does the goldman equation calcualte?

A

considers multiple ions and their permeability, calculates membrane potential

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What does the Na+/K+ pump do?

A

sends 2 K+ into the cell and brings 3 Na+ out of cell (net loss of posititve charge inside the cell)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What does the graph of a receptor potential look like?

A

big initial spike that drops off and then slowly decreases, fully goes back after stimulation stops

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What does the graph of a synaptic potential look like?

A

big initial spike and then slow decrease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What does hyperpolarization mean?

A

becoming more negative

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What does depolarization mean?

A

becoming less negative

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What happens when you inject a posititve current?

A

depolarizes (can lead to action potential

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

After you stop injecting the current what will happen?

A

the membrane potential will return to normal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What happens over distance to electrical signals?

A

they decay

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Why is Ca2+ a good ion for signalling?

A

very low concentration inside the cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Is the concentration of sodium greater inside or outside the cell?

A

10x greater outisde

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Is the concentration of potassium greater inside or outside of the cell?

A

20x greater inside

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What are leaky channels?

A

some non-gated potassium channels in the membrane allow a slow facilitated diffusion K+ out of the cell, help maintain membrane potential

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What does [K]o mean vs [K]e?

A

potassium conc. outisde vs potassium conc, inside

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

The inside-negative resting potential arises because?

A

the membrane of a resting neuron is more permeable to K+ than any other ion, there is more K+ insde than outside

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What ion is the membrane of a neuron more permeable to when resting? Why?

A

K+, more channels are open for potassium when resting

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What ion is the membrane more permeable to during an action potential?

A

Na+, increase in permeability of sodium results in the depolarization part of action potential

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What determines the resting potential of giant squid axon?

A

concentration of potassium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

How does a greater conc. of K+ affect the resting membrane potential of squid axon?

A

increasing the conc. makes the resting potential more positive

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What happens to action potentials in a giant squid axon when there is a low [Na]? Once [Na] is brought back to normal what happens?

A

the increase is not as steep and the amplitude is decreased

it recovers and goes back to making normal action potentials

32
Q

What is the major difference between the ion concentrations of a mammalian neuron and a squid neuron?

A

the numbers are bigger in the squid neuron, so like its 30 instead of 5 for example

33
Q

How does hyperpolarization of membrane potential affect membrane current?

A

inward current (capacititve current)

34
Q

How does depolarization of membrane potential affect membrane current?

A

outward current, then transient inward current then delayed outward current

35
Q

What is the early current dependent on?

A

sodium concentration (early current is inward when sodium is present, outward when not)

36
Q

What is the delayed current depednet on?

A

potassium concentration (will stay flat if no K+, will go up if K+)

37
Q

How is depolarization related to conductance of Na+ and K+?

A

depolarization increases the conductance on these ions

38
Q

What is the fast positive cycle?

A

depolarize membrane potential, open Na+ channels, increase Na+ current, leads to depolarization

39
Q

What is the slow negative cycle?

A

depolarize membrane potential, open K+ channels, increase K+ current, leads to hyperpolarization

40
Q

How does action potential conduction use passive current flow?

A

it passively flows down the axon which causes other channels to open, propogating the action potential

41
Q

What is paranode?

A

part of axon right before the node of ranvier, covered by the end of myelin

42
Q

What is saltatory conduction?

A

electrical impulse jumps from ndoe to node, faster, requires myelinated axons

43
Q

What does puffer fish poison do?

A

tetradoxin disrupts Na+ channels

44
Q

What does charcot marie tooth cause?

A

damage to myelin in peripheral nerves, causes issues with muscles, walking, weakness

45
Q

What are the two types of CMT talked about in class?

A

1a and X

46
Q

What are the two disorders of myelin discussed in class?

A

charcot-marie-tooth (peripheral) and multiple sclerosis (central)

47
Q

What is the voltage clamp method used for?

A

to measure the ion currents through membranes of excitable cells whilst holding the membrane voltage at a set level

48
Q

What are the types of patch clamp methods?

A

cell attached recording, whole cell recording, inside out recording, outside out recording

49
Q

How does cell attached recording work?

A

recording pipette contacts the membrane and applys mild suction

50
Q

How does whole cell recording work?

A

recodring pipette apply strong suction pulse, makes it so the cytoplasm is continuous with pieptte interior

51
Q

How does inside out recording work?

A

pipette applies soft suction out a channel, and is pulled back to tear the membrane, exposed to bath solution that mimics cell conditions, acts on inside of channel

52
Q

How does outside out recording work?

A

pipette applies strong suction and its ripped back, membrane ends anneal so outside of channel is availbe

53
Q

What is rapid inactivation in regards to channels? What type of channels use this?

A

when channel is open there is a flap that closes it because it takes longer for the entire channel to close

voltage gated channels

54
Q

How do voltage gated channels work?

A

they open/close in response to the changes in membrane voltage, use voltage sensors

54
Q

What does scorpion toxin affect?

A

Na+ channels, reduces effectiveness

55
Q

How do ligand gated channels work?

A

neurotransmitters, other ions, or cyclic nucletides bind to channels to open/close them

56
Q

What is the ball and chain model?

A

ball attached to channel (ie. amino acid), that switches it to inactive before it finishes closing

57
Q

What is the selectivity filter?

A

channels have different sized pores that differnt ions couldn’t fit through, acts as a filter

58
Q

What are some site 1 blocker?

A

tetrodotoxin, saxitoxin

59
Q

What are some site 2 blockers?

A

batrachotoxins, grayanotoxins

60
Q

What are some site 3 blockers?

A

scorpion-alpha toxin, sea anemone toxin

61
Q

What are some site 4 blockers?

A

scorpion/spider beta toxins

62
Q

What are some site 5 blockers?

A

brevetoxins, ciguatoxins

63
Q

How many subunits are in potassium channels?

A

4

64
Q

What are some types of K+ voltage gated channels?

A

Kv and HERG, inward rectifier, Ca2+ activated, 2-P

65
Q

What part of a bacterial K+ channel senses voltage changes?

A

negatively charged pore helix

66
Q

What is GEFS+?

A

genetic epilepsy with fibrile seizures plus, autosomal dominant disorder usually caused by mutations in SCN1A (a voltage-gated sodium channel).

67
Q

What is myotonia?

A

neuromuscular condition in which
the relaxation of a muscle is impaired.

68
Q

What is episodic ataxia 1?

A

EA1, potassium channelopathy
characterized by constant myokymia and dramatic episodes of
spastic contractions of the skeletal muscles of the head, arms,
and legs with loss of both motor coordination and balance.

69
Q

What is BFNS?

A

autosomal
dominant inherited form of seizures. It manifests in newborns, tonic clonic

70
Q

What is episodic ataxia 2?

A

EA2, calcium channelopathy caused by a mutation in CACNA1A. Spells are characterized by ataxia, which may
be accompanied by vertigo, diplopia, dysarthria, and generalized weakness, constant nystagmus

71
Q

What is CSNB?

A

congenital stationary night blindness, heterogenous collection of rare genetic diseases affecting photoreceptors, non-progressive dark or dim-light visual
difficulties from birth

72
Q

What is chloride channel myotonia?

A

genetic disease, caused by a fault on the CLCN1 gene, which produces a protein that controls the amount of chloride flowing in and out of the muscle cells

73
Q

What are some symptoms of myotonia?

A

intellectual impairment, cataracts, retinal damage, sleep apnea, weakness, atrophy

74
Q

How do ATPase pumps work?

A

they use atp in order to transport ions

75
Q

How do ion exchangers work?

A

more than 1 ion is exchanged for each other

76
Q

How do cotransporters work?

A

co transport 2 or more ions/neurotransmitters in the same or opposite directions

NRSC 2000 (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions