Quiz 2 Part 2 : Neurophysiology

Question 1

electrical activity of a cell

Answer 1

neurophysiology

Question 2

two ways neurons communicate

Answer 2

electrical and chemical

Question 3

within a neuron

Answer 3

electrical (neurophysiology)

Question 4

between neurons

Answer 4

chemical (neurochemical)

Question 5

outer layer of the neuron that is a lipid bilayer

Answer 5

cell membrane

Question 6

separates neuron from what it floats in (CSF)

Answer 6

cell membrane

Question 7

the inside of the cell is more _____ than the outside of the cell

Answer 7

negative

Question 8

negatively charged ions

Answer 8

anions

Question 9

positively charged ions

Answer 9

cations

Question 10

ions are dissolved in …

Answer 10

intracellular fluid

Question 11

what is the charge caused by

Answer 11

the difference in ions in the intracellular and extracellular space

Question 12

membrane potential of -60 to -80mV

Answer 12

resting potential

Question 13

when the cells interior has a negative polarity at rest

Answer 13

resting potential

Question 14

proteins that span the cell membrane and allow different types of ions to pass

Answer 14

ion channels

Question 15

channels that are open all the time

Answer 15

leak channels

Question 16

allow only potassium ions to cross freely, restrict the flow of certain ions

Answer 16

selective permeability

Question 17

forces that drive ion movement across the membrane

Answer 17

diffusion and electrostatic pressure

Question 18

diffusion

Answer 18

molecules distribute themselves evenly through a liquid where they are dissolved

Question 19

concentration gradient

Answer 19

ions move from areas of high concentration to areas of low concentration
social distancing for molecules

Question 20

electrostatic pressure

Answer 20

causes ions to flow towards oppositely charged areas

• opposites attract
• like charges repel

Question 21

typical ionic distribution at rest

Answer 21

salty banana

• inside of cell has lots of K+
• outside cell has ions that make up salt Na+ and Cl-
• more Ca2+ outside cell than in
• cover the banana in salt

Question 22

how does K+ move in relation to diffusion

Answer 22

diffusion pushes it out of the cell

Question 23

how does K+ move in relation to electrostatic P

Answer 23

pushes it back into the cell

Question 24

negatively charged proteins (A-)

Answer 24

do not move, stuck inside the membrane always there

Question 25

how does Cl- move in relation to diffusion

Answer 25

moves into the cell

Question 26

how does Cl- move in relation to electrostatic P

Answer 26

pushes it outside of the cell

Question 27

how does Na+ move in relation to diffusion

Answer 27

into the cell

Question 28

how does Na+ move in relation to electrostatic P

Answer 28

into the cell, opposites attract

Question 29

what ion contributes most to keeping neuron at resting potential

Answer 29

K+

Question 30

at rest, why do K+ ions move into the negative interior

Answer 30

electrostatic pressure

Question 31

when does K+ reach equilibrium?

Answer 31

when the movement out is balanced by the movement into the cell

Question 32

why do neurons use a sodium potassium pump?

Answer 32

to maintain resting potential

Question 33

sodium potassium pump

Answer 33

pumps 3 Na+ out of the cell and 2 K+ into the cell | allows ion exchange against concentration gradient

Question 34

brief but large change in membrane potential that originates at the axon hillock

Answer 34

action potential

Question 35

Patterns of action potentials carry information to ___

Answer 35

postsynaptic targets

Question 36

at rest the membrane is __

Answer 36

polarized

Question 37

decrease in membrane potential

Answer 37

depolarization

Question 38

these increase membrane potential

Answer 38

repolarization and hyperpolarization

Question 39

voltage change that spreads passively across membrane, diminishing as it moves away from the point of stimulation

Answer 39

local potentials

Question 40

produces small local depolarization, pushes cell closer to threshold, makes it more likely an action potential will occur

Answer 40

Excitatory Postsynaptic Potential (EPSP)

Question 41

produces small hyperpolarization | - pushes neuron farther away from threshold

Answer 41

Inhibitory Postsynaptic Potential (IPSP)

Question 42

where does the integration between EPSPs and IPSPs

Answer 42

axon hillock

Question 43

neuron fires at full amplitude or none

Answer 43

all or none phenomenon

Question 44

increased frequency =

Answer 44

increased stimulus strength

Question 45

does a louder noise mean there are larger action potentials?

Answer 45

no. it means there are multiple action potentials

Question 46

resting membrane potential

Answer 46

-60 to -80 mV

Question 47

what is/what happens at threshold?

Answer 47

threshold = -55 to -40 mV | the voltage gated Na+ channels open

Question 48

what is/ what happens at the peak of the action potential? | what is this known as?

Answer 48

peak = +40 mV Na channels close, K channels open known as repolarization

Question 49

what is hyperpolarization in mV

Answer 49

below -80mV

Question 50

absolute refractory period

Answer 50

does not matter what stimulus is received, you can not physically have another action potential

Question 51

relative refractory period

Answer 51

difficult to have another action potential, need a really big stimulus to move to an even higher threshold since so low.

Question 52

action potentials are regenerated along the axon at points known as

Answer 52

nodes of ranvier

Question 53

each adjacent section is____ and a new action potential occurs

Answer 53

depolarized

Question 54

the axon potential travels inside the axon and jumps from node to node - travel in one direction

Answer 54

saltatory conduction

Question 55

speed of propagation of action potentials, varies with the diameter of the axon - large diameter = faster speed

Answer 55

conduction velocity

Question 56

what speeds up communication

Answer 56

myelin

Question 57

neurotoxin that blocks voltage gated Na and K ion channels

Answer 57

Tetrodotoxin (TTX)

Question 58

Hw does TTX effect action potential?

Answer 58

prevents depolarization of the action potential, no release of neurotransmitters

Question 59

neurotoxin that is irreversible activator of Na channels, affects nerve and muscle cells, stabilizes open conformation of voltage gated ion channels too much Na adding in, depolarization step then plateau

Answer 59

Batrachotoxin (BTX)