Lecture 4

Question 1

where does calcium enter during synaptic transmission

Answer 1

calcium enters the pre synaptic terminal

Question 2

list the 4 stpes of synaptic transmission

Answer 2

1. calcium enters the presynaptic terminal
2. neurotranmitters are released
3. the vesicles containing the neurotransmitters are endocystoed and recycled
4. receptors on the postsynpatic membrane open channels and cause signaling postsynaptically

Question 3

what ion do neurotransmitters need in order to be released

Answer 3

calcium

Question 4

when there is an influx in calcium what happens to membrane potential

Answer 4

there is a change in membrane potential post synaptically

Question 5

how can we indirectly measure the amount of neurotransmitter release

Answer 5

meausing the resulting change in voltage in the post synaptic cel

Question 6

if there is a change in voltage in a post synaptic neuron what is it called

Answer 6

post synaptic membrane potential

Question 7

if the post synaptic cell is a muscle cell and there is a change in membrane potential what is it called

Answer 7

end plate potential

Question 8

define PSP

Answer 8

psp synaptic membrane potential , if there is a change in voltage and the post synaptic cell is a neuron

Question 9

define epp

Answer 9

if the post synaptic cell is a muscle cell and there is a change in voltage

Question 10

t/f lowering the amount of extracellular calcium changes the amount of neurotransmitter release

Answer 10

true

Question 11

what is essential to neurotransmitter release

Answer 11

calcium

Question 12

when we inject calcium do we get an increase or decrease in epp

Answer 12

increase

Question 13

what is a keylator

Answer 13

it binds to calcium to inactivate it

Question 14

what is a neurotransmitter

Answer 14

it is a substance that has an effect on a post synaptic cell

Question 15

are neurotransmitters found in pre or post synaptic cell

Answer 15

presynaptic cell

Question 16

are neurotransmitters released in response to presynaptic depolarization or hyperpolarization

Answer 16

depolarization

Question 17

how do neurotransmitters affect the post synaptic cell

Answer 17

by binding to specific receptors

Question 18

how many types of neurotransmitters are there

Answer 18

2

Question 19

name the 2 types of neurotransmitters

Answer 19

1. small molecule neurotransmitters

2. neuropeptide transmitters

Question 20

how are small molecule neurotransmitters packaged

Answer 20

in small clear core vesicles

Question 21

where are small molecule neurotransmitters synthesized

Answer 21

in the terminal

Question 22

what is the reuptake mechanism for small molecule neurotransmitters

Answer 22

recycled in the terminal

Question 23

how are neuropeptide transmitters packaged

Answer 23

in large dense core vesicles

Question 24

where are neuropeptides synthesized

Answer 24

in the soma

Question 25

what is the reuptake mechansim for neuropeptide transmitters

Answer 25

they degrade after they are released

Question 26

clear core vesicles that are close to the pre synaptic terminal are also known as

Answer 26

readly releasable pool

Question 27

what is the reserve pool

Answer 27

clear core vesicles that are not close ot he the presynaptic membrane

Question 28

what is a co transmitter

Answer 28

a neuron that can release more than one kind of neurotransmitter.

Question 29

what kind of neurotransmitters do co transmitters typically release

Answer 29

small molecule transmitter and neuropeptide transmitter

Question 30

where are calcium channels positioned

Answer 30

close to the presynaptic membrane

Question 31

where is concentration of calcium the highest

Answer 31

clsoe to the pre synaptic membrane

Question 32

where are clear core vesicles only released from

Answer 32

the readly releasable pool

Question 33

what does an influx of calcium trigger

Answer 33

the release of neurotransmitters

Question 34

t/f the principles of synaptic transmission apply whether the post synaptic cells is a muscle or a neuron

Answer 34

true

Question 35

sometimes you see small epps or psp's with out stimultion these mini events are called

Answer 35

mepps or mpsps

Question 36

neurotransmitters come in ________s

Answer 36

packets

Question 37

each packet produces _ _____ sized response

Answer 37

1, MEPP

Question 38

how many packets make up an epp

Answer 38

several

Question 39

what is 4-AP

Answer 39

Voltage gaed potassium channel blocker

Question 40

where does synapsin bind

Answer 40

it reversibly binds to synaptic vesicles

Question 41

what is synapsin a good marker of

Answer 41

pre synaptic terminals

Question 42

which pool is synapsin released from

Answer 42

the reserve pool

Question 43

which pool os CamKII released from

Answer 43

the reserve pool

Question 44

what does CamKII stand for

Answer 44

ca/ calmodulin-dependent protein kinase type 2

Question 45

what is CamKII sensitive to

Answer 45

calcium levels

Question 46

what kind of proteins do fusion use

Answer 46

SNARES

Question 47

where is synaptobrevin found

Answer 47

membrane of the vesicle

Question 48

where is syntaxin , snap 25 found

Answer 48

the plasma membrane

Question 49

what is SNARE involved in

Answer 49

it is involved in the fusion of vesicles to the pre synaptic membrane

Question 50

these 2 proteins help vesicles get close to the plasma membrane

Answer 50

syntaxin and snap 25

Question 51

name the protein that binds to calcium so that it can interact with SNARE and allows vesicles to fuse

Answer 51

synaptotagmin

Question 52

what occurs to the vesicles carrying neurotransmitters after they are released

Answer 52

they are endocytosed and recycled

Question 53

if vesicles fuse to the plasma membrane , what prevents terminals from just getting bigger

Answer 53

synaptic vesicle recycling

Question 54

clathrin plays a role in what function

Answer 54

endocytosis

Question 55

where does clathrin attach and what does it coat

Answer 55

clatherin attaches to the vesicular membrane and coats the budding vesicle

Question 56

the molecular shape of the clathrin physically forces the membrane it binds to into what shape?

Answer 56

into a ball shape

Question 57

what is the role of receptors on the postsynaptic membranes

Answer 57

they open channels and cause signal post synaptically

Question 58

how does neurotransmitter binding to receptors affect the post synaptic cell

Answer 58

neurotransmitter binding generates a response in the post synaptic cell

Question 59

what is end plate current

Answer 59

a response in the post synaptic cell due to a neurotransmitter binding

Question 60

what is post synaptic current

Answer 60

if the postsynaptic cell were another neuron

Question 61

what neurotransmitter does the NMJ use

Answer 61

acetylcholine

Question 62

what isthe post synaptic receptor in the NMJ

Answer 62

acetylichiline receptor

Question 63

what is reversal potential

Answer 63

when there is no net movement of ions

Question 64

can sodium and k calcium go thorugh acetylcholine receptors

Answer 64

yes

Question 65

at the time a muslce is stimulated by acetylcholine is the muscle usually at rest

Answer 65

yes

Question 66

what is the resting membrane potential of a muscle

Answer 66

-90mv

Question 67

acetylcholine receptors are permiable to what 2 ions

Answer 67

sodium and potassium

Question 68

when a cell is at rest , most of the current is due to what ion. (this ion will also depolarize the cell )

Answer 68

sodium

Question 69

are epsp's excitatory or inhibitory

Answer 69

excitatory

Question 70

PSP's that increase the likelihood of firing are ____ because they cause _____

Answer 70

excitatory, depolarization

Question 71

psp's are _____ if they decrease the likelihood of firing, the cell becomes (depolarized/hyperpolarized)

Answer 71

inhibitory, hyperpolarized

Question 72

epsp's result from activating receptors that open channels with a reversal potential that is ______ threshold

Answer 72

over

Question 73

ipsp's result from activating receptors that open channels with a reversal potential that is ______ threshold

Answer 73

below

Question 74

define summation

Answer 74

most neurons recieve many inputs from both excitatory and inhibitory synapses. Neurons sum the PSP's to determine their overall membrane potential

Question 75

define inhibitory input

Answer 75

it will hyperpolarize the membrane potential ( make it more negative )

Question 76

list the 7 steps of synaptic transmission in order

Answer 76

1. neurotransmitter release 2. receptor binding 3. ion channels open or close 4. conductance change causes current flow 5. postsynaptic potential changes 6. post cells excited or inhibited 7. summation determines whether or not an action potential occurs