synpase & neurotransmitters

Question 0

pre-synaptic neuron

Answer 0

axon

Question 1

contact between a neuron and another neuron or its effector cell

Answer 1

synapse

Question 2

post-synaptic neuron

Answer 2

dendrite or cell body

OR

cell (ex: muscle)

Question 3

cells are separated by what in synpases

Answer 3

synaptic cleft

Question 4

the predominant type of synapses

Answer 4

chemical synapses

Question 5

chemical synapses is __directional

Answer 5

unidirectional

Question 6

true or false. chemical synapses uses neurotransmitters

Answer 6

true

Question 7

the properties of a chemical synapse scan be changed by the ____ of a neuron

Answer 7

metabolism

Question 8

4 criteria of a neurotransmitter (NT)

Answer 8

1. must be present in pre-synaptic terminal
2. released upon stimulation
3. NT in extracellular fluid must yield same response as synaptic event
4. a removal mechanism must exist

Question 9

NT active for short period of time b/c of what 3 things

Answer 9

enzymatic destruction
re-uptake
extracellular peptidase digestion

Question 10

directly alter membrane permeability….ionotropic or metabotropic

Answer 10

ionotropic

Question 11

ionotropic/metabotropic…..which is slow and which is fast

Answer 11

ionotropic = fast
metabotropic = slow

Question 12

produces a metabolic change in post-synaptic cell….ionotrpoic or metabotropic

Answer 12

metabotropic

Question 13

basic overview of chemical synapses

Answer 13

• NT released into synaptic cleft

- binds receptor on post-synaptic effector & alters post-synaptic cell function

Question 14

where is the NT synthesized

Answer 14

pre-synaptic cell

Question 15

NT requires what 2 things

Answer 15

• membrane depolarization

- calcium influx

Question 16

NT release involves what type of channels

Answer 16

voltage-gated calcium channels

Question 17

Ca2+ influx into cytosol triggers what

Answer 17

exocytosis of vescicles

- vesicles fuse to plasma membrane 
- NT released into synaptic cleft

Question 18

ligand gated channels (4 characteristics)

Answer 18

1. synaptic transmission
2. permeability depends on NT binding
3. located on cell body and dendrites
4. potentials are graded & spread decrementally

Question 19

voltage-gated channels (4 characteristics)

Answer 19

1. action potential generation
2. NT release
3. permeability dependent on M.P.
4. potentials are “all or nothing” and propagated

Question 20

synaptic potentials occur in ____

Answer 20

ionotropic synapses

Question 21

inhibitory vs. excitory

Answer 21

inhibitory: hyperpolarizes (makes more than resting)
excitory: depolarizes (makes less than resting)

Question 22

single nerve stimulated in rapid succession

Answer 22

temporal summation

Question 23

several pre-synaptic neurons acting on same post-synaptic neuron stimulated simultaneously

Answer 23

spatial summation

Question 24

whether or not an action potential is generated depends on:

Answer 24

1. spatial or temporal summation | 2. proximity of synapse to axon hillock

Question 25

further from axon hillock, ____ PSP is degraded

Answer 25

more

Question 26

synapse within cell body = closer to hillock = more influence

Answer 26

axosomatic

Question 27

synapse with dendrite = farther from hillock = less influence

Answer 27

axodendritic

Question 28

sum of all ion currents flowing through channels at once

Answer 28

synaptic current

Question 29

4 properties of a fast ionotropic receptor

Answer 29

1. channel opening is all or nothing 2. channel opening depends on NT concentration (more NT=more opening) 3. current flowing through channels contributes to neuron's PSP 4. currents through all channels can be summated (can add to each other or cancel each other out)

Question 30

synpase between neuron & skeletal muscle fiber

Answer 30

neuromuscular EPSP

Question 31

each motor neuron action potential causes a large EPSP in the muscle

Answer 31

relay synapse

Question 32

a NT that: - binds to a ligand-gated Na+/K+ membrane channel - increases membrane permeability to Na+ and K+ - depolarizes membrane - makes Na+ flow in more quickly than K+ flows out

Answer 32

acetylcholine

Question 33

fast EPSP that is small in magnitude but results in membrane depolarization due to ligand-gated Na+/K+ channels

Answer 33

Type 1 synapse

Question 34

neurotransmitters in Type 1 synapse

Answer 34

glutamate

Question 35

type 1 synapse needs what?

Answer 35

summation

Question 36

slow IPSP that is inhibitory and involves opening of ligand-gated chloride channels

Answer 36

type 2 synapse

Question 37

neurotransmitters in type 2 synapse

Answer 37

GABA, glycine