Synapses

Question 1

what are the two broad classes of synapses?

Answer 1

electrical and chemical

Question 2

size of an electrical synaptic cleft?

Answer 2

3/5 nM

Question 3

size of a chemical synaptic cleft?

Answer 3

20-40 nM

Question 4

which synapse has synaptic continuity?

Answer 4

electrical

Question 5

which synapse has gap junctions?

Answer 5

Electrical

Question 6

which synapse has presynaptic and postsynaptic elements?

Answer 6

Chemical

Question 7

what is the agent of transmission for an electrical synapse? chemical?

Answer 7

ionic current? neurotransmitters stored in vescicles

Question 8

which synapse has a delay? how long is that delay?

Answer 8

chemical synapses have .3-5 ms delays

Question 9

What is the direction of potential movement in electrical? chemical?

Answer 9

bi-directional, uni-directional

Question 10

in a chemical synapse is the response excitatory or inhibitory? what about for an electrical synapse?

Answer 10

either or

always excitatory

Question 11

what is the function of a connexon?

Answer 11

synaptic element that is aligned so pore can allow current flow (1.5-2 nM in size)

Question 12

what are the benefits of an electrical synaps?

Answer 12

rapid, pure diffusion, but it is a simple behavior

Question 13

which synapse form is the pre-dominant form for communication?

Answer 13

chemical

Question 14

describe an axo-somatic synapse?

Answer 14

in between axon of presynaptic to soma of post-synaptic (IPSP)

Question 15

describe an axo-dendritic synapse?

Answer 15

axon of pre to dendrite of post (EPSP) this is most common

Question 16

describe axo-axonic synapse?

Answer 16

axon to axon, has no effect on ap controls how much neurotrasnmitter is released

Question 17

advantages of chemical synapses?

Answer 17

complex behaviors, requires energy, synaptic delay

Question 18

role of the pre-synaptic terminal?

Answer 18

synthesis, storage, and release of transmitter

Question 19

role of post-synaptic terminal?

Answer 19

receptive process responsible for binding the transmitter to receptor and activation

Question 20

where are neurotransmitters stored?

Answer 20

vescicles that protect them from enzymatic degradation

Question 21

what is one quanta?

Answer 21

contents of 1 vescicle, usually a fixed number

Question 22

what is one quanta of ACh

Answer 22

2000

Question 23

explain the dale principle

Answer 23

a neuron will release the same neurotransmitter at all of its sites

Question 24

explain the co-existence principle

Answer 24

some neurons can release more than one transmitter

Question 25

describe the process of neurotransmitter release?

Answer 25

AP arrival opens calcium channels, calcium causes vesicles to fuse with membrane, transmitter is released by exocytosis into cleft

Question 26

what is a post-tetanic potentiation?

Answer 26

increase in transmitter release after a high frequency train of APs

Question 27

what happens to calcium channels after a high use of the nerve?

Answer 27

cacium channels become leaky

Question 28

what enzyme synthesized ACh? what breaks it down?

Answer 28

choline acetyltransferase | acetylcholinesterase

Question 29

what is GABA synthesized from?

Answer 29

Glutamate

Question 30

are GABA and glycine inhibitory or excitatory?

Answer 30

inhibit

Question 31

is glutamate an inhibitory or excitatory transmitter?

Answer 31

excitatory

Question 32

significance of glutamate?

Answer 32

precursor to GABA

Question 33

what is used to synthesize serotonin?

Answer 33

tryptophan

Question 34

what kind of food is tryptophan found in?

Answer 34

nuts, cheese, red meat

Question 35

what can happen with a tryptophan deficiency?

Answer 35

anxiety and depression

Question 36

what are three types of catecholamines?

Answer 36

norepinephrine, epinephrine, dopamine

Question 37

what is needed for catecholamines?

Answer 37

tyrosine

Question 38

what produces catecholamines?

Answer 38

adrenal medulla

Question 39

T/F low levels of catechalomine circulation is associated with stress

Answer 39

false

Question 40

what are the two main receptor functions?

Answer 40

recognizing transmitters and activation

Question 41

what are directly gated receptors?

Answer 41

one molecule that does both the recognizing and activation (rapid)

Question 42

what are indirectly gated channels?

Answer 42

different molecule for recognition function and activation function (slow but long lasting)

Question 43

Name of the ACh directly gated and indirectly gated transmitter

Answer 43

directly; nicotinic | indirectly: muscularinic

Question 44

what is the function of the nicotinic receptor and where is it located?

Answer 44

it opens both sodium and potassium but potassium over powers EPSP. neuromuscular junction

Question 45

function and location of muscarinic receptor?

Answer 45

open/ close potassium can be IPSP or EPSP in PNS

Question 46

what in the response to Glutamate regardless of type

Answer 46

EPSP. direct opens sodium indirect idk

Question 47

does dopamine have indirect or direct terminals?

Answer 47

indirect either opens potassium or closes calcium (calcium opens vescicles)

Question 48

Name of direct GABA terminals? indirect?

Answer 48

GABA A | GABA B

Question 49

Effect of GABA A

Answer 49

opens chloride channels (IPSP)

Question 50

Effect of GABA B

Answer 50

closes calcium (inhibition)

Question 51

what does an agonist do?

Answer 51

binds to recognition portion and produces an effect

Question 52

what does an antagonist do?

Answer 52

binds to recognition portion but fails to produce effect. it keeps other receptors from binding

Question 53

how does acetylcholine become inactivated?

Answer 53

acetylcholine esterase breaks it into choline and acetate, sent back to presynaptic cleft

Question 54

How do most transmitters get inactivated?

Answer 54

with energy they are reabsorbed by the presynaptic element