Brainscape's Knowledge GenomeTM

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


See full index

Neuroscience - general > Synaptic transmission > Flashcards

Synaptic transmission Flashcards

1
Q

what structure is considered the ‘trigger zone’ that must reach threshold potential to achieve action potential?

A

the axon hillock

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

what are the two main inhibitory neurotransmitters

A

GABA and glycine

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

how is GABA synthesised

A

by removal of the carboxyl group from glutamate using glutamate decarboxylase

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

how many neurons and synapses are in the human brain

A

86 billion neurons and 100 trillion synapses

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

what is the main excitatory neurotransmitter in the central nervous system

A

glutamate

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

transcriptional regulation of what gene causes GABA synthesis

A

GAD1

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

what type of synapse is primarily associated with excitatory neurons

A

axo- dendritic synapse

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

how do excitatory and inhibitory synapses look different (molecular distinctions)

A

excitatory synapses - often asymmetric (due to thick specialisation of organiser proteins and cytoskeleton), more obvious accumulation of NT vesicles near the active zone release site
inhibitory synapses - are symmetric (thin specialisation of organiser proteins and cytoskeleton)

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

what ion flux during excitatory transmission

A

sodium and calcium

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

what ion s flux during inhibitory transmission

A

chlorine

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

what tools can be used to investigate DNA molecular neuroscience

A

promoter studies, identifying mouse mutants, disease forming mutations in humans

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

what tools can be used to investigate RNA molecular neuroscience

A 
cDNAs, PCR and in-situ hybridization
Gene profiling (e.g. microarrays, RNAseq).
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what tools can be used to investigate protein molecular neuroscience

A

Antibody staining (western blotting or immunocytochemistry).

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

what molecular component causes variation in neuronal morphology

A

cytoskeleton - actin filaments, intermediate filaments, microtubules

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

where is the actin cytoskeleton often associated

A

in a cortical network enriched in terminal regions

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

where are the microtubules in neurons and how are they orientated

A

Microtubules orientated unidirectionally in the axon compartment but bi-directionally in the dendrite

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

what regulatory proteins are associated with microtubules

A

Tau and MAP2

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

whats the main function on microtubules in neurons

A

makes tracks for transport

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

how do microtubules aid transport of things inside neurons

A

kinesin (+end directed motor protein) binds one end to cargo the other to the microtubule, and walks (from soma) along the microtubule by hydrolysing ATP

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

what is the main orientation of inhibitory synapses

A

axo-somatic synapes

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

what is the common inhibitory NT vesicle transporter protein

A

Inhibitory amino acid vesicle transporter IAAT

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

what is the structure of voltage-gated sodium channels

A

one protein sequence that contains 4 domains each of which has a voltage sensor and 1/4 of the pore. each domain is made up of six alpha-helical transmembrane segments + reentrant loop (between S5 & S6)

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

what is the structure of voltage-gated potassium ion channels

A

made up of one protein sequence making up one domain of 6 alpha helical transmembrane loops. has a voltage sensor in the form of +ve K amino acids in the 4th segment. the reentrant loop between S5 & S6 makes up the pore

24
Q

what senses voltage in voltage gated sodium and potassium ion channels

A

+ve amino acids K and R in the fourth transmembrane segment of each domain

25
Q

what makes up the pore of voltage gated ion channels

A

the reentrant loop between the 5th and 6th transmebrane segments

26
Q

what are the thresholds for activation and inactivation of voltage-gated sodium ion channels

A

for activation about -50 mV

for inactivation about 0 mv

27
Q

what are the thresholds for activation and inactivation of voltage-gated potassium ion channels

A

activation about 0mV

inactivation about +50mV

28
Q

what are the two ways of bridging the synaptic gap

A

electrical synapse and chemical synapse

29
Q

what is the structure of electrical synapses

A

pre and postsynaptic membranes are in close proximity so gap junctions can form (6 subunit hemi dimers on each membrane join) for continual access

30
Q

what two ways can you turn off a chemical synaptic signal

A

reuptake and diffusion away

enzymatic degradation in the case of acetylcholine

31
Q

what does excitatory stimulation cause in the post synaptic cell

A

depolarisation

32
Q

what does inhibitory stimulation cause in the post synaptic cell

A

hyperpolarisation

33
Q

where is the major inhibitory input on the neuron

A

onto the soma

34
Q

what is synaptotagmin and its role in synaptic transmission

A

a protein that binds calcium and changes its conformation to allow storage NT vesicles to see the calcium signal and collaborate with SNARE proteins to drive fusion

35
Q

what are SNARE proteins and what is their role in synaptic transmission

A

Proteins on both NT vesicle and plasma membranes (with complementary domains) that come together to allow fusion and release of neurotransmitters into the synaptic cleft. (trigger by synaptotagmin)

36
Q

what is the brief structure of glutamate receptors on the post synaptic membrane

A

four subunits with glutamate binding sites on the outside allowing cation flux

37
Q

what organising protein is associated with excitatory synapses

A

PSD-95

38
Q

what organising protein is associated with inhibitory post synaptic cells

A

gephrin

39
Q

what is the brief structure of glycine receptors

A

five subunits make the ion channel with glycine binding on the outside allowing anion flux

40
Q

what do organising proteins like PSD-95 and gephrin do to help synaptic segregation

A

selectively recruit tags (neurexins and neuroligins) that allow organising of synapses

41
Q

what molecules are tags for pre synaptic neurons

A

neurexins

42
Q

what molecules tag post synaptic neurons

A

neuroligins

43
Q

which neuroligins tag inhibitory neurons and which tag excitatory ones

A 
glutaminergic = neuroligins 1, 3 and 4
glycinergic = neuroligin 2
44
Q

what is temporal summation

A

successive synaptic inputs before the neuron has time to recover can sum together to produce a greater overall effect

45
Q

what is spatial summation

A

multiple synaptic inputs to different parts of the neuron can sum together produce=ing a greater overall effect

46
Q

how is action potential intensity coded

A

by number of action potentials - AP frequency roughly proportional to the log of stimulus intensity up to a maximum

47
Q

how is action potential modality coded

A

by which axon is activated

48
Q

what is synaptic plasticity

A

activity-dependent changes to synaptic strength

49
Q

which structure is more sensitive to long term potentiation

A

hippocampus

50
Q

which structure shows long term depression but not much long term potentiation

A

cerebellum

51
Q

what is long term depression of neurons

A

an activity-dependent reduction in the efficacy of neuronal synapses lasting hours or longer following a long patterned stimulus (low frequency -> smaller response)

52
Q

what is long term potentiation of neurons

A

a process by which synaptic connections between neurons become stronger with frequent activation (high frequency -> larger response)

53
Q

what is metaplasticity

A

Metaplasticity refers to neural changes that are induced by activity at one point in time and that persist and affect subsequently induced LTP or LTD

54
Q

how is metaplasticity different from synaptic plasticity

A

The ‘meta’ part of the term reflects the higher-order nature of the plasticity — that is, the plasticity of synaptic plasticity.
Essentially, metaplasticity entails a change in the physiological or biochemical state of neurons or synapses that alters their ability to generate synaptic plasticity

55
Q

what is the chemistry of glutamate clearance

A

In astrocytes glutamate is converted into glutamine by glutamine synthetase (GS), released into the extracellular space, taken up by neurons and converted back into glutamate by phosphate activated glutaminase (GA).

56
Q

what are the main target receptors for glutamate

A

Kainate receptors, metabotropic glutamate receptors (mGluRs), and especially NMDA receptors

Neuroscience - general (13 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions