Week 2 Neuro

Question 1

where are the cell bodies of nociceptors located

Answer 1

dorsal root ganglion

trigeminal ganglia

Question 2

what is allodynia

Answer 2

innocuous stimuli now elicits pain

Question 3

what fibres are first pain mediators

Answer 3

A delta

Question 4

What fibres mediate second pain response

Answer 4

c fibres

Question 5

what is the primary transmitter in pain transmission between nociceptors and second order neurones

Answer 5

glutamate

Question 6

what things suppress glutamate transmission

Answer 6

interneurons releasing GABA or glycine suppress transmission as do opiates and cannabinoids

Question 7

What tracts in the spinal cord are the nociceptive tracts

Answer 7

spinothalamic

spinoreticular

Question 8

what is the spinothalamic tracts role in pain transmission

Answer 8

A delta pain from lamina I terminated in posterior nucleus of the thalamus
Neurones from lamina v terminate in the posterior and ventroposterior nucleus of the thalamus.
Pain perception requires simultaneous firing in both pathways

Mediated first pain and temp

Question 9

What is the spinoreticular tracts role in pain

Answer 9

largely transmits c fibre pain

connects with periaqueductal grey matter and parabrachial nucleus

involved in autonomic response to pain, arousal and fear of pain

Question 10

what is the difference between pain and nociceptin

Answer 10

nociception may occur in absence of pain

pain is awarenedd of suffering

Question 11

what fibres prevent pain when nociceptors are activated

Answer 11

A beta

Question 12

what is gate control theory

Answer 12

the theory that not all nociceptive signals reach the brain as ‘pain’

Question 13

where does the gate control theory occur

Answer 13

substantia gelatinosa

Question 14

what are thermoreceptors

Answer 14

neurones that are specialised to respond to small changes in skin temperature

Question 15

define dendrite

Answer 15

receive inputs from other neurones and convey graded electrical signals passively to soma

Question 16

what is the axon hillock

Answer 16

site of initiation of the all or none action potential

Question 17

define axons

Answer 17

conducts output signals as action potentials to other neurones

Question 18

define synapse

Answer 18

point of chemical communication betweene neurones

Question 19

where are unipolar neurones

Answer 19

peripheral autonomic neurones

Question 20

where are pseudounipolar

Answer 20

dorsal root ganglion

Question 21

where are bipolar neurons

Answer 21

retinal bipolar neurone

Question 22

where are multipolar neurones

Answer 22

lower motor neurone

Question 23

what is membrane resting potential

Answer 23

-70

Question 24

what is threshold potential for AP

Answer 24

-60

Question 25

what is overshoot

Answer 25

when the cell becomes positively polarised briefly during the AP

Question 26

What is undershoot

Answer 26

when the cell becomes more negative after the AP

Question 27

What ion channel mediates the upstroke and what mediated the down stroke

Answer 27

upstroke - sodium | down stroke potassium

Question 28

what is the predominante intracellular cation

Answer 28

potassium

Question 29

what is the predominant extracellular cation

Answer 29

sodium

Question 30

name the demyelinating disorder of the PNS

Answer 30

guillian barre

Question 31

what is the most common types of synapses

Answer 31

axodendritic | axosomatic

Question 32

what is the exhitory transmitter in the CNS

Answer 32

glutamate - causes depolarisation

Question 33

what is the inhibitory transmitter in the CNS

Answer 33

GABA or glycine - hyperpolarises the cells and prevents action potentiasl

Question 34

cation

Answer 34

positive

Question 35

anion

Answer 35

negative

Question 36

What is spatial summation

Answer 36

many inputs converge upon a neurone to determine its output

Question 37

What is temporal summation

Answer 37

a single input modulates the output by variation in action potential frequency of that input.

Question 38

where are amino acids and amines released from

Answer 38

synaptic vesicle

Question 39

where are peptide released from

Answer 39

secretory vesicles

Question 40

what ion channels mediate fast neurotransmission

Answer 40

ionotropic ligance gated ion channels

Question 41

what channels mediate slow neurotrnamission

Answer 41

g protein coupled receptors

Question 42

what ion induces the release of neurotransmitters in the pre synaptic cleft

Answer 42

calcium

Question 43

what neurotransmitters occur in all cells

Answer 43

glutamate and glycine

Question 44

How are neurotransmitters made

Answer 44

within the neurone themselves made in rER and packaged in Golgi apparatus - then transported to presynaptic terminal by axoplasmic transport where they are stored in vesicles.

Question 45

what is the extracellular anion

Answer 45

chloride

Question 46

what ions are excitatory and which are inhibitory

Answer 46

excitatory = sodium and calcium inhibitory ie cause hyperpolarization = chloride and potassium

Question 47

what drug antagonises sodium channels

Answer 47

lidocaine | favours inhibition

Question 48

what is the name of receptors that are an integral component of the channel they control

Answer 48

ionotropic receptors involved in direct gating

Question 49

what is the name of receptors whose channels they control are distinct from the recetpors

Answer 49

metabotropic receptors (G protein coupled receptors) involved in indirect gating

Question 50

name monoamine neurotranmistters

Answer 50

5-HT histamine acetylcholine

Question 51

Name catecholamines

Answer 51

noradrenaline dopamine adrenaline

Question 52

name amino acids

Answer 52

glutamate GABA glycine

Question 53

what shape of channels are glutamate receptors

Answer 53

tetramers

Question 54

what shape of channels are gaba, glycine and ACh receptors

Answer 54

pentamers

Question 55

what receptor doe benzodiazepines work on

Answer 55

GABAa - enhance chloride entry

Question 56

what receptor does baclofen work on

Answer 56

agonist of GABAb - enhances K current - inhibition

Question 57

what is an interneurone

Answer 57

a locally acting neurone, typically releases GABA and so brings about and IPSP and inhibition, function is local progressing of information

Question 58

what is a projection neuron

Answer 58

a neuron responsible for conveying signal to other parts of the brain, typically releases glutamate so brings about epsp

Question 59

what is a quanta

Answer 59

refers to the release of neurotransmitter from a single vesicle

Question 60

how does a neuron discharge in the absensce of an inhibitory input

Answer 60

rhythmically - inhibitory inputs suppress some action portentials resulting in a irregular pattern of discharge