Brainscape's Knowledge GenomeTM

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


See full index

Neurology > Membrane potential, action potentials and synaptic transmission and perception > Flashcards

Membrane potential, action potentials and synaptic transmission and perception Flashcards

1
Q

what is a membrane potential

A

difference in charge between the extracellular fluid and intracellular fluid

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

What is the concentration of sodium inside and outside of the cell

A

out 150mmol

in 15mmol

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

What is the concentration of potassium ions inside and outside of the cell

A

out 5mmol

in 150mmol

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

What is the concentration of anions inside and outside of the cell

A

out 0

in 65mmol

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

what has higher permeability potassium or sodium ions

A

potassium

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

If the positive concentration gradient is directed outside the cell which way is the electrical gradient directed

A

inside the cell

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

what is the main cause for the resting potential.

A

K+ diffuse out of the cells which creates a positive charge outside the cell.

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

What is the formula to work out the membrane potential

A

E = 61 log conc out/ conc in

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

Na+ enter the cell from the outside(extracellular) which makes the potential more positive to overall charge. What is the potential differnence

A

-70mv

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

Quickly describe the process of an ap being generated- using the graph with certain channels opening etc

what is threshold potential to

A

At resting potential , stimulus cause NA to open and reach threshold of -55 positive feedback causes voltage. gated sodium channels to open from threshold to to peak.
Pd now at +30mv , Na volatge gated close which is triggered at threshold but slow.
Efflux of K+ causes repolarisation. Potassium channels( I gate) open at threshold potential put slow. Pd overshoots causing hyperolarisation where potassium channels close.

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

What is the refractory period?

what molecules restore this

A

Ap ions are in the wrong place so restored by PAMPS

this makes sure the cell can recover and AP are only transmitted in one direction

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

What is GABA

A

GABA is an inhibitory neurotransmitter which binds to the GABA a receptor and causes hyperpolarisation of the post synaptic membrane due to causing an influx of K+
GABAb - potassium efflux
GABAa - influx of CL-

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Temporal summation

A

2 or more AP I quick succession release enough neurotransmitter to trigger AP on next neuron

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

Spatical summation

A

pre neurones simultaneously coverage to release small amount of neurotransmitter - multi stimuli in 1 response

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

soma

A

body of the neurone

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

what does the axon do

A

carries impulses from the body

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

axon hillock

A

soma binds to the axon- where the theshold potential is met , all or nothing potential

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

intensity of AP

A

firing frequency

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

difference between neurone and a nerve

A

Neurone is one cell and a nerve is made up from multiple nerves.

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

Excitable cells – can generate an electrical current through ion channels what are the two types of excitable cells

A

muscle and nerve

21
Q

Neurofibrils are special features of neurones - what do they do?

A

provide cellular stability ad structure

  • Chains of tuberin running along axon to cell body and axon terminal
  • Moves vesicles along axon with foot like projections
22
Q

What are neurotubules?

A

microtubule transport system ,
chains of tubulin that run from the soma to the axon terminal
and have transport molecules on the chains that move vesicles along the outside of tubules -foot like process

23
Q

cell body —- axon terminal carries:

A

neurotransmitter vesicles, proteins and lipids on kinesis

24
Q

axon terminal —– cell body carries:

A

cell debris on dynein - energy dependent

25
Q

wha does myelin provide and where does depolarisation take place

A

electrical insulation - and depolarisation takes place at the nodes of ranvier

26
Q

what is saltatory conduction

A

ions only diffuse at gaps. local currents elongated speeding up transmission

27
Q

Describe what a Schwann cell is where it is found

A
  • In peripheral nervous system, Schwann cell wraps around one neurone.
28
Q

describe what an oligodendrocyte is and where it is found

A
  • In central nervous system, oligodendrocyte has multiple arms which wraps around multiple axons.
29
Q

grey matter

A

cell bodies

30
Q

white matter

A

axons

31
Q

grey matter is found where in the brain

A

peripherally but central in the spinal cord

32
Q

what are glial cells

A

non-neuronal cells in the CNS

33
Q

4 types of glial cells

A

oligodendrocytes
astrocytes
microglia
ependymal

34
Q

what are astrocytes

A

maintain microstructure,

blood brain barrier

35
Q

what are microglia and what do they produce

A

immune cell ( monocyte) produce growth factors

36
Q

what are ependymal cells

A

produce CSF , line CSf spaces, cilia aid CSF movement

37
Q

3 connective tissues of nerves

A

endoneurium - connective tissue around myelin sheath of ash myelinated nerve fibre in PNS
perineurium - surrounds bundle( fascicles) of nerve fibres within a nerve
fascicles - bundle of axons , nerve fascicle - PNS in CNS this is known as a nerve tract
epineurium - surrounds peripheral nerve -BV

38
Q

3 main roles of peripheral nerves

A

motor, sensory and autonomic

39
Q

efferent neurones

A

away from the CNS

40
Q

afferent neurones

A

towards the CNS

41
Q

what is fibre class based on

A

diameter and myelination

42
Q

What are Adelta fibres function

A

fast pain and temperature towards the CNS

43
Q

What are Abeta fibres function

A

afferent for touch and pressure

44
Q

somatic sensory modalities (4)

A

tactile - pressure, touch and vibration
pain
proprioception - positions of limbs and static movement
thermal

45
Q

mechanoreceptors

A

deformation and stretching

46
Q

thermoreceptors

A

temp

47
Q

nociceptors

A

pain

48
Q

What are the 2 types of nerve endings

A

free nerve endings - dendrites sit in tissue where single detected
encapsulated nerve endings - deformed and enhances sensitivity - touch pressure and vibration

Neurology (13 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions