Brainscape's Knowledge GenomeTM

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


See full index

AQA A level Biology > 6.2 Nerve impulses and synapes > Flashcards

6.2 Nerve impulses and synapes Flashcards

1
Q

What are the 2 types of cells in the nervous system

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

What is the role of the neurones

A

To transmit impulses

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

What is the role of neuroglia

A

Provide either structural and/ or metabolic support to neurones

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

What is the name of the neuroglia used in the AQA spec

A

Schwann cells

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

Draw and label a motor neurone

A

Look at 6.2 slide 4 ppt

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

How do you identify a motor neurone

A

The cell body is at 1 end of the neurone

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

What is an axon

A

A single extension that transmits impulse away from cell body

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

When are dendrites

A

Multiple extension that transmit impulse towards cell body

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

Where does the motor neurone transmit impulse from and to

A

From the central nervous system
To the effectors

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

Where do the sensory neurones transmit impulses from and to

A

From receptors
To central nervous system

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

Where do the intermediate neurones transmit impulses from and to

A

From sensory neurone
To motor neurone

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

In a sensory neurone, what in the name of the single extension that comes from the dendrites and goes towards the cell body

A

Dendron

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

What produces a nervous impulse

A

A potential difference across a membrane

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

What is a potential difference measured in

A

mV

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

When speaking about a potential difference, what charge is relative to what

A

Charge on inside of membrane relative to the charge on the outside of the membrane

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

What measures the potential difference

A

Cathode ray oscilloscope (C.R.O)

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

How does a cathode ray oscilloscope work

A

Uses microelectrodes which produces a graphical trace if change in potential difference over time

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

What causes a potential difference

A

Distribution of ions

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

What ions are used to create a potential difference

A

Sodium ions
Potassium ions

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

If there are fewer ions on the inside of the membrane, describe the charge

A

Inside of membrane is negative relative to the outside of the membrane

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

When the inside of the membrane is negative relative to the outside, what is the membrane said to be

A

Polarised

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

The membrane is at _________ when the inside is negative relative to the outside

A

Resting potential

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

What is the potential difference of a membrane at resting potential, AQA value

A
  • 70 mV
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

There are more ions inside the membrane than the outside, describe the charge

A

Inside of the membrane is positive relative to the outside

25
Q

When the inside of the membrane is positive relative to the outside, what is the membrane said to be

A

Depolarised

26
Q

The membrane is at ________ when the inside of the membrane is positive relative to the outside

A

Action potential

27
Q

What is the potential difference of a membrane at action potential, AQA value

A

+ 40 mV

28
Q

When the SAN sends out a wave of depolarisation, what happens to the ions

A

The ions move into the membrane to make the inside of the membrane positive relative to the outside of the membrane

29
Q

Are the majority of neurones myelinated

A

Yes

30
Q

What does myelin provide

A

Electrical insulation

31
Q

When myelin is around a neurone, what cannot happen

A

Ions cannot move in or out of the membrane so the axon cannot depolarise

32
Q

When there is myelin around a neurone, what is the name of the section where depolarisation can occur

A

Node of Ranvier

33
Q

On a graphical trace of the changes in p.d. across the axon membrane, when the graph increases from resting potential, what is the name of the process

A

Depolarising

34
Q

What happens to the ions when the membrane is depolarising

A

The ions are moving into the membrane

35
Q

When the membrane is repolarising, what happens to the ions

A

The ions are moving out of the membrane

36
Q

In the node of Ranvier, how many sodium ions are transported, and are they transported in or out of the membrane per 1 ATP

A

3 Sodium ions are transport out of the membrane

37
Q

In the node of Ranvier, how many potassium ions are transported, and are they transported in or out of the membrane per 1 ATP

A

2 Potassium ions are transported into the membrane

38
Q

What cells are in the myelin sheath

A

Schwann cells

39
Q

What is resting potential

A

When no nerve impulse has been generated

40
Q

Define action potential

A

A sudden, fast, transitory, and propagated change of resting membrane potential

41
Q

When membrane is at resting potential, what one word is used to describe the membrane

A

Polarised

42
Q

What are the 2 proteins in the membrane that are responsible to keep membrane at resting potential

A
  • Sodium ions and potassium ion pump
  • Leakage channels
43
Q

Is the axon membrane more permeable to potassium ions or sodium ions

A

Potassium ions

44
Q

When the membrane is at resting potential, what leakage channel is open, name the ion

A

Potassium ion leakage channel

45
Q

How does the sodium ion, potassium ion pump help keep the axon membrane at resting potential

A

For every 2 potassium ions pumped in, 3 sodium ions are pumped out, so overall more ions leave the membrane making the inside of the membrane negative relative to the outside, so at resting potential

46
Q

How do the leakage channels help the axon membrane remain at resting potential

A

The axon membrane is more permeable to potassium ions, so potassium ions diffuse out of the membrane which makes the inside of the membrane negative relative to the outside, so at resting potential

47
Q

During action potential, what voltage gated channel protein opens

A

The sodium ion voltage gated channel protein

48
Q

At roughly what voltage do the voltage gated sodium ions channels open

A

Roughly 55 mV

49
Q

When the sodium gated channels open during action potential, what happens

A

Sodium ions rapidly diffuse/ influx into the axon which makes the inside of the membrane positive relative to the outside which momentarily depolarising the membrane

50
Q

What voltage gated channel protein is closed when the membrane is at action potential

A

The potassium ion

51
Q

When the axon membrane repolarises, what happens to the potential difference

A

Falls

52
Q

When the axon membrane repolarises, what happens to the voltage gated channel proteins, state what happens to both

A
  • Sodium ion gates close
  • Potassium ion gates open
53
Q

At roughly what voltage do the sodium gated channel proteins close

A

+40 mV

54
Q

At roughly what voltage do the potassium ion gated channel proteins open

A

+ 40 mV

55
Q

What 2 proteins in the axon membrane are used to repolarise the membrane

A
  • Sodium ion, potassium ion pump
  • Potassium gated channel protein
56
Q

How does the potassium ion gated channel protein cause the membrane to repolarise

A

Potassium ions rapidly diffuse out of the membrane/ outflux which makes the inside of the membrane negative relative to the inside, which leads to the membrane being repolarised

57
Q

What is the main channel protein that restores resting potential

A

The sodium ion, potassium ion pump

58
Q

When looking at a graphical trace from a C.R.O, what is the name of the process that causes the potential difference to drip lower than the resting potential after the membrane has been repolarised

A

Hyperpolarisation

AQA A level Biology (37 decks)

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