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Flashcards in W8 - Neural System Deck (95)
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1
Q

What comes under the CNS

A

Brain

Spinal cord

2
Q

What comes under the PNS

A

Cranial nerves (12 pairs)

Spinal nerves (31 pairs)

3
Q

Parts of the brain

A

Cerebrum

Cerebellum

Diencephalon

Brain stem

4
Q

What are the 4 lobes of the cerebrum?

A

Frontal

Parietal

Temporal

Occipital

5
Q

What is the cerebellum responsible for?

A

Coordinating voluntary movements, including motor skills like:

Balance
Coordination
Posture

6
Q

What is the Diencephalon responsible for?

A

Processes sensory info + has autonomic control

7
Q

What does the Diencephalon contain?

A

Epithalamus

Thalamus

Hypothalamus

Ventral thalamus

8
Q

What is the brainstem responsible for?

A

Involuntary actions of the body

i.e heat beat + breathing

9
Q

What does the brain stem connect what to what?

A

Brain to spinal cord

10
Q

What are the 2 main parts of the brain?

A

Left = Motor area

Right = Sensory area

11
Q

What does TMS stand for?

A

Transcranial magnetic stimulation

12
Q

CRANIAL NERVES

Which is a sensory nerve involved with the nose for smell?

A

Cranial nerve 1

13
Q

CRANIAL NERVES

Which is a sensory nerve involved with the eye for vision?

A

Cranial nerve 2

14
Q

CRANIAL NERVES

Which is a motor nerve involved with the upper eyelid + eyeball?

A

Cranial nerve 3

15
Q

CRANIAL NERVES

Which is a motor nerve involved with the movement of the eyeball?

A

CN 4

16
Q

CRANIAL NERVES

Which is a sensory/motor nerve involved with touching, pain + chewing ?

A

CN 5

17
Q

In what 2 ways are nerves grouped?

A

Afferent

Efferent

18
Q

What do afferent nerves do?

A

Carry signals FROM receptors in the periphery TO the CNS.

19
Q

What type of neurones are afferent neurones?

A

Sensory

20
Q

What do efferent nerves do?

A

Carry impulses away from the CNS to effectors i.e muscles.

21
Q

What type of neurones are efferent neurones?

A

Motor

22
Q

Examples of sensory neurones

A

Baroreceptors

Chemoreceptors

Mechano/proprioreceptors

Metaboreceptors

Thermoreceptors

Nociceptors

23
Q

What are baroreceptors sensitive to changes in?

A

bp

24
Q

What do nociceptors detect?

A

Pain

25
Q

What is an association neurone also known as?

A

An interneurone

26
Q

What do interneurones do?

A

Connect spinal motor + sensory neurones by passing the afferent transmission to the efferent response w/out need to involve the brain.

However they can also communicate with each other to form circuits of various complexity.

27
Q

What is a myotatic stretch reflex?

A

Contraction of a muscle in response to its passive stretching.

28
Q

What does the stretch reflex do when a muscle is stretched?

A

Regulates the length of the muscle by ⬆️ its contractility as long as the stretch is w/in the physiological limits.

29
Q

What does the brainstem consist of?

A

Medulla

Pons

Midbrain regions

30
Q

Which division comes off the CNS?

Afferent or Efferent?

A

Afferent

31
Q

Which division comes off the PNS?

Afferent or Efferent?

A

Efferent

32
Q

What are the 3 main components of the stretch reflex?

A

Muscle spindle responding to stretch

Afferent nerve fibre carrying sensory impulse from spindle –> spinal cord

Efferent spinal cord motor neurone activating the stretched muscle fibres

33
Q

Efferent division in the autonomic nervous system

A

Includes involuntary processes by involving the SNS + PNS

34
Q

Efferent division in the somatic nervous system

A

Includes motor neurones to initiate skeletal muscle function

35
Q

What senses change in the internal + external env through sensory receptors

A

Afferent neurons

36
Q

What analyses the sensory info, stores some aspects + makes decisions

A

Interneurons

37
Q

What neurone responds to stimuli by initiation of action?

A

Efferent

38
Q

What is nervous tissue composed of?

A

Neurones

Neuroglia (supporting cells)

39
Q

Where can the 6 types of neuroglia be found?

A

4 in the CNS

2 in the PNS

40
Q

What are the 4 neuroglia/glial cells in the CNS?

A

Astrocytes

Microglial cells

Epndymal cells

Oligodendrocytes

41
Q

What are the 2 neuroglia in the PNS?

A

Satellite cells

Schwann Cells

42
Q

What are dendrites?

A

Motor neurones

43
Q

How long are dendrites?

A

Short

BUT have a large surface area for receiving signals from other neurones.

44
Q

What do dendrites do?

A

Convey incoming messages towards the cell body

45
Q

What is the dendrite region also known as?

A

Receptive input region

46
Q

What do astrocytes do?

A

Regulate electrical transmission in the brain

47
Q

Do neuroglia generate or conduct nerve impulses?

A

No

48
Q

What are the 2 components of a motor unit?

A

Alpha-motor neuron (AMN)

Muscle fibres innervated by the AMN

49
Q

What are the 3 types of motor unit?

A

Slow / type 1

Fatigue resistant / type IIa

Fast fatiguing / type IIx

50
Q

What does the axon hillock do?

A

Acts like a manager:

Summing the total inhibitory + excitatory signals.

  • If the sum of these signals exceeds a certain threshold, the AP will be triggered + an electrical signal will be transmitted down the axon AWAY from the cell body.
51
Q

What on the neuron services as a contact point?

A

Synapse

52
Q

What do Schwann Cells play an essential role in?

A

Development, maintenance, function + regeneration of peripheral nerves.

53
Q

In the mature nervous system, what are the 2 classes that Schwann Cells can be categorised into?

A

Myelinating cells

Nonmyelinating cells

54
Q

What is the node of Ranvier?

A

1-2 micrometer gap between the glial cells of the myelin sheath.

55
Q

When is the node of Ranvier ONLY ever present?

A

When the axon of a neuron is myelinated.

56
Q

What is the importance of the myelin sheath?

A

For the speed of the impulses

57
Q

What are the 3 nerve fibre groups?

A

A - Alpha, beta, gamma

B - Nerve fibres

C - Nerve fibres

58
Q

Are A - Alpha, beta, gamma fibres myelinated?

A

YES

59
Q

Are B - Nerve fibres myelinated?

A

Moderately

60
Q

Are C - Nerve fibres myelinated?

A

NO

61
Q

What happens to the velocity of the AP when there’s more myelination?

A

Faster

62
Q

What happens to the velocity of the AP when there’s a bigger axon diameter?

A

Faster

63
Q

What happens to the velocity of the AP when temp increases?

A

Faster

64
Q

What are the structural classifications of neurones?

A

Multipolar

Bipolar

Unipolar

65
Q

Where is the cell body in a multipolar neurone?

A

In the dendrites

66
Q

Where is the cell body in a bipolar neurone?

A

Middle

67
Q

Out of the 3 classifications of neurones, which has the shortest axon?

A

Bipolar neurone

68
Q

Where is the cell body in a unipolar neuron?

A

Middle but to the side

69
Q

What do APs do?

A

Reverse the membrane potential + then restore it to a resting state

70
Q

What are the excitable cells?

A

Neurons

Muscle

Endocrine

71
Q

Define a membrane potential

A

Difference in the amount of electrical charge inside + outside of cell

72
Q

Define a physics potential

A

Separation of charge

73
Q

What charge does a neurone have at rest?

A
  • ive

- 70mV

74
Q

What are the main ions inside + outside neurones?

A

Na+

K+

Cl-

Organic anions

75
Q

What causes there resting membrane potential?

A

No. of +ively K+ inside + outside the cell

76
Q

What channels are CLOSED at the resting potential?

A

All voltage-gated Na+

Most voltage-gated K+

77
Q

What does the Na+/K+ transporter do at resting potential of the membrane?

A

Pumps K+ INTO cell

Na+ OUT

78
Q

What happens to the resting membrane potential in response to depolarisation?

A

Some Na+ channels open = Na+ INTO cell

Membrane starts to depolarise so charge across membrane decreases.

IF threshold of excitation is reached = ALL Na+ channels open

79
Q

What happens at the peak AP?

A

Na+ channels close

K+ channels open

= K+ leave cell = membrane eventually becomes hyperpolarized.

80
Q

What causes a neurone at rest to be slightly negative compared to the surrounding fluid?

A

The movement of K+ ions OUT of cell

81
Q

What is it called when the membrane is hyperpolarized and can’t fire impulses?

A

In the refractory period

82
Q

What must happen within a neuron for it to reach its threshold in order to carry out an action potential?

A

Na+ enter cell via open channels to make inside of cell increasingly less -ive

83
Q

What are the types of membrane ion channels?

A

Leakage channels

Voltage gated channels

Ligand-gated ion channels

84
Q

What are the types of synapse?

A

Chemical

Electrical

85
Q

How do synaptic vesicles release neurotransmitters?

A

By exocytosis

86
Q

Name an excitatory NT

A

Glutamate

87
Q

Name an inhibitory NT

A

Gamma aminobutyric acid

88
Q

Name the NT that function as excitatory + inhibitory NTs

A

Acetylcholine

Noradrenaline

89
Q

What is the excitatory postsynaptic potential (EPSP) responsible for?

A

Depolarisation via the ligand-gated Na+ channels

90
Q

What is the inhibitory postsynaptic potential (IPSP) responsible for?

A

“More” -ive or hyper polarised via ligand-gated Cl- or K+ channels

91
Q

What are the types of signal summation?

A

Spatial summation

Temporal summation

92
Q

What is Spatial summation?

A

When more primary afferent (presynaptic) neurones are activated simultaneously until enough NT is released to activate an AP in the spinal cord (postsynaptic) neuron.

93
Q

What is temporal summation?

A

Happens when 1 presynaptic neurone releases NT many times over a period of time

94
Q

Which part of the brain coordinates movement?

A

Cerebellum

95
Q

Which are the functional divisions of the PNS?

A

Somatic nervous system

Autonomic nervous system