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Flashcards in Anatomy of the PNS Deck (70)
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1
Q

What are neurones?

A

The basic unit of the nervous system

2
Q

Nucleus?

A

Collection of nerve cell bodies in the CNS

3
Q

Ganglion?

A

Collection of nerve cell bodies in the PNS

4
Q

What part of a neurone connects with other neurones?

A

Dendrites

5
Q

Schwann cells produce myelin in the …?

A

PNS

6
Q

Oligodendrocytes produce myelin in the …?

A

CNS

7
Q

What are the 2 main types of neurones?

A

Multipolar

Unipolar

8
Q

Which type of neurone is more common?

A

Multipolar

9
Q

Nerves vs Neurones

A

Nerves in CNS

Neurones in PNS

10
Q

Multipolar neurones have how many dendrites?

A

2 or more

11
Q

All of what are multipolar neurones?

A

the MOTOR neurones of SKELETAL MUSCLE + ANS

12
Q

Where are the cell bodies of multipolar neurones?

A

CNS

13
Q

Unipolar neurones have….

A

Double processes

14
Q

What are unipolar neurones also known as?

A

Pseudounipolar

Sensory

15
Q

The cell bodies of unipolar neurones are in the CNS

A

FALSE

PNS

16
Q

Multipolar

A

MOTOR

17
Q

Unipolar

A

SENSORY

18
Q

Efferent neurones direction?

A

Towards the body wall, cavity or organ

Away from the brain

19
Q

Efferent?

Affrent?

A

Motor

Sensory

20
Q

Afferent neurone direction?

A

Towards the brain

21
Q

What is a ‘tract’ in the CNS?

A

Collections of axons surrounded by connective tissue and blood vessels

22
Q

Nerves can be either …… or ….. modality?

A

Single or mixed

23
Q

Single modality nerves are either?

A
Somatic motor
Somatic sensory
Special sensory
Sympathetic 
Parasympathetic
Visceral afferent
24
Q

Tracts are usually a …… modality?

A

Single

25
Q

What is mixed modality?

A

Somatic motor, somatic sensory and sympathetic all together in one nerve

26
Q

What does CNV supply i) sensory ii) motor supply to?

A

i) face

ii) muscles of mastication

27
Q

Where does CNV arise?

A

Pons

28
Q

CN VII supplies i) motor ii) special sensory to what?

A

i) muscles of facial expression

ii) special sensory to anterior 2/3rds of tongue

29
Q

What muscles does CN XI innervate?

A

Sternocleidomastoid and trapezius

30
Q

Cranial nerves are named from ANTERIOR TO POSTERIOR, then from MEDIAL TO LATERAL, what is the exception?

A

CNXII is the exception – it jumps back to the medial part of the medulla oblongata

31
Q

How many pairs of spinal nerves are there?

A

31

32
Q

How many pairs of each?

A
8 cervical
12 thoracic
5 lumbar
5 sacral
1 coccygeal
33
Q

Where are spinal nerves found?

A

ONLY in the intervertebral foramina

34
Q

What do spinal nerves connect with?

A

Structures of the body wall via rami

Spinal cord segment of the same number via roots

35
Q

Posterior rami of the spinal cord are smaller than anterior rami

A

TRUE

36
Q

Where do anterior rami provide innervation to?

A

Anterior body wall

Lateral body wall

37
Q

Where do posterior rami provide innervation to?

A

Posterior body wall

38
Q

What is the location of cell bodies of primary afferent neurones?

A

Dorsal root ganglion

39
Q

Dorsal

A

Posterior

40
Q

Ventral

A

Anterior

41
Q

SPINAL NERVES ARE ALL…..

A

MIXED

42
Q

Describe where all sensory axons pass from and to.

A

ALL sensory axons pass from the spinal nerve into the posterior root, then into the posterior rootlets, then into the posterior horn of the spinal cord

43
Q

Describe where all motor axons pass from and to.

A

ALL motor axons pass from the anterior horn of the spinal cord into the anterior rootlets then into the anterior root then into the spinal nerve

44
Q

T4

A

Male nipple

45
Q

T10

A

Umbilicus

46
Q

What does each spinal nerve supply a body segment with?

A

General sensory
Somatic motor
Sympathetics to skin, and smooth muscle of arterioles

47
Q

An area of skin supplied with sensory innervation from single spinal nerve is a?

A

Dermatome

48
Q

What is a myotome?

A

The skeletal muscles supplied by motor innervation by a single spinal nerve

49
Q

What does the innervation of skin by adjacent spinal nerves show?

A

OVERLAP

50
Q

What spinal nerves supply the dermatomes of the lower limb, gluteal region and perineum?

A

L2-CO1

51
Q

What dermatomes are in the upper limb?

A

C5-T1

52
Q

What dermatomes are at the posterior scalp, neck and shoulder?

A

C2-C4

53
Q

What are nerve plexuses?

A

Intermingled ANTERIOR RAMI from a number of adjacent spinal nerves

54
Q

Cervical plexus

A

C1-C4

55
Q

Brachial plexus

A

C5-T1

56
Q

Lumbar plexus

A

L1-L4

57
Q

Sacral plexus

A

L5-S4

58
Q

Where do sympathetics exit the spinal cord?

A

T1-L2

thoracolumbar outflow

59
Q

What do only T1 to L2 segments of the spinal cord have? Why?

A

Lateral horns

For cell bodies of the next sympathetic neurones in the chain

60
Q

Where does sympathetic outflow originate from? Then what is their rout?

A

Brain
Spinal cord
Exit via T1-L2

61
Q

Where does sympathetic outflow originate from? Then what is their route?

A

Brain
Spinal cord
Exit via T1-L2

62
Q

Sympathetic outflow is present in all what?

A

Spinal nerves

63
Q

Where do ‘presynaptic’ sympathetic axons pass?

A

These supply ‘motor’ innervation, so pass through anterior rootlets/root

64
Q

What do presynaptic parasympathetic axons leave the CNS via?

A

Cranial nerves III, VII, IX, X

Sacral spinal nerves

65
Q

Where does the ciliary ganglion travel to?

A

Eye

66
Q

Where does the vagus nerve travel to?

A

Organs of the neck, chest and abdomen, as far as the midgut

67
Q

Where do sacral spinal nerves travel?

A

Hindgut, pelvis and perineum

68
Q

Outline the symptoms of Horner’s.

A

Miosis
Ptosis
Anhydrosis
Increased warmth and redness

69
Q

What causes the symptoms of Horner’s?

A

Impaired sympathetic innervation to the head and neck

70
Q

Suggest causes of compression of the cervical parts of the sympathetic trunk.

A
  • Root of neck trauma.
  • Carotid dissection.
  • Internal jugular vein engorgement.
  • Deep cervical node mets.
  • Pancoast tumour (lung apex).