brainstem and CNs 9-12

Question 2

Medulla oblongata: external features

what do descending motor fibre tracts do at the pyramids?

Answer 2

decussitate

Question 3

What does the olive contain?

Answer 3

contains inferior olivary nuclei complex

Question 4

what is the nuclus gracilis

Answer 4

where ascending sensory fibres in the fasciculus gracilis tract synapse with the medulla

Question 5

what is the nucleus cuneatus

Answer 5

where ascending sensory fibres in the fasicuculus cunetus tract synapse in the medulla

Question 6

what 4 fibre types does CN IX (glossopharyngeal) have and what do they supply

Answer 6

Motor:
- supplies stylopharyngeus (for chewing)

Parasympathetic supplying:
- parotid salivary gland

Sensory fibres from:
- carotid body and sinus to detect blood pressure changes

special sensory fibres from:
taste buds of posterior 1/3 of tongue

Question 7

Medulla oblongata: CN X

what 3 places does the CNX (vagus) nerve supply

Answer 7

• neck
• thorax
• abdomen

Question 8

Medulla oblongata: CN X (Vagus)

what 4 fibres does the vagus nerve (CN X) have and what do they do

Answer 8

motor fibres:
- supply soft palate, pharynx and larynx muscles

parasympathetic fibres:
- supply glands and smooth muscles of digestive tract

sensory fibres:
- receives information from body viscera down to abdomen

special sensory:
- receives information from palate and upper oesophagus

Question 9

Medulla Oblongata: CN XII

what fibres does the CN XII have and where does it supply

Answer 9

• motor fibres that control almost all muscles of tongue that are involved in shape and position of the tongue in the mouth