Cranial Nerves

Question 1

What do nerves consist of? (2)

Answer 1

• Motor neurons
  -Sensory neurons

Question 2

How many cranial nerves are there?

Answer 2

12

Question 3

Which nerves cater for the eye (3)

Answer 3

• Optic nerve, oculomtor nerve and trochlear nerve
  -opthalamic nerve of trigeminal

Question 4

Name the three divisions of the trigeminal nerve

Answer 4

• Opthalamic division
• Maxillary division
• Mandibular division

Question 5

What is a corneal reflex?

Answer 5

Blinking

Question 6

What does the chiasm do?

Answer 6

Crossing over of the optic nerves

Question 7

Damage to which nerve causes blindess

Answer 7

Optic nerve

Question 8

Name the mixed nerves

Answer 8

• Glossopharyngeal nerve
• Vagus nerve
• Facial nerve

Question 9

Which nerve damage causes weakness to facial muscles

Answer 9

Facial nerve damage

Question 10

Which number is the facial
Nerve

Answer 10

CN VII

Question 11

Damage to which nerve causes tongue muscle weakness

Answer 11

Hypoglossal nerve (CN XII)

Question 12

Which muscle does the trochlear nerve innervate

Answer 12

Superior oblique muscle

Question 13

What is the function of the vestibulocochlear nerve

Answer 13

• Hearing
• Balance

Question 14

On which area of the tongue does the glossopharyngeal nerve have a function

Answer 14

• posterior 1/3 of the tongue (for taste)

Question 15

Damage to which nerve causes deafness

Answer 15

• Vestibulocochlear nerve

Question 16

Explain the process from when light enters the eye (5marks)

Answer 16

1. Light (visual input) enters the eye and travels to the retina
2. The input then enters the optic nerve and travels to the chiasm.
3. At the chiasm, crossing over of the nerves (nerves on the medial side of the eye).
4. The optic nerve leaves the chiasm as optic tracts
5. The optic tracts then enter the visual cortex for the input to be interpreted

Question 17

Which is the main nerve responsible for vision?

Answer 17

Optic nerve (CN II)

Question 18

Name the cranial nerves
- CN VIII
- CN IX
- CN X

Answer 18

• Vestibulocochlear nerve (CN VIII)
• Glossopharyngeal nerve (CN IX)
• Vagus nerve (CN X)

Question 19

What happens if you damage your Oculomotor nerve?

Answer 19

Eye movement is impaired (cannot look up, down or inward)

Question 20

What happens when you damage your vagus nerve?

Answer 20

• Abnormal heart rate
• Palatal, laryngeal and pharyngeal paralysis
• Movement impairment of the oesophagus

Question 21

What happens when your Vestibulocochlear nerve becomes damaged?

Answer 21

Dizziness

Question 22

Which cranial nerve supplies the extrinsic muscles of the eye

Answer 22

Oculomotor nerve

Question 23

Which artery is divided into three sections due to overlapping with a muscle? Also mention the name of this muscle

Answer 23

• Subclavian artery
• Muscle: Anterior scalene muscle