Describe The Functions Of The Cranial Nerves II, III, IX And X

Question 1

What type of nerve is II?

Answer 1

II cranial nerve is the optic nerve.

Question 2

Is II Optic cranial nerve sensory or motor?

Answer 2

The Optic nerve is a sensory nerve only.

Question 3

Is the II Optic cranial nerve sympathetic or parasympathetic?

Answer 3

The Optic cranial nerve has no parasympathetic fibres so is sympathetic.

Question 4

What is the II Optic Cranial Nerve linked to?

Answer 4

It is associated with the sense of vision, it is actually a brain tract because it develops as an outgrowth.

Question 5

What is the III Cranial nerve?

Answer 5

The III cranial nerve is the oculomotor.

Question 6

Is the III oculomotor Cranial nerve motor or sensory?

Answer 6

It is mainly motor, however it has a small sensory function.

Question 7

What type of fibres does the III oculomotor cranial nerve contain.

Answer 7

It contains parasympathetic fibres.

Question 8

What is the purpose of the III Oculomotor cranial nerve?

Answer 8

The oculomotor nerve is responsible for raising eyelids, moving eyes, adjusting amount of light entering, focusing of lenses.

Question 9

What is the purpose of extrinsic muscles?

Answer 9

Extrinsic muscles move the eyeball in its orbits.

Question 10

How many of the six extrinsic muscles are controlled by the III oculomotor cranial nerve?

Answer 10

Four of the six extrinsic muscles are controlled by the oculomotor.

Question 11

In the III Oculomotor cranial nerve parasympathetic motor fibre reaches where?

Answer 11

The parasympathetic motor fibre reaches the sphincter papillae to make the pupil constrict.

Question 12

In the III oculomotor cranial nerve what muscle controls the lens shape?

Answer 12

The muscle controlled, is the ciliary muscle.

Question 13

In the III oculomotor cranial nerve what do the sensory fibres do?

Answer 13

The sensory fibres within the III oculomotor cranial nerve is associated with muscle condition.

Question 14

Which cranial nerve is IX?

Answer 14

IX cranial nerve is the glossopharyngeal.

Question 15

The cranial nerve IX Glossopharyngeal has what fibres linked to it?

Answer 15

IX glossopharyngeal cranial nerve has both parasympathetic and sympathetic fibres attached to it.

Question 16

In the glossopharyngeal IX cranial nerve what do the parasympathetic fibres do?

Answer 16

The parasympathetic fibres are motor fibres and transmit impulses to the pharynx muscles used in swallowing and to the salivary glands. They also provides nerves to parts of the tongue.

Question 17

In the IX glossopharyngeal cranial nerve, what does the sensory fibre do?

Answer 17

The sensory fibres transmit impulses from the pharynx, tonsils, posterior tongue and carotid arteries.

Question 18

Which nerve is the X cranial nerve?

Answer 18

The X cranial nerve is the vagus nerve.

Question 19

In the X Vagus cranial nerve which type of fibres does it have?

Answer 19

The X vagus, cranial nerve has both sympathetic and parasympathetic fibres.

Question 20

What is the special fact about the X Vagus, cranial nerve?

Answer 20

It is the only nerve that extends beyond the head and neck reaching the thorax and abdomen.

Question 21

Within the X Vagus Cranial Nerve what does the somatic motor fibres do?

Answer 21

The somatic motor fibres transmits impulses to muscle used for speech and swallowing.

Question 22

What type of fibres does the X Vagus cranial nerve have?

Answer 22

It has both parasympathetic and sympathetic fibres.

Question 23

Within the X Vagus cranial nerve what is the autonomic motor fibres function?

Answer 23

They transmit impulses to the heart, smooth muscles, thoracic and abdominal glands.

Question 24

Within the X Vagus cranial nerve, what is the sensory fibres function?

Answer 24

The sensory fibres transmit impulses from the pharynx, larynx, oesophagus and viscera of the thorax and abdomen.