Describe The Functions Of The Cranial Nerves II, III, IX And X Flashcards
What type of nerve is II?
II cranial nerve is the optic nerve.
Is II Optic cranial nerve sensory or motor?
The Optic nerve is a sensory nerve only.
Is the II Optic cranial nerve sympathetic or parasympathetic?
The Optic cranial nerve has no parasympathetic fibres so is sympathetic.
What is the II Optic Cranial Nerve linked to?
It is associated with the sense of vision, it is actually a brain tract because it develops as an outgrowth.
What is the III Cranial nerve?
The III cranial nerve is the oculomotor.
Is the III oculomotor Cranial nerve motor or sensory?
It is mainly motor, however it has a small sensory function.
What type of fibres does the III oculomotor cranial nerve contain.
It contains parasympathetic fibres.
What is the purpose of the III Oculomotor cranial nerve?
The oculomotor nerve is responsible for raising eyelids, moving eyes, adjusting amount of light entering, focusing of lenses.
What is the purpose of extrinsic muscles?
Extrinsic muscles move the eyeball in its orbits.
How many of the six extrinsic muscles are controlled by the III oculomotor cranial nerve?
Four of the six extrinsic muscles are controlled by the oculomotor.
In the III Oculomotor cranial nerve parasympathetic motor fibre reaches where?
The parasympathetic motor fibre reaches the sphincter papillae to make the pupil constrict.
In the III oculomotor cranial nerve what muscle controls the lens shape?
The muscle controlled, is the ciliary muscle.
In the III oculomotor cranial nerve what do the sensory fibres do?
The sensory fibres within the III oculomotor cranial nerve is associated with muscle condition.
Which cranial nerve is IX?
IX cranial nerve is the glossopharyngeal.
The cranial nerve IX Glossopharyngeal has what fibres linked to it?
IX glossopharyngeal cranial nerve has both parasympathetic and sympathetic fibres attached to it.
In the glossopharyngeal IX cranial nerve what do the parasympathetic fibres do?
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.
In the IX glossopharyngeal cranial nerve, what does the sensory fibre do?
The sensory fibres transmit impulses from the pharynx, tonsils, posterior tongue and carotid arteries.
Which nerve is the X cranial nerve?
The X cranial nerve is the vagus nerve.
In the X Vagus cranial nerve which type of fibres does it have?
The X vagus, cranial nerve has both sympathetic and parasympathetic fibres.
What is the special fact about the X Vagus, cranial nerve?
It is the only nerve that extends beyond the head and neck reaching the thorax and abdomen.
Within the X Vagus Cranial Nerve what does the somatic motor fibres do?
The somatic motor fibres transmits impulses to muscle used for speech and swallowing.
What type of fibres does the X Vagus cranial nerve have?
It has both parasympathetic and sympathetic fibres.
Within the X Vagus cranial nerve what is the autonomic motor fibres function?
They transmit impulses to the heart, smooth muscles, thoracic and abdominal glands.
Within the X Vagus cranial nerve, what is the sensory fibres function?
The sensory fibres transmit impulses from the pharynx, larynx, oesophagus and viscera of the thorax and abdomen.
