Test 61 (head and neck anatomy)

1. The following are true with regard to the anatomy of the tongue:

a. the tongue develops from the first, third and fourth 
    pharyngeal arches

b. the intrinsic muscles of the tongue are derived from the 
    occipital myotomes

c. the hypoglossal nerve supplies all the muscles of the 
    tongue

d. the parasympathetic secretomotor fibres to the 
    posterior third of the tongue is derived from the otic 
    ganglion

e. the sulcus terminalis divides the tongue into anterior 
    two-third and posterior one-third

Answera.T    b.T   c.F   d.T   e.T
The hypoglossal nerve supplies all the muscles of the tongue except the palatoglossus which is supplied by the vagus nerve
 

2. The effect of severing the sympathetic nerve to one side of an adult 
    head will result in:

a. ipsilateral arteriolar vasoconstriction

b. ipsilateral decreased sweating

c. decreased accommodation

d. decreased tear production

e. decreased iris pigmentation

Answera.F    b.T    c.F   d.F    e.F
Vasodilatation occurs with sympathetic nerve damage. Tear production and accommodation are controlled by the parasympathetic nervous system.
Iris pigmentation is not affected in adult but in congenital sympathetic denervation, iris hypopigmentation can occur.

3. The vertebral artery:

a. is derived from the carotid artery

b. enters the skull through the foramen magnum

c. gives off the posterior inferior cerebellar artery

d. contains a plexus of preganglionic sympathetic nerve on 
    its wall

e. is anterior to the spinal accessory nerve as it enters the 
   skull

Answera.F    b.T    c.T   d.F    e.T
It is derived rom the subclavian artery.
It contains a plexus of postganglionic sympathetic nerve derived from the stellate ganglion

4. The following are true about the thyroid gland:

a. its vascular supply is derived solely from the external 
    carotid artery

b. it is firmly attached to the larynx

c. it contains an isthmus which overlies the fourth to sixth 
    tracheal ring

d. it is covered by pretracheal fascia

e. it increases in size during pregnancy

Answera.F    b.T    c.F    d.T    e.T
The thyroid gland is supplied by branches of the subclavian and external carotid arteries.
The isthmus lies over the second to fourth tracheal rings.
 

5. Regarding the ear:

a. the external ear is supplied by a sensory branch of the 
    facial nerve

b. the auditory canal can be straightened by pulling the 
    pinna upwards and backwards

c. the tympanic membrane is supplied by the vagus nerve

d. the auditory canal is supplied by the glossopharyngeal 
    nerve

e. the malleus lies media to the tympanic membrane.

Answera.T    b.T   c.T    d.F   e.T
The external ear is supplied by a branch of the facial nerve. Therefore, in Ramsey-Hunt's syndrome, vesicles can be seen on the pinna.
The auditory canal is supplied by the auriculotemporal nerve and vagus nerve. 
The outer surface of the tympanic membrane is supplied by the vagus nerve and the inner surface by the glossopharyngeal nerve.