lecture 11

Question 1

If your eye rests towards your nose (medially), a lesion may be present on _______ cranial nerve and affects the _______ muscle

Answer 1

abducens, lateral rectus

Question 2

Which cranial nerves control movements of the eyeball?

Answer 2

oculomotor (3), trochlear (4), and abducens (6)

Question 3

Which cranial nerve has a somatic motor function primarily involved in moving the upper eyelid and eyeball and an autonomic function involved in iris muscle contraction?

Answer 3

oculomotor nerve

Question 4

Facial movement is primarily controlled by ____ nerve, while sensation from the face is primarily determined by ____ nerve.

Answer 4

facial, trigeminal

Question 5

A patient shows no effect when a light shines in the right eye, but shining a light into the left eye causes both pupils (right and left) to constrict. This could be caused by a lesion on the ______ nerve.

Answer 5

optic nerve

Question 6

Which is the correct order of events of sound transmission through the ear?

1. sound waves strike the eardrum
2. the ear ossicles vibrate
3. hair cells of the organ of Corti vibrate
4. the perilymph in the cochlea moves
5. sound waves enter the external auditory canal

Answer 6

5, 1, 2, 4, 3,

Question 7

The hair cells responsible for hearing are located on the ________; their hair bundles are embedded in the ________

Answer 7

basilar membrane, tectorial membrane

Question 8

what is the correct pathway of sound waves from the auricle to the spiral organ of Corti?

Answer 8

external auditory canal → tympanic membrane → maleus → incus → stapes → oval window → perilymph

Question 9

What ear structure vibrates back and forth when sound waves strike?

Answer 9

tympanic membrane

Question 10

Pressure waves in endolymph cause the ____ basilar membrane to vibrate, which moves hair cells of the ____ spiral organ. The hair cells touch the ____ tectorial membrane which bends the stereocilia and generates nerve impulses in first-order neurons.

Answer 10

basilar membrane, spiral organ, tectorial membrane

Question 11

Which structures contain endolymph?

Answer 11

saccule, utricle and cochlear duct

Question 12

Nerve impulses for the sense of hearing are initiated in the spiral organ (organ of Corti) and then travel through the _____ to the cochlear nuclei in the _____.

Answer 12

cochlear branch of CN8, pons

Question 13

Select the correct order for the neural pathway from the inner ear to the brain.

1. inferior colliculus
2. cochlear branch nerve fibers of cranial nerve VIII
3. superior olivary nucleus in pons
4. hair cells in spiral organ
5. medial geniculate nucleus in thalamus
6. primary auditory cerebral cortex
7. cochlear nuclei in medulla oblongata

Answer 13

4, 2, 7, 3, 1, 5, 6