Exam 3 Chapter 16

Question 1

What type of tissue forms the receptor cells for taste?

Answer 1

epithelial cells

Question 2

What type of cell are the olfactory receptors?

Answer 2

bipolar neurons

Question 3

What happens when bipolar neurons are damaged?

Answer 3

they are replaced

Question 4

What is conjunctiva and where is it located?

Answer 4

transparent mucous membrane that covers the inner surfaces of the eyelids and the anterior surface of the eye

Question 5

What muscle is not functioning in a person whose eye turns medially?

Answer 5

lateral rectus

Question 6

What nerve innervates lateral rectus?

Answer 6

abducens (VI)

Question 7

Differentiate the cornea from the choroid with reference to the location, structure, and function of each.

Answer 7

Corea: fibrous layer of the eye
- composed of dense connective tissue sandwiched between two layers of epithelium
Choroid: middle vascular layer of the eye
- blood vessels nourish the eye and its pigment absorb light

Question 8

What portion of the visual field is lost in a person with degeneration of the macula lutea?

Answer 8

straight ahead

Question 9

What is the aqueous humor? Where is it located? What are its functions?

Answer 9

Clear watery fluid that fills the anterior segment
- supplies nutrients and oxygen to the avascular lens and cornea
- maintains constant intraocular pressure

Question 10

In a normal eye, when the lens accommodates for viewing close objects, does it become rounder or more oval in shape?

Answer 10

rounder

Question 11

Why do middle-aged to older adults develop difficulty focusing on close objects?

Answer 11

Lens become less elastic as we age.
- accommodation for viewing close objects requires elasticity of the lens

Question 12

Trace the visual pathway from the medial half of the retina of the right eye to the cerebral cortex.

Answer 12

1) Axons from ganglion cells from the medial half of the retina extend through the right optic nerve.
2) Passes through the optic chiasma to the left optic tract
3) Synapse in the left lateral geniculate nucleus of the thalamus with neurons that extend via the optic radiation to the left primary visual cortex

Question 13

What structure separates the external acoustic meatus from the middle ear cavity?

Answer 13

tympanic membrane (ear drum)

Question 14

Name the four openings or holes into the middle ear cavity.

Answer 14

• pharyngotympanic tube
• round window
• oval window
• mastoid antrum

Question 15

Which auditory ossicle abuts the tympanic membrane?

Answer 15

malleus

Question 16

What is the difference between the membranous labyrinth and the bony labyrinth of the internal ear?

Answer 16

membranous: continuous series of membranous sacs and ducts filled with endolymph (contains sensory receptors for hearing and equilibrium)
bony: cavity within petrous portion of the temporal bone that surrounds the membranous labyrinth

Question 17

Where is perilymph located within the cochlea?

Answer 17

fills the cavity of the bony labyrinth or the cochlea, scala vestibuli, and scala tympani

Question 18

Where in the cochlear duct is the vestibular membrane located?

Answer 18

roof of the cochlear duct

Question 19

Where in the cochlear duct is the basilar membrane located?

Answer 19

forms the floor

Question 20

Where in the cochlear duct is the tectorial membrane located?

Answer 20

sits atop the sensory hair cells

Question 21

Vibrations in which membrane stimulate the hair cells of the spiral organ?

Answer 21

tectorial membrane

Question 22

Which sensory receptors monitor stationary head position and linear movements of the head? Where are these receptors located?

Answer 22

maculae of the utricle and saccule

Question 23

What type of deafness results from damage to the cells of the spiral ganglion?

Answer 23

sensorineural deafness

Question 24

What brain regions receive input from the vestibular nerves and process information on equilibrium?

Answer 24

vestibular nuclei of the medulla and cerebellum

Question 25

What sense is involved in sensory impulses transmitted over the facial, glossopharyngeal, and vagus nerves?

Answer 25

taste

Question 26

What part of the eye is white, tough, and opague?

Answer 26

sclera

Question 27

Where does the transmission of sound vibrations through the internal ear occur?

Answer 27

fluid

Question 28

Of the neurons in the retina, which form the optic nerve?

Answer 28

ganglion neurons

Question 29

In the brain, where is taste information transmitted through?

Answer 29

insula lobe, solitary nucleus, thalamus

Question 30

Where does conduction of sound from the middle ear to the internal ear occur?

Answer 30

Vibration of stapes in the oval window

Question 31

Where are the receptors for static equilibrium that report the position of the head in space relative to the pull of gravity located?

Answer 31

maculae

Question 31

What is part of the spiral organ?

Answer 31

tectorial membrane, inner hair cells, outer hair cells

Question 32

What would be affected from the paralysis of a medial rectus muscle?

Answer 32

refraction

Question 33

What's the order that a light ray passes through the refractory structures of the eye?

Answer 33

cornea, aqueous humor, lens, vitreous humor

Question 34

What extrinsic eye muscles originate from the common tendinous ring?

Answer 34

superior oblique, superior rectus, inferior rectus

Question 35

What are some basic taste sensation?

Answer 35

bitter, sour, sweet

Question 36

What and where is the optic disc and why is it important?

Answer 36

Where optic nerve fibers exit the eye (blind spot because lack of photoreceptors) - on the retina - understanding visual field deficits and diagnosing conditions (can indicate damage or pressure in the eye)

Question 37

Name two special senses whose receptor cells are replaced throughout life, and two special senses whose receptor cells are replaced so slowly that there can be no functional regeneration.

Answer 37

Can be replaced: Taste and smell Can't be replaced: Hearing and vision

Question 38

Describe the function and the innervation of both the sphincter and dilator muscles of the pupil.

Answer 38

Sphincter function: constricts pupil to regulate light entry Sphincter innervation: parasympathetic fibers of the oculomotor nerve (III) Dilator muscle function: dilates the pupil to allow more light in Dilator muscle innervation: sympathetic nervous system