chapter 16

Identify the fluid filled space between the cornea and iris.

Anterior chamber

Blindness caused by glaucoma is the result of increased pressure in the anterior segment of the eye and compression of the optic nerve. What is the correct pathway for aqueous humor production and drainage into the anterior segment of the eye?

Ciliary processes, posterior chamber, pupil, anterior chamber, scleral venous sinus

The iris divides the eye into the anterior and posterior segments.

False

Identify the structure that regulates the amount of light entering the posterior segment of the eye.

Iris

Which is true about a retinal detachment?

It can result from a blow to the eye.

Which of these statements concerning vitreous humor is FALSE?

It is renewed continuously.

Why is the sense of touch not considered a "special sense"?

Its receptors are widespread throughout the body.

In describing the distribution of photoreceptors on the retina, which of the following statements is true?

Rod cells are more numerous and more light sensitive than cones, which allows for gray, fuzzy vision in dim light.

What is strabismus?

The affected eye is turned medially or laterally with respect to the normal eye; results from weakness or paralysis of extrinsic eye muscles.

Identify the areas that are filled with aqueous humor.

The anterior and posterior chambers

When the lens of the eye bulges for close vision, which of the following happens?

The ciliary muscles contract.

Why do corneal transplants have minimal risk of rejection?

The cornea is avascular and has minimal exposure to the recipient's immune system.

What layer of the retina undergoes age-related degeneration and is the primary cause of the condition.

The pigmented layer

Which of the following statements does not correctly describe the spiral organ of Corti?

The tectorial membrane bends with vibrations, whereas the basilar membrane is rigid and fixed.

You are listening to music on your iPod at a very loud volume. What happens in your middle ear to protect the hearing receptors in your inner ear?

The tensor tympani and stapedius muscles contract reflexively.

What is the function of the outer hair cells in the spiral organ (organ of Corti)?

They are involved with actively tuning the cochlea and amplifying the signal.

Both the choroid and the retina __________.

absorb light and prevent it from scattering within the eye

The middle ear cavity is normally filled with

air

The transmission of sound vibrations through the external acoustic meatus occurs chiefly through

air

What axons decussate in the optic chiasma?

axons from the medial half of each eye

Which cells divide to replace the gustatory cells that are routinely damaged during eating?

basal epithelial cells

In hyperopic (farsighted) eyes, diverging light rays from nearby objects cause the focal point to occur __________, resulting in __________ objects to appear blurry.

behind the retina / nearby

Hair cells are receptor cells for

both hearing and equilibrium

Which of the following lies closest to the anterior pole of the eye?

center of the cornea

Which response does NOT occur in the eye to aid in viewing near objects?

change in shape of the cornea

Melanin-containing layer of the eye's vascular tunic.

choroid

Endolymph-filled structure containing receptors for hearing.

cochlear duct

Part complete Receptors for hearing are located in the

cochlear duct

Transparent mucous membrane covering the inner surface of the eyelid.

conjunctiva

Transparent structure of the eye containing regularly aligned collagen fibers.

cornea

what is the transparent portion of the fibrous layer?

cornea

Which cranial nerve conveys sensory gustatory impulses from the posterior one-third of the tongue?

cranial nerve IX

Which of the following would not be associated with strabismus?

damage to the optic nerve

Through which cranial bone do the nerve fibers of the olfactory nerve pass?

ethmoid

Which cranial nerve does not innervate the extrinsic eye muscles?

facial

Lacrimal fluid is produced by the lacrimal sac in the medial canthus of the eye.

false

Light entering the eye passes first to the rod and cone cells, then to bipolar cells, and finally to ganglion cells adjacent to the pigmented retina.

false

The pupil can adjust its size independent of the iris.

false

The scala vestibuli is adjacent to the round window, whereas the scala tympani is adjacent to the oval window

false

The superior oblique muscle of the eye enables the eye to look upward and laterally.

false

The tips of cochlear hair cells are embedded in the basilar membrane.

false

There are three layers of neurons in the retina. Which of the following neurons have axons that form the optic nerves?

ganglion cells

Sensory receptor for taste.

gustatory epithelial cells

Ordinarily, it is not possible to transplant tissues from one person to another without rejection, yet corneas can be transplanted with impunity. This is because the cornea

has no blood supply, except around the periphery

Farsightedness is more properly called

hyperopia

Hyperopia and presbyopia may have some features in common, but a key difference between these two conditions is that

in hyperopia the lens can accommodate, but in presbyopia it cannot.

Which of these extrinsic eye muscles depresses the eye and turns it medially?

inferior rectus

The superior oblique muscle turns the eye both laterally and

inferiorly

Each of the following structures participates in bending of light entering the eye except the

iris

The modiolus __________.

is a pillar of bone shaped like a screw whose tip lies at the apex of the cochlea

What structure is handled by an "eye bank"?

just the cornea

The eyelids house all of the following except the

lacrimal sac

The first "way station" (relay nucleus) in the visual pathway from the eye, after there has been partial crossover of the fibers in the optic chiasma, is the

lateral geniculate nucleus.

Clouding of which of the following structures would lead to a clinical condition known as a cataract?

lens

Which structure divides the internal chamber of the eye into anterior and posterior segments?

lens

The muscle that opens the eye is the

levator palpebrae superioris

Odors may elicits a variety of emotions if these impulses are relayed through the __________.

limbic system

Which portion of ear contains ear ossicles?

middle

Filaments of the olfactory receptor cells synapse with these cells of the olfactory tract.

mitral cells

Nearsightedness is more properly called

myopia

Where do tears drain?

nasal cavity

The center for vision in the cerebral cortex is located in the

occipital lobe

Damage to which cranial nerve would be suspected if a light aimed at the eye did not initiate the pupillary light reflex to cause pupil constriction?

oculomotor nerve

An essential part of the maculae involved in static equilibrium is/are the

otoliths

Calcium carbonate crystals of the macula.

otoliths

Membrane attached to the stapes.

oval window

The stapes vibrates against the __________.

oval window

The ora serrata is a

part of the retina.

Nerve axons from the lateral portion of each retina

pass posteriorly without crossing over at the chiasma.

The equilibrium pathway transmits most of its information to lower brain centers because the __________.

pathway responds to loss of balance and must be rapid and reflexive to prevent injury

The bony labyrinth is located in which portion of the temporal bone?

petrous

Abraham spoke so softly that Jason rolled a piece of paper into a funnel shape and put one end into his external auditory canal to signal Abraham to speak up. Abraham then shouted that a certain anatomical structure serves exactly the same function as Jason's paper funnel. That structure is the

pinna

A 58-year-old gentleman noted that he was having problems reading cross-word puzzles. The letters appeared fuzzy and he guessed that he needed reading glasses. What condition does he have?

presbyopia

What structure regulates the amount of light passing to the visual receptors of the eye?

pupil

The cristae in the inner ear contain the receptors for

rotational equilibrium

What is the specific location of the inner and outer hair cells for hearing?

scala media (cochlear duct)

Of the following structures, which is the only one that contains perilymph (instead of endolymph)?

scala tympani

The oval window of the ear is connected directly to which passageway?

scala vestibuli

Which portion of the eye is covered by conjunctiva?

sclera

The cristae ampullares in the inner ear are located in the

semicircular ducts

The ossicle that is shaped like the stirrup of a saddle is the

stapes

In addition to sending visual information to the primary visual cortex, some axons from the optic tracts go to the __________.

suprachiasmatic nucleus in the hypothalamus to regulate daily biorhythms

The oil component found in tears is produced by the

tarsal glands

Microvilli from gustatory cells project through this structure.

taste pore

The scala tympani __________.

terminates at the round window at the base of the cochlea and is filled with perilymph

In which region of the brain do the axons of the optic tract synapse?

thalamus

The difference between the membranous ampulla and cupula of the ear is that

the ampulla contains the crista ampullaris, which consists of hair cells and a cupula.

Which of the following areas has the highest concentration of cones?

the fovea centralis

Which of the following structures in the eye are pigmented?

the retina

Another name for the ciliary zonule is

the suspensory ligament of the lens.

Conduction deafness results from an inability of vibrations to pass to the inner ear.

true

The cone-filled region of the retina surrounding the fovea centralis is called the macula lutea.

true

The incus bridges the gap between the stapes connected to the oval window and the malleus connected to the tympanic membrane.

true

The vestibule of the ear lies between the semicircular canals and the cochlea.

true

Which of the following membranes is not part of the cochlea?

tympanic

__________, which means "deliciousness" in Japanese, was recognized as a fifth basic taste in the 1980s.

umami

Olfactory sensory neurons __________.

undergo replacement throughout life

Along with the saccule, this structure senses linear acceleration.

utricle

Bony labyrinth structure containing the utricle and saccule.

vestibule

Fluid filling the posterior segment of the eye.

vitreous humor