Deck 15: The Special Senses

Question 1

Precision of eye movement is due to the fact that extrinsic eye muscle motor units typically innervate 8 to 12 muscle cells and in some cases as few as 2 or 3 muscle cells.

Answer 1

True

Question 2

Static equilibrium involves the sensation of linear acceleration as well as changes in head rotation.

Answer 2

False

Question 3

Ciliary muscles are considered voluntary, skeletal muscle.

Answer 3

False

Question 4

When we move from darkness to bright light, retinal sensitivity is lost, but visual acuity is gained.

Question 5

The structure that allows equalization of the pressure in the middle ear with the atmospheric pressure is the external auditory meatus.

Question 6

The function of the lens of the eye is to allow precise focusing of light on the retina.

Question 7

Vitamin A needed by the photoreceptor cells is stored by the cells of the retina pigmented layer.

Question 8

The fluid contained within the membranous labyrinth is called perilymph.

Question 9

Light passes through the entire thickness of the neural layer of the retina to excite the photoreceptors.

Question 10

Odorants must be volatile to be smelled.

Question 11

Theoretically, an individual born without a middle ear would be able to hear by bone conduction with a hearing aid.

Question 12

Contraction of the ciliary muscle causes the lens to bend the light less.

Question 13

Sour taste receptors are stimulated by hydrogen ions of acidic food substances.

Question 14

Sound is generally perceived in the occipital lobe of the cerebral cortex.

Question 15

In order for sound to reach the spiral organ (of Corti), the auditory ossicles must vibrate the oval window and set the endolymph in motion.

Question 16

The bending of light rays is called reflection.

Question 17

The neural layer of the retina prevents excessive scattering of light within the eye.

Question 18

The anterior chamber of the eye is filled with vitreous humor.

Question 19

The optic disc forms a blind spot where the optic nerve leaves the eyeball.

Question 20

Without a functioning crista ampullaris, the semicircular canals would not function.

Question 21

In a person who is color-blind, which of the following would you most expect to see?

A) absence of green or red cones in their foveae
B) an inability to regenerate 11-cis-retinal after bleaching
C) a loss of their peripheral vision
D) a loss of functions in the rods of their retina

Question 22

Hair cells in the spiral organ of the ear are never replaced.

Question 23

Which of the following best describes the function of the iris?

A) gives the eye its color
B) refracts light through the pupil
C) controls amount of light entering eye
D) adjusts the shape of the lens

Question 24

Overlap in the visual fields of our eyes .

A) leaves a blind spot anterior to the nose and in the lateral fields of vision
B) gives us higher visual acuity for small detail by doubling the number of photoreceptors that are being stimulated
C) is essentially a waste of brain processing for what is essentially the same image
D) allows us to subconsciously estimate the distance of objects based on the different angles the image strikes our two retinas

Question 25

The elasticity of the lens decreases with age. This leads to which of the following?

A) less accommodation of the lenses and difficulty focusing on nearby objects
B) lowered accommodation of the pupillary reflex and blurry vision
C) less light getting to the retina and diminished visual acuity
D) a clouding of the lenses known as a cataract

Question 26

Dancers will use a technique called "spotting" when they perform spins of the body. By holding their head and eyes on a fixed point in front of them as their body spins they reduce the amount of head spinning and this prevents dizziness. Which of the following is the most likely explanation for why this works?

A) This will help to reduce the lateral flection of the head and will prevent hyper polarization or depolarization of the hair cells in the macula.
B) When the eyes send a static vision of stability to the brain, it is tricked into believing the body is still and therefore dizziness will not occur.
C) Reducing the inertia of head spin will reduce the flow of endolymph that deflects the hair cells of the crista ampullaris.
D) This helps keep the motions detected by the eyes congruent (aligned) with the motions sensed by the vestibular apparatus.

Question 27

Paralysis of which eye muscle would prevent the right eye from looking to the left?

A) Medial rectus
B) Inferior rectus
C) Superior rectus
D) Lateral rectus

Question 28

The quality of a sound is based on the atmospheric pressure at the time the sound is generated.

Question 29

Labyrinthitis is a medical condition often caused by a viral infection, resulting in swelling and inflammation of the membranous labyrinth. Which of the following symptoms would you most associate with the condition of labyrinthitis?

A) loss of hearing
B) auditory hallucination
C) loss of balance and dizziness
D) ringing in the ears (tinnitus)

Question 30

Select the statement below that is NOT true with regards to the process of light adaptation.

A) Rhodopsin is uncoupled from light transduction.
B) Visual acuity is diminished.
C) Retinal sensitivity decreases.
D) The activity of rods is reduced by rapid bleaching of rhodopsin.

Question 31

If you shine a light into one eye both pupils will constrict. The best explanation for this is .

A) information from one eye is directly and immediately transferred to the other eye to maintain alignment of the eyes
B) a small portion of light always enters the other eye
C) sensory input from the retinas of both eyes converges at the optic chiasm and information from each eye is delivered to both the left and right sides of the brain
D) This, in fact, does not occur; information from both eyes is always separated.

Question 32

A patient has a loss of hearing in only one ear. Which of the following is likely to be a result?

A) The patient will have increased sensitivity to sound in the unaffected ear.
B) The patient will not be able to localize the origin of sounds.
C) The patient will not be able to track objects with the eye on the same side as the hearing loss.
D) The patient will have a loss of balance with dizziness and vertigo.

Question 33

Humans can smell as many as 10,000 different odors but have significantly fewer types of olfactory receptors. Which of the following is the best explanation for why humans can distinguish so many smells?

A) Taste receptors that are active at the same time influence the subtlety of what we smell.
B) The sensation of a single, distinct smell is a combination of a variety of chemicals that stimulate different combinations of olfactory receptor cells all at once.
C) The belief that we can smell so many different distinct odors is a psychological process referred to as an uncinate fit or olfactory hallucination.
D) The olfactory pathway travels to location in the brain in which memories are formed and we simply mix this new sensory information with old memories.

Question 34

The sensation of loudness or the volume of a sound is detected by _.

A) faster vibration of the basilar membrane resulting in a higher frequency of hair cell stimulation
B) vibration along a greater length of the basilar membrane, stimulating a greater number of hair cells
C) greater movement of the basilar membrane resulting in greater deflection of the hair cells
D) sounds that can travel all the way to the apex of the scala vestibule with enough energy remaining to deflect hair cells

Question 35

Humans can see several thousand shades of color but have cone photoreceptors that are sensitive to only three (perhaps four) wavelengths of light. What is the best explanation for why we see so many colors?

A) Color perception is dependent on the millions of rods as well as cone photoreceptors.
B) Shades of color are purely psychological and learned by association with age, infants only seeing in black and white.
C) Colors are added and enhanced in the primary visual cortex of the brain.
D) Color perception is achieved by activation of various combinations between the three cone types.

Question 36

Which of the following is the best explanation for our perception of color?

A) As many as 100 cones may converge on one ganglion cell.
B) The foveae are densely packed with cones.
C) Rods contain a single kind of visual pigment.
D) Cones come in three types, each sensitive to different wavelengths of light.

Question 37

Nutrients are delivered and waste products are carried away from the cells of the posterior segment of the eye by blood vessels. However, the cells in the cornea and lens (in the anterior segment) are avascular. Which is the best explanation for how these cells are maintained?

A) The aqueous humor is continuously replenished and flows from the ciliary process to drain in the scleral venous sinus.
B) The nutrients and waste products of the anterior segment diffuse into and through the vitreous humor of the posterior segment.
C) These cells, like the cells of the corneal layer of the integument are not living cells.
D) The metabolic activity of these cells is very low. They produce little waste and need few nutrients.

Question 38

As light travels through the eye, it passes through several structures or chambers before reaching the retina. Which list below gives those structures in the correct order?

A) cornea, pupil, lens, anterior chamber, posterior segment
B) cornea, lens, pupil, anterior chamber, posterior segment
C) cornea, pupil, anterior chamber, lens, posterior segment
D) cornea, anterior chamber, pupil, lens, posterior segment

Question 39

Color vision has much greater resolution than night vision (vision that is mostly in shades of gray). Which of the following is the best explanation for why this is so?

A) There are several types of cone photoreceptors, each of which enrich the clarity and resolution of vision.
B) A single cone photoreceptor often connects to a single bipolar cell and a single ganglion cell while as many as 100 rods will converge to a single ganglion cell.
C) There are many more cone photoreceptors in the eye than rod photoreceptors.
D) A larger proportion of the brain's visual cortex is active during the day when our cone photoreceptors are most active.

Question 40

Which of the following is the best explanation of why it is difficult to discriminate the color of an object at night?

A) At night, dilation of pupils stimulates the retina, where more rods are located rather than cones.
B) The foveae are densely packed with cones.
C) Cones come in three types, each sensitive to different wavelengths of light.
D) As many as 100 cones may converge on one ganglion cell.

Question 41

Tom is a 45-year-old male that has lost his ability to hear high frequency sounds. The most likely explanation for this would be .

A) a perforated tympanic membrane
B) a middle ear infection
C) an overgrowth of bony tissue, fusing the ossicles together
D) damage to the hair cells near the oval window in the cochlear duct

Question 42

The oval window is connected directly to which passageway?

A) scala vestibuli
B) pharyngotympanic tube
C) scala tympani
D) external acoustic meatus

Question 43

The receptor for static equilibrium is the .

A) macula
B) semicircular canals
C) cochlear duct
D) utricle

Question 44

Taste buds are NOT found .

A) in filiform papillae
B) lining the buccal cavity
C) in circumvallate papillae
D) in fungiform papillae

Question 45

As sound levels increase in the spiral organ (of Corti), .

A) inner hair cells bend the cilia away from the kinocilium
B) outer hair cells stiffen the basilar membrane
C) inner hair cells stiffen the basilar membrane
D) outer hair cells bend the cilia away from the kinocilium

Question 46

Which of the following types of neurons are replaced throughout adult life?

A) retinal bipolar cells
B) retinal ganglion cells
C) auditory outer and inner hair cells
D) olfactory receptor cells

Question 47

There are three layers of neurons in the retina. The axons of which of these neuron layers form the optic nerves?

A) bipolar cells
B) cone cells
C) rod cells
D) ganglion cells

Question 48

Receptors for hearing are located in the .

A) tympanic membrane
B) cochlea
C) semicircular canals
D) vestibule

Question 49

Bitter taste is elicited by .

A) metal ions
B) hydrogen ions
C) alkaloids
D) acids

Question 50

Which of the following is true about gustatory receptors?

A) The receptors generate an action potential in response to chemical stimuli.
B) Complete adaptation occurs in about one to five minutes.
C) In order for a chemical to be sensed, it must be hydrophobic.
D) All gustatory receptors have the same threshold for activation.

Question 51

Select the correct statement about olfaction.

A) Olfactory adaptation is only due to fading of receptor cell response.
B) Some of the sensation of olfaction is actually one of pain.
C) Olfactory receptors have a high degree of specificity toward a single type of chemical.
D) Substances must be volatile and hydrophobic in order to activate olfactory receptors.

Question 52

What is the main function of the rods in the eye?

A) accommodation for near vision
B) color vision
C) vision in dim light
D) depth perception

Question 53

Seventy percent of all sensory receptors are located in the .

A) skin
B) ears
C) eye
D) nose

Question 54

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

A) lateral geniculate body of the thalamus
B) temporal lobe
C) visual cortex
D) superior colliculi

Question 55

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

A) has no nerve supply
B) is not a living tissue
C) has no blood supply
D) does not contain connective tissue

Question 56

Which of the following structures is NOT part of the external ear?

A) external acoustic meatus
B) pinna
C) tympanic membrane
D) pharyngotympanic tube

Question 57

The ability to clearly see objects at a distance but not close up is properly called .

A) myopia
B) hyperopia
C) hypopia
D) presbyopia

Question 58

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

A) cornea
B) aqueous humor
C) iris
D) lens

Question 59

Nerve fibers from the medial aspect of each eye .

A) go to the superior colliculus only
B) divide at the chiasma, with some crossing and some not crossing
C) pass posteriorly without crossing over at the chiasma
D) cross over to the opposite side at the chiasma

Question 60

Which of the following describes a response of the eye to sympathetic stimulation?

A) pupil dilation
B) ciliary muscle relaxation
C) pupil constriction
D) ciliary muscle contraction

Question 61

In the visual pathways to the brain, the optic radiations project to the .

A) optic chiasma
B) medial retina
C) lateral geniculate body
D) primary visual cortex

Question 62

Which of the following types of receptors are located in the mouth?

A) chemoreceptors, mechanoreceptors, thermoreceptors, and nociceptors
B) thermoreceptors, mechanoreceptors, and nociceptors only
C) chemoreceptors only
D) chemoreceptors, thermoreceptors, and nociceptors only

Question 63

Which statement about malnutrition-induced night blindness is most accurate?

A) The impaired vision is caused by reduced cone function.
B) Visual pigment content is reduced in cones more than rods.
C) Vitamin supplements can reverse degenerative changes.
D) The most common cause is vitamin D deficiency.

Question 64

Conscious perception of vision probably reflects activity in the .

A) occipital lobe of the cortex
B) superior colliculus
C) thalamus
D) chiasma

Question 65

The blind spot of the eye is caused by _ .

A) an absence of photoreceptors where the optic nerve leaves the eye
B) an absence of cones in the foveae
C) more rods than cones within the retina
D) the macula lutea interrupts the nerve pathway

Question 66

Visual inputs to the serve to synchronize biorhythms with natural light and dark.

A) superior colliculi
B) pretectal nuclei
C) lateral geniculate body
D) suprachiasmatic nucleus

Question 67

Motion sickness seems to _.

A) result from mismatch between visual and vestibular inputs
B) respond best to medication that "boosts" vestibular inputs
C) respond best to medication taken after salivation and pallor begins
D) result from activation of nausea centers in the brain stem

Question 68

A patient who has experienced previous jaw and face trauma now reports difficulty tasting with the tip of her tongue. Which cranial nerve was likely damaged in that injury?

A) Facial (VII)
B) Glossopharyngeal (IX)
C) Hypoglossal (XII)
D) Trigeminal (V)

Question 69

Which pairing of terms is incorrectly related?

A) amplitude of a sound: intensity of the sound
B) frequency of sound waves: loudness of the sound
C) quality of a sound: frequency of the sound
D) frequency of sound waves: number of wavelengths

Question 70

Most newborns _.

A) are myopic
B) often use only one eye at a time
C) produce more tears when they cry than a toddler
D) see in tones of red and green only

Question 71

Dark adaptation _.

A) involves accumulation of rhodopsin
B) primarily involves improvement of acuity and color vision
C) is much faster than light adaptation
D) results in inhibition of rod function

Question 72

Which of the following taste sensations is incorrectly matched to the chemicals that produce it?

A) sweet-organic substances such as sugar and some lead salts
B) umami-triglycerides and fatty acids
C) salty-metal ions
D) sour-acids
E) bitter-alkaloids

Question 73

During dark adaptation, .

A) the cones are activated
B) the rate of rhodopsin breakdown is accelerated
C) rhodopsin accumulates in the rods
D) the sensitivity of the retina decreases

Question 74

Which of the following could NOT be seen as one looks into the eye with an ophthalmoscope?

A) fovea centralis
B) optic disc
C) macula lutea
D) optic chiasma

Question 75

The cells of the retina in which action potentials are generated are the .

A) amacrine cells
B) rods and cones
C) ganglion cells
D) bipolar cells

Question 76

Tinnitus, vertigo, and gradual hearing loss typify the disorder called .

A) motion sickness
B) strabismus
C) conjunctivitis
D) Ménière's syndrome

Question 77

The first vestiges of eyes in the embryo are called .

A) optic cups
B) optic vesicles
C) mesenchyme
D) optic discs

Question 78

Which best describes the function of olfactory cilia?

A) increase surface area of neurons receptive to airborne chemicals
B) trap inhaled particulates before air reaches lungs
C) help move air through nasal passages
D) help transport mucus toward nasopharynx

Question 79

What is a modiolus?

A) bone around the cochlea
B) a bony area around the junction of the facial, vestibular, and cochlear nerves
C) bone in the center of a semicircular canal
D) a bone pillar in the center of the cochlea

Question 80

The only special sense NOT fully functional at birth is the sense of .

A) vision
B) hearing
C) equilibrium
D) taste
E) smell