A&P Chapter 15

Even though we have two eyes, why do we normally see only one image? -Information from each eye goes to both hemispheres for processing. -Only one eye views an image at a time. -Only the dominant eye (which corresponds to the dominant hand) is used in vision. -One eye processes close images. The other eye processes images at a distance.

Which of the following is NOT a requirement for something to be tasted? -The tastant must contact the basal epithelial cells of the taste buds. -The tastant must diffuse into a taste pore. -The tastant must contact gustatory hairs. -The tastant must dissolve in saliva.

The final step in perceiving sound is __________. -the tympanic membrane vibrates -the cochlear hair cells are stimulated -the auditory cortex is stimulated -the cochlear nerve is stimulated

Which of the following is true of receptors for dynamic equilibrium? -The receptors for dynamic equilibrium are called maculae. -The receptors for dynamic equilibrium are located in the vestibule of the ear. -The receptors for dynamic equilibrium respond to rotational forces. -The receptors for dynamic equilibrium are not stimulated by head movement.

Which of the following would be the LEAST likely to be associated with the development of motion sickness? -driving rapidly over winding roads -reading a book while being a passenger in a car -having a non-functional vestibular apparatus -taking a ride in a Ferris wheel

If a chalazion interferes with glandular secretion, the immediate outcome would be ______. -the impairment of ciliary gland activity -the loss of eyelash hairs -friction on the anterior surface of the eye -All of the listed responses are correct.

When a person's cold is accompanied by "watery eyes," there is reduced flow of lacrimal fluid directly into the ______. -lacrimal glands -lacrimal canaliculi -lacrimal sac -lacrimal puncta

Which of the following nerves would you predict is NEVER involved in the development of strabismus? -oculomotor (III) -trochlear (IV) -trigeminal (V) -abducens (VI)

If retinal detachment occurs in the macula lutea, one can predict that there would be a significant loss of ______. -color vision -dim-light vision -vision of objects in the peripheral regions of the visual field -All of the listed responses are correct.

In theory, cataracts could be prevented by invention of a treatment that would ______. -increase diffusion rates within the lenses -promote the growth of new blood vessels into the lenses -enhance the production of more crystallins -cause the lens capsules to become more vascularized

Which structure provides the vascular support for the eye? -the ciliary body -the choroid -the aqueous humor -the cornea

You want to look up and to your right. Which extrinsic eye muscles would be the most active in each eye? -right eye: superior oblique left eye: superior rectus -right eye: superior rectus left eye: inferior oblique -right eye: superior rectus left eye: superior rectus -right eye: inferior oblique left eye: superior rectus

Ciliary muscles are considered voluntary, skeletal muscle. True False

Baby Susie's pediatrician notices that one of her eyes rotates outward and that she does not appear to be using it for vision. What is her condition, and what does the pediatrician recommend? -Susie has strabismus. The doctor's recommendations are for eye exercises and/or placing a patch over the unaffected eye; in severe cases, the condition may require surgery. -Susie has diplopia. The doctor's recommendations are for glasses or contact lenses, or laser surgery to correct the problem. -Susie has astigmatism. The doctor's recommendations are for glasses or contact lenses, or laser surgery to correct the problem. -Susie has strabismus. The doctor's recommendations are for eye exercises and/or placing a patch over the affected eye; in severe cases, the condition may require surgery. -Susie has astigmatism. The doctor's recommendations are for eye exercises and/or placing a patch over the affected eye; in severe cases, the condition may require surgery.

Ling, a 75-year-old grandmother, complained that her vision was becoming obscured. Upon examination by an ophthalmologist she was told she had cataracts. What are cataracts, how do they occur, and how are they treated? -A cataract is a clouding of the cornea. Some cataracts are congenital, but most are due to age-related hardening and thickening of the lens, diabetes mellitus, or exposure to UV rays over time. A corneal transplant can be performed to replace the damaged cornea. -A cataract is a clouding of the lens. Some cataracts are congenital, but most are due to age-related hardening and thickening of the lens, diabetes mellitus, or exposure to UV rays over time. The lens can be removed and replaced with an artificial lens. -A cataract is increased intraocular pressure. This occurs when drainage of the aqueous humor is blocked. They are treated with eyedrops that increase the rate of aqueous humor drainage or decrease its production. -A cataract occurs when there are unequal curvatures in different parts of the cornea or lens. This is a congenital condition. Specially ground lenses or laser surgical procedures are used to correct this problem.

A nurse is administering Pilocarpine eye drops. The nurse instructs the patient to press on the nasolacrimal duct for 30 seconds because the medication can have some systemic side effects, such as affecting the heart rate. What is the rationale for pressing on the nasolacrimal duct? -Applying gentle pressure to the nasolacrimal duct reduces secretions from the lacrimal gland, preventing the drug from being washed away quickly. -Applying gentle pressure to the nasolacrimal duct prevents the delivery of the drug to the nasal mucosa and general circulation, where it could affect heart rate. -Applying gentle pressure to the nasolacrimal duct enhances the absorption of the eye drops into the eye. -Applying gentle pressure to the nasolacrimal duct reduces secretions from the tarsal glands, preventing the drug from being washed away quickly. -Applying gentle pressure to the nasolacrimal duct diverts the medication around the entire surface of the eye, so that it isn't washed away quickly.

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 ________. -is not a living tissue -has no nerve supply -has no blood supply -does not contain connective tissue

Seventy percent of all sensory receptors are located in the ________. -ears -eye -nose -skin

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

Which of the following statements is true? -Contraction of the ciliary muscles is required for myopic individuals to clearly see distant objects. -Relaxation of the ciliary muscles is required for hyperopic individuals to clearly see nearby objects. -Contraction of the ciliary muscles is required for hyperopic individuals to clearly see distant objects. -All of the listed responses are true.

Atropine eye drops are used to temporarily paralyze the accommodation reflex and as a long-lasting pupil dilating agent, or mydriatic. What action causes the dilation effect? -increased acetylcholine binding by sphincter pupillae muscle muscarinic receptors -enhanced parasympathetic response by intrinsic eye muscles -blocked contraction of sphincter pupillae muscle -decreased contraction of dilator pupillae muscle

Choose the correctly paired terms. -nyctalopia: night blindness -myopia: farsightedness -astigmatism: clouding of the lens -hyperopia: nearsightedness

In a 30 year old man who has red-green color blindness, light having a wavelength of 530 nm is perceived as being green. This man ______. -cannot easily detect green light due to the absence of red cones -cannot easily detect green light due to the absence of green cones -perceives that red light has a red color -perceives that red light has a green color

Which of the following statements is FALSE? -Vitamin A supplements can sometimes cure nyctalopia because vitamin A can be converted into retinal. -Nyctalopia affects vision in the fovea centralis, resulting in impaired vision. -Retinitis pigmentosa is a disorder in which the discs released from rods are not properly phagocytized. -All of the listed responses are false.

Which photoreceptors respond to very dim light? -green cones -rods -red cones -blue cones

As light hits the retina, the first structure the light encounters is a rod or a cone. True False

Which of the following is the best explanation of why it is difficult to discriminate the color of an object at night? -Rods contain a single kind of visual pigment. -Cones come in three types, each sensitive to different wavelengths of light. -The foveae are densely packed with cones. -As many as 100 cones may converge on one ganglion cell.

Photoreceptors are modified neurons. However, they differ from most neurons in the fact that ________. -photoreceptors are sensitive to energy changes in the external environment -photoreceptors do not release neurotransmitters -photoreceptors will hyperpolarize when stimulated -photoreceptors do not have fluctuations in membrane potential

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? -There are many more cone photoreceptors in the eye than rod photoreceptors. -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. -A larger proportion of the brain's visual cortex is active during the day when our cone photo receptors are most active. -There are several types of cone photoreceptors, each of which enrich the clarity and resolution of vision.

Dark adaptation ________. -is much faster than light adaptation -involves accumulation of rhodopsin -results in inhibition of rod function -primarily involves improvement of acuity and color vision

The cells of the retina in which action potentials are generated are the ________. -amacrine cells -rods and cones -bipolar cells -ganglion cells

During dark adaptation ________. -the sensitivity of the retina decreases -the cones are activated -rhodopsin accumulates in the rods -the rate of rhodopsin breakdown is accelerated

Which of the following is true about photoreceptors? -In dim light, images are focused directly on the rods in the fovea centralis. -Three types of color-sensitive photoreceptors exist: red, green, and yellow. -Rods absorb light throughout the visual spectrum but confer only gray tone vision. -If all cones are stimulated equally, all colors are absorbed by the cones and the color perceived is black.

Which part of the visual pathway is responsible for our daily biorhythms? -suprachiasmatic nucleus -superior colliculus -pretectal area -visual cortex

Damage to the medial portion of the optic chiasm, cause by a pituitary tumor, would lead to __________. -blindness in the left half of the visual field -loss of peripheral vision -loss of central vision -blindness in the right half of the visual field

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

Nerve fibers from the medial aspect of each eye ________. -divide at the chiasma, with some crossing and some not crossing -pass posteriorly without crossing over at the chiasma -go to the superior colliculus only -cross over to the opposite side at the chiasma

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 ________. -lateral geniculate body of the thalamus -superior colliculi -temporal lobe -visual cortex

Visual processing in the thalamus does not contribute significantly to ________. -night vision -depth perception -movement perception -high-acuity vision

The only special sense not fully functional at birth is the sense of ________. -vision -hearing -smell -taste -equilibrium

Rubella infection during early pregnancy may cause damage to the embryo's ______. -optic cups -optic vesicles -lens vesicles -All of the listed responses are correct.

Which middle ear ossicle is attached to, and transmits vibratory motion to, the oval window? incus malleus stapes anvil

Which portion of the ear is responsible for sound transduction? the vestibule the ossicles the cochlea the tympanic membrane

How many ossicles are found in the ear? two three four five

What is a modiolus? -a bone pillar in the center of the cochlea -a bony area around the junction of the facial, vestibular, and cochlear nerves -bone around the cochlea -bone in the center of a semicircular canal

Ceruminous glands are ________. -glands found in the lateral corners of your eye -saliva glands found at the base of the tongue -modified apocrine sweat glands -modified taste buds

Which of the following structures is not part of the external ear? external acoustic meatus pharyngotympanic tube pinna auricle

The structure that allows equalization of the pressure in the middle ear with that outside the body is the external auditory meatus. True False

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

Without functioning cristae ampullares, the semicircular ducts would not function. True False

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

The fluid contained within the membranous labyrinth is called perilymph. True False

What type of channel is responsible for the initial changes in the membrane potential of the hair cells, which ultimately determines the cochlear nerve response to sound? leakage mechanically gated chemically gated voltage-gated

Transduction of lower frequency sound waves occurs at the __________ of the cochlea. proximal end apex middle base

At rest, when no sound is entering the cochlea, the hair cells send no signal. True False

Height of a wave is called the __________. wavelength amplitude pitch frequency

The oval window is connected directly to which passageway? scala vestibuli external acoustic meatus pharyngotympanic tube scala tympani

As sound levels increase in the spiral organ (of Corti), ________. -inner hair cells stiffen the basilar membrane -outer hair cells bend the cilia away from the kinocilium -inner hair cells bend the cilia away from the kinocilium -outer hair cells stiffen the basilar membrane

Receptors for hearing are located in the ________. vestibule cochlea semicircular canals tympanic membrane

Which pairing of terms is incorrectly related? -frequency of sound waves: loudness of the sound -quality of a sound : frequency of the sound -amplitude of a sound: intensity of the sound -frequency of sound waves: number of wavelengths

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

What structure helps us localize sound? the auditory cortex the inferior colliculus the superior olivary nucleus the cochlea

The sensation of loudness or the volume of a sound is detected by ________. -vibration along a greater length of the basilar membrane, stimulating a greater number of hair cells -faster vibration of the basilar membrane resulting in a higher frequency of hair cell stimulation -greater movement of the basilar membrane resulting in greater deflection of the hair cells -high volume sounds can travel all the way the apex of the scala vestibule with enough energy remaining to deflect hair cells

A patient has a loss of hearing in only one ear. Which of the following is likely to be a result? -The patient will not be able to track objects with the eye on the same side as the hearing loss. -The patient will have increased sensitivity to sound in the unaffected ear. -The patient will not be able to localize the origin of sounds. -The patient will have a loss of balance with dizziness and vertigo.

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 ________. -middle ear infection -a perforated tympanic membrane -damage to the hair cells near the oval window in the cochlear duct -an overgrowth of bony tissue, fusing the ossicles together

Which statement about sound localization is not true? -It requires input from both ears. -It requires processing at the cortical level. -It uses time differences between sound reaching the -two ears. -It is difficult to discriminate sound sources in the midline.

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

During otitis media, large amounts of fluid or pus may accumulate in the tympanic cavity; the fluid is primarily ______. interstitial fluid blood bacterial fluid a hypertonic fluid

How are the olfactory receptors activated? -Odorants dissolve in the mucus and bind to receptors. -Olfactory cilia move mucus over the receptors. -Mitral cells relay signals to the olfactory bulbs. -The olfactory tracts transduce signals to the hypothalamus.

Choose the FALSE statement about the olfactory epithelium. -It contains olfactory sensory neurons. -It is made of simple squamous epithelium. -It is located in the roof of the nasal cavity. -It is coated with mucus at the air interface.

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? -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. -The belief that we can smell so many different distinct odors is a psychological process referred to as an uncinate fit or olfactory hallucination. -Taste receptors that are active at the same time influence the subtlety of what we smell. -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.

Olfactory cells and taste buds are normally stimulated by ________. -movement of a cupula -substances in solution -stretching of the receptor cells -the movement of otoliths

Which of the follow types of neurons are replaced throughout adult life? -retinal ganglion cells -olfactory receptor cells -retinal bipolar cells -auditory outer and inner hair cells

Which of the following is not a characteristic of olfactory receptor cells? They are ciliated. They have a short life span of about 60 days. They are chemoreceptors. They are unipolar neurons.

Which of the following would be the LEAST likely to be associated with the development of motion sickness? -driving rapidly over winding roads -reading a book while being a passenger in a car -having a non-functional vestibular apparatus -taking a ride in a Ferris wheel

Which of the following is the basic taste quality responsible for the amino acid flavor of steak? umami sweet bitter sour

Most taste buds are located __________. -on the top surface of the fungiform papillae -on the side of the oral cavity -on the top of the vallate papillae -on the top of the foliate papillae

Which of the following is NOT a requirement for something to be tasted? -The tastant must contact gustatory hairs. -The tastant must contact the basal epithelial cells of the taste buds. -The tastant must dissolve in saliva. -The tastant must diffuse into a taste pore.

Flavor preferences, our likes and dislikes are said to have a "homeostatic value". Which of the following is the best example of this homeostatic value for taste preferences? -Alkaloids are chemical compounds in plants that are frequently toxic "antifeedant" chemicals. Alkaloids are often unpleasantly bitter. -Capsaicin is a chemical compound in chili peppers. Nociceptors in the mouth respond to this chemical with the sensation of heat. -The temperature, smell and texture of foods will influence its overall taste. -Monosodium glutamate is a food additive that stimulates umami taste (gustatory) cells.

Which of the following is true about gustatory receptors? -The receptors generate an action potential in response to chemical stimuli. -In order for a chemical to be sensed, it must be hydrophobic. -All gustatory receptors have the same threshold for activation. -Complete adaptation occurs in about one to five minutes.

aste buds are not found ________. -in fungiform papillae -in filiform papillae -in circumvallate papillae -lining the buccal cavity

Select the correct statement about olfaction. -Some of the sensation of olfaction is actually one of pain. -Substances must be volatile and hydrophobic in order to activate olfactory receptors. -Olfactory receptors have a high degree of specificity toward a single type of chemical. -Olfactory adaptation is only due to fading of receptor cell response.

Which of the following taste sensations is incorrectly matched to the chemicals that produce it? -salty-metal ions -bitter-alkaloids -sour-acids -umami-triglycerides and fatty acids -sweet-organic substances such as sugar and some lead salts

The receptor membranes of gustatory cells are ________. -taste buds -basal cells -gustatory hairs -fungiform papillae

Bitter taste is elicited by ________. metal ions acids hydrogen ions alkaloids

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

Congenital sensorineural deafness most commonly involves damage to ______. the auricles the cochlear hair cells the auditory ossicles All of the listed responses are correct.

Which of the following are the receptors for static equilibrium? otolith membrane hair cells cochlea saccule

What does the vestibular apparatus detect? sound waves joint position head position in space balance

Which of the following correctly matches the equilibrium receptor organs to the type of equilibrium it monitors? saccule/dynamic equilibrium maculae/static equilibrium crista ampullaris/static equilibrium maculae/dynamic equilibrium

Where are equilibrium receptors located? -in the semicircular canals, in the spiral organ of Corti, and in the vestibule of the ear -only in the semicircular canals of the ear -only in the vestibule of the ear -in the semicircular canals and in the vestibule of the ear

The semicircular canals are adapted to detect static equilibrium. True False

Which of the following is true of receptors for dynamic equilibrium? -The receptors for dynamic equilibrium are located in the vestibule of the ear. -The receptors for dynamic equilibrium are not stimulated by head movement. -The receptors for dynamic equilibrium are called maculae. -The receptors for dynamic equilibrium respond to rotational forces.

Information from balance (equilibrium) receptors is processed in __________. the brain stem somatic receptors in the muscles visual receptors the cerebral cortex

Labyrinthitis is a medical condition often caused by 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? ringing in the ears (tinnitus) loss of balance and dizziness loss of hearing auditory hallucination

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? -Reducing the inertia of head spin will reduce the flow of endolymph that deflects the hair cells of the crista ampullaris. -This helps keep the motions detected by the eyes congruent (aligned) with the motions sensed by the vestibular apparatus. -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. -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.

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

Information from balance receptors goes directly to the ________. motor cortex visual cortex brain stem reflex centers back muscles

Motion sickness seems to ________. -respond best to medication that "boosts" vestibular inputs -result from mismatch between visual and vestibular inputs -result from activation of nausea centers in the brain stem -respond best to medication taken after salivation and pallor begins

An essential part of the maculae involved in static equilibrium is (are) the ________. spiral organ (of Corti) scala media cupula otoliths

Select the correct statement about equilibrium. -Cristae respond to angular acceleration and deceleration. -The weight of the endolymph contained within the semicircular canals against the maculae is responsible for static equilibrium. -Hair cells of both types of equilibrium hyperpolarize only, resulting in an increased rate of impulse transmission. -Due to dynamic equilibrium, movement can be perceived if rotation of the body continues at a constant rate.

The receptor for static equilibrium is the ________. cochlear duct utricle semicircular canals macula

Which statement about malnutrition-induced night blindness is most accurate? -Visual pigment content is reduced in cones more than rods. -Vitamin supplements can reverse degenerative changes. -The most common cause is vitamin D deficiency. -The impaired vision is caused by reduced cone function.

Tinnitus, vertigo, and gradual hearing loss typify the disorder called ________. motion sickness strabismus Ménière's syndrome conjunctivitis

Which of the following is not a possible cause of conduction deafness? impacted cerumen otosclerosis cochlear nerve degeneration middle ear infection

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