Chapter 15 special senses
Considering the wavelengths of light received and abundance of various photoreceptors, which color is best received by the retina?
yellow
The structure that supports the organ of Corti is the
basilar membrane.
The vibrations received by the tympanic membrane are transferred to the oval window by the
auditory ossicles.
The external acoustic meatus includes all of the following except the
auditory tube.
The sensory neurons within the olfactory organ are stimulated by ________ in the air.
chemicals
What structure changes the shape of the lens for far and near vision?
ciliary body
Identify the structure labeled "9."
ciliary zonule
The largest numbers of taste buds in adults are associated with the
circumvallate papillae.
The cornea is part of the
fibrous layer.
Gustatory receptors are found in the taste buds of all the following papillae except
filiform.
All of the following is a function of tears except
maintains acidic environment.
Name the three tiny bones located in the middle ear, from lateral to medial.
malleus, incus, and stapes
The hair cells of the utricle and saccule are clustered in
maculae.
Each gustatory cell extends ________ (or taste hairs) into the surrounding fluids through a narrow taste pore.
microvilli
The function of gustatory receptors parallels that of
olfactory receptors.
The middle ear communicates with the nasopharynx through the
pharyngotympanic tube
A ________ is a basic unit or packet of light energy.
photon
An elongate outer layer containing membranous discs and a narrow connecting stalk that attaches the outer segment to the middle layer describes a(n)
photoreceptor
The visual receptors of the retina are called
photoreceptors.
The space between the iris and ciliary body and the lens is the
posterior chamber.
All of the following are true of the lacrimal glands except that they
produce a strongly hypertonic fluid.
The palpebrae do not
produce tears
All of the following are true of the fibrous layer of the eye except that it
produces aqueous humor.
The opening in the iris through which light passes is the
pupil
Identify the three types of cones.
red, green and blue cones
There are three different types of cones, each one sensitive to different light energies. These cones are designated
red, green, and blue.
When light encounters a medium of different density, it is bent or
refracted.
Identify the structure labeled "12."
retina
A pigment synthesized from vitamin A is
retinal
Visual pigments are derivatives of the compound
rhodopsin
In the retina, the correct sequence of neural wiring is
rod - bipolar cell - ganglion cell - thalamus.
Gravity and linear acceleration are sensed in the
saccule and utricle.
________ are photoreceptors that convey our ability to see color.
Cones
Identify the structures labeled "8."
auditory ossicles
In the human eye, most refraction occurs when light passes through the
cornea.
The transparent portion of the fibrous layer is the
cornea.
A typical gustatory cell survives for only about ________ days before it is replaced.
10
Which structure contains the receptors for hearing?
11
________, or pinkeye, results from damage to or irritation of the conjunctival surface.
Conjunctivitis
Axons leaving the olfactory epithelium collect into ________ or more bundles that penetrate the cribriform plate of the ethmoid.
20
Identify the structure that is covered up by the stapes.
4
The olfactory receptor cell can be activated by as few as ________ odorant molecules.
4
An adult has approximately ________ taste buds, each of which contains ________ different receptor cells.
5,000; 40-100
Which structure is known as the vestibule?
6
The visible spectrum for humans extends between a wavelength of 400 nm and ________ nm.
700
What is a generator potential? (Module 15.1B)
A generator potential is the depolarization of sensory neurons capable of generating an action potential.
All of the following occur when a rod is stimulated by light, except
ATP is hydrolyzed.
Taste receptors are distributed in which of the following places?
All of the answers are correct.
All of the following are true regarding the retina except
All of the information from the retina goes directly to the occipital cortex.
________ cells connect photoreceptors to ganglion cells.
Bipolar
________ glands produce a secretion commonly called earwax.
Ceruminous
Define decibel. (Module 15.20A)
Decibels are units of the intensity of sound.
How could a diet deficient in vitamin A affect vision?
Deficiency in vitamin A reduces the amount of retinal that the body could produce, thereby interfering with night vision.
Why does the near point of vision typically increase with age?
Elasticity of the lens decreases with age.
________ fills the membranous labyrinth.
Endolymph
Describe filiform papillae. (Module 15.3B)
Filiform papillae are epithelial projections that are slender and conical. They provide friction for the tongue to move objects in the mouth, but they do not contain taste buds.
Define focal point.
Focal point is the point at which the light rays from an object intersect on the retina.
Define gustation.
Gustation is the sense of taste.
What are gustducins? (Module 15.4A)
Gustducins are G protein complexes that use second messengers to produce the depolarization in the cell from sweet, bitter, and umami sensations.
Define emmetropia.
It is the term for normal vision.
How would a molecule that mimics cAMP not affect an olfactory receptor?
It would decrease sodium permeability.
Describe olfaction.
Olfaction is the sense of smell.
________ glands are modified sebaceous glands located along the margin of the eyelid that secrete a lipid-rich product.
Tarsal
Compare olfactory receptors with receptors for the other special senses. (Module 15.1C)
Olfactory receptors are the dendrites of specialized excitable olfactory neurons, whereas the receptors for the other special senses are receptor cells with inexcitable membranes and form synapses with the processes of sensory neurons.
Define optic radiation.
Optic radiation refers to bundles of projection fibers linking the lateral geniculate bodies of the thalamus with the visual cortex in each cerebral hemisphere.
Name the fluids found within the scala vestibuli, scala tympani, and cochlear duct.
Perilymph fills the scala vestibuli and the scala tympani. Endolymph fills the cochlear duct.
Why do things look blurry underwater without dive goggles or a mask?
Rather than air, light is moving from water into the cornea and is thus refracted too little for a sharp focus.
________ are photoreceptor cells that are most useful in dim light.
Rods
Compare rods with cones.
Rods are active in dim light, and objects appear black and white. Cones require intense light, and objects appear in color.
Cite the functions of sensory receptors in the saccule and utricle. (Module 15.18B)
Sensory receptors in the saccule and utricle are sensitive to changes in horizontal movement and vertical movement, respectively.
Where do the special senses originate? (Module 15.1A)
Special senses originate at the sensory receptor.
Identify the structures of the bony labyrinth.
The bony labyrinth contains the semicircular canals, vestibule, and cochlea.
Which of the following statements concerning vision is false?
The entire retina receives equal representation in the visual cortex.
How do the semicircular canals and the semicircular ducts differ? (Module 15.17B)
The semicircular canals are part of the bony labyrinth, and the canals surround the semicircular ducts, which are part of the membranous labyrinth.
Define otoliths. (Module 15.18A)
They are densely packed calcium carbonate crystals that sit upon the gelatinous otolithic membrane in the maculae.
When the basilar membrane moves, what happens to the hair cells of the spiral organ?
They press against the tectorial membrane.
A patient who experienced head trauma has lost the ability to taste spicy food. You should expect damage to cranial nerve
V.
Taste buds are monitored by cranial nerves
VII, IX, and X.
The human lens focuses light on the photoreceptor cells by
When light encounters a medium of different density, it is bent or A) reflected. B) refracted. C) absorbed. D) transduced. E) propagated.
In which of the following cases would the focal distance be greater? A) a round lens B) a flat lens C) It doesn't matter, focus distance doesn't change with the shape of the lens.
a flat lens
The first step in the process of photoreception is
absorption of a photon by a visual pigment.
Which of the following is not true about rhodopsin?
activates transducin
Visual pigments undergo which three changes during photoreception?
activation, bleaching, and reassembly
The ciliary muscle contracts to
adjust the shape of the lens for close vision.
The sensory receptors of the semicircular canals are located in the
ampullae.
In which of the following cases would the focal distance be greater? A) an object 10 inches away from your nose B) an object 20 feet away C) It doesn't matter, focal distance doesn't change with how far away an object is.
an object 10 inches away from your nose
Identify the space labeled "1."
anterior chamber
The space between the cornea and the iris is the
anterior chamber
Which of the following descriptions best matches the term stereocilia?
bending these produces receptor potential in hair cells
What are the two configurations of retinal?
bent 11-cis form and the linear 11-trans form
Before an olfactory receptor can detect an odorant, it has to
bind to receptors in olfactory dendrites.
Which taste receptors offer a survival advantage when tasting something for the first time? (Module 15.3C)
bitter and sour receptors
The neural layer contains all of the following except
blood vessels.
The ________ is a region of dense bone that surrounds and protects the membranous labyrinth.
bony labyrinth
The abnormality that develops when a lens loses its transparency is known as
cataracts.
Olfactory information is first received by which part of the brain?
cerebrum
Olfactory glands
coat the olfactory epithelium with a pigmented mucus.
Where is the spiral organ located?
cochlea of the internal ear
Interference with the transfer of vibrations from the tympanic membrane to the oval window is ________ deafness.
conductive
The ________ covers most of the exposed surface of the eye.
conjunctiva
Which layer of the eye would be the first affected by inadequate tear production?
conjunctiva
Which of the following descriptions best matches the term aqueous humor
constantly produced and recycled
Pupillary muscle groups are controlled by the ANS. Parasympathetic activation causes pupillary ________, and sympathetic activation causes ________.
constriction; dilation
Which of the following is not true of the vascular layer of the eye?
contains photoreceptors
A sudden rise of room brightness would cause
contraction of the pupillary constrictor muscles.
Which type of lens would correct hyperopia?
converging lens (with at least one convex surface)
When during photoreception is ATP required? (Module 15.12C)
conversion of 11-trans retinal back to 11-cis retinal
Identify the structure labeled "7."
cornea
Which eye structure does not contain blood vessels?
cornea
A ray of light entering the eye will encounter these structures in which order?
cornea - aqueous humor - lens - vitreous body - retina - choroid
Olfactory organs are located in the nasal cavity inferior to the perforated bony structure known as the
cribriform plate.
The elevated ridges within the ampullae of the semicircular canals that support the hair cells are known as a
crista ampullaris.
Which cells develop into the photoreceptors?
ependymal cells of the outer layer of the optic cup
The formal term for the sense of gravity, rotation, and linear acceleration is the sense of
equilibrium.
Sound travels directly to the eardrum through the
external auditory canal.
Identify the cranial nerves that carry gustatory information. (Module 15.4B)
facial, glossopharyngeal, and vagus nerves
A person suffering from ________ can see distant objects more clearly than those that are close.
hyperopia
Identify the structure labeled "14."
fovea centralis
Light passing through the eye along the visual axis strikes what part of the retina?
fovea centralis
An area of the retina that contains only cones and is the site of sharpest vision is the
fovea centralis.
What kind of stimuli can the internal ear sense?
gravity and acceleration, rotation, or sound
The sense of taste is also known as
gustation.
All of the following compose the epithelial projections found on the tongue except
gustatory papillae.
The membrane proteins that respond to chemical stimuli to produce sweet, bitter, and umami sensations are called
gustducins.
The vitreous body
helps to stabilize the eye and give physical support to the retina.
The frequency of a perceived sound depends on
hich part of the cochlear duct is stimulated.
A sound with a frequency of 12,000 hertz would be
high-pitched.
The palpebrae are connected at the
lateral and medial angles of the eye.
Where in the eye is aqueous humor located?
in the anterior cavity, between the cornea and the lens
Which structures develop into the retina? (Module 15.5B)
inner and outer layers of the optic cup
The senses of equilibrium and hearing are provided by receptors of the
internal ear.
The part of the eye that determines eye color is the
iris.
The quantity of neurotransmitter that is released by a hair cell corresponds to all of the following except
is greatest when the hair cell is at a neutral position
A structure that is located at the medial angle of the eye and contains glands that contribute to a gritty deposit is the
lacrimal caruncle.
Which of the following descriptions best matches the term basilar membrane?
moves up and down when the stapes moves back and forth
A person suffering from ________ can see objects that are close, but distant objects appear blurred.
myopia
The olfactory receptors are highly modified
neurons
Some neural tissues retain stem cells and thus the capacity to divide and replace lost neurons. Which of these special senses can replace its damaged neural receptors?
olfaction
Olfactory receptors send axons through the cribriform plate. They synapse on neurons in the
olfactory bulb.
The olfactory organ consists of the ________ and the lamina propria.
olfactory epithelium
Which of the following is not a component of the lamina propria of the olfactory organ?
olfactory epithelium
Gustatory receptors are not located
on the inferior surface of the tongue.
What is the eye's blind spot?
optic disc
What are the first structures that form during eye development? (Module 15.5A)
optic vesicles
The hair cells of the cochlear duct are located in the
organ of Corti.
Name the three layers of the eye.
outer fibrous layer, middle vascular layer, deep inner layer
The ________ ear collects sounds waves and transmits them to the ________ ear, which contains auditory ossicles.
outer; middle
The gap that separates the free margins of the upper and lower eyelids is the
palpebral fissure.
Which of the following is not one of the six primary taste sensations?
peppery
Stimulation of nociceptive receptors within the trigeminal nerve might produce a perception of
peppery hot.
Which of the following descriptions best matches the term stapes?
seals the oval window
When you spin quickly, you may feel dizzy. Which component of the inner ear generates the sensations that can lead to this feeling?
semicircular canal
The vestibular nuclei at the boundary of the pons and the medulla function in all of the following except that they
send information to the vestibular complex of the inner ear.
Movement of the endolymph in the semicircular canals
signals rotational movements
When the ciliary muscles are relaxed, are you viewing something close up or something in the distance?
something in the distance
The cell bodies of sensory neurons that innervate the hair cells of the cochlea form the ________ ganglion.
spiral
Which of the following produces a lipid-rich secretion that prevents the upper and lower eyelids from sticking together at their edges?
tarsal gland
The structure that overlies the organ of Corti is the
tectorial membrane.
What gives eyes their characteristic color?
the density and distribution of melanocytes in the iris
All of the following descriptions applies/apply to the term myopia except
the eyeball is too shallow.
Perception of gravity and linear acceleration depends on
the force exerted by otoliths on hair cells of the maculae in the utricle or saccule.
When all three cone populations are stimulated equally, we perceive
white
A loud noise does not cause
the generation of a wave with a high frequency.
What happens to the pupils when light intensity decreases?
the pupils dilate to let in more light
When an external force bends the stereocilia of the inner ear hair cells,
there is a change in the transmembrane potential
All of the following are true of olfactory pathways except
they project first to the mammillary bodies and then to the thalamus.
Which of the following descriptions best matches the term otoliths?
tiny weights necessary for the static sense of equilibrium
What is the function of the auditory tube?
to allow pressure equalization on both sides of the tympanic membrane
Which of the following descriptions best matches the term ossicles?
transmit movement of the tympanic membrane to the inner ear
Identify the structure labeled "3."
tympanic membrane
Sound waves are converted into mechanical movements by the
tympanic membrane
The auditory ossicles connect the
tympanic membrane to the oval window.
The external ear ends at the
tympanic membrane.
Which of the following anatomical sequences is correct?
tympanum - malleus - incus - stapes - oval window - round window
The taste sensation that is triggered by the amino acids and small peptides is known as
umami.
The ________ convey(s) information about head position with respect to gravity.
utricle and saccule
An abnormal illusion of movement is called
vertigo.
Where are visual images perceived?
visual cortex of the occipital lobe
The gelatinous material found in the posterior cavity is the
vitreous humor.