Ch. 17

Olfactory information is first received by which part of the brain?
The first step in the process of olfaction is __________.
an odorant molecule binding to a specific protein
The olfactory receptors are highly modified ________.
Olfactory receptors send axons through the cribriform plate. They synapse on neurons in the
olfactory bulb.
A normal, relaxed inhalation carries about ________ of the inhaled air to the olfactory organs.
Olfactory organs are located in the nasal cavity inferior to the perforated bony structure known as the ________.
cribriform plate
The olfactory epithelium is sensitive to more than ________ different "primary smells."
Taste buds are monitored by which cranial nerve(s)?
only glossopharyngeal nerve (IX) and facial nerve (VII)
The sense of taste is also known as ________.
The function of gustatory receptors parallels that of
olfactory receptors.
The taste sensation that is triggered by the amino acid glutamate is known as
Taste buds are monitored by cranial nerves
Which of the following is not one of the six primary taste sensations?
peppery (NOT)
Taste receptors are distributed in which of the following places?
portions of the pharynx
portions of the larynx
surface of the tongue
all of the above
Gustatory receptors are located
on the surface of the tongue.
The largest numbers of taste buds in adults are associated with the
circumvallate papillae.
A patient who experienced head trauma has lost the ability to taste spicy food. You should expect damage to cranial nerve ________.
Which of these is the correct pathway for transmission of visual information?
photoreceptor → bipolar cell → bipolar cell
The vitreous body
helps to stabilize the eye and give physical support to the retina.
The human lens focuses light on the photoreceptor cells by
changing shape.
Which of the following produces a lipid-rich secretion that prevents the upper and lower eyelids from sticking together at their edges?
tarsal gland
A ray of light entering the eye will encounter these structures in which order?
conjunctiva → cornea → aqueous humor → lens → vitreous body → retina → choroid
The ________ covers most of the exposed surface of the eye.
The space between the cornea and the iris is the
anterior cavity.
The ciliary muscle contracts to
adjust the shape of the lens for near vision.
The cornea is part of the
both fibrous tunic and neural tunic.
What structure changes the shape of the lens for far and near vision?
ciliary body
The "white" of the eye is part of the __________ tunic.
The gelatinous material that gives the eyeball its basic shape is the
vitreous humor.
The opening in the iris through which light passes is the
The transparent portion of the fibrous tunic is the
The part of the eye that determines eye color is the
Lacrimal glands ____________.
produce lysozyme
produce a watery secretion
moisten the cornea
Lacrimal glands perform all of these functions
All of the following are true of the lacrimal glands, except that they
produce a strongly hypertonic fluid.(NOT)
produce most of the volume of tears.
produce watery, slightly alkaline secretions.
produce lysozyme.
are located in recesses in the frontal bones
In the human eye, most refraction occurs when light passes through the
A sty ________
is often caused by bacteria.
may involve a tarsal gland.
is a painful swelling in an eyelash.
may involve a sebaceous gland.
all of the above
Which of the following is a function of tears?
nourish the cornea and conjunctiva
lubricate the eye
provide oxygen
wash away debris
all of the above
If your vision is 20/15, this means that you can
see objects at 20 feet that individuals with normal eyesight can see at 15 feet.
A sudden rise of room brightness would cause
contraction of the sphincter pupillary muscles.
Why do things look blurry underwater without dive goggles or mask?
Rather than air, light is moving from water into the cornea and is thus refracted too little for a sharp focus.
Which of the following descriptions applies/apply to the term myopia?
nearsightedness, corrected with diverging lens, and image focused in front of retina
________ glands are modified sebaceous glands located along the margin of the eyelid that secrete a lipid-rich product.
A(n) ________ is an infection in one of the glands on the eyelids.
The abnormality that develops when a lens loses its transparency is known as a ________.
Which of the following statements about the retina is TRUE?
Axons carrying its output synapse in the thalamus.
It has photoreceptors that do not respond to dim light.
Ganglion cells send axons to the brain as cranial nerve II.
It has photoreceptors that do not respond to red light.
All of the above are true.
An elongate outer segment containing membranous discs and a narrow connecting stalk that attaches the outer segment to the inner segment describes
a photoreceptor
When all three cone populations are stimulated equally, we perceive
There are three different types of cones, each one sensitive to different light energies. These cones are designated
red, green, blue.
A pigment synthesized from vitamin A is
Which of the following statements concerning vision is false?
The entire retina receives equal representation in the visual cortex. (FALSE)
The visual cortex of the brain receives the entire field of vision.
Approximately half of the fibers in each optic nerve cross to opposite sides of the brain at the optic chiasm.
The image that is formed on the retina is inverted.
Fibers of the optic nerve synapse at the lateral geniculates of the thalamus
Which of the following is true about rhodopsin?
called visual purple
is bleached during photoreception
is the visual pigment in rods
consists of opsin + retinal
all of the above
When a rod is stimulated by light,
the plasma membrane becomes hyperpolarized.
the retinal changes from the 11-cis to the 11-trans form.
less neurotransmitter is released.
cGMP decreases and sodium channels close.
all of the above
The visible spectrum for humans extends between a wavelength of 400 nm and ________ nm.
A(n) ________ is a basic unit or packet of light energy.
The visual receptors of the retina are called ________.
________ are photoreceptors that convey our ability to see color.
People unable to distinguish certain colors have a form of ________.
color blindness
The external acoustic meatus ends at
the tympanic membrane, the eardrum, or the tympanum.
Which of these anatomical sequences is correct?
tympanum-malleus-incus-stapes-oval window-round window
The external ear ends at the
tympanic membrane.
The middle ear communicates with the nasopharynx through the
auditory tube.
The senses of equilibrium and hearing are provided by receptors of the
inner ear
Movement of the endolymph in the semicircular canals
signals rotational movements.
When an external force bends the stereocilia of the inner ear hair cells,
there is a change in the transmembrane potential of the hair cells.
The ________ conveys information about head position with respect to gravity.
both utricle and saccule
A sound with a frequency of 12,000 hertz would
be high-pitched.
A loud noise causes
reflex contractions of middle ear muscles.
an alerting reaction leading to sympathetic activation.
a big pressure pulse entering the cochlear duct at that oval window.
a large movement of the tympanic membrane.
all of the above
Sound travels to the eardrum through the ________.
external auditory canal