Biology chapter 16 Biol 227 BSU
The optic disc is associated with ______.
Cranial nerve II (the optic nerve)
What chamber is between the iris and cornea?
anterior chamber
What type of fluid is found in the anterior cavity of the eyeball?
aqueous humor
The most visible part of the external ear is called the ______ or ______
auricle pinna
When the ___ membrane moves, the ___ on the spiral organ hair cells distort because they are anchored by the tectorial membrane.
basilar, stereocilia
The process is called the bleaching reaction because rhodopsin goes from a ______ color to ______.
bluish-purple; colorless
Receptors initiate sensory input to the ______.
central nervous system
Earwax is a combination of dead skin cells and ______.
cerumen
What substance, produced in the external ear, impedes microorganism growth?
cerumen
Gustatory cells are ______.
chemoreceptors
What type of receptor is found in the mucous membranes?
exteroceptors
The outmost layer of the eye is called the ______ tunic.
fibrous
The lens is ______ when we are viewing faraway objects.
flattened
Pain is an example of a ______ sense.
general
When the photoreceptors stop _____ the bipolar cells, the bipolar cells can then release their neurotransmitter that binds to receptors on the ganglion cells
inhibiting or blocking
The segment of each photoreceptor that contains organelles for the cell such as mitochondria is the ____ segment.
inner
The segment of the photoreceptors that connects directly to the cell body is the ____ segment.
inner
The retina is the ______ layer of the eye wall.
internal
Specific types of receptors called _____ detect stimuli in the internal organs.
interoceptors
What type of receptor is found in the smooth muscle of organs?
interoceptors
What structure is the dividing line between the anterior and posterior chambers?
iris
Optic tracts extend to which structures after they leave the optic chiasm?
lateral geniculate nucleus of the thalamus, and the superior colliculi
Tactile receptors are a type of ______.
mechanoreceptors
What type of receptor can undergo adaptation?
phasic
If stimulated over a period of time, _____ receptors lose eventually sensitivity.
phasic or adapting
The dissociation of _____ into its two components is called the bleaching reaction.
rhodopsin
The middle and inner ear are in which bone?
temporal bone
The cornea is ______.
transparent
The vascular tunic of the eye is also called the ______.
uvea
Which layer of the eye contains the blood and lymph vessels?
vascular tunic
In the eye, the _____ humor is gelatinous.
vitreous
Which are true of rods?
- There are more than 100 million rod cells per eye - They function well in dim light
Which events occur during bright light adaptation?
- cones gradually adjust - rods become inactive - pupils constrict
Hearing and equilibrium are transmitted along which cranial nerve?
Vestibulocochlear ( VIII)
Hearing and our sense of balance comes from the stimulation of which cranial nerve?
Vestibulocochlear (CN VIII)
The tympanic cavity is filled with ______.
air
Receptors of the human body convert stimulus energy into ______.
an electrical signal
The semicircular ducts are involved in detecting ____ acceleration.
angular or rotational
Receptors in blood vessels that monitor the concentration of carbon dioxide in our blood are called ______.
chemoreceptors
Otitis media is more common in ______.
children
What is the largest structure of the vascular tunic?
choroid
Which structure of the eye absorbs light to prevent it from scattering within the eye?
choroid
The iris is continuous with the ______.
ciliary body
Prior to being stimulated by light, the retinal portion of rhodopsin is in a bent twisted shape called ____ retinal.
cis
The auditory tube is normally _____
closed
The auditory sensory axons of the _____ branch of cranial nerve number ____ terminate in the cochlear nucleus within the brainstem.
cochlear; VIII
What type of photoreceptors detects color?
cones
As we adjust to low light, our ______ becomes nonfunctional and it may take ______ for rhodopsin to become regenerated sufficiently so that you can see well in low-light conditions.
cones; 20-30 minutes
The sphincter pupillae ______ the pupil.
constricts
The limbus is the junction between the sclera and the ______.
cornea
When you go from a bright light environment to a dark environment, you have a slow sensitivity to low light levels. This is called
dark adaptation
Light rays are refracted or bent when they pass through two media of different ______.
densities
Which is an accessory structure of the eye?
eyebrow
When the bipolar cells release their neurotransmitter, the _____ cells propagate a nerve signal along the _____ nerve.
ganglion, optic
The term equilibrium refers to our awareness and monitoring of our ____ position.
head
Optic tracts ultimately are directed to the primary visual cortex in the ______ lobe.
occipital
We use the sense of ____ to sample our environment for information about the food we will eat, the presence of other individuals in the room, or potential danger.
olfaction or smell
The fat surrounding the eye is called ____ fat.
orbital
The segment of each photoreceptor that is composed of hundreds of discs containing photopigments that are capable of absorbing light energy is the _____ segment.
outer
The eyelids are also called
palpebrae
The sphincter pupillae is controlled by the ______ division of the nervous system
parasympathetic
The external ear is located mostly on the outside of the body, while the middle and inner ear areas are housed within the ____ part of the temporal bone.
petrous
In phototransduction, the ____ responds to light stimulation by changing its resting membrane potential, resulting in a change in the neurotransmitter it releases.
photoreceptor
The process by which photoreceptors become activated when the photopigments are altered by light entering the eye is ______.
phototransduction
Each type of photoreceptor has both an outer segment that extends into the ____ layer of the retina and an inner segment.
pigmented
Aqueous humor is secreted into the ____ chamber before traveling to the ____ chamber of the eye.
posterior-anterior
The iris controls the size of the _____
pupil
The area that a receptor cell gathers information from is called the ______.
receptive field
______ occurs when impulses from an organ are perceived as originating from the skin.
referred pain
The apparent distortion of the spoon in the water glass is due to the phenomenon called _____
refraction
The lens is ______ when we are viewing close-up objects.
rounded
The vestibule contains two structures, the utricle and ______
saccule
Sensory receptors in which structures help monitor and adjust our equilibrium?
saccule, utricle, and semicircular ducts
Which part of the eye is an attachment site for extrinsic eye muscles?
sclera
Tarsal glands are ______.
sebaceous glands
When a figure skater does a lengthy spin on the ice, it is the sensory receptors in her ____ canals of the inner ear that are informing her brain about the position of her moving head.
semicircular
Which structures are part of the vestibular complex?
semicircular ducts, utricle, saccule
Receptors for general senses are usually ______.
simple structure
Localization and sensitivity are easily determined in a ______ receptive field.
small
What is the most numerous type of receptor?
tactile receptors
Upon exposure to light, the retinal straightens out and reconfigures into a form called ____ retinal
trans
The external acoustic meatus terminates at the ____ membrane, which is most commonly called the eardrum
tympanic
The external acoustic meatus extends from the auricle to the ______.
tympanic membrane