Ch 16 Anat Physio
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
Using the image of the eye, match the letter and structure.
A matches Choice eyelashes B matches Choice lacrimal caruncle C matches Choice medial palpebral commissure D matches Choice eyeball
Correctly match the letter to the photoreceptor or eye part.
A Choice choroid B matches Choice pigmented cell layer C matches Choice outer segment D matches Choice inner segment
Optic tracts ultimately are directed to the primary visual cortex in the ______ lobe.
Occipital
______ occurs when impulses from an organ are perceived as originating from the skin.
Referred pain
Hearing and equilibrium are transmitted along which cranial nerve?
VIII
Which cavity of the eyeball is divided into an anterior and posterior chamber?
anterior cavity
What chamber is between the iris and cornea?
anterior chamber
When the membrane moves, the on the spiral organ hair cells distort because they are anchored by the tectorial membrane.
basilar stereocilia
Receptors initiate sensory input to the
central nervous system
Gustatory cells are ______.
chemoreceptors
What is the largest structure of the vascular tunic?
choroid
What structure is filled with pigment from melanocytes?
choroid
The iris is continuous with the ______.
ciliary body
The auditory sensory axons of the branch of cranial nerve number terminate in the cochlear nucleus within the brainstem.
cochlear VIII or 8
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 optic disc is associated with ______.
cranial nerve II
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
The external layer of the eyeball is the ______ tunic.
fibrous
The outmost layer of the eye is called the ______ tunic.
fibrous
Pain is an example of a ______ sense.
general
The term equilibrium refers to our awareness and monitoring of our position.
head
The vestibulocochlear nerve transmits ______ information.
hearing and equilibrium
Where are photoreceptors located?
in the neural layer of the retina
The retina is the ______ layer of the eye wall.
internal
Place the structures of the vascular tunic in order from anterior to posterior
iris, ciliary body, choroid
The process by which your eyes adjust from low light to bright light conditions is
light adaptation
The sense of smell is called ______.
olfaction
A lack of photoreceptors in this structure creates the "blind spot"?
optic disc
The fat surrounding the eye is called
orbital fat
Olfactory receptors ______.
perceive odors
If stimulated over a period of time, receptors lose eventually sensitivity.
phasic
What type of receptor can undergo adaptation?
phasic
The iris controls the size of the ______.
pupil
Most of the eye is ______ the orbit of the skull.
receded into
The area that a receptor cell gathers information from is called the
receptive field
Some individuals experience pain in their left shoulder during a heart attack. This is an example of ______.
referred pain
What structure is the "white" of the eye?
sclera
Sensory receptors in which structures help monitor and adjust our equilibrium?
semicircular ducts utricle saccule
Receptors for general senses are usually ______.
simple in structure
Localization and sensitivity are easily determined in a ______ receptive field.
small
Olfaction is the sense of ______.
smell
Taste buds are found on the tongue and ______.
soft palate
What is the most numerous type of receptor?
tactile receptors
A feature common to all receptors is ______.
the ability to respond to a stimulus
Optic tracts extend to which structures after they leave the optic chiasm?
the lateral geniculate nucleus of the thalamus superior colliculi
The cornea is ______.
transparent
Which are the characteristics of the cornea?
transparent and avascular
Which layer of the eye contains the blood and lymph vessels?
vascular tunic
The apparent distortion of the spoon in the water glass is due to the phenomenon called
refraction
What structure makes up the posterior 5/6 of the fibrous tunic?
sclera
Which part of the eye is an attachment site for extrinsic eye muscles?
sclera
Mechanoreceptors located in the skin and mucous membranes are called ______ receptors.
tactile
Gustation is the sense of
taste
What is the name of structure A in the picture of the spiral organ?
tectorial membrane
The middle and inner ear are in which bone?
temporal bone
What region of the eye contains the ciliary body?
B
