Week 6 - Special Senses Flashcards
Which structures lubricate the eyeball?
conjunctiva
Lacrimal apparatus
What are the photoreceptors of the eye called?
rods and cones
If at midnight, you are driving to an unfamiliar street that has no street lights, could you distinguish the color of the individual house?
no
Would you rest tired eyes by looking at objects far away or by looking at near objects?
faraway
Why is vision not possible when light strikes the blind spot?
there are no photoreceptors there
What changes occur when you move from a dark room to a brightly lit room?
pupil constricts
The name of the “white of the eye” is called the
sclera
An abnormal elevation in intraocular pressure may lead to a condition called
glaucoma
Why is the glaucoma serious?
And how is it treated?
- retinal damage may result
- treated by diuretics
List the structures through which light passes in the eye:
- cornea
- aqueous humor
- lens
- vitreous humor
The portion of the eye that is involved in image formation is the
retina
An occlusion in the venous sinus might result in:
glaucoma
The portion of the eyeball that contains aqueous humor is the
anterior cavity
The densest concentration of cones is found in the
fovea centralis
Which of the following statements is INCORRECT?
a. the vascular tunic is composed of the choroid, ciliary body, and cornea
b. the sclero-corneal junction is the location of the venous sinus
c. the aqueous humor is secreted by the ciliary body
d. the retina includes the optic disc, entry and exit of nerves and blood vessels on the nasal (medial) side of the macula lutea
a. the vascular tunic is composed of the choroid, ciliary body, and cornea
A person who experienced severe brain damage to the left half of the brain would be expected to lose vision in
the lateral portion of the left eye and the medial portion of the right
Via the process known as accomodation, when one views a distant object, the eye:
- relaxes the ciliary muscles
- Allows the lens to flatten
Aqueous humor is
- important in light refraction within the eye, 2. often found in excess in patients with glaucoma
Without his glasses, Bill’s visual acuity is 20/100. This means that:
at 20 feet, he sees what most people see at 100 feet.
When a person is nearsighted, what kind of lens can correct their vision?
Concave lens
(curving inward)
Which statement is true about the choroid?
a. it is the vascular layer of the eye
b. in its absence, visual acuity is appreciably reduced
c. it contains a dark pigment which absorbs stray light
d. a portion of it is modified to assist lens accomodation
e. all of the above are correct
e. all of the above are correct
When you look at nearby object, your pupils constrict.
What is the reason for this?
It sharpens the image by using the most curved portion of the lens
The fovea is
the center of sharpest vision
When the eyes accommodate to focus on a nearby object,
the ciliary muscles _____
and the ligaments around the lens ______
ciliary muscles contract
ligaments around the lens relax
Which of the following correctly compares rods and cones?
a. rods are more numerous
b. cones detect movement better
c. cones work best in dim light
d. all of the above
e. none of the above
a. rods are more numerous
Hair cells, endolymph, and the tectorial are all parts of the —
cochlea
The fluid-filled portions of the auditory apparatus include
the inner ear
Destruction of the auditory portion of the left temporal lobe would
reduce most left side hearing and cause a slight right side reduction
Ear infections are most likely to be located in the
middle ear
The stationary membrane in the inner ear is called the
tectorial membrane
Pitch discrimination is possible because different sounds stimulate —
stimulate different regions of the organ of Corti
Which of the following is involved in detecting the changes in movement that occur when you are riding on a rollercoaster?
a. utricle
b. ampulla
c. otoliths
d. saccule
e. all of the above
e. all of the above
Which middle ear bone connects to the oval window?
the stapes
What physiological function does the pinna play?
It focuses and directs sounds into the auditory canal
During a Rinne’s test, the patient was discovered to be unable to hear the tuning fork when held agains the skull. Why?
The patient has sensory deafness
A patient with an ear full of impacted earwax could possibly be suffering from
a form of conductive deafness
