Chapter 11 Flashcards
(97 cards)
1
Q
blephar/o
A
eyelid
2
Q
-cusis
A
hearing
3
Q
irid/o
A
iris
4
Q
kerat/o
A
horny, hard, cornea
5
Q
myring/o
A
tympanic membrane, eardrum
6
Q
opthalm/o
A
eye vision
7
Q
-opia
A
vision condition
8
Q
opt/o
A
eye vision
9
Q
ot/o
A
ear, hearing
10
Q
phak/o
A
lens of eye
11
Q
presby/o
A
old age
12
Q
retin/o
A
retina, net
13
Q
scler/o
A
sclera, white of eye, hard
14
Q
trop/o
A
turn, change
15
Q
tympan/o
A
tympanic membrane, eardrum
16
Q
adnexa
A
means the accessory
or adjoining anatomical parts of an organ. The term
adnexa is plural
17
Q
adnexa of the eye
A
also known as adnexa oculi, are
the structures outside the eyeball. These include the orbit,
eye muscles, eyelids, eyelashes, conjunctiva, and lacrimal
apparatus
18
Q
binocular vision
A
occurs when the muscles of
both eyes work together in coordination to make normal
depth perception possible. Depth perception is the ability
to see things in three dimensions.
19
Q
canth
A
corner of the eye
20
Q
canthus
A
angle where the upper and lower eye lids meet
21
Q
cilia
A
which are small hairs, make up
the eyebrows and eyelashes. Cilia are also present in
the nose to prevent foreign matter from being inhaled.
22
Q
tarsus
A
also known as the tarsal
plate, is the framework within the upper and lower
eyelids that provides the necessary stiffness and shape
(tars means edge of the eyelid, and -us is a singular
noun ending) (plural, tarsi). Note: Tarsus also refers to
the seven tarsal bones of the foot’s instep.
23
Q
tars
A
edge of eyelid
24
Q
conjuctiva
A
is the transparent
mucous membrane that lines the underside of each eyelid
and continues to form a protective covering over the
exposed surface of the eyeball
25
lacrimal duct
also known as the nasolacrimal
duct, is the passageway that drains excess tears into
the nose.
26
lacrimal canal
consists of a duct at the inner
corner of each eye. These ducts collect tears and
empty them into the lacrimal sacs. Crying is the overflowing
of tears from the lacrimal canals.
27
sclera
also known as the white of the
eye, maintains the shape of the eye and protects the
delicate inner layers of tissue. This tough, fibrous tissue
forms the outer layer of the eye, except for the part
covered by the cornea.Note: The combining formscler/o
means the white of the eye, and it also means hard.
28
choroid
also known as the choroid
coat, is the opaque middle layer of the eyeball that
contains many blood vessels and provides the blood
supply for the entire eye. Opaque means that light
cannot pass through this substance.
29
retina
the sensitive innermost
layer that lines the posterior segment of the eye. The
retina receives nerve impulses and transmits them to
the brain via the optic nerve. This is also known as the
second cranial nerve
30
anterior segment
The anterior chamber is located behind the cornea
and in front of the iris. The posterior chamber is
located behind the iris and in front of the ligaments
holding the lens in place. Note: Don’t confuse the
posterior chamber with the posterior segment
31
aqueous humor
which is also known
as aqueous fluid, fills both of these chambers. The
term aqueous means watery or containing water. As
used here, the term humor describes any clear body
liquid or semifluid substance.
n The aqueous humor helps the eye maintain its
shape and nourishes the intraocular structures. This
fluid is constantly filtered and drained through the
trabecular meshwork and the canal of Schlemm
32
posterior segment
The posterior segment, which makes up the remaining
two-thirds of the eyeball, is lined with the retina and filled
with vitreous (VIT-ree-us) humor. Also known as vitreous
gel, this is a soft, clear, jelly-like mass that contains
millions of fine fibers. These fibers, which are attached to
the surface of the retina, help the eye maintain its shape
33
rods and cones of the retina
of the retina receive images that
have passed through the lens of the eye. These images
are converted into nerve impulses and transmitted to
the brain via the optic nerve. Rods are the black and
white receptors, and cones are the color receptors.
34
macula
also known as the
macula lutea, is the clearly defined light-sensitive area
in the center of the retina that is responsible for sharp
central vision. Note that the term macula means a
small spot. A macula, also known as a macule, can also
refer to a small, discolored spot on the skin, such as a
freckle
35
fovea centralis
is a
pit in the middle of the macula. Color vision is best in
this area because it contains a high concentration of
cones and no rods.
36
optic disk
also known as the blind spot, is a
small region in the eye where the nerve endings of the
retina enter the optic nerve. This is called the blind
spot, because it does not contain any rods or cones to
convert images into nerve impulses.
37
uvea
is the pigmented layer of the eye.
It has a rich blood supply and consists of the choroid,
ciliary body, and iris
38
ciliary body
which is located within
the choroid, is a set of muscles and suspensory ligaments
that adjust the thickness of the lens to refine the focus of
light rays on the retina (Figure 11.6).
n The ciliary body produces the aqueous humor that fills
the anterior segment of the eye.
n To focus on nearby objects, these muscles adjust the
lens to make it thicker.
n To focus on distant objects, these muscles stretch the
lens so it is thinner.
39
iris
the colorful circular structure that surrounds
the pupil (Figure 11.3). The muscles within the iris control
the amount of light that is allowed to enter the eye
through the pupil.
n To decrease the amount of light entering the eye, the
muscles of the iris contract, making the opening of the
pupil smaller.
n To increase the amount of light entering the eye, the
muscles of the iris relax, or dilate, making the opening
of the pupil larger. See dilation under the section on
diagnostic procedures. Note that the term dilate refers
to expanding any opening of the body, for example,
the dilating pores of the skin or of the cervix during
childbirth (see Chapter 14).
40
cornea
is the transparent outer
surface of the eye covering the iris and pupil. It is the
primary structure focusing light rays entering the eye
41
pupil
is the black circular opening in the center of
| the iris that permits light to enter the eye.
42
accomodation
is the process
whereby the eyes make adjustments for seeing
objects at various distances. These adjustments
include contraction (narrowing) and dilation (widening)
of the pupil, movement of the eyes, and changes
in the shape of the lens.
43
convergence
is the simultaneous
inward movement of the eyes toward each other. This
occurs in an effort to maintain single binocular vision
as an object comes nearer.
44
emmetr
in proper measure
45
emmetropia
is the normal
relationship between the refractive power of the eye
and the shape of the eye that enables light rays to
focus correctly on the retina
46
refraction
also refractive power, is the ability of the
| lens to bend light rays so they focus on the retina.
47
visual acuity
is the ability to distinguish
object details and shape at a distance. Acuity
means sharpness
48
ptosis
drooping or sagging
49
chalazion
is a nodule or cyst,
usually on the upper eyelid, caused by obstruction in a
sebaceous gland (plural, chalazia). A chalazion is a
type of granuloma (see Chapter 12). Compare with a
hordeolum
50
trop
turn
51
hordeolum
also known as a stye,
| is a pus-filled and often painful lesion on the eyelid
52
darcy/o
tear
53
conjunctivits
also known as
pinkeye, is an inflammation of the conjunctiva that is
usually caused by an infection or allergy (conjunctiv
means conjunctiva, and -itis means inflammation).
54
anisocoria
is a condition in
| which the pupils are unequal in size
55
cataract
is the loss of transparency of
the lens that causes a progressive loss of visual clarity.
The formation of most cataracts is associated with
aging; however, this condition can be congenital or
due to an injury or disease
56
mydrias
dilation of the pupil
57
papill
nipplelike
58
nystagmus
is an involuntary, constant,
rhythmic movement of the eyeball that can be congenital
or caused by a neurological injury or drug use
59
miosis
is the contraction of the pupil,
normally in response to exposure to light, but also
possibly due to the use of prescription or illegal drugs
60
macular degeneration
is a gradually
progressive condition in which the macula at the center
of the retina is damaged, resulting in the loss of central
vision, but not in total blindness (macul means spot, and
-ar mean pertaining to) (Figure 11.8D).
n Age-related macular degeneration occurs most frequently
in older people and is the leading cause of
legal blindness in those older than age 60.
n Dry macular degeneration, which accounts for 90% of
these cases, is caused by the slow deterioration of the
cells of the macula.
61
glaucoma
is a group of diseases characterized
by increased intraocular pressure that causes
damage to the retinal nerve fibers and the optic nerve
(Figure 11.8C). This increase in pressure is caused by a
blockage in the flow of fluid out of the eye.this pressure can cause the loss of peripheral vision and
eventually blindness.
62
eso
inward
63
dipl
double
64
nycatlopia
night blindness
65
esotropia
cross eyed
66
exotropia
opposite crosseyed
67
hyperopia
farsighted
68
myopia
nearsighted
69
strabismus
eyes point in different directions
70
amblyopia
is a dimness of
vision or the partial loss of sight, especially in one eye,
without detectable disease of the eye (ambly means
dim or dull, and -opia means vision condition).
71
scotoma
also known as blind spot,
is an abnormal area of diminished vision surrounded
by an area of normal vision
72
mileusis
carving
73
pinna
also known as the auricle or the
outer ear, is the external portion of the ear. The pinna
captures sound waves and transmits them into the
external auditory canal.
74
external auditory canal
transmits these sound waves
| to the tympanic membrane (eardrum) of themiddle ear.
75
cerumen
ear waxsecreted by ceruminous glands that line the auditory
canal. This sticky yellow-brown substance has protective
functions because it traps small insects, dust,
debris, and some bacteria to prevent them from
entering the middle ear.
76
middle ear
which is located between the outer ear
and the inner ear, transmits sound across the space
between these two parts
77
tympanic membrane
also known
as the eardrum, is located between the outer and
middle ear (Figure 11.13). The word parts myring/o
and tympan/o both mean tympanic membrane. When
sound waves reach the eardrum, this membrane
transmits the sound by vibrating.
78
mastoid process
is the temporal bone containing
| hollow air space that surrounds the middle ear.
79
auditory ossicles
are three small bones
located within the middle ear (Figure 11.12). The role of
these bones is to transmit the sound waves from the eardrum
to the inner ear by vibration. These bones are named
for the Latin terms that describe their shapes
80
malleus
hammer
81
incus
anvil
82
stapes
stirrup
83
Eustachian tubes
The eustachian tubes (you-STAY-shun), also known as
the auditory tubes, are narrow tubes that lead from the
middle ear to the nasal cavity and the throat. The purpose
of these tubes is to equalize the air pressure
within the middle ear with that of the outside
atmosphere.
84
inner ear
contains the sensory receptors for hearing
and balance. The structures of the inner ear are known as
the labyrinth
85
oval windows
which is located under the base of
the stapes, is the membrane that separates the middle
ear from the inner ear. Vibrations enter the inner ear
through this structure.
86
cochlea
is the snail-shaped
structure of the inner ear and is where sound vibrations
are converted into nerve impulses. Located
within the cochlea are the cochlear duct, the organ
of Corti, the semicircular canals, and the acoustic
nerves. Cochlea comes from the Greek term
for snail.
87
organ of corti
receives the vibrations from the
cochlear duct and relays them to the auditory nerve
fibers. These fibers transmit the sound impulses to theauditory center of the brain’s cerebral cortex, where
they are heard and interpreted.
88
semicircular canals
contain the liquid
endolymph and sensitive hair-like cells. The bending
of these hair-like cells in response to the movements of
the head sets up impulses in nerve fibers to help
maintain equilibrium. Equilibrium is the state of
balance.
89
acoustic nerves
transmit this
information to the brain, and the brain sends messages
to muscles in all parts of the body to ensure that
equilibrium is maintained. These nerves are discussed
90
air conduction
is the process by which sound waves
enter the ear through the pinna and then travel down
the external auditory canal until they strike the tympanic
membrane, which is located between the outer
ear and middle ear.
91
bone conduction
occurs as the eardrum vibrates and
causes the auditory ossicles of the middle ear to
vibrate. The vibration of these bones transmits the
sound waves through the middle ear to the oval window
of the inner ear.
92
sensorinural conduction
occurs when these sound vibrations reach the inner
ear. The structures of the inner ear receive the sound
waves and relay them to the auditory nerve for transmission
to the brain.
93
ankylosis
fused together
94
myc
fungus
95
vertigo
is a sense of whirling, dizziness,
and loss of balance that are often combined with
nausea and vomiting. Although it is a symptom of
many disorders, recurrent vertigo is sometimes associated
with inner ear problems such as Ménière’s
disease.
96
cholesteat
cholesterol
97
tinnitus
also commonly pronounced
(TIN-uh-tus), is a condition of a ringing, buzzing, or
roaring sound in one or both ears. It is often associated
with hearing loss and is more likely to occur when
there has been prolonged exposure to loud noises.
