Chapter 17: Sense Organs: The Eye And The Ear

Front 1

accommodation

Back 1

Normal adjustment of the eye to focus on objects from far to near. The ciliary body adjusts the lens (rounding it) and the pupil constricts. When the eye focuses from near to far, the ciliary body flattens the lens and the pupil dilates.

Front 2

anterior chamber

Back 2

Area behind the cornea and in front of the lens and iris. It contains aqueous humor.

Front 3

aqueous humor

Back 3

Fluid produced by the ciliary body and found in the anterior chamber. A humor is any fluid, including blood and lymph.

Front 4

biconvex

Back 4

Consisting of two surfaces that are rounded, elevated, and curved evenly, like part of a sphere.

The lens of the eye is a biconvex body.

Front 5

choroid

Back 5

Middle, vascular layer of the eye, between the retina and the sclera.

Front 6

ciliary body

Back 6

Structure surrounding the lens that connects the choroid and iris. It contains ciliary muscles, which control the shape of the lens, and it secretes aqueous humor.

Front 7

cone

Back 7

Photoreceptor cell in the retina that transforms light energy into a nerve impulse.

Cones are responsible for color and central vision.

Front 8

conjunctiva

Back 8

Delicate membrane lining the undersurface of the eyelids and covering the anterior eyeball.

Front 9

cornea

Back 9

Fibrous transparent layer of clear tissue that extends over the anterior portion of the eyeball.

Front 10

fovea centralis

Back 10

Tiny pit or depression in the retina that is the region of clearest vision.

Front 11

fundus of the eye

Back 11

Posterior, inner part of the eye.

Front 12

iris

Back 12

Pigmented (colored) layer that opens and closes to allow more or less light into the eye.

The central opening of the iris is the pupil.

Front 13

lens

Back 13

Transparent, biconvex body behind the pupil of the eye.

It bends (refracts) light rays to bring them into focus on the retina.

Front 14

macula

Back 14

Yellowish region on the retina lateral to and slightly below the optic disc; contains the fovea centralis, which is the area of clearest vision.

Front 15

optic chiasm

Back 15

Point at which optic nerve fibers cross in the brain.

Front 16

optic disc

Back 16

Region at the back of the eye where the optic nerve meets the retina. It is the blind spot of the eye because it contains only nerve fibers, no rods or cones, and is thus insensitive to light.

Front 17

optic nerve

Back 17

Cranial nerve carrying impulses from the retina to the brain (cerebral cortex).

Front 18

pupil

Back 18

Central opening of the eye, surrounded by the iris, through which light rays pass. It appears dark.

Front 19

refraction

Back 19

Bending of light rays by the cornea, lens, and fluids of the eye to bring the rays into focus on the retina.

Refract means to break.

Front 20

retina

Back 20

Light-sensitive nerve cell layer of the eye containing photoreceptor cells (rods and cones).

Front 21

rod

Back 21

Photoreceptor cell of the retina essential for vision in dim light and for peripheral vision.

Front 22

sclera

Back 22

Tough, white outer coat of the eyeball.

Front 23

thalamus

Back 23

Relay center of the brain. Optic nerve fibers pass through the thalamus on their way to the cerebral cortex.

Front 24

vitreous humor

Back 24

Soft, jelly-like material behind the lens in the vitreous chamber; helps maintain the shape of the eyeball.

Front 25

aque/o

Back 25

water

Front 26

blephar/o

Back 26

eyelid

Front 27

conjunctiv/o

Back 27

conjunctiva

Front 28

cor/o

Back 28

pupil

Front 29

corne/o

Back 29

cornea

Front 30

cycl/o

Back 30

ciliary body or muscle of the eye.

Front 31

dacry/o

Back 31

tears, tear duct

Front 32

ir/o, irid/o

Back 32

iris (colored portion of the eye around the pupil.

Front 33

kerat/o

Back 33

cornea

Front 34

lacrim/o

Back 34

tears

Front 35

ocul/o

Back 35

eye

Front 36

ophthalm/o

Back 36

eye

Front 37

opt/o, optic/o

Back 37

eye, vision

Front 38

palpebr/o

Back 38

eyelid

Front 39

papill/o

Back 39

optic disc; nipple-like

Front 40

phac/o, phak/o

Back 40

lens of the eye

Front 41

pupill/o

Back 41

pupil

Front 42

retin/o

Back 42

retina

Front 43

scler/o

Back 43

sclera (white of the eye); hard

Front 44

uve/o

Back 44

uvea; vascular layer of the eye (iris, ciliary body, and choroid)

Front 45

vitre/o

Back 45

glassy

Front 46

ambly/o

Back 46

dull, dim

Front 47

dipl/o

Back 47

double

Front 48

glauc/o

Back 48

gray

Front 49

mi/o

Back 49

smaller, less

Front 50

mydr/o

Back 50

widen, enlarge

Front 51

nyct/o

Back 51

night

Front 52

phot/o

Back 52

light

Front 53

presby/o

Back 53

old age

Front 54

scot/o

Back 54

darkness

Front 55

xer/o

Back 55

dry

Front 56

-opia

Back 56

vision

Front 57

-opsia

Back 57

vision

Front 58

-tropia

Back 58

to turn

Front 59

astigmatism

Back 59

Defective curvature of the cornea or lens of the eye.

Front 60

hyperopia
(hypermetropia)

Back 60

Farsightedness

Front 61

myopia

Back 61

Nearsightedness

Front 62

presbyopia

Back 62

Impairment of vision as a result of old age.

Front 63

cataract

Back 63

Clouding of the lens, causing decreased vision.

Front 64

chalazion

Back 64

Small, hard, cystic mass (granuloma) on the eyelid.

Front 65

diabetic retinopathy

Back 65

Retinal effects of diabetes mellitus include micro aneurysms, hemorrhages, dilation of retinal veins, and neovascularization (new blood vessels form in the retina).

Front 66

glaucoma

Back 66

Increased intraocular pressure results in damage to the retina and optic nerve with loss of vision.

Front 67

hordeolum
(stye or sty)

Back 67

Localized purulent, inflammatory staphylococcal infection of a sebaceous gland in the eyelid.

Front 68

macular degeneration

Back 68

Progressive damage to the macula of the retina.

Front 69

nystagmus

Back 69

Repetitive rhythmic movements of one or both eyes.

Front 70

retinal detachment

Back 70

Two layers of the retina separate from each other.

Front 71

strabismus

Back 71

Abnormal deviation of the eye.

Front 72

auditory canal

Back 72

Channel that leads from the pinna to the eardrum.

Front 73

auditory meatus

Back 73

Auditory canal.

Front 74

auditory nerve fibers

Back 74

Carry impulses from the inner ear to the brain (cerebral cortex).

These fibers compose the vestibulocochlear nerve (cranial nerve VIII).

Front 75

auditory tube

Back 75

Channel between the middle ear and the nasopharynx; eustachian tube.

Front 76

auricle

Back 76

Flap of the ear; the protruding part of the external ear, or pinna.

Front 77

cerumen

Back 77

Waxy substance secreted by the external ear; also called ear wax.

Front 78

cochlea

Back 78

Snail-shaped, spirally would tube in the inner ear; contains hearing-sensitive receptor cells.

Front 79

endolymph

Back 79

Fluid within the labyrinth of the inner ear.

Front 80

eustachian tube

Back 80

Auditory tube.

Front 81

incus

Back 81

Second osscile (bone) of the middle ear.

incus means anvil.

Front 82

labyrinth

Back 82

Maze-like series of canals of the inner ear. This includes the cochlea, vestibule, and semicircular canals.

Front 83

malleus

Back 83

First ossicle of the middle ear;

malleus means hammer.

Front 84

organ of Corti

Back 84

Sensitive auditory receptor area found in the cochlea of the inner ear.

Front 85

ossicle

Back 85

Small bone of the ear; includes the malleus, incus, and stapes.

Front 86

oval window

Back 86

Membrane between the middle ear and the inner ear.

Front 87

perilymph

Back 87

Fluid contained in the labyrinth of the inner ear.

Front 88

pinna

Back 88

Auricle; flap of the ear.

Front 89

semicircular canals

Back 89

Passages in the inner ear associated with maintaining equilibrium.

Front 90

stapes

Back 90

Third ossicle of the middle ear.

Stapes means stirrup.

Front 91

tympanic membrane

Back 91

Membrane between the outer and the middle ear; also called the eardrum.

Front 92

vestibule

Back 92

Central cavity of the labyrinth, connecting the semicircular canals and the cochlea.

The vestibule contains two structures, the saccule and utricle, that help to maintain equilibrium.

Front 93

acous/o

Back 93

hearing

Front 94

audi/o

Back 94

hearing; the sense of hearing

Front 95

audit/o

Back 95

hearing

Front 96

aur/o, auricul/o

Back 96

ear

Front 97

cochle/o

Back 97

cochlea

Front 98

mastoid/o

Back 98

mastoid process

Front 99

myring/o

Back 99

eardrum, tympanic membrane

Front 100

ossicul/o

Back 100

ossicle

Front 101

ot/o

Back 101

ear

Front 102

salping/o

Back 102

eustachian tube, auditory tube

Front 103

staped/o

Back 103

stapes (third bone of the middle ear)

Front 104

tympan/o

Back 104

eardrum,
tympanic membrane

Front 105

vestibul/o

Back 105

vestibule

Front 106

-acusis or -cusis

Back 106

hearing

Front 107

-meter

Back 107

instrument to measure

Front 108

-otia

Back 108

ear condition

Front 109

acoustic neuroma

Back 109

Benign tumor arising from the acoustic vestibulocochlear nerve (eighth cranial nerve) in the brain.

Front 110

cholesteatoma

Back 110

Collection of skin cells and cholesterol in a sac within the middle ear.

Front 111

deafness

Back 111

Loss of the ability to hear.

Front 112

Meniere disease

Back 112

Disorder of the labyrinth of the inner ear; elevated endolymph pressure within the cochlea (cochlea hydrops) and semicircular canals (vestibular hydrops).

Front 113

otitis media

Back 113

Inflammation of the middle ear.

Front 114

otosclerosis

Back 114

Hardening of the bony tissue of the middle ear.

Front 115

tinnitus

Back 115

Sensation of noises (ringing, buzzing, whistling, booming) in the ears.

Front 116

vertigo

Back 116

Sensation of irregular or whirling motion either of oneself or of external objects.