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Accommodation

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.

1

Anterior chamber

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

2

Aqueous humor

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

3

Biconvex

Consisting of two surfaces that are rounded, elevated, and curves evenly, like part of a sphere. The lens of the eye is a biconvex body.

4

Choroid

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

5

Cilira body

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.

6

Cone

Photoreceptor cell in the retina that transforms light energy into a nerve impulse. Cones are responsible for color and central vision.

7

Conjunctiva

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

8

Cornea

Fibrous transplant layer of clear tissue that extends over the anterior portion of the eyeball. Derived from latin corneous, meaning horny, perhaps because as it protrudes outward, it was thought to resemble a horn.

9

Fovea centralis

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

10

Fundus of the eye

Posterior, inner part of the eye.

11

Iris

Pigmented (colored) layer that opens and closes to allow more and less light into the eye. The central opening of the iris is the pupil.

12

Lens

Transparent, biconvex body behind the pupil of the eye. It bends (refracts) light rays to bring them to focus on the retina.

13

Macula

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

14

Optic chiasm

Point at which optic nerve fibers cross in the brain.

15

Optic disc

Region at the back of the eye where the optic nerve meets he 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.

16

Optic nerve

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

17

Pupil

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

18

Refraction

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 back.

19

Retina

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

20

Rod

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

21

Sclera

Tough, white outer coat of the eyeball.

22

Thalamus

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

23

Vitreous humor

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

24

aque/o

water

25

lephar/o

eyelid

26

conjunctiv/o

conjunctiva

27

cor/o

pupil

28

corne/o

cornea

29

cycl/o

ciliary body or muscle of the eye

30

dacry/o

tears, tear duct

31

ir/o, irid/o

iris (colored portion of the eye around the pupil)

32

kerat/o

cornea

33

lacrim/o

tear

34

ocul/o

eye

35

ophthalm/o

eye

36

opt/o, optic/o

eye, vision

37

palpebr/o

eyelid

38

papill/o

optic disc; nipple-like

39

phac/o, phak/o

lens of the eye

40

pupill/o

pupil

41

retin/o

retina

42

scler/o

sclera (white of the eye); hard

43

uve/o

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

44

vitre/o

glassy

45

ambly/o

dull, dim

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dipl/o

double

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glauc/o

gray

48

mi/o

smaller, less

49

mydr/o

widen, enlarge

50

nyct/o

night

51

phot/o

light

52

presby/o

old age

53

scot/o

darkness

54

xer/o

dry

55

-opia, -opsia

vision

56

-tropia

to turn

57

Cataract

clouding of the lens, causing decreased vision.

58

Chalazion

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

59

Diabetic retinopathy

Retinal effects if diabetic mellitus include microaneurysms, hemorrhages, dilation of retinal veins, and neovascularization (new blood vessels from the retina).

60

Glaucoma

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

61

Hordeolum (stye or sty)

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

62

Macular degeneration

Progressive damage to the macula of the retina.

63

Nystagmus

Repetitive rhythmic movements of one or both eyes.

64

Retinal detachment

Two layers of the retina separate from each other.

65

Strabismus (lazy eye)

Abnormal deviation of the eye.