eye

Question 1

external landmarks (sclera, cornea, iris, pupil)

Answer 1

eyelids (palpebrae)

Question 2

whites of the eye

• posterior 5/6 of eye
• function: provides shape to eyeball and protects inner parts

Answer 2

sclera

Question 3

transparent; in front of iris (center part)

• curved transparent structure anterior to iris and pupil
• anterior 1/6 of the eye
• function: admits and refracts (bends) light

Answer 3

cornea

Question 4

pigmented part of the eye
- contains pupil
- function: regulates the amount of light entering the eye (by dilating and constricting

Answer 4

iris

Question 5

opening in iris

Answer 5

pupil

Question 6

lining sclera and eyelid

function: secrete mucus as lubricant for eye/eyelids

Answer 6

conjunctiva

Question 7

inflammation of conjunctiva (“pink eye”)

Answer 7

conjunctivitis

Question 8

produces/collects tears

Answer 8

lacrimal apparatus

Question 9

tears

Answer 9

lacrimal fluid

Question 10

produces and secretes tears

Answer 10

lacrimal gland

Question 11

t/f: fluid is swept across the surface of the eye by the eyelids

Answer 11

true

Question 12

from lacrimal puncta (hole) to nasolacrimal duct

Answer 12

lacrimal canaliculi

Question 13

drains tears into nasal cavity, where they are eventually swallowed

Answer 13

nasolacrimal duct

Question 14

why do tears spill onto the cheek when someone gets a runny nose?

Answer 14

• tears overwhelm the system (lacrimal apparatus)
• too many tears to collect - overflow the eyelids
• nasolacrimal duct pours lots of tears into nasal cavity - runny nose

Question 15

moves eye medially (adducts)
- eye moves toward nose

Answer 15

medial rectus

Question 16

moves eye laterally (abducts)
- eye moves toward ear

Answer 16

lateral rectus

Question 17

elevates eye and moves eye medially

Answer 17

superior rectus

Question 18

depresses eye and moves eye medially

Answer 18

inferior rectus

Question 19

depresses and moves eye laterally

Answer 19

superior oblique

Question 20

elevates eye and moves eye laterally

Answer 20

inferior oblique

Question 21

what nerve innervates the medial rectus, superior rectus, inferior rectus, inferior oblique?

Answer 21

oculomotor nerve

Question 22

what nerve innervates the superior oblique?

Answer 22

trochlear nerve

Question 23

what nerve innervates the lateral rectus?

Answer 23

abducens nerve

Question 24

• biconvex, transparent structure inside ball
• function: changes shape (flat or round) to focus light rays
• held in place by suspensory ligaments

Answer 24

lens

Question 25

avascular - contains sclera and cornea

Answer 25

fibrous (external) tunic

Question 26

a laser removes cells from part of the cornea to change its shape - to better focus the light where needed

Answer 26

laser vision correction

Question 27

dark brown membrane - function: contains blood vessels that help nourish the retina

Answer 27

choroid

Question 28

ring of smooth muscle tissue that surrounds the lens - attaches to the lens via suspensory ligaments - function: as the smooth muscle contracts, the suspensory ligaments relax to make the lens more round - produces aqueous humor

Answer 28

ciliary body

Question 29

to see close up, ciliary muscles contract, suspensory ligaments relax, and lens becomes thicker

Answer 29

accommodation

Question 30

posterior 3/4 of eye - one of the few places bipolar neurons can be found - consists of pigmented and neural layer

Answer 30

retina

Question 31

outer layer adjacent to choroid functions: - absorbs excess light to prevent reflection/glare - provides vitamin a to photoreceptors

Answer 31

pigmented layer

Question 32

inner layer - function: its photoreceptors receive light information and convert it to nerve impulses that are sent via optic nerve (CN II) to the brain

Answer 32

neural layer

Question 33

what are the two types of photoreceptors?

Answer 33

rods and cones

Question 34

low (reduced) light, black and white (more than cones)

Answer 34

rods

Question 35

require more light, color

Answer 35

cones

Question 36

blind spot; area where the optic nerve exits the eye; contains no photoreceptors

Answer 36

optic disc

Question 37

lateral to optic disc; in center is fovea centralis

Answer 37

macula lutea (yellow spot)

Question 38

sharpest vision (only cones)

Answer 38

fovea centralis

Question 39

light focused in front of retina

Answer 39

nearsightedness

Question 40

light focused behind the retina

Answer 40

farsightedness

Question 41

fluid collects between the pigmented layer and neural layer (can cause blindness)

Answer 41

detached retina

Question 42

- between cornea and lens - separated into anterior and posterior chambers by the iris - filled with aqueous humor

Answer 42

anterior cavity

Question 43

supplies nutrients, removes wastes for lens and cornea, and is continually produced and replaced

Answer 43

aqueous humor

Question 44

- aqueous humor is secreted by the ciliary processes into the posterior chamber - aqueous humor moves from the posterior chamber, through the pupil to the anterior chamber - excess aqueous humor is resorbed via the scleral venous sinus

Answer 44

flow of aqueous humor

Question 45

- between lens and retina - contains vitreous humor

Answer 45

posterior cavity

Question 46

helps maintain the shape of the eye and keeps the retina against the choroid; is not continually produced

Answer 46

vitreous humor

Question 47

- light rays enter the eye through the cornea and are refracted (bent) - light rays are further refracted by the lens (flattened = far vision, rounded = near) - light rays focus on retina - light ray information is converted to nerve impulses by photoreceptors (rods and cones) - nerve impulses transmitted to the brain via CN II (optic nerve) - from the optic nerves, visual information passes to the optic chiasm then to the optic tract, to the thalamus, and then to the primary visual cortex of the occipital lobe

Answer 47

how visual information is processed