Exam 3: Eye

Question 1

Palpebrae

Answer 1

-eyelids

Question 2

External Landmark: Sclera

Answer 2

-whites of the eye

Question 3

External Landmark: Cornea

Answer 3

-transparent center part in front of the iris

Question 4

External Landmark: Iris

Answer 4

-pigmented part of eye

Question 5

External Landmark: Pupil

Answer 5

-opening of iris

Question 6

Conjunctiva

Answer 6

• lines sclera and eyelid

- function: secretes mucus as a lubricant

Question 7

Conjuctivitis

Answer 7

• pink eye

- imflamed conjunctiva

Question 8

Lacrimal Apparatus (function, structures, contents)

Answer 8

• produces/collects tears (lacrimal fluid)
• consists of lacrimal gland, lacrimal canaliculi, lacrimal puncti, and nasolacrimal duct
• contains water, sodium ions, antibodies (fight infections, lysozyme-antibacterial agent)

Question 9

Lacrimal Gland

Answer 9

-produces and secretes tears

Question 10

Lacrimal Canaliculi

Answer 10

• from lacrimal puncti to nasal lacrimal duct

- drain tears

Question 11

Nasolacrimal Duct

Answer 11

• internal

- drains tears into nasal cavity, where they are eventually swallowed

Question 12

Why do you get a runny nose when you cry?

Answer 12

-overproduction of tears overflows system

Question 13

Medial Recuts

Answer 13

-moves eye medially (adducts)

Question 14

Lateral Rectus

Answer 14

-moves eye laterally (abducts)

Question 15

Superior Rectus

Answer 15

-elevates and moves eye medially (adducts)

Question 16

Inferior Rectus

Answer 16

-depresses and moves eye medially (adducts)

Question 17

Superior Oblique

Answer 17

• depresses (pupil moves inferiorly) and moves eye laterally

- attaches to superior posterior part of eye

Question 18

Inferior Oblique

Answer 18

• elevates (pupil moves superiorly) and moves eye laterally

- attaches to inferior posterior part of eye

Question 19

Website to help learn eye movements

Answer 19

anatomy.hsc.wvu.edu/ReillyDental/VirtualPatients/ExtraocularSkeletalMuscle.swf

Question 20

Lens

Answer 20

• biconvex, transparent structure inside eyeball
• function: refracts light rays
• held in place by suspensory ligaments

Question 21

Suspensory Ligaments

Answer 21

-actually change shape of lens due to what type of vision
How?
-when taut, make lens fatter for far vision
-when looser, make lens ‘puffier’ for near vision

Question 22

Fibrous Tunic

Answer 22

• avascular

- made up of sclera and cornea

Question 23

Sclera (Function)

Answer 23

-supports and maintains eye shape

Question 24

Cornea (Structure)

Answer 24

-curved transparent structure anterior to iris and pupil

Question 25

Vascular Tunic

Answer 25

- contains blood vessels to nourish eye | - consists of choroid, cilliary body, and iris (listed posterior to anterior)

Question 26

Choroid

Answer 26

- dark brown membrane | - function: refracts light rays

Question 27

Cillary Body

Answer 27

- ring of smooth muscle tissue that surrounds the lens - attaches to lens via suspensory ligaments - functions: changes pull on suspensory ligaments and secretes aqueous humor - far vision: cilliary relaxes, suspensory tight - near vision: cillary contract, suspensory loose

Question 28

Aqueous Humor

Answer 28

- fluid very similar to CSF in composition and function - brings nutrients in and removes waste - drains into dural venous sinuses

Question 29

Iris

Answer 29

- pigmented colored part of eye - contains pupil - function: constricts or dilates pupil to regulate amount of light entering eye

Question 30

Retina

Answer 30

- converts light rays to nerve impulses | - consists of pigmented layer and neural layer

Question 31

Pigmented Layer

Answer 31

- outer layer of retina adjacent to choroid | - function: absorb stray light rays

Question 32

Neural Layer

Answer 32

- inner layer of retina - function: its photoreceptors receive light information and convert it into nerve impulses that are sent, via CN II (optic nerve) to the brain - 2 types: rods and cones

Question 33

Rods

Answer 33

- work in dim/low light | - image fuzzy not very sharp

Question 34

Cones

Answer 34

- work in bright light, produce clear, sharp image | - perceive color

Question 35

Glaucoma

Answer 35

- buildup of pressure in space containing aqueous humor - 1 cause: increased pressure in space-not draining properly (too much aqueous humor) - can cause blindess

Question 36

Optic Disc (Blind Spot)

Answer 36

- area where the optic nerve exists the eye | - contains no photoreceptors-only axons

Question 37

Macula Lutea

Answer 37

- lateral to optic disc | - in center is Fovea Centralis

Question 38

Fovea Centralis

Answer 38

- area of sharpest vision | - only cones (so needs light)

Question 39

Anterior Cavity

Answer 39

- between cornea and lens | - filled with aqueous humor

Question 40

Posterior Cavity

Answer 40

- between lens and retina | - contains vitreous humor

Question 41

Vitreous umor

Answer 41

- gelatinous-helps maintain shape of eye - not constantly made - have same amount since birth

Question 42

Pathway of Processing Visual Information

Answer 42

- light rays enter eye through cornea and are refracted - light rays are further refracted by lens - light rays focus on retina - light ray information is converted to nerve impulses by photoreceptors - nerve impulses transmitted to the brain via CN II (Optic Nerve)

Question 43

LASIK Eye Surgery

Answer 43

-reshape cornea with laser