Eye Anatomy

Question 1

fibrous outer layer of eye contains (2)

Answer 1

sclera + cornea

Question 2

sclera

Answer 2

white of the eye

Question 3

cornea

Answer 3

anterior portion of outer layer, transparent part of eye where light enters

Question 4

middle layer of eye contains (4)

Answer 4

choroid, ciliary body, iris, pupil

Question 5

choroid

Answer 5

• darkly colored, at posterior of eye
• prevents light from dispersing throughout eye
• highly vascular, supplies blood to other layers

Question 6

ciliary body

Answer 6

anterior muscle that changes the shape of the lens so that it can focus

Question 7

iris

Answer 7

• circular, colored part of eye (around pupil)

- dilates + contracts to control amount of light let in thru pupil

Question 8

pupil

Answer 8

• hole in center of iris

- allows light into retina

Question 9

rods

Answer 9

• more numerous photoreceptors in retina

Question 10

retina

Answer 10

sensory portion of eye - contains photoreceptors that send nerve impulses to the brain

Question 11

rods

Answer 11

• more numerous of the 2 photoreceptor types in retina
• stimulated in dim light, more sensitive to light
• responsible for night vision, cannot produce sharp or colored images

Question 12

cones

Answer 12

• other photoreceptor type in retina

- operates in bright light to generate sharp colored images

Question 13

vitreous fluid

Answer 13

gel-like substance filling vitreous body, holds retina to choroid in suspended position

Question 14

aqueous humor

Answer 14

liquid that fills spaces between cornea + lens

Question 15

extrinsic eye muscles (6)

Answer 15

1. medial rectus
2. inferior rectus
3. superior rectus
4. lateral rectus
5. inferior oblique
6. superior oblique

Question 16

medial rectus

Answer 16

• innervated by CN III

- turns eye medially

Question 17

inferior rectus

Answer 17

• innervated by CN III
• moves eye medially
• depresses eye

Question 18

superior rectus

Answer 18

• innervated by CN III
• moves eye medially
• elevates eye

Question 19

lateral rectus

Answer 19

• innervated by CN VI

- turns eye laterally

Question 20

inferior oblique

Answer 20

• innervated by CN III
• elevates eye
• laterally + externally rotates eye

Question 21

superior oblique

Answer 21

• innervated by CN IV
• depresses eye
• laterally + internally rotates eye