EYEBALL

Question 1

What are the names of the layers of the eyeball?

Answer 1

fibrous tuinc, uveal tract, & retina

Question 2

What are the parts of the uveal tract of the eyeball?

Answer 2

iris, ciliary body, choroid, & pupil

Question 3

Define each: iris, ciliary body, choroid, and pupil. (not highlighted)

Answer 3

Iris: pigmented epithelial region of uveal tract of eyeball, gives color of eye
Ciliary body: part of the uveal tract containing ciliaris muscle
Choroid: vascular part of uveal tract next to retina
Pupil: opening in center of iris; gives black spot in eyeball

Question 4

What are the receptor neurons of the second cranial nerve?

Answer 4

rod and cone photoreceptor cells

Question 5

What is the function of the rod cell?

Answer 5

provide vision in dim light conditions

Question 6

What is the function of the cone cell?

Answer 6

provide vision in bight light conditions and mediate color vision

Question 7

What is the most numerous photoreceptor cell?

Answer 7

rod cell

Question 8

What forms the optic nerve?

Answer 8

axons of ganglion cells

Question 9

What is the location of the anterior chamber of the eyeball?

Answer 9

between the cornea and iris

Question 10

What is the location of the posterior chamber of the eyeball?

Answer 10

between the iris and lens

Question 11

What is contained in the anterior chamber of the eyeball?

Answer 11

aqueous humor

Question 12

What is contained in the posterior chamber of the eyeball?

Answer 12

aqueous humor

Question 13

What is the name given to the chamber behind the lens?

Answer 13

vitreous chamber

Question 14

What is the location of the virtuous chamber?

Answer 14

behind the lens, in front of the retina

Question 15

What fills the vitreous chamber?

Answer 15

vitreous body

Question 16

What are the functions of the vitreous body?

Answer 16

maintain retinal curvature; allow minimal light distortion from lens to retina

Question 17

What are the common characteristics in origin and insertion of all rectus extra ocular muscles?

Answer 17

they all originate from a common annular tendon in the orbit;
they all insert into the sclera in front of the coronal equator of the eyeball

Question 18

What is the common characteristic regarding the insertion of both oblique extra ocular muscles?

Answer 18

both insert onto sclera on the lateral margin of the eyeball behind the coronal equator

Question 19

What is the source of innervation of the specific intrinsic eye muscles?

Answer 19

parasympathetic fibers from oculomotor nerve–ciliaris, sphincter papillae;
sympathetic fibers from internal carotid artery plexus–dilator papillae

Question 20

What are the two unique features of the fourth cranial nerve?

Answer 20

1) it is the only cranial with an apparent origin form the dorsal surface of the brain;
2) it is th only cranial efferent nerve to decussate within the midbrain from its nucleus

Question 21

Visceral efferent fibers conveyed in the third cranial nerve originate from which nucleus?

Answer 21

accessory oculomotor nucleus of Edinger/Westphal

Question 22

What is the location of synapse for preganglionic parasympathetic efferent fibers of the third cranial nerve?

Answer 22

ciliary ganglion

Question 23

Postganglionic parasympathetic efferent fibers of the third cranial nerve are carried in which nerve?

Answer 23

short ciliary nerve

Question 24

What is unique about the vascular supply of the retina?

Answer 24

a single vessel supplies it

[central artery of the retina]

Question 25

What vessel supplies the inner tunic of the eyeball?

Answer 25

central artery of the retina