vision quiz

Question 1

What are the five special senses?

Answer 1

vision, taste, smell, hearing, equilibrium

Question 2

what are the five major structures in the eye?

Answer 2

eyebrows, eyelids, conjunctiva, lacrimal apparatus, extrinsic eye muscles

Question 3

eyebrow function

Answer 3

protection from sunlight and perspiration

Question 4

eyelid function

Answer 4

contains eyelashes which initiate blinking, contains tarsal and ciliary glands

Question 5

conjunctiva function

Answer 5

protects and lubricates the eye (mucous membrane), acts as a barrier between sclera and outside threats

Question 6

lacrimal apparatus function

Answer 6

lacrimal secretion (tears)

Question 7

extrinsic eye muscle function

Answer 7

eye movement

Question 8

describe the flow of tears

Answer 8

tears form in lacrimal gland and flow to excretory ducts, tears fill eyes then drain through lacrimal punctum, flow to lacrimal canaliculus, down nasal passage through nasolacrimal duct then end in the inferior meatus of nasal cavity

Question 9

name the extrinsic eye muscles

Answer 9

lateral rectus, medial rectus, superior rectus, inferior rectus, superior oblique, inferior oblique

Question 10

lateral rectus innervation and action

Answer 10

moves eye laterally, VI (abducens)

Question 11

medial rectus innervation and action

Answer 11

medial eye movement, III (oculomotor)

Question 12

superior rectus innervation and action

Answer 12

elevates and turns eye medially, III (oculomotor)

Question 13

inferior rectus innervation and action

Answer 13

depresses and turns eye medially, III (oculomotor)

Question 14

superior oblique innervation action

Answer 14

elevates and turns eye laterally, IV (trochlear)

Question 15

inferior oblique innervation and action

Answer 15

elevates and turns eye laterally, III (oculomotor)

Question 16

infected tarsal gland, leading to cyst

Answer 16

chalazion

Question 17

aqueous humor drainage is blocked, compressing retina and optic nerve

Answer 17

glaucoma

Question 18

Double vision caused by bilateral extrinsic eye muscles not being coordinated

Answer 18

diplopia

Question 19

“cross-eyed”, extrinsic eye muscle weakness causing eye rotation opposite of weakness

Answer 19

strabismus

Question 20

name the layers and compartments of the eyeball

Answer 20

fibrous layer- sclera and cornea
vascular layer- choroid, ciliary body, iris
inner layer- retina

Question 21

what liquids fill each segment?

Answer 21

anterior segments- aqueous humor
posterior segments- vitreous humor

Question 22

what muscles contract or dilate during close vision?

Answer 22

ciliary muscles and sphincter pupillae contract, pupils constrict

Question 23

what muscles contract or dilate during far vision?

Answer 23

ciliary muscles relax, dilator pupillae contracts, pupil dilates

Question 24

three types of neural cells in retina

Answer 24

photoreceptors, bipolar cells, ganglion cells

Question 25

photoreceptor function

Answer 25

first in light process, rods and cones, detects light and transmits signals to brain

Question 26

bipolar cell function

Answer 26

receive input from photoreceptors and transmit them to ganglion cells, second step

Question 27

ganglion cell function

Answer 27

final step, collects input from photoreceptors and exits to brain via optic nerve

Question 28

What is the optic disk and why is it there?

Answer 28

blind spot in back of eye to allow passageway for optic nerve to reach the occipital lobe in brain, lacks photoreceptors

Question 29

compare and contrast rods and cones

Answer 29

rods- greyscale, dim light, low resolution, more numerous and sensitive cones- vibrant colors, bright light, high resolution, less common and sensitive

Question 30

What is the macula lutea

Answer 30

lateral to blind spot, mostly cones

Question 31

What is the fovea centralis

Answer 31

center of macula lutea, all cones, best visual activity

Question 32

Two blood supplies to eyeball?

Answer 32

choroid, central artery/vein

Question 33

clumps of crystallin proteins over lens, caused by aging/diabetes/smoking/UV exposure, can cause increased risk of glaucoma, eye inflammation, vision loss if left untreated

Answer 33

cataracts

Question 34

pathway of light entering eye

Answer 34

1. cornea 2. aqueous humor 3. lens 4. vitreous humor 5. neural layer of retina 6. photoreceptors

Question 35

what is an emmetropic eye

Answer 35

normal eye/ 20-20 vision

Question 36

What are the three steps necessary for close vision?

Answer 36

accommodation of the lenses, constriction of the lenses (pupillary reflex), convergence of the eyeballs

Question 37

what is myopia?

Answer 37

near-sightedness, caused by eyeball length too long or focal point located in front of retina, corrected with concave lens

Question 38

what is hyperopia?

Answer 38

far-sightedness, caused by eyeball length too short or focal point behind retina, corrected with convex lens

Question 39

what is presbyopia?

Answer 39

lens hardening with age, leads to near vision being blurry/lost

Question 40

what is astigmatism?

Answer 40

unequal curvature in different parts of the cornea or lens, leads to light scattering across the retina

Question 41

What does it mean when someone is red-green colorblind?

Answer 41

Red or green cones are absent in photoreceptors, causing the two colors to be mistaken for each other

Question 42

Do photo receptors generate generator potentials or action potentials?

Answer 42

Generator potentials

Question 43

What is the visual pathway from the eye to the occipital lobe of the brain?

Answer 43

Optic tract

Question 44

What happens to the fibers leaving the medial retinal field?

Answer 44

Medial fibers will cross over

Question 45

What function do the neurons in the Suprachiasmatic Nucleus help with? What about the Pretectal Nuclei? Superior Colliculi?

Answer 45

Suprachiasmatic nucleus- daily biorhythms Pretectal nuclei- pupillary nuclei Superior colliculi- extrinsic eye muscles

Question 46

How is depth perception accomplished? What happens if there is no input from one eye?

Answer 46

Both eyes focus on the same object and see it from slightly different angles, brain processes these signals to create perception. Both eyes have to be coordinated, or the perception will not be accurate

Question 47

What is Nyctalopia?

Answer 47

night blindness caused by diminished rod function

Question 48

What is Retinitis Pigmentosa?

Answer 48

A group of genetic disorders called inherited retinal dystrophy, causes vision loss