20: Special Senses: Vision

Question 1

sclera

Answer 1

the outer protective layer is white and fibrous

Question 2

Cornea

Answer 2

The sclera becomes this translucently anteriorly

Question 3

Choroid

Answer 3

middle layer black in color due to absorption of all visible light wavelenghts

Question 4

iris & ciliary body

Answer 4

formed by choroid, structures that surrround the lens of the eye, also intrinsic ( internal eye muscles)

Question 5

lens

Answer 5

surrounded by the iris and ciliary body

Question 6

intrensic

Answer 6

internal eye muscles

Question 7

suspensory ligaments

Answer 7

attach the ciliary body to the edges of the lens

Question 8

pupil

Answer 8

hole in the center of the iris that allows light to enter the eye

Question 9

retina

Answer 9

inner tissue layer of the eye

Question 10

rods

Answer 10

photoreceptor cells, better in dim light, no color, more

Question 11

cones

Answer 11

photoreceptor cells, bright light, color, less

Question 12

accommodation

Answer 12

the ability to correct , move the focal point,

Question 13

emmetropia

Answer 13

the ability to accomodate corectly

Question 14

hyperopia

Answer 14

farshghtedness, eyeball too short, reflective power needs to be increased for distant objects, maximal contactions fail to converge light from near objects, require biconvex lenses

Question 15

Myopia

Answer 15

nearsightedness, eyeball elongated, focal point for distant objects is in front of the lense, lack the ability to diverge, blury distant objects, biconcave lenses

Question 16

Presbyopia

Answer 16

as one ages the ability to accomidate is lost, bifocals required

Question 17

cataract

Answer 17

condition of the lenses that occurs durring ageing, blurry vision due to cloudy lenses, opque distorted

Question 18

Glaucoma

Answer 18

the anterior cavity of the eye, in front of the lense) is filled with aqueous humor, produced faster thatn absorbed, causes blindness, or blury vision

Question 19

aqueous humor

Answer 19

a watery nutrient solution that nourishes the outer lense and inner corneal surfaces

Question 20

scleral venous sinus

Answer 20

canal of schlemm, returns aqueous humor fluids to venous circulation

Question 21

vitreouis humor

Answer 21

not produced continuously, pushed against the posterior of the eye comprimising blood flow and vessels

Question 22

scotopsin

Answer 22

protein found in the rods, combined with visual pigment

Question 23

rhodopsin

Answer 23

combining of visual pigment and scotopsin, when stimulated by light undergo degration backwards

Question 24

hyperpolarization

Answer 24

occurs in nerve cells of the retina as stimulation instead of depolarization

Question 25

light colors

Answer 25

red, green ,blue

Question 26

color lenghts

Answer 26

short to long, blue, green, red

Question 27

retinol

Answer 27

used to allow rods and cones to adapt to light intensity, stored pigment retinal, vitiman A

Question 28

light adaptation

Answer 28

storing retinal as vitiman a in bright light

Question 29

Dark adaptation

Answer 29

stored vitiman a as retinal

Question 30

fovea centralis

Answer 30

less that a square mm, contains only cones with no overlaying cells and is the focal point

Question 31

macula lutea

Answer 31

yellow spot that marks the focal point

Question 32

macular degeneration

Answer 32

due to age, impared focal point, clurry central vision

Question 33

detached retina

Answer 33

major injury, few days before perminate damage

Question 34

optic disk

Answer 34

blind spot, point where the optic nerve is attached, no rods/cones

Question 35

optic chisma

Answer 35

base of brain, optic nerves cross over at this point

Question 36

optic tracts

Answer 36

leade to the visual cortex of the brain, in the posterir cerebral cortex

Question 37

extrinsic volentary skeletal muscles

Answer 37

move the eye volentarily

Question 38

moving parallaz

Answer 38

close objects more more across the retina that distant ones

Question 39

stereopis

Answer 39

binocular vison, shift in location depending on which eye