15.1

Question 1

What are the Accessory Structures?

Answer 1

eyebrows
eyelids
conjunctiva
lacrimal apparatus
extrinsic eye muscles
eyeball

Question 2

what is the conjunctiva and what is its function

Answer 2

it is a transparent mucus membrane that produces a lubricating mucus that prevents the eye from drying out

Question 3

what is the lacrimal apparatus

what is its function

Answer 3

consists of the lacrimal glands and small ducts
lacrimal gland secretes tears
small ducts drain excess fluid into the nasolacrimal duct

Question 4

what is lacrimal fluid and its function

Answer 4

contain mucus, antibodies and lysozyme to cleanse moisten and protect the eye

Question 5

what are the 3 layers of the eye

Answer 5

fibrous
vascular
inner layers/tunics

Question 6

what are the parts of each eye layer

Answer 6

fibrous - sclera and cornea
Vascular - choroid, ciliary body, and iris
Tunics - retina

Question 7

what liquid is in the posterior segment

Answer 7

vitreous humour - transmits light, supports the posterior surface of the lens, holds the retina firmly against the pigmented layer, contributes to intraocular pressure

Question 8

what liquid is in the anterior segement

Answer 8

aqueous humour - supplies nutrients and oxygen to the lens and cornea while carrying away wastes

Question 9

what is glaucoma

Answer 9

drainage of aqueous humour is blocked causing a raise in pressure

Question 10

what are cataracts

Answer 10

clouding of lens due to insoluable proteins

Question 11

when the lens changes shape to account for things far away does it become thick or thin? how about when things are close?

Answer 11

thin

thick

Question 12

what is the difference between distant and far point vision

Answer 12

distant - lens is flattened maximally

far point - the point in which the lens can no longer change shape

Question 13

what are the three types of adjustments made for close vision

Answer 13

accommodation of the lens
constriction of the pupils
convergence of the eyeballs

Question 14

what occurs at the maximal thickening of the lens

Answer 14

near point vision

Question 15

what is myopia

how is it fixed

Answer 15

when lens is too thick or eyeball is too long; seeing close objects without a problem, but far objects blurred
concave lens

Question 16

what is hyperopia

how is it fixed

Answer 16

when lens is too thin or eyeball is too short; seeing distant objects clearly but close objects blurred
convex lens

Question 17

what is astigmatism

Answer 17

uneven curvatures of the cornea or lens

Question 18

what is the pathway of light to the retina

Answer 18

cornea, aqueous humour, lens, vitreous humour, entire neural layer of retina, photoreceptors

Question 19

when something is far away are the ciliary muscles relaxed or contracted? how about when something is close

Answer 19

relaxed

contracted

Question 20

when something is far away are the suspensory ligaments stretched or loosenedd? how about when something is close

Answer 20

stretched

loosened

Question 21

what lenses are used to correct myopia, how about hyperopia

Answer 21

diverging, converging

Question 22

what are the differences between rods and cones

Answer 22

rods are highly sensitive, best suited for night vision, see black and whites
cones less sensitive, best for bright visual activity, colour vision

Question 23

what is the fovea centralis

Answer 23

area only containing cones and is the region of best visual acuity