Chapter 19: Special Senses Part II (Vision) SYDNEY

Question 1

superficial anatomy of the eye

Answer 1

-superior & inferior palpebrae
-medial & lateral palpebral comissures
-pupil
-iris

Question 2

what are the palpebrae?

Answer 2

eyelids

Question 3

provide a superficial covering over its anterior exposed surface

Answer 3

conjunctiva

Question 4

where are the eyelids united at?

Answer 4

medial and lateral palpebral commissures

Question 5

parts of the conjunctivial sac

Answer 5

-specialized bursa
-bulbar & palpebral conjuctivia
-covers sclera

Question 6

parts of the lacrimal apparatus

Answer 6

-lacrimal gland
-lacrimal ducts
-lacrimal canaliculi
-nasolacrimal ducts

Question 7

located within the superolateral depression of each orbit

Answer 7

lacrimal gland

Question 8

drains lacrimal fluid into a rounded lacrimal sac

Answer 8

lacrimal canaliculi

Question 9

what is lacrimal fluid

Answer 9

commonly known as tears

Question 10

receives the lacrimal fluid from the lacrimal sac

Answer 10

nasolacrimal duct

Question 11

3 layers of the eyeball

Answer 11

-fibrous layer
-vascular layer
-inner layer (retina)

Question 12

parts of the fibrous layer

Answer 12

-sclera
-cornea

Question 13

part of the outer layer that is called the “white” of the eye

Answer 13

sclera

Question 14

forms the anterior surface of the fibrous tunic

Answer 14

cornea

Question 15

features of the sclera

Answer 15

-covers 5/6 of eyeball
-opaque, white (irregular fibers)
-attachment for muscles
-has blood vessels

Question 16

features of the cornea

Answer 16

-convex anterior to iris/pupil
-transparent
-completely avascular

Question 17

meaning of the cornea being completely avascular

Answer 17

nourishment from ringing capillaries, aqueous humor and tears

Question 18

parts of the vascular layer

Answer 18

-choroid
-ciliary body
-iris
-pupil

Question 19

most extensive and posterior region of the vascular tunic & lines most of sclera

Answer 19

choroid

Question 20

located anterior to the choroid

Answer 20

ciliary body

Question 21

features of the ciliary body

Answer 21

-attaches the lens
-controls lens focus
-ciliary processes secrete aqueous humor

Question 22

what type of muscles does the iris have?

Answer 22

involuntary muscles

Question 23

two groups of smooth muscle layers

Answer 23

-sphincter pupillae
-dilator pupillae

Question 24

what is the sphincter pupillae controlled by?

Answer 24

-under the control of parasympathetic division of the ANS
-constricts the pupil

Question 25

what is the dilator pupillae controlled by?

Answer 25

controlled by the sympathetic division of the ANS to dilate the pupil

Question 26

center of the iris is a black hole called

Answer 26

pupil

Question 27

parts of inner layer of retina

Answer 27

-optic part -non-visual part -optic disc -macula lutea -fovea centralis

Question 28

what is the optic part of the retina sensitive to

Answer 28

sensitive to light

Question 29

2 layers of the retina

Answer 29

-neural layer -pigmented layer

Question 30

parts of the neural layer

Answer 30

-light receptors -rods -cones

Question 31

function of pigmented layer

Answer 31

limits light scattering

Question 32

function of the rods

Answer 32

dim light

Question 33

function of the cones

Answer 33

-bright light -color

Question 34

what is the non-visual part of the inner layer retina

Answer 34

anterior extension of pigmented layer

Question 35

axons extend from the ganglionic cells into and through the _____

Answer 35

optic disc

Question 36

features of the optic disc

Answer 36

-vessels/optic nerve entry -no photoreceptors

Question 37

yellowish region of the neural layer

Answer 37

macula lutea

Question 38

within the macula lutea is a pit called the _____

Answer 38

fovea centralis

Question 39

feature of the macula lutea

Answer 39

high cone density

Question 40

feature of the fovea centralis

Answer 40

highest visual acuity

Question 41

clinical significance of red eye

Answer 41

-capillary lamina of choroid -supplies rods & cones of retina -highest perfusion rate in body

Question 42

clinical significance of retinal detachment

Answer 42

-neural and pigmented layers not firmly attached -neural layer can separate and drop

Question 43

contents of the eyeball

Answer 43

-aqueous humor -vitreous humor

Question 44

what is the aqueous humor?

Answer 44

fluid in the anterior cavity

Question 45

function of aqueous humor

Answer 45

a filtrate of plasma that resembles CSF and is produced by the epithelium covering the ciliary body

Question 46

features of the aqueous humor

Answer 46

-absorbed by scleral venous sinus -nourishes cornea -intraocular pressure

Question 47

what does the intraocular pressure do?

Answer 47

provide balance

Question 48

posterior cavity is occupied by the transparent, gelatinous ______

Answer 48

vitreous humor

Question 49

features of the vitreous humor

Answer 49

-fluid enclosed in vitreous -posterior chamber (4/5 of eyeball) -jelly-like -supports retina & lens

Question 50

clinical significance of glaucoma

Answer 50

reduction of rate of aqueous humor outflow to scleral venous sinus

Question 51

features of glaucoma

Answer 51

-results in pressure buildup in both chambers -compression of the retina -blindness

Question 52

appearance of lens

Answer 52

-transparent, biconvex -enclosed by the capsule of lens

Question 53

attaches to the lens capsule at its periphery, where they transmit tension that enables the lens to change shape

Answer 53

suspensory ligament

Question 54

links to ciliary processes

Answer 54

suspensory ligament

Question 55

tension in the suspensory ligaments varies according to the contraction and relaxation of the ______

Answer 55

ciliary muscles

Question 56

what happens when the ciliary muscles relax?

Answer 56

-the ciliary body moves away from the lens (far vision), so the tension on the suspensory ligaments increases -flattened lens -default position of lens

Question 57

what happens when the ciliary muscles contract?

Answer 57

-the ciliary body moves near the lens (near vision) and lens becomes relaxed -more round

Question 58

process of making the lens more spherical to view close-up objects

Answer 58

accommodation

Question 59

what is the accommodation controlled by

Answer 59

parasympathetic division of the ANS

Question 60

what happens during presbyopia?

Answer 60

-lens beomes harder/ flatter with age -reduced focusing power

Question 61

area of opacity

Answer 61

cataracts

Question 62

combined surgeries of cataracts

Answer 62

-remove opacities -insert new lens

Question 63

what do the extra-ocular muscles of the eye do?

Answer 63

move superior eyelids and eyeball