chapter17 part2 p572-4

Question 0

what two small pores drain the lacrimal lake?

Answer 0

lacrimal puncta

Question 1

tears accumulate at the medial canthus in an area known as

Answer 1

lacrimal lake

Question 2

The tears from lacrimal lake drain in to

Answer 2

lacrimal canaliculi

Question 3

lacrimal canaliculi leads to

Answer 3

lcarimal sac

Question 4

which duct delivers tears from lacrimal sac? to where?

Answer 4

nasolacrimal duct, nasal cavity on that side

Question 5

The nasolacrimal duct empties into

Answer 5

inferior meatus

Question 6

narrow passageway inferior and lateral to the inferior nasal concha

Answer 6

inferior meatus

Question 7

tears stream across face when

Answer 7

lacrimal puncta can’t provide neough drainage

Question 8

what cushions and insulates the eye?

Answer 8

orbital fat

Question 9

name 3 distinct layers in the wall of the eye

Answer 9

1. outer fibrous layer
2. intermediate vascular layer/uvea
3. deep inner layer/retina

Question 10

The wall of the eyes was formerly called

Answer 10

tunics

Question 11

other name for visual receptors

Answer 11

photoreceptors

Question 12

eyeball is filled with

Answer 12

fluid

Question 13

eyeball cavities can be divided into what 2 cavities?

Answer 13

anterior and posterior

Question 14

anterior cavity has which 2 chambers and where are they located

Answer 14

anterior chamber- between cornea and colored iris

posterior chamber - between iris and lens

Question 15

anterior cavity is filled with

Answer 15

aqueous humor

Question 16

other name for posterior cavity

Answer 16

vitreous chamber

Question 17

posterior cavity contains

Answer 17

vitreous body

Question 18

describe vitreous body

Answer 18

gelatinous substance

Question 19

describe aqueous humor

Answer 19

clear, watery fluid

Question 20

fluid part of vitreous body is called

Answer 20

vitreous humor

Question 21

What is a function of the vitreous body and aqueous humor?

Answer 21

stabilization of shape of the eye

Question 22

the outermost layer of the eye is called

Answer 22

fibrous layer

Question 23

2 components of the fibrous layer are

Answer 23

sclera and cornea

Question 24

what are the 3 functions of the fibrous layer

Answer 24

1. support and protect 2. serve as attachment site for extrinsic eye muscles 3. contains structures that assist in focusing

Question 25

white of the eye

Answer 25

sclera

Question 26

The sclera consists of a dense fibrous connective tissue containing what 2 components?

Answer 26

collagen and elastic fibers

Question 27

The sclera layer is thickest at what part

Answer 27

posterior surface of the eye, near the exit of the optic nerve

Question 28

which part is the sclera the thinnest?

Answer 28

anterior surface

Question 29

the 6 extrinsic eye muscles insert on the sclera blending their ________ with those of the __________ layer

Answer 29

collagen fibers, fibrous layer

Question 30

The surface of the sclera contains __________ and _________ that penetrate the sclera to reach the internal structures

Answer 30

small blood vessels and nerves

Question 31

The transparent __________ is structurally continuous with the sclera

Answer 31

cornea

Question 32

What is the corneal limbus

Answer 32

border between transparent cornea and sclera

Question 33

Deep to the corneal epithelium, cornea consists primarily of dense matrix containing multiple layers of ___________

Answer 33

collagen fibers

Question 34

deep in corneal epithelium, how are the multiple layers of collagen fibers organized

Answer 34

to not interfere with the passage of light

Question 35

Cornea has no _________

Answer 35

blood vessels

Question 36

How does cornea obtain oxygen and nutrients?

Answer 36

diffusion from the tears that flow across the surfaces

Question 37

What is the most sensitive portion of the eye and why?

Answer 37

cornea - numerous free nerve endings

Question 38

corneal ability to repair itself is

Answer 38

restricted- injuries must be treated immediately

Question 39

Most common form of transplant surgery

Answer 39

corneal transplant

Question 40

why can corneal transplant happen between unrelated individuals?

Answer 40

no blood vessels to carry white blood cells

Question 41

pigmented region of the eye that includes 3 components = name the region and the 3 components

Answer 41

vascular layer/uvea | contains iris, ciliary body, choroid

Question 42

Name 3 tissue structures included in the vascular layer/uvea

Answer 42

1. blood vessels 2. lymphatic vessels 3. intrinsic/smooth muscles of the eye

Question 43

Name 4 functions of the vascular layer/uvea

Answer 43

1. provide route for blood vessels and lymphatics that supply tissues of the eye 2. regulate the amount of light that enters the eye 3. secretes and reabsorbs the aqueous humor that circulates within the chambers of the eye 4. controls the shape of the lense- part of focusing

Question 44

lris contains which types of tissue/cells? (3)

Answer 44

1. blood vessels 2. pigment cells 3. 2 layers of smooth muscle fibers

Question 45

What are the 2 layers of smooth muscle fibers called in the iris?

Answer 45

pupillary muscles

Question 46

What do the pupillary muslces control?

Answer 46

contract- change diameter of the pupil.

Question 47

central opening of the iris is

Answer 47

pupil

Question 48

What are the 2 types of pupillary muscles?

Answer 48

dilators and constrictors

Question 49

Which nervous system controls the 2 pupillary muscle groups?

Answer 49

autonomic nervous system

Question 50

parasympathetic activation causes what in pupils- this is called what

Answer 50

contriction, consensual light reflex

Question 51

sympathetic activation of the pupils cause what?

Answer 51

dilation of the pupils

Question 52

body of the iris consists of what type of tissue?

Answer 52

highly vascular, pigmented, loose connective tissue

Question 53

which part of the iris has no epithelial covering?

Answer 53

anterior surface

Question 54

The anterior surface of the iris is covered by what?

Answer 54

incomplete layer of fibroblasts and melanocytes

Question 55

What is scattered within the body of the iris?

Answer 55

melanocytes

Question 56

What is the posterior surface of iris covered by?

Answer 56

pigmented epithelium that is part of the inner layer and contains melanin granules

Question 57

disease of the retina

Answer 57

retinopathy

Question 58

what develops in many people with diabetes mellitus

Answer 58

diabetic retinopathy

Question 59

leading cause of blindness in US

Answer 59

ldiabetic retinoathy

Question 60

diabetic retinopathy results from

Answer 60

blockage of small retinal blood vessels, followed by excessive growh of abnormal blood vessels

Question 61

What do the growth of abnormal blood vessels do in diabetic retinopathy?i

Answer 61

they invade the retina/inner layer and extend into the space between its 2 parts - outer pigmented part and inner neural part, causing loss of visual acuity from the damage to photoreceptors that are deprived of oxygen and nutrients. the blood leaks into posterior cavity

Question 62

What is a possible treatment for the vessel growth in diabetic retinopathy?

Answer 62

laser therapy0 seal leaking vessels and block new vessel growth. The posterior cavity can be drained and the cloudy fluid replaced by clear substitute= vitrectomy

Question 63

Where do photoreceptors get oxygen and nutreints from?

Answer 63

Blood vessels in the choroid- diffusion

Question 64

What is a detached retina?

Answer 64

neural part of the retina becomes separated from the pigmented part

Question 65

What are possible causes of detached retina?

Answer 65

sudden hard impact to the eye

Question 66

What is a possible treatment for detached retina?

Answer 66

welding parts together with laser beams focused through cornea- heat and fuse 2 parts together - produce permanent blind spots

Question 67

What makes eyes blue?

Answer 67

connective tissue of the iris contains few melanocytes- light passes through it and bounces off the pigmented epithelium

Question 68

What makes green, brown, black eyes?

Answer 68

increasing numbers of melanocytes in the body and surface of the iris

Question 69

Genes determining eye color affect which parts of the body?

Answer 69

anterior surface and interior of the iris | density of the pigmented epithelium