Structures of the Eyes

Question 1

Define the adnexa and its parts

Answer 1

the adnexa are the structures outside of the eyeball. This includes the orbit, eye muscles, eyelid, eyelashes, lacrimal apparatus and the conjunctiva

Question 2

What is the protective bony cavity that holds the eyeball?

Answer 2

the orbit

Question 3

What are the three pairs of major eye muscles?

Answer 3

the superior and inferior obliques, the superior and inferior rectus muscles, and the lateral and medial rectus muscles

Question 4

What is binocular vision?

Answer 4

it occurs when the muscles of both eyes work together to make normal depth perception possible

Question 5

How is the eyeball protected from foreign matter?

Answer 5

the eyeball is protected with the combination of the upper and lower eyelid, the eyebrow and the eyelashes

Question 6

What is the conjunctiva and where is it located?

Answer 6

it is a clear, thin mucous membrane that covers the inner surface of the eyelids and the back and sides of the eye’s outer surface

Question 7

What are the primary functions of the conjunctiva?

Answer 7

keep the front surface of the eye and inner surface of the eyelid lubriacted, and protect the eye from dust and debris as well as infection-causing microorganisms

Question 8

What are the three layers of eyeball wall?

Answer 8

the sclera, choroid, and retina

Question 9

What is the sclera’s role in the eyeball?

Answer 9

it is the tough outer tissue that protects the entire eyeball and is also known as the white of the eyeball

Question 10

What is the role of the choroid in the eyeball wall?

Answer 10

it is the middle layer of the eye that contains the blood vessels that nourish the eye

Question 11

What is the role of the retina in the eye?

Answer 11

it is the innermost layer that lines the back of the eye, it converts light into electrical impulses that travel through the optic nerve to the brain which interprets them as images

Question 12

The interior of the eyeball has how many segments?

Answer 12

two segments; anterior and posterior. The anterior segment is divided into the anterior and posterior chamber

Question 13

Where are the anterior and posterior chambers in the eyeball?

Answer 13

the anterior chamber is between the cornea and the lens, the posterior chamber is between the iris and the lens

Question 14

What fluid fills the chambers of the anterior segment?

Answer 14

aqueous humor

Question 15

What fluid fills the space behind the lens in the eyeball?

Answer 15

vitreous humor

Question 16

What is the cornea and how does it help the eye?

Answer 16

it is a transparent, dome shaped membrane at the center of the front of the eye, it helps focus light that comes into the eye on the retina abd also screens out UV light from the sun to prevent injury to the eye

Question 17

What is the iris and what is its primary job?

Answer 17

the iris is the colored portion of the eye, it regulates how much or how little light enters the eye by muscles within the iris

Question 18

What is the pupil and what does it do?

Answer 18

the pupil is the black opening in the center of the iris where light enters the eye, it works in conjunction with the iris to allow light in

Question 19

What is the lens and what is its role in the eye?

Answer 19

the lens is the clear part of the eye behind the iris that helps focus light on to the retina, it also adjusts the eye’s focus so we can see things closely and farther away

Question 20

True or false?

The lens is the black opening in the center of the iris

Answer 20

false, that is the pupil

Question 21

True or false?

The retina is light-sensitive tissue that lines the back of the eye

Answer 21

true

Question 22

True or false?

The cornea is the primary structure focusing light rays entering the eye

Answer 22

true

Question 23

True or false?

The role of the aqueous humor is to constrict or enlarge the pupil

Answer 23

false, that is the role of the iris

Question 24

True or false?

The conjunctiva is a mucous membrane

Answer 24

true

Question 25

True or false?

The sclera provides the blood supply for the entire eye

Answer 25

false, that is the role of the choroid