Chapter 13 Concepts

Question 1

The eyeball transmits an external image to the brain via the ______ ______

Answer 1

optic nerve

Question 2

What are the three layers of the eyeball

Answer 2

sclera, choroid, retina

Question 3

Lighter enters the eyes through structures of the

Answer 3

sclera

Question 4

light is focused onto the sensory receptor cells of the _____

Answer 4

retina

Question 5

What do sensory receptor cells do

Answer 5

convert light to electric signals that travel via the optic nerve

Question 6

What is the outermost layer of the eyeball

Answer 6

the sclera

Question 7

The sclera is the ____ part of the eye

Answer 7

white

Question 8

What is the anterior portion of the sclera

Answer 8

the cornea

Question 9

what does the cornea do

Answer 9

refract light rays as they pass through and enter the eye

Question 10

What is the middle layer of the eyeball

Answer 10

the choroid

Question 11

What does the choroid do for the eye

Answer 11

distribute blood supply

Question 12

What are the anterior parts of the choroid layer

Answer 12

iris, pupil, ciliary body

Question 13

What connects the lens to the ciliary body

Answer 13

suspensory ligaments

Question 14

What is the innermost layer of the eyeball

Answer 14

the retina

Question 15

what are the two types of sensory receptor cells

Answer 15

rods and cones

Question 16

what are rods responsible for

Answer 16

to be active in dim light and help the eye see gray tones

Question 17

what do cones do

Answer 17

are active in bright light and are responsible for color vision

Question 18

Light that passes through the lens strikes the ____ _____

Answer 18

macula lutea

Question 19

What is the name for the depression on the macula lutea

Answer 19

fovea centralis

Question 20

What does the fovea centralis contain

Answer 20

cones

Question 21

what is the optic disk

Answer 21

spot where optic nerve leaves the eyeball, spot where retinal blood vessels enter and leave

Question 22

True or false: the optic disk contains no rods or cones

Answer 22

true

Question 23

the optic disk is also referred to as the ____ ____ in each eye

Answer 23

blind spot

Question 24

What is the watery fluid that fills the spaces between the cornea and lens

Answer 24

aqueous humor

Question 25

what is the semisolid gel that fills the large open area between the lens and retina

Answer 25

vitreous humor

Question 26

How many muscle control the eye

Answer 26

6; four rectus, two oblique

Question 27

Rectus muscles produce movement in a ___ ____

Answer 27

straight line

Question 28

Oblique muscles produce ______ eye movement

Answer 28

diagonal

Question 29

what can weakness in the external eye muscles cause

Answer 29

strabismus

Question 30

What is the conjunctiva

Answer 30

a mucous membrane lining that provides protection by sealing off the eyeball in the socket

Question 31

What are the structure apart of the lacrimal apparatus

Answer 31

lacrimal gland, lacrimal canals, nasolacrimal duct

Question 32

What does the lacrimal gland do

Answer 32

produce tears to wash and lubricate the eye

Question 33

what do the lacrimal canals do

Answer 33

drain tears into the nasolacrimal duct

Question 34

what does the nasolacrimal duct do

Answer 34

carries the drainage to the nasal cavity

Question 35

What is the order of light when it enters the eye

Answer 35

cornea --> pupil --> aqueous humor --> lens --> vitreous humor --> retina (rods and cones) --> optic nerve --> brain

Question 36

What are the proper functions of the four mechanisms

Answer 36

external eye muscles coordinated, pupil admits correct amount of light, lens focus light onto retina, optic nerve transmits the sensory images to the brain

Question 37

What is the ear responsible for

Answer 37

hearing, equilibrium

Question 38

sensory information is carried from the ear to the brain by the _______ ______

Answer 38

vestibulocochlear nerve

Question 39

what portions carries hearing information

Answer 39

cochlear

Question 40

what portion carrier equilibrium information

Answer 40

vestibular

Question 41

what does the external ear consist of

Answer 41

auricle, auditory canal, tympanic membrane

Question 42

what does the auricle do?

Answer 42

functions like a funnel by capturing sound waves

Question 43

what are the names of the ossicles

Answer 43

malleus, incus, stapes

Question 44

What does the eustachian tube do

Answer 44

connect the nasopharynx and the middle ear, equalize pressure

Question 45

what is the name of the fluid filled cavity in the inner ear

Answer 45

the labyrinth

Question 46

what are the structures of the inner ear

Answer 46

vestibule, cochlea, semicircular canals, utricle, saccule

Question 47

what are the hair cells within the cochlea called

Answer 47

the organ of Corti

Question 48

what are the steps to hearing

Answer 48

- sound travels down the external auditory canal and strikes the tympanic membrane - tympanic membrane vibrates the ossicles - ossicles create vibrations across the middle ear to the oval window - oval window vibrates the fluid in the cochlea - fluid vibrations strike hair cells and stimulate nerve endings - nerve endings send impulses to the brain