Special Senses - vision

Question 1

the RECEPTORS of special senses are LOCALIZED IN

Answer 1

SPECIFIC AREAS of the head, as opposed to the more widely distributed receptors associated with most general senses such as touch and pain

Question 2

the NEURAL PATHWAYS for specialized sense tend to be more

Answer 2

COMPLEX than those for general sense

Question 3

RECEPTORS for vision are located in _____ _____ of the eye and are specialized cells known as ____ and _____

Answer 3

THE RETINA;

RODS AND CONES

Question 4

EYELIDS

Answer 4

protects the eyes from foreign objects and excessive light

shade the eyes during sleep

spread lubricants over surface of eyeball

Question 5

CONJUCTIVA

Answer 5

a thin mucous membrane that lines the underside of the eyelids and the exposed portion of the sclera but not the cornea

Question 6

EYELASHES AND EYEBROWS

Answer 6

protect the eyeballs from foreign objects, perspiration and excessive light

Question 7

LACRIMAL GLANDS

Answer 7

produce tears and are located superior to the upper eyelids

Question 8

3 primary layers or tunics of the eye

Answer 8

outer fibrous tunic

middle vascular tunic

inner tunic

Question 9

OUTER FIBROUS TUNIC

Answer 9

consists of the anterior CORNEA and the posterior SCLERA

Question 10

MIDDLE VASCULAR TUNIC

Answer 10

consists of THE IRIS, CILIARY BODY, and the CHOROID

Question 11

INNTER TUNIC

Answer 11

consists of the RETINA, which contains the receptors for vision

Question 12

CORNEA

Answer 12

TRANSPARENT and covers the deeper iris

its curvature helps to focus light rays on the retina

Question 13

SCLERA

Answer 13

the WHITE of the eye and gives shape to the eyeball

protects inner structures

serves as an attachment site for extrinsic eye muscles

Question 14

CHOROID

Answer 14

lines most of the internal surface of the sclera

VERY VASCULAR and supplies nutrients to the retina

Question 15

CILIARY BODY

Answer 15

consists of ciliary processes and ciliary muscle

Question 16

contraction of the ciliary muscles does what

Answer 16

ALTERS THE SHAPE OF THE LENS, accommodating for near or far vision

Question 17

IRIS

Answer 17

the COLORED PORTION OF THE EYE

suspended between the cornea and lens by ciliary processes

Question 18

SMOOTH MUSCLE FIBERS OF THE IRIS run in……directions.

contraction of these muscle fibers change the…

Answer 18

radial and circular

SIZE OF THE PUPIL

Question 19

changing the size of the pupil varies the amount of….

Answer 19

light that enters the eye, like the shutter of a camera

Question 20

rods and cones are located in the ____ ____ of the retina

Answer 20

photoreceptor layer (rods and cones are photoreceptors)

Question 21

Rods

Answer 21

very sensitive to light

FUNCTION IN LOW LIGHT LEVELS

provide vision of LOW ACUITY (detail) and no color

Question 22

CONES

Answer 22

less sensitive to light

ONLY FUNCTION IN BRIGHT LIGHT

provide vision of HIGH ACUITY as well as COLOR

Question 23

THE ANTERIOR CAVITY

Answer 23

anterior to the lens and consists of two chambers

both chambers are filled with AQUEOUS HUMOR that nourishes the cornea and the lens

Question 24

the two chambers of the ANTERIOR CAVITY are

Answer 24

anterior chamber - between the cornea and the iris

posterior chamber - behind the iris and in front of the lens

Question 25

the VITREOUS CHAMBER

Answer 25

posterior to the lens and is filled with a gel-like substance that prevents collapse of the eyeball and keeps the retina flat

Question 26

REFRACTION

Answer 26

the bending of light rays as they pass through mediums of different densities

Question 27

ACCOMMODATION

Answer 27

accommodating our vision to focus on things either near or far distant objects enter as parallel rays close objects enter as divergent rays

Question 28

CONSTRICTION

Answer 28

by contracting and relaxing the smooth muscle fibers of the iris, we allow light rays to only enter through the center of the pupil

Question 29

The outer segments of cones and rods are

Answer 29

CONSTANTLY RENEWED

Question 30

PHOTOPIGMENTS in the outer segments of cones and rods are

Answer 30

colored proteins that undergo structural changes when they absorb light

Question 31

photopigments contain

Answer 31

a derivative of VITAMIN A called retinal and a glycoprotein known as opsin

Question 32

RETINAL

Answer 32

the light-absorbing portion of photopigments

Question 33

the axons of ganglion cells exit the eyeball as the

Answer 33

OPTIC NERVE (CN II)

Question 34

the way that axons of the optic nerve pass through the optic chasm allows

Answer 34

INFORMATION FROM EACH EYE TO REACH BOTH THE LEFT AND RIGHT SIDES OF THE BRAIN

Question 35

THE PRIMARY VISUAL AREAS of the brain

Answer 35

the OCCIPITAL LOBE OF THE CEREBRAL CORTEX