Ch 16 Special Senses - Hearing, Taste, Vision

Question 1

taste chemoreceptors

Answer 1

chemicals dissolved in saliva

Question 2

smell chemo receptors

Answer 2

chemicals dissolved in nasal fluids

Question 3

taste buds

Answer 3

gustatory receptors

Question 4

VII facial nerve

Answer 4

innervates anterior 2/3 of tongue

Question 5

IX glossopharyngeal nerve

Answer 5

innervates posterior 1/3 of tongue

Question 6

X vagus nerve

Answer 6

innervates oropharynx

Question 7

what kind of receptors does the mouth contain

Answer 7

mechanoreceptors, thermoreciptors, and nociceptors

Question 8

roof of nasal cavity contains this type of tissue

Answer 8

olfactory epithelium

Question 9

how many different smells can humans distinguish

Answer 9

10000 odors from 100 receptors

Question 10

olfactory receptor cells

Answer 10

filaments of olfactory nerve, synapse with olfactory bulb

Question 11

accessory eye structures

Answer 11

eyebrows, eyelids, eyelashes, conjuctiva, lacrimal structures, extrinsic eye muscles

Question 12

sclera

Answer 12

protects and shapes eye, provides anchor for eye muscles

Question 13

cornea

Answer 13

anterior, clear; lets light in and bends light as it enters eye. many nerve endings, no blood or immune supply

Question 14

outer layer of eye

Answer 14

sclera, cornea

Question 15

middle layer of eye

Answer 15

choroid, ciliary body, iris, pupil

Question 16

choroid

Answer 16

blood rich, brown appearance

Question 17

ciliary body

Answer 17

smooth muscle surrounding lens, suspensory ligaments

Question 18

iris

Answer 18

visible colored part, only brown pigments

Question 19

pupil

Answer 19

allow light to enter eye

Question 20

inner layer

Answer 20

retina, optic disc, macula lutea/fovea centralis

Question 21

retina

Answer 21

contains photoreceptors rods and cones
rods - dim light and peripheral vision; black and white fuzzy images
cones - bright light and high acuity; color, sharp images

Question 22

optic disc

Answer 22

where optic nerve exits eye
blind and weak spot - sclera can’t cover

Question 23

macula lutea/fovea centralis

Answer 23

where lights hit eye most directly, most cones concentrated

Question 24

lens

Answer 24

biconvex, clear, flexible, avascular

Question 25

cataracts

Answer 25

clouding of lens, mostly from age, hardening and thickening of lens

Question 26

internal chambers

Answer 26

anterior segment, posterior segment

Question 27

anterior segment

Answer 27

holds aqueous humor, behind cornea in front of lens, aqueous humor regenerates and circulates

Question 28

posterior segment

Answer 28

holds vitreous humor, behind lens, formed in embryo and lasts lifetime

Question 29

glaucoma

Answer 29

aqueous humor drainage is blocked, pressure inside eye builds up, retina and optic nerve compressed, results in blindness unless detected early

Question 30

astigmatism

Answer 30

unequal curves on lens or cornea, blurry images

Question 31

light hits rods

Answer 31

low light excitation, crude visual perception, convergent pathways

Question 32

light hits cones

Answer 32

high light excitation, high definition color vision, similar pigments as rods

Question 33

what kind of potentials do photoreceptors generate

Answer 33

graded potentials

Question 34

what kind of potentials do ganglion cells generate

Answer 34

action potentials

Question 35

opsins

Answer 35

four versions of opsins w sensitivity to wave lengths of light

Question 36

rhodopsin

Answer 36

purple light, highly sensitive to light found in rod cells

Question 37

where are cones found

Answer 37

highly concentrated at the fovea and more dispersed around the retina

Question 38

how much of the retina does the fovea make up

Answer 38

1% however over 50% of visual cortex is dedicated to interpreting sensations from this area