Physiology Test 5

Front 1

the function of the sensory system is to interface between __ and __ and the __

Back 1

internal and external enviornment and the nervous system.

Front 2

the physiological capacity to precieve data for perception.

Back 2

sense

Front 3

explain the basic function of the sensory system

Back 3

sense enviornment, encode features, transmits information to CNS for decoding and use

Front 4

what three tings does the sensory system need to determine?

Back 4

what is present: modality and submodality coding

how much is present: intensity coding

Where it lies: location coding

Front 5

explain the basic organization of teh sensory sytem

Back 5

stimulus is required

goes to the filter, filter limits stimulus and modides stimulus parameter so it can be taken to the tranducer

traducer converts signals to receptor potentials, transports to encoder

the encoder converts the receptor potential into frequency code

frequency code translated to membrane potential which causes an action potential

action potential is conveyed to effector systems

effectors cause a response

Front 6

the first functional element of the sensory receptor, usually non-neuoral tissue. allows only a portion of the stimulus to be conveyed to teh transducer.

Back 6

filter

Front 7

conditions the stimulus making the receptor function with relative specificity for one modality

Back 7

filter

Front 8

the filter is usually __ tissue

Back 8

non neural

Front 9

what are the two roles of teh filter?

Back 9

limit access, change stimulus parameters

Front 10

converst stimulus energy into a change in voltage across teh membrane of teh sensory receptor with a minimal loss of information

Back 10

tranducer

Front 11

the transducer creates the __

Back 11

receptor potential

Front 12

explain how the transducer generates a receptor potential

Back 12

change in membrane permiability of Na and K ions.

Front 13

do receptor membranes respond to electrical stimulation?

Back 13

NO.

Front 14

receptor potentials are __

Back 14

graded (they increase in magnitude as a stimulus gets stronger)

Front 15

the receptor potential does not __

Back 15

propagate (it only travels a short distance)

Front 16

an increase in teh strength of stimulus causes a __ in teh amplitude of a receptor potential

Back 16

increase

Front 17

what happens to the receptor stimuls amplitude after stimulus strength increases a long time?

Back 17

it levels off (becomes saturated)

Front 18

converts the magnitude of a receptor potential into a frequency code that is carried by action potentials down an axon

Back 18

encoder

Front 19

the __ is teh location of teh voltage gated Na and K channels capable of producing action potentials

Back 19

encoder

Front 20

if the receptor potential entering the trigger zone is __, an action potential is generated.

Back 20

above threshold

Front 21

the larger the receptor potential, the __ teh frequency of action potentials

Back 21

higher

Front 22

using the example of a pacinian corpuscle, what is the filter, tranducer, and encoder?

Back 22

filter: connective tissue capsule

transducer: unmyelinated free nerve ending

ecoder: trigger zone (1st node of ranvier)

Front 23

as long as a stimulus is above threshold, a receptor potential will __

Back 23

be generated

Front 24

is a receptor potential generated if force is applied to an area other than the free nerve ending?

Back 24

no

Front 25

what are 6 kinds of sensory receptors?

Back 25

mechano, thermo, chemo, osmo, photo, and nocio receptors

Front 26

what are poly modal receptors?

Back 26

respond to 2 or more forms of stimlui

Front 27

what three things can poly-modal receptors be divided into?

Back 27

specialized receptor cells, specialized endings on nerve fibers, free nerve endings

Front 28

kind of poly modal receptor:

most sensitive types

example: photo receptor

Back 28

specialized receptor cells

Front 29

an example of a specialized ending on nerve fibers is the __

Back 29

pacinian corpuscle

Front 30

kind of polymodal cells, have no anatomical specialization at teh receptor site. encompase the full range of sensory modalities and are the most common receptor type.

Example: pain receptor

Back 30

free nerve endings

Front 31

sensory receptors are connected to __

Back 31

sensory units

Front 32

all terminals of any one sensory unit have the same kind of __

Back 32

receptor

Front 33

the fraction of the total energy of a particular modality that intitiates a response in a sensory receptor or sensory unit

Back 33

receptive field

Front 34

the sensory unit with the greatest number of sensory receptors has the __

Back 34

largest receptive field

Front 35

all sensory receptors have

A: filters

B: transducers

C: coders

D: all of the above

Back 35

D

Front 36

what are teh five attributes of sensory coding?

Back 36

modality, location, intensity, temporal, affect

Front 37

the part of coding that tells you what is present (quality)

Back 37

modality, submodality

Front 38

vison, hearing, taste, smell, and somesthesis are all examples of __, where as color/black and white vision, ptich, sweet, sour, salty, umami, pugent, musky, floral, putrid, pressure, vibration, temp and touch are examples of __

Back 38

modality, submodality

Front 39

modality coding is done by __

Back 39

labeled lines

Front 40

an anatomical grouping of receptors and pathways devoted to a particular modlaity

Back 40

labeled lines

Front 41

submodality coding is done by __

Back 41

pattern codes

Front 42

the pattern of activity within teh system of labeled lines

Back 42

pattern codes

Front 43

__ coding is accomplished by an anatomical sorting of organization of the pathways and their central projections

Back 43

location

Front 44

where is location coding particularly well developed?

Back 44

where the receptors lie in "sheets" ie skin

Front 45

what is an example of location coding in teh body

Back 45

the homunculus

Front 46

done by teh total number of impulses per second coming from teh receptor population

Back 46

intensity

Front 47

what are the 5 basic mechanisms of intensity coding?

Back 47

rate, recruitment, adaptation, threshold, saturation

Front 48

the frequency (number per second) of action potnetials int eh individual sensory units. teh stronger the stimulus, the more actin potentials are sent up teh affrent fibers of the sensory unit

Back 48

rate

Front 49

the number of units that get activated by teh stimlus. increases with intesnity of teh stimulus

Back 49

recreitment

Front 50

the stronger the threshold, the greater the __

Back 50

recruitment

Front 51

a measure of how well a sensory receptor maintians its response to a constant stimlus

Back 51

adaptation

Front 52

in terms of adaptation, slowy adapting sensory receptors keep producing membrane potnetials as long as teh __

Back 52

stimulus is applied

Front 53

rapidly adapting sensory receptors __ producing membrane potnetials even when teh stimlus is still present

Back 53

stop

Front 54

the minimum value of intensity to trigger an action potential

Back 54

threshold

Front 55

states that as intensity increases, eventually teh nerve fiber reaches its upper limit for carrying impulses. further increases in stimulus do not produce a corresponding increase in response

Back 55

saturation

Front 56

when different patterns of firing may provide information about submodality. a resonse is dependent on the rate of change of stimlus application whithin a particular frequency rance. most receptors don't respond to constant stimlui but are sensitive to stimlus change

Back 56

temporal coding

Front 57

how many of the following are true abou receptor potentials:

a: receptor membranes respond to electical stimulation as well as specific sensory stimulation

b: receptor potentials travel short distances and do not propagate

c: receptor potentials are generated by the encoder of a sensory receptor

d: receptor potentials are teh same as AP's

e: receptors fire at a greater rate when a stimlus becomes stronger

Back 57

B, E

Front 58

the least measurabel criterion. this attribute takes into account emotional content (like pain) and learnig and membory which depends on prior input

Back 58

affect coding

Front 59

which sensory receptor generates AP and sends informatoin to teh braine?

A: filter

B: transducer

C: encoder

D: all the above

Back 59

C

Front 60

what are the sub modalities and sub sub modalities of touch?

Back 60

SM: itch/tickle (crude touch), discriminative touch

SSM: pressure, flutter, vibration

Front 61

what are the sub modalities of temp?

Back 61

warm/hot, cool/cold

Front 62

what are the sub modalities of pain?

Back 62

sharp cutting, dull burning, deep aching

Front 63

what are the sub and sub sub modalities of proprioception?

Back 63

SM: position: static forces, movement: dynamic forces

SSM: muscle length, tension, joint pressure, angle

Front 64

largest diameter, myelinated axons, fastest conducting. usually proprioceptors of skeletal muscle

Back 64

a alpha

Front 65

medium sized, myelinated fibers, fast speed, mechanoreceptors of skin (encapsulated fibers)

Back 65

A beta

Front 66

thinly myelinated, carrying signals about sharp pain and cold temp

Back 66

alpha delta

Front 67

small, unmyelinated fiber, relays information about dull pain and hot temp

Back 67

C

Front 68

what are the two sensory pathways of somatic sensation

Back 68

DCML and spinothalmic

Front 69

most sensory receptors of the skin

Back 69

mechanoreceptors

Front 70

sensory receptors that are sensitive to physical distortion like bending or stretching

Back 70

mechanoreceptors

Front 71

what are 5 kinds of mechanoreceptors

Back 71

hair receptor, pacinian corpuscle, ruffini endings, meissner corpuscle, merkel disk receptor

Front 72

only sensory recepotr cell type in teh somatosensory system

Back 72

merkel disk receptor

Front 73

the receptor fields of pacinian corpuscles are __ while those of meissners coropuscles are __

Back 73

large, small

Front 74

a small surface area means a more __

Back 74

refined sense

Front 75

a large density of sensory receptors mean more __

Back 75

refined touch

Front 76

__ mechanoreceptors respond quickly at first, then stop firing even though teh stimulus continues. best suited to represent time varying (vibrating or moving) stimuli

Back 76

rapidly adapting

Front 77

__ fibers are god for rapidly adapting fibers

Back 77

A alphas

Front 78

__ mechanoreceptors generate a more sustained response during a long stimulus. best suited to represent static stimuli

Back 78

slowly adapting

Front 79

pacinian corpuscles are __

Back 79

rapidly adapting

Front 80

__ are sensitive to vibrating, hgih frequency stimuli, and almost unresponsive to steady pressure

Back 80

pacinian corpuscle

Front 81

meissner corpuscels are __ type mechanorecepotrs, sense __ and adapt __

Back 81

encapsualted and layered, touch: flutter and movement, rapid

Front 82

pacinian corpuscles are __ type mechanorecepotrs, sense __ and adapt __

Back 82

encapsulated, layerd, touch: vibration, rapid

Front 83

ruffini are __ type mechanorecepotrs, sense __ and adapt __

Back 83

encapuslated collagen, touch: movement, rapid

Front 84

hair follicles are __ type mechanorecepotrs, sense __ and adapt __

Back 84

unencapsulated, touch: movement, rapid

Front 85

merkel complex cells are __ type mechanorecepotrs, sense __ and adapt __

Back 85

specialized epithelial cell, touch, pressure, form, slow

Front 86

free nerve endings are __ type mechanorecepotrs, sense __ and adapt __

Back 86

unencapsulated, pain,touch, temp, depends

Front 87

sense outside temperature and maintains body temp

Back 87

thermoreceptors

Front 88

warm receptors begin firing aove __ and stop firing above __

Back 88

30 C and 45 C

Front 89

cold receptor fire __ over a braod range of skin temperatures from about __ to __

Back 89

faster, 30 C-10 C

Front 90

at approximately 33 C once cannot tell if the temperatuer is cold or warm b/c __

Back 90

both cold and warm receptors are activated equally

Front 91

at around __, one may sense cold even though the temp is high b/c cold receptors are activated more than warm receptors

Back 91

50 C

Front 92

__ fire faster during reductions in temp

Back 92

cold receptors

Front 93

__ fire faster during increases in temp

Back 93

warm receptors

Front 94

why is pain good?

Back 94

there are physical stimului that in excess are harmful to the body

Front 95

the protective mechanism for the obdy occurs in response to __ and casues the indivudal to reacto to __

Back 95

tissue damage, remove stimulus

Front 96

free, branching, unmyelinated nerve endings that signal that the body tissue is being damaged or is at risk of being damaged

Back 96

nocioceptors

Front 97

respond to intense mechanical stimulation (pinching, cutting stretching)

Back 97

mechanociceptors

Front 98

respond to burng heat (>45 C tissue proteins become denatured and damage occurs) or extreme cold

Back 98

termal nociceptors

Front 99

respond to a variety of agents from the enviornment or from the tissue itself.

examples: K, extremes of pH, neuroactive substances ie histamines and bradykinin, various irritants

Back 99

chemically sensitive, mechanically insensitive

Front 100

respond to high intesnity stimuli that are combinations of mechanical, thermal, and chemical stimuli.

Back 100

polymodal

Front 101

there pain receptors are present in most body tissues except the brain

Back 101

polymodal

Front 102

what are 7 characteristics of slow pain?

Back 102

burning or soreness

transmitted by C fibers

poorly localized

all internal localized (except the brian)

pain radiates or is referred

diffuse, slower onset, longer duration

examples: labor pain, chemical burn

Front 103

what are 7 characteristics of fast pain?

Back 103

pricking pain

trasmited by A delta fibers

well localized

mainly on skin, mouth, and anus

pain doesnt radiate

short duration

example: pain from a surgical incision

Front 104

pain referred from the area of damage to another area

example: kidney pain may feel like lower back pain

Back 104

referred pain

Front 105

pain of a missing limb

Back 105

phantom pain

Front 106

caused by alcohol (oxicity of alcohol itself irritates the meninges,

constipatoin (form absorbed toxic products or changes in circulatory system resulting from loss of fluid in the gut

Back 106

intracranial pain

Front 107

what are three examples of extracranial headaches?

Back 107

mucscle spasm

sinus headache

eye disorders

Front 108

extracranial headache caused by emotion/tension causing muscles of the head to become spasic, pain is referred to overlying areas of the head

Back 108

muscle spasm

Front 109

extracranial headache caused by pain from mucous membranes of nose and nasal sinuses, pain is referred behind the eyes or forehead or face

Back 109

sinus headache

Front 110

extracranial headache where difficulty focusing stresses the ciliary muscles and can cause spasm in facial and extraocular muscles. excessive irradiation by light rays causes irritation of teh membranes around teh eye

Back 110

eye disorders

Front 111

globulin and protein kinases, arachidonic acid, histamine, nerve growth factor, susbstace P, K, seotonin, ACh, low pH, ATP, and muscle spasm/lactic acid cause __

Back 111

activation of nocioceptors

Front 112

explain the gate theory of pain

Back 112

pain can be modified by nonpainful sensory input

pain from nociceptors (A delta and C fibers) can be reduced by simultaneous activity in low threshold mechanoreceptor (A alpha and A beta fibers)

explain why it feels good to rub the skin around your shin when you bruise it

Front 113

taste and smell include __

Back 113

positive and negative chemostaxis

Front 114

__ in taste and smell is sued to find nurients or locate a mate

Back 114

postive chemotaxis

Front 115

__ in taste and smell helps us avoid noxious agents like rotten smells and food

Back 115

negative chemotaxis

Front 116

the nervous system codes for chemicals in our enviornment by using mixture of __ and __ coding

Back 116

labeled line, populatino

Front 117

where each chemical stimulus which has its own receptor and cirucit

Back 117

labled line coding

Front 118

where receptors and ciruits are not ultimately selective. instead the nervous system analyzes all of the chemical responses coing in and compares them in order to pinpoint what the chemical stimulus might be

Back 118

populatoin coding

Front 119

there are about __ taste buds in teh walls of papilae

Back 119

10,000

Front 120

what are the 3 kinds of papillae and where are they located?

Back 120

circumvailate (post 1/3 of tongue)

foliate (post and lat surfaceof tongue

fingiform (top and sides of tongue)

Front 121

where does the watery fluid that moistens the tongue come from?f

Back 121

serous glands

Front 122

what are the three kinds of taste cells?

Back 122

receptor cells

supporting cells

basal cells

Front 123

taste cell that is a modified epithelial cells, 50-150 per taste but

Back 123

receptor cell

Front 124

type of taste cell that develops into receptor cells to replace cells that are turned over

Back 124

supporting cells

Front 125

type of taste cells that develops itno supporting cells

Back 125

basal cells

Front 126

how many weeks are receptor taste cells turned over?

Back 126

1-2 weeks (basal--supporting--recepotr cells)

Front 127

afferent nerves for taste enter on teh __ and end on teh __

Back 127

buds, recepotr cells

Front 128

on afferent taste nerve may innervate several __

Back 128

recptors

Front 129

taste buds are innervated by CN __, __, and __

Back 129

VII, IX, X

Front 130

explain the pathway of the taste system

Back 130

1st synapse: taste bud

2nd synapse: in medulla

3rd synapse: in thalamus

signal ends in teh primary gustatory cortex

Front 131

why makes the gustatory system distinctive?

Back 131

most of its fibers are uncrossed

Front 132

one recepotr cell can have more than one __ but has a __ at threshold levels

Back 132

basic category of taste, preferred taste

Front 133

the frequency of AP in taste neurons __ with quantity of taste molecules

Back 133

increases

Front 134

what are the 5 types of taste sensations

Back 134

salty, sour, bitter, sweet, umami

Front 135

the greater the amount of tastant, the __ teh firing rate of afferent fibers

Back 135

faster

Front 136

each taste cells resopnds different to __

Back 136

four tastants

Front 137

how does populatoin coding of taste occur?

Back 137

responses of 4 taste cells to four different tastants are combined in teh brain to determine the final taste

Front 138

how does taste transduction occur?

Back 138

particles attach to receptors to stimulate 2nd messengers.

ionic stimuli go through tehion channel

Ca is released into cell which triggers release of NT substance

Front 139

teh salt recepotrs use a __ channel

Back 139

ENAC

Front 140

what sensory modalities are used in taste perception? (5)

Back 140

taste, tactile, visual, auditory, olfactory

Front 141

a combination of smel, taste, spiciness, pain, temperature, sound, and texture

Back 141

flavor

Front 142

eating chocolate swirl ice cream will __

Back 142

stimulate a taste bud sensitive to several tastants if the stimulus is strong enough

Front 143

taste is influenced by __, __, and __

Back 143

adaptation, memory, conditioning

Front 144

taste is __, there are cultural differences in taste prefrences

Back 144

aquired

Front 145

humans can detect teh presence of as few as __ molecules of an odorant in the room

Back 145

10^8

Front 146

at low concentractions of an odor, the smell of sensations is __

Back 146

unspecifc

Front 147

at high concentractions of an odor, a specific odor is __

Back 147

identified

Front 148

__ chemical elements play a role in odor sensation, only __ and __ are odorus as elements

Back 148

16, ozone, halogens

Front 149

the sense of smell is carried by __ in teh olfacotry epithelium, lying deep within teh nasal cavity just below the cribiform plate

Back 149

olfactory receptors

Front 150

__ are the primary afferent neuron. they are both the transducer and encoder of the signal

Back 150

olfacotyr recepotrs

Front 151

chemosensory transduction for olfaction occurs in teh __

Back 151

mucus lining the surfaec

Front 152

olfactory recepotrs have very __ action potentials

Back 152

slow

Front 153

what are the only neurons that undergo constant renewal

Back 153

olfactory neurons

Front 154

there is a rapid turnover every __ weeks basal cells to receptor cells in olfactory neurons

Back 154

4-8

Front 155

cells that produce mucus which is replaced every 10 min so odorants dissolve in teh mucus before reaching olfacotry recepotr cells. is water based.

Back 155

supporting cells

Front 156

neurons and supporting cells share __. these seal teh neuroepithelium against penetration of substances through the surface

Back 156

tight junctions

Front 157

the __ in teh mucus from teh nasal supporting cells contribute to odorant concentration or removal

Back 157

odorant binding proteins

Front 158

these cells become olfactory receptor cells

Back 158

basal cells

Front 159

explain olfactory transduction (7)

Back 159

odorant is absorbed into mucus layer

binds to receptor sites

stimulates G protein

Stimulates AC, forms cAMP, binds to specifc cation channel

membrane depolarizes generating a receptor potential

RP graded depending on concentration

transduction ends

Front 160

what are three ways in which olfactory transduction ends?

Back 160

odorants diffuse

scavenger enzymes in mucus break down odorants

cAMP in recptor cell activates other pathways that end transduction process

Front 161

when the R hand is submersed in hot water and the L hand is not, what happens when both hands are submersed in cold water?

A: R senses that cold water is hotter than L

B: L hand senses that cold water is hotter than R hand

C: both hands sense temp of teh cold water similaryly

D: R hand senses that cold water is colder tha L hand

E: R hand sufferes from frost bite

Back 161

D

Front 162

each olfactory receptor is sensitive to a _

Back 162

wide variety of chemicals

Front 163

a mucus covering the cilia of an olfacotyr receptor cells:

A: is a thick gelatinous materal that is replaced one a month

B: is produced by gustatory receptor cells

C: prevents odorants from reaching olfactory receptor cells

D: is a filter of teh olfactory epithelium

Back 163

D

Front 164

the __ focuses the light onto the retina

Back 164

cornea

Front 165

the cornea and sclera make a border called the __

Back 165

limbus

Front 166

the cilliary body is composed of __, __, and a __

Back 166

cilliary muscles, projections, double membrane epithelial layer

Front 167

why is the epithelial layer of teh cilliary body important?

Back 167

it secretes aqueous humor

Front 168

the __ dictates how much light passes through teh lens

Back 168

iris

Front 169

imaginary axis where light passes through teh lens

Back 169

optic axis

Front 170

is infected c pinkey

Back 170

conjunctiva

Front 171

teh outer protective layer of teh eye

Back 171

sclera

Front 172

the middle, most vascular layer of the eye, supplies nutrients and oxygen to the retina

Back 172

choroid

Front 173

helps maintain teh lens, connected by cilliary body and teh lens

Back 173

zonule fibers

Front 174

innermost layer, site where different types of photoreceptors like rods and cones are located. light is focused here and a stimulus passes to the neurons

Back 174

retina

Front 175

a small pit in teh retina, important b/c it is where precise pictures are stimulated. cone cells located here (the photo receptors for color and bright light)

Back 175

fovea

Front 176

cones are located in teh __

Back 176

fovea

Front 177

light has both properties of both __ and __

Back 177

wave, particles

Front 178

the distance between successive waves

Back 178

wavelength

Front 179

teh number of waves per second

Back 179

frequency

Front 180

teh difference between wave trough and peak

Back 180

amplitude

Front 181

teh higher the waverlength, teh __ the frequency, teh __ the energy

Back 181

lower, lower

Front 182

the lower teh wavelength, the __ the frequency, the __ the energy

Back 182

higher, higher

Front 183

what are two kinds of high frequncy, short wavelength, high energy wave?

Back 183

gamma radiation, Xrays

Front 184

what are two examples of radiation emitted at lower frequencies, longer wavelengths, and low energy?

Back 184

radar, radio waves

Front 185

provides protection, nutrients, antibacterials and helps refract light for the eye

Back 185

tear film

Front 186

explain teh three layers of the tear film

Back 186

posterior layer rich in glycoproteins: from conjunctival goblet cells

water middle layer: secreted by lacrimal tissues (provides nutrients, everyday recycling event)

anterior oily layer: produced by meibomian glands and teh glands in teh eyelids

Front 187

teh __ is the part of teh outer layer of the eye which also includs teh sclera

Back 187

cornea

Front 188

the __ and __ present a tough physical barrier to trauma and infection and protects the internal structure of teh eye

Back 188

cornea and sclera

Front 189

the refractive power of teh cornea depends on teh __.

Back 189

the slowing of light at the air cornea interface

Front 190

if air is replaced with something that passes light at about the same speed as teh eye, the refractive power of teh cornea will be __

Back 190

eliminated

Front 191

the __ provides the most refractive power in teh eye. has a power of about 42 diopters.

Back 191

cornea

Front 192

what is the condition where teh flow of aqueous humor is blocked?

Back 192

glaucoma

Front 193

what are teh three functions of aqueous humor

Back 193

maintains a stable pressure, feeds avascular tissue, maintains clear vision

Front 194

what are the main regulators of aqueous humor flow?

Back 194

episcleral veins

Front 195

functions like a diaphragm in a camera to increase or decrease the amount of light entering the eye

Back 195

iris

Front 196

if the pupil is__, teh many rays are admitted, resulting in a sharp focus only for parallel rays with a certain focal length

Back 196

wide

Front 197

if teh pupil is __, tehn only a small number of parallel rays pass tough, resulting in a sharp focus at the focal plane and for a distance before and after the focal plane

Back 197

narrow

Front 198

explain how the F number affects the apeture and depth of field

Back 198

if something is farther away you need more stimulus so the apeture gets larger, F number gets smaller, and teh depth of field gets smaller

if something is close, you need less stimulus so the aperture gets smaller, teh F numer gets larger, and teh field of depth gets smaller

Front 199

teh __ is the imaginary line where light should travel directly when it enters the eye

the __ is the imaginary line where light should travel onces its been refracted by teh lens and cornea

the __ is the area in which light refraction occurs

Back 199

optic axis, visual axis, nodal point

Front 200

__ innervation controls pupil dilation

Back 200

sympathetic (NE)

Front 201

__ innervation controls pupil constirction

Back 201

parasympathetics (ACh)

Front 202

the function of the __ is to focus light on the retina

Back 202

lens

Front 203

the__ region of teh lense is wher teh cells differentiate

Back 203

bow

Front 204

which of teh following is true about aquesous humor?

A: it provides nutrients to teh lens and cornea

B: it is produced by teh iris and drains itno the viterous cavity

C: it is rich in protein making it a brown color

D: it removes waste products from the retina

Back 204

A

Front 205

the refractive power of the lens decrease with __

Back 205

age

Front 206

the lens is involved int eh formation of point images closer than about __ m

Back 206

9

Front 207

the process of teh lens focusing light on the retina

Back 207

accommodation

Front 208

what are the 6 steps of accommodation?

Back 208

ciliary muscles contract

suspensory lig attached to lens relaxes

the lens becomes more spherical due to its inherent elasticity

curvature of lens increases

refractive power of lens increases

object up close comes into focus

Front 209

what are two changes in eye seperate of teh lens that occur during accommodation?

Back 209

eyes converge, pupils constirct to increase field of depth

Front 210

when teh pupil is dilated, teh zonule fibers are __ and teh lens is __

Back 210

stretched, flat (non-accommodated)

Front 211

when teh pupil is small, the zonule fibers are __, and the lens is rounded

Back 211

relaxed, rounded (accommodate

Front 212

explain the 8 steps of the pupillary reflex

Back 212

optic nerve--optic chiasm--optic tract--projects to pretectum--preganglionic parasympathetics--CNIII--ciliary ganglion--smooth muscle of pupillary sphincter

Front 213

which is true for teh lense of teh eye in humans?

A: its a vacular and highly innervated sturcture

B: capsule of lens recieves nutrienst and maintains homeostasis

C: refractive power of the lens does not change throught life

D: bow region of lens is teh region of cell differentiation

Back 213

D

Front 214

what will present if the optic nerve is damaged on one side?

Back 214

the ipsilateral direct reflex is lost (when teh L eye is stimulated, neither pupil constricts, no signals reach brain from L eye due to damaged optic nerve)

the ipsilateral consensual reflex is intact (b/c light shone into R eye can signal to the brain, causes constirction of both pupils via teh normal oculomotor nerves)

the contralateral direct refelx is intact (b/c light shone itno the R eye can signal to the brain, causing constriction of both pupils via teh normal oculomotor nerves

the contralateral consensual refelx is los (b/c light shone into the eye on teh damaged side cannot signal to the brain; despite the R eyes motor pathway being intact, no signals from teh L eye are able to stimulate it due to the damge to the sensroy pathway of the L eye

Front 215

what presents with oculomotor nerve damage on one side?

Back 215

ipsilateral direct reflex is lost (when the L eye is stimulated, only teh R pupil constircts)

the ipsilateral consensual refelx is lost (when teh R eye is stimulated , only teh R pupil constircts)

the conralateral direct refelx is intact (b/c light shone into both eyes can still signal teh brain, the pupil on the undamaged side will still be able to constrict via its normal oculomotor n.

the contralateral consensual reflex is intact (b/c light shone into the L eye can still signal to the brain via the normal optic nerve, causing attempted constiction of both pupils; the contralateral puil consticts via its normal oculmotor nerve but the ipsilateral pupil is unable to constrict due to its damaged oculomotor nerve)

Front 216

when you begin reading your physiology notes after having watched a flock of birds fly overhead, what changes occur in you eyes allowing you to see your notes clearly?

A: the pupil size increases

B: zonule is stretched

C: curvature of lens decreases

D: cilliary muscle contracts

E: all of teh above

Back 216

D

Front 217

provides nutrients to cells, absorbs light not absorbed by rods and cones that could interupt normal signaling

Back 217

retinal pigment epithelium

Front 218

the part of teh retina which has teh photoreceptors (rods and cones) in it

Back 218

external limiting membrane

Front 219

the part of the retina that has teh upper portion of teh photoreceptors in it

Back 219

outer nuclear layer

Front 220

the are where rod and cone cells synapse with bipolar cells

Back 220

outer plexiform layer

Front 221

the area where bipolar nerves synapse with the ganglionic cells

Back 221

inner plexiform layer

Front 222

cells in the retina that are glial cells which function as support neurons

Back 222

muller

Front 223

what are the first order neurons in teh vision system?

Back 223

photoreceptors

Front 224

there are many __ rods than cones

Back 224

more

Front 225

in rodes the discs are __, in cones the discs are __

Back 225

free floating, connected

Front 226

both rods and cones produce graded __ potentials, only in response to retinal illumination

Back 226

hyperpolarizing

Front 227

the photorecepotr that is located in the entire retina except the fovea, help with peripheral vision, have low visual acuity, detect black and white color, have high sensitivty to light, have high convergence, have many cells, and use rhodopsin

Back 227

rods

Front 228

photoreceptors found mostly in the fovea, used in central vision, have a high visual acuity, see color, have a fast response time, have low sensitiviey to light, have relatively few cells, and use red, green, or blue opsin

Back 228

cones

Front 229

how does convergence differ in rods and cone?

Back 229

multiple rods can converge to one biopolar cells

each cone cell converges to one bipolar cell

Front 230

the __ occurs where there are no rods or cones

Back 230

blind spot

Front 231

explain darkness current

Back 231

in complete darkness, teh outer segment is depolarized.

there are high intracellular levels of cGMP, causes Na to come into the cells depolarizing the cell

Front 232

explain rod phototrandsuction in words

Back 232

light belaches rhodopsin, stimulates tranducin which activates PED which breaks down cGMP closing their ion channels thus hyperpolarizing the membrane

Front 233

how do rods depolarize (the retinoid cycle)

Back 233

retinal converts back to regular configuration (RPE)

transducin reassembles, GDP remains bound

PDE is inactivated

cGMP is created

Na channels re-open, depolarize the cell

Front 234

phototransduction in cones is the same as in rodes except for the type of __ in teh outer segments

Back 234

opsin

Front 235

blue cones contain blue opsin which are maximally activated by light with a wvelength of __

Back 235

420 nm

Front 236

green cones contain green opsin and are maximally activated a __ nm

Back 236

530

Front 237

red cones contain red opsin and are maximally activated at __ nm

Back 237

560

Front 238

states that preveived color is the relative actication of R, G, and B cones. the brain assigns colors based on a comparison of the information recieved from teh three cone types.

Back 238

young-helmholtz trichromacy theory of color detection

Front 239

__ occurs when one or more of the cone photopigment types is missing

Back 239

color blindness

Front 240

for the visual system, the 1st order neurons are the __, the 2nd order neurons are the __ and the 3rd order neurons are the __

Back 240

photoreceptors, bipolar cells, ganglion cells

Front 241

cells that generate axons that travel through teh optic nerve to the brain

Back 241

ganglioin cells

Front 242

ganglion cells are classified itno __ and __ cells types

Back 242

P type (small)

M type (large)

Front 243

ganglion cells that make up 10% of ganglion cells, have large receptive fields, have rapid action potentials, are more sensitive to low contrast stimuli, have transient burst of AP, and are insensitive to different wavelengths of light

Back 243

M type (rods)

Front 244

kind of ganlgion cells that are 90% of all ganglion cells, have small receptive fields, have slow AP, are less sensitive to low contrast stimuli, have sustained discharge, and are sensitive to different wavelengths

Back 244

P type (cones)

Front 245

the __ of teh ganglion cells is the area of the retina that when stimulated by light, changes the cells membrane potential

Back 245

receptive field

Front 246

ganglion cell receptive fields have __ organization

Back 246

central surround

Front 247

an __ ganglion cell responds with many AP when a dark spot (shadow) is imaged on its receptive field center. if the spot is enlarged to include the receptive field surround, the respnse is greatly __

Back 247

OFF-center, reduced

Front 248

ganglion cells are mainly responsive to differences in illumination that occur within their __

Back 248

receptive fields

Front 249

ganglion cell contrasts enhancement can cause a distoriton of the perception of __

Back 249

light and dark

Front 250

color is processed in __

Back 250

opponent pairs

Front 251

the presence of opponent color processing results in __

Back 251

after images

Front 252

what are three kinds of trichromats?

Back 252

normal (can distinguish about 150 hues)

protanomalous (reduced red sensitivity, distinguish only 5-25 hues)

deuteranolmalous (reduced green sensitiviey, can distingues 5-25 hues)

Front 253

what are three kinds of dichromates?

Back 253

protanopes: no red sensitiviey

deutranopes: no green sensitivity

tritanopes: insensitive to short wavelengths of light

Front 254

people who are totally color blind, world is seen as shades of gray

Back 254

monochromats

Front 255

the total amount of space that can be viewed by teh retina when teh eye is fixated straight ahead

Back 255

visual field

Front 256

teh ability of the eye to distinguish between two nearby points

Back 256

visual acuity

Front 257

acuity depends mainly on teh spacign of teh __ in teh retina

Back 257

photoreceptors

Front 258

the projection of the visual world into the retina

Back 258

visual field

Front 259

teh image of the target is __ on teh retina by teh lens system

Back 259

revesed

Front 260

the area that only the L eye can see

Back 260

Left monocular zone

Front 261

the entire area the L eye can see

Back 261

L visual hemifield

Front 262

the are that both eyes can see

Back 262

binocular zone

Front 263

the area that the R eye can see

Back 263

R visual hemifield

Front 264

the are that only the R eye can see

Back 264

R monocular zone

Front 265

why don't we notice the blind spot during binocular or monocular vison?

Back 265

during binocular viewing, the monocular visual fields overlap to cover up the blind spot

during monocular viewing, the missing part of the visual field isn neurally filled in

Front 266

the __ exits the L and R eyes at the optic disks and passes through holes in the floor of the skull

Back 266

optic

Front 267

the __ is the joining of the optic nerves of teh eye just above the pituitary gland

Back 267

optic chiasm

Front 268

at the optic chiasm, the axons originating in the __ retinas cross from one side to the other

Back 268

nasal

Front 269

__ are axons projecting from the optic chiasm toward specific regions of the brain

Back 269

optic tracts

Front 270

where does light from the R binocular hemifield go in the eye and the brain?

Back 270

L temporal and R nasal remiretina

goes to L side of brain

Front 271

contralateral and ipsilateral inputs project ot different layer of teh __ to create representation of the contralateral visual hemifield

Back 271

LGN

Front 272

1,4, and 6 are the __ layers of the LGN

Back 272

contralateral

Front 273

2, 3, and 5 are __ layers of the LGN

Back 273

ipsilateral

Front 274

layers __ and __ are the largest in the LGN

Back 274

1, 2

Front 275

at the LGN, the inputs from the two eyes are kept __

Back 275

separate

Front 276

in the R LGN, the R eye ispilateral axons synapse in LGN cells in layers __, __, and __. the L eye contralateral axons synapse on cells in layers __, __, and __

Back 276

2, 3, 5

1, 4, 6

Front 277

the R LGN recieves information about the __ visual field

Back 277

left

Front 278

ventral layers 1 and 2, teh __ layers contain large neurons

Back 278

magnocellular

Front 279

__ types retinal ganglion cells proejct in the magnocellular layer

Back 279

M-type

Front 280

the four dorsal layers 2, 4, 5, and 6 aer the __ LGN layers containing smaller cell types

Back 280

parvocellular

Front 281

__ type retinal ganglion cells project in teh parvocellular LGN layer

Back 281

P type

Front 282

tiny neurons between the P and M layers that has inputs arising from odd retina ganglion cels that cannot be classified as P or M cells

Back 282

koniocellular layers

Front 283

LGN cells project to the primary visual cortex through the __

Back 283

optic radiation

Front 284

what are the three pathways from the retina to the visual cortex?

Back 284

magnocellular pathway

parvocellular pathway

koniocellular pathway

Front 285

cells in the striate cortex that recieve input from the __ pathway have binocular receptive fields, sense brightness but not color, and have direction selectivity which helps to analyze object motion

Back 285

magnocellular pathway

Front 286

cells in teh strate cortex that recieve input from teh __ pathway have binocular, rectangular receptive fields, are very sensitive to wavelength of light (green and red), and are sensitive to stimulus oreintation which helps to analyze object shape

Back 286

parvocellular pathway

Front 287

cells in the striate cortex that help to analyze the object color blue

Back 287

koniocellular pathway

Front 288

in teh visual system, action potentials are only generated when an object is __ to the receptor field

Back 288

parallel

Front 289

in teh parvocellular pathways, if an object is changing direction, it __

Back 289

can't sense it and theres not firing

Front 290

structures in the brain stem involved in oreinting the eye toward a stimulus that initially appears in teh peripheral field of vision

Back 290

superior colliculus

Front 291

output from the superior colliculus goes to motor centers responsible for __

Back 291

orienting behaviors (visual movement)

Front 292

detection of stimulus and movement toward objects in teh visual field even when visual perception is lost is mediated by teh visual pathway passing through the __

Back 292

superior colliculus

Front 293

functions as an internal biological clock, synchronizes sleep/wake cycles among other biological rhythms, cycles are endogenous (internal), external timing cues adapt teh rhythm to the environment (sunlight, noise, social interactions, and alarm clocks). clocks can be reset

Back 293

suprachiasmatic nucleus

Front 294

regulates the timing of sleep but is not reponsible for sleep itself

Back 294

suprachiasmatic nucleus

Front 295

respnosible for the light reflex (where a light shining in one eye causes its pupil to constirct. also causes the puil to constrict in the other eye as well.

Back 295

pretectum

Front 296

the pupillary constiction reflex is mediated by retinal ganglion cells that project to the __

Back 296

pretectum

Front 297

synchronizes sleep and wakefulness with the daily dark/light cycle

is responsive to day length for regulating circadian and seasonal rhythms

Back 297

hypothalamus

Front 298

used for identifying objects

Back 298

the ventral visual pathway

Front 299

an image of a cat in your lowre right visual field would fall on:

Back 299

teh upper nasal retina of our R eye and teh upper temporal retina of teh L eye

Front 300

sued for determinng object position in space

Back 300

the dorsal visual pathway

Front 301

the retina and photreceptors are __ and the ganglionic cells are the __

Back 301

transducers, encoders

Front 302

sound vibrations travel as __

Back 302

longitudinal waves

Front 303

sound travels faster in __ than in __

Back 303

water, air

Front 304

the simplest, most fundamental type of vibration, contains only one signle frequency of vibration

Back 304

pure tones

Front 305

the number of compressed or rarefied patches of molecules that pass by out ears each second.

Back 305

frequency

Front 306

one __ of sound is the disatnce between successive compressed patches

Back 306

cycle

Front 307

teh time duraction of one cycle of vibration in seconds (time between two crests)

Back 307

period

Front 308

if teh period increases, frequncy, __

Back 308

decreases

Front 309

if teh frequency increases, pitch __

Back 309

increases

Front 310

if amplitude increases, __ increases

Back 310

volume

Front 311

can sound travel in a vacuum?

Back 311

no. no medium.

Front 312

__ and __ depend on teh source of teh sound alone

Back 312

frequency, period

Front 313

teh number of cycles per second (unit of frequency)

Back 313

hertz

Front 314

teh spacing betwen cycles in meters. depends on teh source of the sound and teh medium in which it travels

Back 314

wavelength

Front 315

our range of hearing is __

Back 315

20-20,000 Hz

Front 316

the difference in pressure between teh compressed and rarefied patches of air (determines loudness)

Back 316

intensity (amplitude)

Front 317

complex sounds having no dominant rhythmicity get perceived as __

Back 317

noise

Front 318

we recognize a sound when it has a __

Back 318

dominant rhythmicity

Front 319

a measure of sound intesnity

Back 319

decibel

Front 320

where is hearing at its best?

Back 320

2 K Hz

Front 321

the condition in which hearning at high frequencies is lost during old age

Back 321

prebycusis

Front 322

the outer ear includes the __ and __

Back 322

pinna and auditory canal

Front 323

the __ acts as a funnel to magnify pressure toward the auditory canal

Back 323

pinna

Front 324

part of the ear that vibrates relative to frequncy

Back 324

tympanic membrane

Front 325

in air, wound waves have low pressures and cause large displacements of air molecules meaning it has a __

Back 325

low inpedance

Front 326

in water, sound waves have high pressures and cause small displacements of molecules

Back 326

high impedence

Front 327

what is the "matching device" in teh ear to make sure that sound in the air is 100% transmitted into the water?

Back 327

ossicles

Front 328

in order for soundwaves traveling through air pass into the fluid of the cochlea ,the pressure on teh __ must be greater than teh pressure on teh __

Back 328

oval window, tympanic membrane

Front 329

what are two ways to increase pressure on a membrane?

Back 329

increasing force (movement of ossicles to act on oval window)

reducing SA of membrane (SA of oval window is less than tympanic membrane)

Front 330

teh middle ear magnifies the sound force at the oval window 1.5 x and reduces the dsplacement of air molecules 1.5 x these factors combine to make the pressure at teh oval window about __ greater than that of teh tympanic membrane

Back 330

20

Front 331

mechanical contrl of ear sensitiviey is regulated by __ and __ muscles (contraction reduces sound)

Back 331

tensor tympani, stapedius

Front 332

the __ and __ muscles contract reflexively at loud sounds to protect the auditory apparatus

Back 332

tensor tympani, stapedius

Front 333

the reflexive contraction fo tensor tympanii/stapedius has a slight __ so it does not protect against sudden loud sounds

Back 333

delay

Front 334

the stapedius and tensor tympani contract right before __

Back 334

speaking

Front 335

the __ includes the cochlea and labyrinth

Back 335

inner ear

Front 336

the __ and associated structures contain auditory receptors that are haircells with sterecilia

Back 336

organ of corti

Front 337

hair cells synapse on neurons whose axons enter the __, and whose cell bodies are located in teh __

Back 337

auditory nerve, spiral ganglion

Front 338

teh __ holding the hair cells vibrates easily at sound frequencies

Back 338

basilar membrane

Front 339

why does the basilar membrane vibrate easily at sound frequencies?

Back 339

coling of cochlea

membrane is wider at abex and stiffness decreases from base to apex (main)

Front 340

if a sound frequency is __, the stiffer base will vibrate and teh pressure wave will not propagate to the apex

Back 340

high

Front 341

if a sound frequency is __, the stiffer base will not vibrate but the wave will move to the floppy apex

Back 341

low

Front 342

teh __ is the filter of teh hair cell

Back 342

tectorial membrane

Front 343

at __ frequncy, teh tectorial membrane allows cilia to bend freely, with a __ frequency, it doesn't allow cilia to move (holds in place)

Back 343

low, high

Front 344

bending of the sterocilia is produced by the __ of the basilar membrane

Back 344

upward motion

Front 345

movement of teh ossicls in the middle ear:

A: can be increased by contraction teh tensor tympani and stapedius muscles

B: transfers sound pressure waves from water to air

C: results in deafness

D: is reduced just prior to speaking

Back 345

D

Front 346

explain cochlear amplicfication

Back 346

outer hair cells respond to sound with a receptor potential and a change in length

movement of sterocilia cause opening of K which depolarizes the cells. opens voltage gated Ca channels which cause NT release

Front 347

what kind of sensory cell has the least amount of cells?

Back 347

hair (inner hair to be exact)

Front 348

what is the auditory pathway?

Back 348

spiral ganglion--auditory nerve--ventral cochlear nucleus--superior olive (where pitch/sound is sensed)--lateral lemniscus--inferior colliculus (auditory information integrated here--MGN--auditory cortex

Front 349

part of auditory pathway where pitch/intesity it sensed

Back 349

superior olive

Front 350

part of auditory pathway where audtory information is integrated

Back 350

inferior colliculus

Front 351

sound processing begins in the __

Back 351

cochlear nuclei

Front 352

the systematic organization within an auditory structure based on characteristic frequency.

Back 352

tonotopy

Front 353

allows our brain and receptor cells to localize frequencies of sound

Back 353

tonotopy

Front 354

what are the two ways sound coding is done?

Back 354

rate (as intensity increases, axons fire more rapidly)

recruitment: as intensity increases additional receptors get recruited

Front 355

T/F auditory neurons are most responsive to sound at one frequency called its characteristic frequency

Back 355

TRUE

Front 356

what is phase locking?

Back 356

the brains ability to derive the frequeqncy of a sound based on the number of rythmic AP that are released

Front 357

when is tonotopy and phase locking used?

Back 357

at low frequencies, phase locking is used

at intermediate frequencies, both are used

at high frequencies tonotopy is used

Front 358

which of teh following is true about outer hair cells:

A: transduction of a sound wave by outer hair cells begins with the bending of the cells body

B: many afferent axons of cochlear ganglion cells innervate one outer cell

C: there are very few outer hair cells compared to inner hair cells

D: teh cell body of outer hair cells shortens when depolarized and lengthens when hyperpolarized

Back 358

D

Front 359

what two things affect localization of sound in teh horizontal plane?

Back 359

interaural time delay, interaural intensity difference

Front 360

the time difference between teh sound arriving at one ear and then the other ear. provides a cue to the location of a sound

Back 360

interaural time delay

Front 361

interaural time delay does not help to localize sound when a __ sound is emitted

Back 361

continuous

Front 362

how are continuous sounds localized?

Back 362

interaural intensity

Front 363

how does interaural intensity work on sound localization?

Back 363

teh peak of the sound wave reaches one ear before the other, the head casts a sound shadow cuasing a more intense sound in one ear than the other

Front 364

what part of the auditory pathway functions to decode interaural delay?

Back 364

superior olive

Front 365

localization of sound in teh vertical plane is based on sound reflection from the __

Back 365

pinna

Front 366

in your opinion, how might tatoos and piercings affect individuals hearning?

A: may not be able to hear soft sounds

B: may have difficulty localizing the sound of a car coming from his right

C: may have difficulty localizing the sound of a cat purring at his feet

D: may not be able to hear high pitched sounds

Back 366

C