Anatomy & Physiology Ch.15 Special Senses Marieb

Front 1

4 traditional special senses:

Back 1

sight, smell, taste, hearing

Front 2

5th special sense:

Back 2

equilibrium

Front 3

explain touch:

Back 3

activity of all the senses as part of the nervous system

Front 4

where are equilibrium receptors housed?

Back 4

ear

Front 5

special sensory receptors are what kind of cell?

Back 5

distinct receptor cells

Front 6

our dominant sense?

Back 6

vision

Front 7

___% of sensory receptors in the body are found where?

Back 7

70 % / eyes

Front 8

how much of eye's surface is visible to us?

Back 8

1/6 th

Front 9

eye's accesory structures?

Back 9

eyebrows, eyelids, conjunctiva, lacrimal apparatus & extrisic eye muscles

Front 10

eyebrows' purposes?

Back 10

1. shade the eyes from sunlight 2. block forehead sweat from reaching eyes

Front 11

another name for eyelids?

Back 11

palpebrae

Front 12

2 eyelids seperated by?

Back 12

palpebreal fissure

Front 13

2 eyelids meet @ 2 ends of eye @ what?

Back 13

medial & lateral commissures (canthi)

Front 14

extra bit of flesh @ medial closure called what?

Back 14

lacrimal caruncle ("a bit of flesh")

Front 15

what do Asians have in their eyes that is different?

Back 15

epicanthic fold - (vertical fold of skin)

Front 16

eyelids are supported by?

Back 16

tarsal plates (connective tissue plates

Front 17

what msucle encircles the eye & what is it anchored to?

Back 17

levator palpebrae superioris muscles - anchored to the tarsal plates

Front 18

how often do we blink?

Back 18

every 3-7 seconds

Front 19

name 2 eye glands & their functions

Back 19

1. tarsal glands (modified sebaceous glands - produce oily lubrication for eyelid & eye) 2. ciliary glands (smaller sebaceous glands between the eyelashes)

Front 20

chalazion

Back 20

"swelling" - infection of a tarsal glad that creates a cyst.

Front 21

sty

Back 21

inflamation of a smaller eye gland

Front 22

conjunctiva & its purpose?

Back 22

eye's transparent mucous membrane - produces lubricating mucus & prevents eyes from drying out

Front 23

conjunctiva sections?

Back 23

palpebral conjunctiva (lines the eyelids), and bulbar conjunctiva (covers all but cornea - is very thin)

Front 24

space between conjunctiva-covered eyeball & eyelids?

Back 24

conjunctival sac (where a contact lens fits)

Front 25

conjunctivitis

Back 25

inflammation of the conjunctiva

Front 26

pinkeye

Back 26

bacterial or viral infection of the conjunctiva

Front 27

consists of lacrimal gland & its ducts? (& its purpose)

Back 27

lacrimal apparatus - drains excess lacrimal secretions into nasal cavity

Front 28

where is lacrimal gland (& its purpos)

Back 28

in orbit above lateral end of eyeball - releases dilute saline solution

Front 29

dilute saline solution released by lacrimal gland?

Back 29

lacrimal secretion or TEARS

Front 30

name the 4 rectus muscles and where they originate?

Back 30

superior, inferior, lateral, and medial rectus muscles - they originate at the annular ring

Front 31

2 additional extrinsic eye muscles

Back 31

superior oblique & inferior oblique

Front 32

why do we have the 2 obliques?

Back 32

the superior & inferior recti muscles can't elevate/depress eye without also turning it medially - these prevent this

Front 33

which cranial nerves contraol the 6 extrinsic eye muscles?

Back 33

all are controlled by occularmotor nerve EXCEPT lateral rectus (controlled by VI - Abducens, and Superios oblique - controlled by IV - troclear)

Front 34

name for seeing 2 diff images of same scene when drunk, etc?

Back 34

diplopia (double vision) - movements of extrenal muscles not coordinated (also from paralysis/weakness of extrinsic eye muscles)

Front 35

cross-eyed?

Back 35

Strabismus - congenital weakness of extrenal eye muscles

Front 36

3 layers (or tunics) of the eyeball? (f rom outer to inner)

Back 36

fibrous, vascular, & sensory ( or retina) layers

Front 37

make-up of the outer layer?

Back 37

dense avascular connective tissue

Front 38

fibrous tunic's 2 parts (& respective functions)?

Back 38

sclera (protects & shapes eyeball - insertion point for extrinsic muscles - continuous w/brain's dura matter) & cornea (window - lets light enter the eye - part of light-bending apparatus)

Front 39

another name for the vascular layer?

Back 39

uvea ("grape")

Front 40

3 major parts (& their functions) of the vascular layer?

Back 40

iris (alolows light in through pupil, dilates & constricts pupil w/2 smooth muscle layers), & Choroid (blood vessels bring nutirion to all layers, brown pigment absorbs light to stop reflection & resulting visual confusion), Ciliary body (important in controlling lens shape)

Front 41

what suspends the lens?

Back 41

ciliary zonule (or suspensory ligament)

Front 42

What secretes fluid into the anterior cavity of the eyeball?

Back 42

ciliary processes (contains capillaries to secrete the fluid)

Front 43

pupil constricts when?

Back 43

in near vision, bright light, when subject matter is appaling, in response to fear, & during problem solving

Front 44

the pupil dilates when?

Back 44

in distant vision and dim light, or durinf appealing subject matter,

Front 45

pupil dilation is controlled by?

Back 45

sympathetic nerve fibers

Front 46

pupil constriction is controlled by?

Back 46

parasympathetic nerve fibers

Front 47

irises contain what kind of pigment?

Back 47

only brown - (if there is limited pigment, light's wavelengths are scattered from unpigmented parts, and appear blue, grey, green, etc. w/this, the pigment is usually found on the back side of the iris)

Front 48

what are the 2 layers of the retina? (& functions)

Back 48

outer pigmented layer (absorb light to prevent scattering within the eye - also act as phagocytes to eat bad photoreceptor cells & store vitamin A), and inner neural layer (transparent, contains millions of photoreceptors, involved neurons, & glia).

Front 49

fusion between retina's iner neural layer & posterior margin of the ciliary body?

Back 49

ora serrata ("saw-toothed margin")

Front 50

3 types of neurons in neural layer?

Back 50

(from posterior 2 anterior): 1. photoreceptors 2. bipolar cells 3. ganglion cells

Front 51

fundus?

Back 51

posterior wall of the eye

Front 52

optic disc

Back 52

weak spot in the fundus - also called the blind spot

Front 53

rods

Back 53

4 dim light & peripheral vision. Can't provide sharp detail in images, or color vision

Front 54

cones

Back 54

bright light & provide high acuity(detail) images

Front 55

macula lutea

Back 55

lateral to the optic disc (blind spot), located escatly at eye's posterior pole, oval region

Front 56

fovea centralis

Back 56

tiny pit in middle of the macula lutea, contains only cones, NO layers in the way, so light gets directly to the cones - where light SHOULD hit naturally -glasses fix this if its not the case

Front 57

posterior segment

Back 57

large cavity filled with vitreous (glassy) humor - binds large amounts of waterm - formed embroyogically - its what reflects the sounds waves in an ultrasound

Front 58

3 purposes of the vitreous humor

Back 58

1. TRANSMITS light 2. SUPPORTS posterior surface of lens & holds neural retina firmly against the pigmented layer 3. adds 2 INTRAOCULAR PESSURE

Front 59

2 chambers of the anterior segment (& locations)

Back 59

1. anterior chamber (between cornea & iris) 2. posterior segment (between iris and lens)

Front 60

aqueous humor

Back 60

similar to blood plasma - fills anterior segment drains regularly & in constant motion - usually at about 12-20 mmHg (16 = normal)

Front 61

scleral venous sinus

Back 61

venous channel - encircles the eye drains the aqueous humor into the venous blood vessels

Front 62

glaucoma

Back 62

excessive pressure within the eye - happens if the drainage of aqueous humor is blocked

Front 63

lens

Back 63

crystalline (protiens aligned parallel-ly) - allows light to focus on the retina

Front 64

cataract

Back 64

clouding of the lens when protiens lay down differently - from nutrients not diffusing into the lens right

Front 65

diabetic cataracts

Back 65

looks like a peace sign on the eye

Front 66

refelction of light

Back 66

when it bounces at a right angle

Front 67

refraction of light

Back 67

when it bounces at an OBLIQUE angle

Front 68

passage of light into the eye?

Back 68

bends 3 times: 1. enters cornea (bends) 2. enters lens (bends) 3. leaves the lens (bends)

Front 69

emmetropic

Back 69

20/20 vision - normal - 20 feet away is farthest point @ which there is no change in lens shape is needed 2 focus

Front 70

adjustments eye makes for close vision

Back 70

1. ACCOMODATION of lenses 2. CONSTRICTION of pupils 3. CONVERGENCE of eyeballs

Front 71

accomodation

Back 71

increases refractory power of the lens

Front 72

presbyopia

Back 72

"Old person's vision" when you hit ~age 50, the lens won't bend any more, loss of flexibility = less ability to focus

Front 73

constriction of pupils

Back 73

step 2 of close vision focusing: makes pupil smaller

Front 74

convergence

Back 74

medial rotation of the eyeballs so each is directed toward the object being viewed (controlled by somatic motor fibers of occularmotor nerves(III), and medial rectus muscles)

Front 75

myopia

Back 75

"short vision" near sightedness - can't see distance - their light focuses in front of the retina

Front 76

hyperopia

Back 76

"far vision" far-sightedness - can't see close objects

Front 77

astigmatism

Back 77

unequal curvatures in cornea or lens (badly shaped eye) = blurry images

Front 78

outer segment of rods & cones

Back 78

RODS: slender/rod-shaped CONES: short & conical

Front 79

inner segment of rods & cones

Back 79

connects to cell body, which is continuous with the inner fiber bearing synaptic terminals

Front 80

visual pigments (photopigments)

Back 80

change shape as they absorb light - embedded in the disc areas of the plasma membrane

Front 81

how do photoreceptors respond to damage

Back 81

they don't - they're very vulnerable to damage and immediately begin to degenerate if the retina becomes detached - BUT also regenerate very quickly in normal situations

Front 82

what can stop regeneration of photoreceptors?

Back 82

Vitamin A shortage (these regenerate every day)

Front 83

retinal

Back 83

photopigment that combines protien called opsins to produce 4 different visual pigments

Front 84

rhodopsin

Back 84

purple pigment - important for low light situations

Front 85

what happens with photons hit an 11-cis isomer?

Back 85

it twists and snaps into a new configuration - the all-trans isomer

Front 86

excitation of rods happens when?

Back 86

low-light - rhodopsin is necessary

Front 87

bleaching of the pigment

Back 87

happens when rhodopsin is hit with photons and changes to all-trans isomer, and then the retinal-opsin combo breaks downs w/ help of enzymes

Front 88

excitation of cones happens when?

Back 88

in normal light -

Front 89

color blindness

Back 89

sex-linked recessive = more men have it - red-green is most common - from deficit of red-green cones

Front 90

transducin

Back 90

G protien that taken place in process that is normally inhibitory, but turns into an excitatory response (b/c ganglion cells generate action potentials)

Front 91

light adaption

Back 91

when we move from dark to light, bleaching is almost instant (b/c retina is still set for low light, but instantly responds

Front 92

dark adaption

Back 92

quick black out when moving into the dark - takes about 30 minutes to adjust fully b/c rods have been bleached by the previous light

Front 93

nyctalopia

Back 93

night blindness - from lack of Vit. A.

Front 94

retinosis pigmentosa

Back 94

rods are selectively destroyed- pigment epithelial cells are unable to recycle the tips of the rods as they get sloughed off

Front 95

primary visual cortex

Back 95

also called the striate cortex - in occipital lobe

Front 96

w/ a tramautic blow to the occipital lobe, what can happen?

Back 96

you can go blind

Front 97

chemoreceptors

Back 97

sensitive & respond to chemicals in aqueous solution

Front 98

olfactory receptive cells

Back 98

the more you have, the better your smell - shped like bowling pins

Front 99

filaments of the olefactory nerve

Back 99

slender, unmyelinated axons of the olefactory receptor cells gathered into smal fasicles

Front 100

german shepards can small ___times better than us

Back 100

20 X

Front 101

to smell, you need ___

Back 101

turbulence in your nose (sniffing)

Front 102

the olefactory pathway

Back 102

runs through the frontal lobe and connects to limbic system (Christmas buying sprees)

Front 103

what odors cause reflexive stopping of breathing?

Back 103

ammonia, strong chemical smells, etc

Front 104

whats special about taste buds?

Back 104

the only sense receptors made up of epithelium

Front 105

what are the 5 different tastes?

Back 105

sweet, sour, salty, bitter, umami

Front 106

umami

Back 106

cooked meat - on the back of the toungue (included MSG, and aspartate

Front 107

anosomias

Back 107

"without smells" when you can't smell - b/c of head injuries that tear olefactory nerves, aging, affter-effects of nasal cavity inflammation, or zinc deficiency

Front 108

uncinate fits

Back 108

olefactory hallucinations (rotting meat, etc) - olefactory auras happen for some epileptics

Front 109

auricle (or pinna)

Back 109

part of the outer ear - the elastic cartilage outside your head

Front 110

ceruminous glands

Back 110

produce cerumen / ear wax - excessive buildup can impair hearing

Front 111

tympanic membrane

Back 111

eardrum - boundry between the outer and middle ears - made of thin, translucent connectiuve tissue

Front 112

otitis media

Back 112

middle ear inflamation - common in kids - most common form of children's hearing loss - can be treated with anti-biotics

Front 113

myringotomy

Back 113

lancing of the eardrum 2 relieve pressure- implantation of a tiny tube that falls out within a year

Front 114

tensor tympani & stapedius mescles

Back 114

tighten to protect the 3 auditoruy ossicles in the middle ear - can't react quick enough to protect against axplosions = fractures in these bones = hearing loss/deafness

Front 115

name the 3 auditory ossicles

Back 115

1. malleus (hammer) 2. Incus (anvil) 3. stapes (stirrups)

Front 116

labyrinth

Back 116

another name for the middle ear

Front 117

mambranous labyrinth

Back 117

syeries of mambranous sacs & ducts contained in the bony labyrinth that follow its contours

Front 118

perilymph

Back 118

similar to CSF & continuous with it- conducts sounds vibrations involved in hearing and respond to mechanical forces during chages in body position & acceleration

Front 119

endolymph

Back 119

chemicall similar to intracellular fluid, but more K+ rich - conducts sounds vibrations involved in hearing and respond to mechanical forces during chages in body position & acceleration

Front 120

vestibule

Back 120

concerned with balance & proprioreception

Front 121

cochlea

Back 121

hearing organ - snail shaped - size of a split pea

Front 122

basically, how does process of hearing work?

Back 122

physical energy displacement is changed into electro-chemical impulses

Front 123

deafness

Back 123

hearing loss, no matter how slight

Front 124

2 types of deafness

Back 124

1. conduction deafness (something hampers sound conduction to the fluids of the internal ear) 2. sensoneural deafness (damage to neural structures)

Front 125

conduction deafness

Back 125

something hampers sound conduction to the fluids of the internal ear

Front 126

sensoneural deafness

Back 126

damage to the neural structures - due to stroke, tumor, or in-born problem

Front 127

tinnitus

Back 127

ringing or clicking sounds in the ear in the absence of auditory stimuli - similar to phantom limb pain

Front 128

meniere's syndrome

Back 128

Vertigo - standing erect is basically impossible - affects all 3 parts of the inner ear -

Front 129

otolithic membrane

Back 129

a jelly-like mass studded with tiny stones (otoliths)

Front 130

otoliths

Back 130

"ear stones" increase the otolithic membrane's weight & inertia

Front 131

crista ampullaris

Back 131

small elevation of the ampulla of each sami-circular canal- excited by head movement - specifically, rotational movement - fluid flows in opposite direction of movement