Bio Ch 41

Front 1

Sensory receptors

Back 1

transduce or convert the energy of the stimulus to elctrical signals into graded potntials that result in action potentials

Front 2

Interoreceptors

Back 2

w/in body orgns that detect changes in pH, temperature, chemical composition.

Front 3

Sensory rceptors steps

Back 3

-absorb a small amt of energy from some stimulus
-energy transduction
-produce receptor potntial

Front 4

Energy transduction

Back 4

Convert energy of stimulus into electrical energy

Front 5

Receptor potential

Back 5

Depolarization or hyperpolarization of th membrane

Front 6

Sensory adaptation

Back 6

Decrease in frequency of action potntials. response to a continued, constant stimulus is maintained.

Front 7

Mechanoreceptors

Back 7

activated whn they change shape as a result of bing mechnically pushed or pulled

Front 8

Proprioceptors

Back 8

-help maintain postural relations
-located w/in muscles, tendons & joints
-respond to tension & movement
-animals can perceive body parts position

Front 9

Stereocilia

Back 9

-projections found in hair cells
-Mechanical stimulation causes voltage changes.

Front 10

Vestibular apparatus

Back 10

-maintains equilibrium
-3componnts:
1-saccule
2-utricle
3-semicircular canals

Front 11

Saccule & Utricle

Back 11

-detect the position of th head
-house otoliths
-sensory cells ar hair cells. The stereocilia ar coverd by cupula

Front 12

Otoliths

Back 12

-housed by saccul & Utricles
-gravity detctors in th form of calcium carbonate ear stones
-embedded in th cupula

Front 13

Pull of gravity & otoliths

Back 13

gravity causes the otoliths press against th stereocilia, stimulating them to intitiat impulses.

Front 14

Saccule & Utricle

Back 14

-detect the position of th head
-house otoliths
-sensory cells ar hair cells. The stereocilia ar coverd by cupula

Front 15

Otoliths

Back 15

-housed by saccul & Utricles
-gravity detctors in th form of calcium carbonate ear stones
-embedded in th cupula

Front 16

Pull of gravity & otoliths

Back 16

gravity causes the otoliths press against th stereocilia, stimulating them to intitiat impulses.

Front 17

Semicircular canals

Back 17

-detection of the head
-turning movements is provided by 3 canals
-each canal is a hollow ring connected w/utricle.
-Filled with endolymph

Front 18

Endolymph

Back 18

fluid in semicircular canal

Front 19

Cochlea

Back 19

-hair cells detect pressure waves
-consists of 3 canals.
-organ of corti located on the middle canal

Front 20

organ of corti

Back 20

-contains hair cells which have stereocilia.
-hair cells rest in basilar membrane and are in contact with the tectorial membrane

Front 21

How sound travels thru the ear

Back 21

Sound waves:
(1)pass thru th extrnal auditory canal and vibrat the tympanic membrane
(2)vibrate thru the bones
(3)go thru the oval window into the cochleas

Front 22

Bones of the ears

Back 22

-amplify vibrations
-malleus: in contact w/ear drum
-incus
-stapes: in contact w/oval window

Front 23

Round window

Back 23

"escape valve" for pressure in the canals

Front 24

Eustachian tube

Back 24

-connects the middle ear region w/throat
-equalizes the pressure coming in and out

Front 25

Pressure waves in the cochlea

Back 25

-Waves are transmitted to the middle canal, where they produce vibrations in the basilar membrane.
-The pulsations cause the sterocilia to rub back and forth on the tectorial membrane
-stimulation of the sterocilia causes action potntials to be generated.
-these nerve impulses are transmitted to the brain via cochlear nerve.

Front 26

Hi-pitch sound

Back 26

waves have sufficient energy to distend the proximal portion of th basiliar membrane

Front 27

Low pitch sound

Back 27

waves can distend only the distal portion of the basilar membrane.

Front 28

chemoreceptive systms

Back 28

Gustation and olfaction

Front 29

Taste buds

Back 29

-capsule containing taste rceptor cells
-food molecules bind with specific receptor molecules
-receptor potential is generated, followed by an action potntial in an associated neuron, which carris the impulse to the brain.

Front 30

olfactory epithelium

Back 30

-found in the roof of the nasal cavity.
-olfactory cells are neurons
-tips bind with molecules in th air. which causes and action potential generated which travls to the brain

Front 31

Photoreceptors

Back 31

use pigments to absorb light energy

Front 32

Rhodopsins

Back 32

photopigments found in eyes

Front 33

Iris

Back 33

regulates the size of the pupil

Front 34

Choroid layer

Back 34

a sheet of cells filled with black pigment that absorbs xtra light,preventing light from being reflected into th photoreceptors that would cause blurring of images

Front 35

sclera

Back 35

tough, opaque, curved sheet of connective tissue that maintains rigidity of the eyeball

Front 36

Cornea

Back 36

transparent layer, thru which light enters

Front 37

Lens

Back 37

transparent, elastic ball

bends the light rays...and brings them to a focus on th retina

Front 38

Anterior cavity

Back 38

b/t the cornea & the lens is filled with aqueous fluid

Front 39

Postrior cavity

Back 39

b/t lens & retina. filled w/ vitreous body. Internal fluid pressure

Front 40

ciliary body

Back 40

where the choroid is thick and projects into the eyeball

Front 41

Accommodation

Back 41

the ability to change focus for near or far vision. with the aid of the ciliary muscle

Front 42

Retina

Back 42

-light sensitiv structure
-has rods and cones

Front 43

Rods

Back 43

function in dim light. not sensitive to colors. more numerous

Front 44

Cones

Back 44

respond to light at higher levels of intensity. responsible for color vision.

Front 45

Fovea

Back 45

where the cones are concentrated. region of sharpest vision.

Front 46

Optic disk

Back 46

area where the optic nerve passes out of the eyeball. "blind spot".

lacks rods and cones

Front 47

ability to see

Back 47

rhodopsin in the rod cells help aid in seeing

Front 48

rhodopsin

Back 48

2 parts:

opsin: large protein
retinal: form of vitamin A. cis and trans form exists

Front 49

Light & rhodopsin

Back 49

light transforms cis into trans. This causes the rhodopsin to change shape. Causing a receptor potential which is converted to an action potntial.