Ch 14 Flashcards by Kennedy Chrest

sensory systems vs sense organs

sense organs = complex structure containing multiple tissues working together to allow an organ to detect an incoming stimulus

sense system = sense organs + CNS processing areas

How well did you know this?

Not at all

Perfectly

what’s a sensory receptor cell

specialized cell that can detect incoming sensory stimuli

How well did you know this?

Not at all

Perfectly

what are receptor proteins

in the membrane of sensory receptor cells + directly interact with stimulus

How well did you know this?

Not at all

Perfectly

receptor cells _____ stimulus energy into ____ ____ _____ called a receptor potential, which can trigger what

transducers stimulus energy into graded electrical signal

receptor potential can trigger action potentials

How well did you know this?

Not at all

Perfectly

3 forms of stimulus energy

chemical
mechanical
EM energy

How well did you know this?

Not at all

Perfectly

what are chemoreceptors and describe how they work

detect chemicals in mouth, nose and body fluids

receptor changes shape -> signal transduction -> ion channels open/close -> change membrane potential = graded potentials

How well did you know this?

Not at all

Perfectly

insect olfactory receptors detect ____ which….

pheromones
- which open ion channels and depolarize membrane

How well did you know this?

Not at all

Perfectly

the _____ organ is an olfactory organ in most terrestrial vertebrates

the vomeronasal

How well did you know this?

Not at all

Perfectly

what are mechanoreceptors and the process

sensitive to mechanical stimulus

receptor changes shape -> signal transduction -> ion channels open/close -> change membrane potential = graded potentials

How well did you know this?

Not at all

Perfectly

what’s special about mechanoreceptors

the can ignore a stimulus over time ! ex. like jewelry/ underwear on skin

How well did you know this?

Not at all

Perfectly

tonic vs phasic receptor

tonic = train of impulses continues during prolonged stimulus (doesn’t change)
ex. pain

phasic = train ceases during prolonged stimulus (adapts)
ex. go nose blind

How well did you know this?

Not at all

Perfectly

hair cells are an example of ______ and how do they work

mechanoreceptors

more K in = movement of stereocilia to the right towards kinocilium cause depolarization = releases neurotransmitters (Ca2+)

How well did you know this?

Not at all

Perfectly

what are photoreceptors

detects light stimulus

receptor changes shape -> signal transduction -> ion channels open/close -> change membrane potential = graded potentials

How well did you know this?

Not at all

Perfectly

describe rod receptor potential in dim vs bright light

dim = rods are depolarized
- influx of Na

bright = rod hyperpolarizes
- closed Na channels

How well did you know this?

Not at all

Perfectly

ionotropic transduction

receptor molecule itself is an ion channel
~ receives sensory stimulus and transduces it into electrical signal

How well did you know this?

Not at all

Perfectly

metabotropic transduction

sensory receptors acts as a G-protein coupled receptor
~ indirectly permeability via second messengers cAMP

How well did you know this?

Not at all

Perfectly

extero vs interoceptors

extero = sensory cells that respond to stimuli from outside the body
(light/sound)

intero = respond to internal stimuli
(blood pH)

How well did you know this?

Not at all

Perfectly

4 processes of sensation

detection of stimuli
signal transduction
generation of action potentials
integration of sensory input

How well did you know this?

Not at all

Perfectly

what is special about touch and smell and what do the others do

are sensory neurons!!!

others release neurotransmitters

How well did you know this?

Not at all

Perfectly

1st, 2nd and 3rd order neurons

1st = pass info from sensory receptors to CNS

2nd = receives info from 1st order neuron (in the brain/spinal cord)

3rd = receives 2nd order and sends to sensory area of cortex

How well did you know this?

Not at all

Perfectly

stereocilia are connected together via a ____ which has …..

tip link
- has mechanically gated K ion channels

adult mammals lack _____

kinocilium

do epithelial cells have polarity ? what does each do

YES

apical
= faces outside enviro
- hair + tip link

basolateral
= faces inward toward tissue/blood
- release of neurotransmitter

mammalian ear purpose

-receive and amplify sound
~detect amplitude and frequency

all vertebrate have an ____ ear, non mammalian vertebrates lack ____ ears

inner ear lack outer ear

pitch vs intensity (loudness)

pitch = determined by frequency intensity = depends on amplitude

in the cochlea what contains perilymph and what contains endolymph

peri = - scala vestibuli - scala tympani endo = - cochlear duct

what is the organ of corti

contains a single row of inner hair cells and 3 outer hair cells *supported by basilar membrane inner - hearing outer - increase sensitivity

cochlea has ___ chambers and describe the 2 membranes

3 chambers Basilar membrane = sound displaces this membrane to cause the hair cells to bend - at base rigid *high pitch - by apex (tip/end) flimsy *low pitch Tectorial membrane = lies above hair cells in organ of corti

tympanic membrane

separates outer ear from middle ear - vibrates from sound waves - vibrations pass along the ossicles (amplify) and then carry the sound into the inner ear

sound pathway steps (4)

1. sound waves hit eardrum (tympanic membrane) and cause it to vibrate 2. ear bones (ossicles) also vibrate and amplify 3. the last bone stapes pushes on the oval window making waves in the inner ear fluid 4. low pitched sounds DONT active hearing cells / sounds we can hear travel through cochlear duct, shake the basilar membrane and bend the inner hair cells

human sound localization

good at capturing horizontal sound not vertical

2 components of vestibular apparatus (balance)

- 3 semicircular canals (angular acceleration) up&down - 2 otolith organs (linear acceleration & tilted position) fast&slow

what are the 2 otolith organs and describe

- saccule = vertical macula - utricle = horizontal macula *linear acceleration and tilted position

describe the 3 semicircular canals

- hair cells embedded in cupula - cristae detect angular acceleration (head shake)

do hair cells fire action potentials ?

NO, only detect movement the sensory neurons generate AP

photoreceptors and 2 major types

transduce energy from light into an electrical signal - Ciliary = cilia containing photopigment molecules *vertebrates only have these - Rhabdomeric = microvilli increasing SA

photoreceptor only generate _____ NOT ______

graded potentials NOT action potentials

2 mammal photoreceptors

rods cones

retina contains _____

photoreceptors

cones are a 1-1 meaning what

for one cone there is one bipolar cell *high acuity

rod’s function in ___ light while cones function in ___

rods = dim light cones = bright light

light triggers the conversion of …… (shape)

retinal (11-cis/ bent) to all trans retinal (straight)

opsin protein + retinal =

photopigment (ex.rhodopsin)

steps of phototransduction (4)

-light changes 11-cis to all trans retinal in rhodopsin - activates G protein (transducin) - cGMP phosphodiesterase converted cGMP to non cyclic GMP *cGMP causes Na channel to open

in light there is more ____ in the dark there is more ______ which causes an influx of ____

light = more non cyclic GMP dark = more cGMP and Na influx which depolarizes the membrane

what is bleaching

breakdown of opsins when exposed to light

what is needed for the regen of photopigments

Vitamin A

what can cause excitation or inhibitor between the photoreceptor and bipolar cell

glutamate

describe breakdown of ON-center ganglion cells in light vs dark

LIGHT - stop releasing glutamate - activated ON bipolar cells - removes metabotropic inhibition - depolarizes and releases excitatory glutamate DARK - activates glutamate MR - decreases excitatory glutamate release - inhibitory and causes hyperpolerization

both eyes receive input from ….

the left AND right visual fields