Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
119 Cards in this Set
- Front
- Back
Sensory Receptor
|
a structure that specialized to detect a stimulus, ex. simple- nerve ending, ex. complex- sense organ
|
|
What are the general properties of receptors?
|
1. transduction
2. receptor potential 3. sensation |
|
transduction
|
the conversion of one form of energy to another
stimulus energy into nerve signals |
|
receptor potential
|
small, local electrical change on a receptor cell brought about by an initial stimulus- releases neurotransmitter in response to stimulus
|
|
sensation
|
a subjective awareness of the stimulus
|
|
Sensory receptors transmit 4 kinds of info
|
modality
location intersity duration |
|
modality
|
type of stimulus or sensation it produce ( all action potentials for vision, hearing and ect. are identical)
|
|
location
|
encoded by which nerve fibers are issuing signals to the brain
|
|
receptive field
|
area that detects stimuli for a neuron sensory
|
|
intensity
|
encoded in 3 ways- which fibers, how many and how fast
ex. pain is mild or excruciating |
|
duration
|
how long the stimulus lasts
|
|
sensory adaptation
|
if stimulus is prolonged the firing of the neuron gets slower over time and we become less aware of the stimulus
|
|
phasic receptor
|
generate a burst of action potential when 1st stimulated then quickly adapt and sharply reduce or stop signaling even if the stimulus continues
|
|
tonic receptor
|
adapt more slowly and generate never signals more steadily ex. body position, muscle tension and joint motion
|
|
general senses
|
structurally simple receptors- one or a few sensory fibers and a little connective tissue, very few fibers
|
|
unencapsulated nerve endings
|
dendrites not wrapped in connective tissue including free nerve endings, tactile disces, and hair receptors
|
|
free nerve endings
|
respond to falling and rising of tempeture and for pain located in skin and mucous membranes
|
|
tactile discs
|
tonic receptors for light touch through sense of textures, edges and shapes and located on basal layer of the epidermis
|
|
hair receptors
|
monitor movement of hairs and located on base of hair follicle
|
|
encapsulated nerve endings
|
nerve fibers that are wrapped in glial cells or connective tissues and enhances sensitivity or makes it more select
|
|
tactile corpuscles
|
are phasic receptors for light touch and texture
|
|
Krause end bulb
|
are ovoid bodies composed of a connective tissue sheath around a sensory nerve fiber and tactile in mucous membrane
|
|
lamellated Pacinian corpuscles
|
phasic receptors for deep pressue, stretch, tickle and vibration
|
|
bulbous ruffini corpuscles
|
tonic receptors for heavy touch, pressure, stretching of the skin and joint movement
|
|
pain
|
disconfort caused by tissue injury or noxious stimulation and typically leading to evasive actions
|
|
nociceptors
|
two types providing different pain receptors- occur in the meminges of the brain and play an important role of headaches
|
|
fast pain
|
travels in myelinated fibers at 12- 30
sharp locaized stabbing pain |
|
bradykinin
|
most potent pain stimulus known- hurts intensely when injected under the skin- ex. histamin, prostaglandin, and serotonin
|
|
slow pain
|
travels unmyelinated fibers- long lasting, dull and diffuse feeling
|
|
referred pain
|
pain in the viscera mistakenly thought to come from skin- convergence of neural pathways in the cns
|
|
gustation
|
sensation that results from the action of the chemicals on the taste buds
|
|
4 types of lingual papillae
|
filiform papilla
fungiform vallate foliate |
|
filiform papillae
|
tiny spikes without taste buds
- important for texture and grooming |
|
foliate papillae
|
form parallel ridges on sides of the tongue- weak in humans and no tast buds
|
|
fungiform
|
shaped like mushrooms 3 taste buds and mainly shaped on the apex at tips of tongue
|
|
vallate
|
large papilla arranged in a V at the rear of the tongue- many contain half the taste buds
|
|
taste cells
|
more or less banana shaped and have a tuft of apical microvilli
|
|
taste hairs
|
are surface receptors for taste molecules
|
|
taste pores
|
a pit on epithelial surfact on the tongue that synapse and release neurotransmitters onto sensory neurons
|
|
basal cells
|
stem cells that multiply and replace taste cells that have died
|
|
Physiology of taste (5)
|
salty
sweet sour bitter umami |
|
salty
|
produced by metal ions
|
|
sweet
|
produced by organic compounds and associated with carbohydrates
|
|
sour
|
associated with acids
|
|
bitter
|
associated with spoiled foods and alkaloids
|
|
umami
|
meaty taste produced by amino acids
|
|
olfaction
|
the receptors for sense of smell
|
|
olfactory mucosa
|
the roof of the nasal cavity the receptor cells
|
|
olfactory cells
|
10 to 20 million and in rest of nasal cavity
|
|
olefactory hairs
|
cilia have biding sites for odor molecules and are immoble
|
|
hearing
|
a response to vibrating air molecules
|
|
equilibrium
|
the sense of motion, body orientation and balance
|
|
sound
|
any audible vibration of molecules
|
|
pitch
|
our sense of whether a sound is high or low
|
|
frequency
|
the number of cycles per second (hertz)
|
|
infrasonic
|
sound below 20 hertz not detected by ears but sense vibration
|
|
ultrasonic
|
above 20,000 Hz inaudible vibrations
|
|
ear
|
has 3 sections outer, middle and inner ear- vibration converted into nerve signals
|
|
outer ear
|
a funnel for conducting vibrations to the tympanic membrane
|
|
auricle
|
or pinna on the side of the head shaped and supported by elastic cartilage except for the earlobe
|
|
guard hairs
|
stiff hairs on outer end of canal to protect
|
|
cerumen
|
earwax! is in the canal
the secretion mixes with dead skin sticky and coats the guard hairs making more effective in blocking and has lysosomes to inhibit bacteria |
|
middle ear
|
located in the air filled tympanic cavity of the temporal bone
|
|
tympanic membrane
|
closes the inner ear of the auditory canal and seperates it from the middle ear
|
|
tympanic cavity
|
is continuous with mastoid air cells and contains auditory ossicles
|
|
malleus
|
the enlongated handle attached to the inner surface of the tympanic membrane
|
|
incus
|
2nd bone that has a roughly triangle body that articulates with the malleus
|
|
stapes
|
has an arch and footplate which gives it the stirrup shape
|
|
auditory tube
|
connects middle ear cavity to nasopharynx
|
|
cochlea
|
organ of hearing a coiled tube that arises from the anterior side of the vestibule
|
|
scala vestibuli
|
fluid filled chamber the superior chamber filled with perilymph
|
|
scala tympani
|
the inferior chamber that communicates with the other channels at the apex of the cochlea
|
|
scala media
|
the middle chamber (a triangular space) filled with endolymph aka cochlear duct
|
|
vestibular membrane
|
thin layer that seperates the scala media from the scala vestibuli
|
|
basilar memberane
|
thicker membrane that seperates scala tympani and scala media
|
|
organ of corte
|
acoustic organ- converts vibrations into nerve impulses and composed of hair cells and supporting cells
|
|
equilibrium
|
coordination, balance, and orientation in three dimensional space
|
|
vestibular apparatus
|
receptors for equilibrium- consists of 3 semicircular ducts and 2 chambers (saccule and posterior utricle)
|
|
semicircular ducts
|
filled with endolymph, detects acceleration, and stimulated by rotation of the head
|
|
crista ampullaris
|
consists of hair cells buried in a mound of gelatinous membrane caled the cupula
|
|
2 chamber of vestibule
|
saccule and utricle and responsible for static equilibrium and linear acceleration
|
|
macula
|
patch of hair cells
|
|
macula sacculi
|
lies vestically on the wall of saccula
|
|
macula utricle
|
lies horizontally on floor of utricle
|
|
static equilibrium
|
the perception of the orientation of the head when the body is stationary
|
|
dynamic equilibrium
|
perception of motion or acceleration
|
|
otoliths
|
calcium carbonate protein granules
|
|
vision
|
perception of objects in the enviorment of the light that they emit or reflect
|
|
light
|
visible electromagnetic radiation, human vision is 400 to 750 nm
|
|
ultraviolet
|
<400 nm
|
|
infrared
|
>750 nm
|
|
eyebrows
|
protect eyes from glare and perspiration
|
|
eyelids
|
block objects, moisten eyes and prevent stimulus
|
|
tarsal glands
|
secret oil that reduces tear evaporation and coats eye
|
|
eye lashes
|
help keep debris off eyes
|
|
conjunctiva
|
transparent mucous membrane that covers the inner surface of the eyelid and anterior surface of the eyeball except cornea- richly innervated and vascular
|
|
lacirmal apparatus
|
tears to flow across eyeball, deliver oxygen and nutrients and prevent infections with a lysosome
|
|
3 principle layers of the eyeball
|
tunic-3 layers form walls
optical- admits and focuses light neural- retina and optic nerve |
|
tunics of the eyeball
|
tunic fibrosa
tunic vasculosa tunica interna |
|
tunic fibrosa
|
ourter fibrous layer contains sclera and cornea
|
|
sclera
|
white of the eye
|
|
cornea
|
transparent area of sclera that admits light into the eye
|
|
tunic vasculosa
|
middle vascula layer contains choroid body, ciliary body and iris
|
|
choroid layer
|
highly vascular, deeply pigmented layer of tissue behind the retina
|
|
ciliary body
|
extension of choroid that forms a muscular ring around lens- supports lens and iris and secretes aqueous humor
|
|
iris
|
colored diaphragm controlling size of pupil- melanin produces brown and in chromatophores
|
|
tunica interna
|
retina and beginning of optic nerver- transmit elements that admit light rays refract them and focus images on the retina
|
|
optical component
|
cornea, aqueous humor, lens and vitrous body
|
|
cornea
|
anterior transparent cover
|
|
aqueous humor
|
serious fluid, posterior of cornea and anterior to lens
|
|
lens
|
change shape to help focus light
|
|
vitreous body
|
filled space between lens and retinas
|
|
neural component
|
retina and optic disc
|
|
retina
|
forms from a cup shaped outgrowth of the deincephalon
|
|
optic disc
|
blind spot- optic nerve exits posterior surface of the eyeball
|
|
rods
|
night vision- contain visual pigment rhodopsin- opsin and retinal
|
|
cones
|
color photopic, day vision- contain photopsin- retinal moiety and opsin moiety- 3 kinds of cones
|
|
cataract
|
clouding of the lens
|
|
glaucoma
|
elevated pressure within the eye due to obstruction f scleral venous sinus and improper drainage a aqueous humor
|