Exam 4- Sensory Flashcards
sensory receptors
neural structures that respond to stimuli by generating an action potential
function of sensory receptors
they can lead to, but do not directly provide themselves, sensation (awareness of stimuli) and perception
how are sensory receptors classified?
type of stimuli they detect
location
structural complexity
sensory receptors classified by structural complexity
simple receptors
complex receptors
sensory receptors classified by stimulus detected
mechanoreceptors thermoreceptors photoreceptors nociceptors chemoreceptors
sensory receptors classified by location
exteroreceptors
interoreceptors
proprioceptors
simple receptors
modified dendritic endings of sensory neurons
complex receptors
localized collection of cells associated with the special senses
(sense organs like eyeballs, ears, taste buds, olfactory receptors, etc)
what does a stimulus to a sensory receptor result in?
generator potential (excitatory or inhibitory)
mechanoreceptor
stimulus: mechanical energy/force
thermoreceptor
stimulus: thermal/heat energy
photoreceptor
stimulus: light energy
nociceptor
stimulus: pain or potentially dangerous stimuli
chemoreceptor
stimulus: chemical energy
if any receptor is overstimulated, it sends what type of signal?
pain
exteroceptor
stimulus is outside the body
ex: touch, pain, pressure, temp, sight, etc
interoceptor
stimulus is within body
ex: stretch, temp, chemical, etc
proprioceptor
stimulus is within muscles, joints, tendons, ligaments, and connective tissue
detects stretch and is involved with balance
free nerve endings
dendrite is available to be stimulated (no connective tissue wrapping)
do not have complex sensory structures
sensitive to painful stimuli, hot/cold, light touch
examples of receptors with free nerve endings
merkel discs
hair follicle receptors
itch receptors
merkel discs
sensory cells in deep epidermis that respond to light touch
nerve ending is free
hair follicle receptors
around base of hair follicle
detect when hair is bent
nerve ending is free
itch receptors
stimulated by touch (things like the sensation when you feel wool)
in dermis
nerve ending is free
encapsulated dendritic endings
dendrites are enclosed in connective tissue
have either a brush border or fluid-filled sacs at ends
examples of receptors with encapsulated dendritic endings
meissners corpuscles pacinian corpuscles ruffinis corpuscles muscle spindles golgi tendon organs joint kinesthetic receptors
meissners corpuscles
light touch receptors in superficial dermis
nerve ending is encapsulated