NB14 Flashcards
Hair follicle receptors
Description: A-beta fibre wrapped around hair in epidermis and dermis, unencapsulated detect:motion
Free nerve endings
Description: C fibres with dendritic tree in epidermis or A-delta with dendritic tree in epidermis detect nocious stimuli in the skin
Meissner corpuscle
Description: nuclei in epidermis info carried away on A-beta fibre in dermis encapsulated detect: tap, flutter 5-40 Hz
Merkel cell
Description: cell in epidermis info. carried away on A-beta unencapsulated detect pressure (the harry potter one)
Pacinian corpuscle
deep in dermis many llamelae around A-beta nerve ending encapsulated detect vibration 60-300Hz
. Define Encapsulated receptors
have a special capsule which encloses a nerve ending.
Unencapsulated receptors - define
these have no special structure and are basically free nerve endings. Examples are pain receptors, temperature receptors, Merkel disks (touch), hair root plexus.
Ruffini corpuscle
Description: deep in dermis free ______ endings info carried on A-beta encapsulated Detect: stretch type movemrtn and slip ( like a penguin with ruffled feathers)
Lateral inhibition
bipolar nerve with stronger impulse inhibits 2nd order neurones receiving impulses from peripheral bipolar neurones
Divergence
1st order neurone synapses with many 2nd order synapsing with many 3rd order
Convergence
2 or more 1st order neurones synapse on the same 2nd order neurone
Sensory receptors in the skin that are rapid adapting
meissner corpuscle , some hair follicle receptors and pascinian corpuscles are all ________ adapting.
Sensory receptors in the skin that are slow adapting
merkel cells, some hair follicle receptors and ruffini corpuscles are all ________ adapting.
rapid adapting
receptor responds to application and removal of stimulus, not for full duration of a maintained stimulus. detects vibrations
slow adapting
receptor responds to full duration of a maintained stimulus. detects between hard and soft touch