PNS Flashcards
Receptors can be classified by:
1
2
3
- type of stimulus they detect
- by body location
- by their structural complexity
Mechanoreceptor
responds to mechanical force such as touch, pressure (blood pressure), vibration, and stretch
Thermoreceptor
respond to temperature changes
Photoreceptor
respond to light
Chemoreceptor
respond to chemicals in solution (smell, taste, changes in blood or interstitial fluid)
Nociceptor
respond to potentially damaging stimuli that result in pain
Receptors by location
1
2
3
- Exteroreceptors
- Interoceptors
- Proprioceptors
Exteroceptors
sensitive to stimuli arising outside the body
Interoceptor (visoceptor)
responds to stimuli within the body
Proprioceptor
respond to internal stimuli in skeletal muscles, tendons, joints, and ligaments and in connective tissue coverings of bones and muscles.
advise the brain of body movement and how the organs containing these receptors are stretched.
general sensory receptors
1
2
- Encapsulated
2. Non-encapsulated
Nonencapsulated
1.
2.
3.
- Free nerve endings of sensory neurons
- Modified free nerve endings (Merkel discs)
- Hair Follicle Receptors
Free Nerve Endings
L:
S:
L: Exteroceptors, interoceptors S: Thermoreceptors (warm/cold), chemoreceptors (itch,pH), mechanoreceptors (pressure), nociceptors (pain, hot, cold, pinch, and chemicals
Merkel Discs and where are they found
L:
S:
L: Exteroceptors
S: Mechanoreceptors (light pressure), slowly adapting
basal layer of epidermis
Hair Follicle Receptors
L:
S:
L: Exteroceptors
S: Mechanoreceptors (hair deflection), rapidly adapting
Meissner’s corpuscles (tactile)
L:
S:
and where are they found
L: Exteroceptors
S: Mechanoreceptors (light pressure, discriminative touch, vibration of low frequency), rapidly adapting
dermal papillae of hairless skin
Pacinian corpuscles (lamellar)
L:
S:
and where are they found
L: Exteroceptors, interoceptors, and some proprioceptors
S: Mechanoreceptors (deep pressure, stretch, vibration of high frequency), rapidly adapting
largest and respond only at start of stimuli
Raffini endings (Bulbous corpuscles)
L:
S:
and where are they found
L: Exteroceptors, proprioceptors
S: Mechanoreceptors (deep continuous pressure and stretch), slowly or non-adapting
deep in dermis, hypodermis, and joint capsules
Muscles Spindles and where are they found
L:
S:
L: Proprioreceptors
S: Mechanoreceptors (muscles stretch, length)
skeletal muscles
Tendon Organs and where are they found
L:
S:
L: Proprioceptors
S:Mechanoreceptors (muscle stretch, tension)
tendons
Joint Kinesthetic receptors and where are they found
L:
S:
L: Proprioceptors
S: mechanoreceptors and nociceptors
joint capsule of synovial joints
