1.5 Sensory Receptors Flashcards
Which types of neurones are unipolar or multipolar?
Unipolar - sensory
Multipolar - motor
Where are cell bodies of motor neurons and sensory neurons situated?
Sensory cell bodies - DRG
Motor cell bodies - spinal cord
Are the sensory neuron cell bodies found in the CNS?
somatic sensory afferent fibre cell bodies lie in the cns - spine
Are motor and sensory neurons myelinated?
Motor - myelinated
sensory - both myelinated and unmyelinated
What are the two classifications of peripheral nerves and for which nerves are they for?
Roman - only sensory
Letter - both motor and sensory
What happens to the diameter and speed of conduction when you go down both of the classifications?
Diameter decreases and velocity decreases
Name the classifications of nerves linked to; muscle spindle, golgi tendon organ, touch & pressure, pain & cold receptors, pain & temp.
Muscle spindle - Ia & Aalpha Golgi tendon - Ib & Aalpha Muscle spindle, touch and pressure - II & Abeta Pain and Cold - III & Adelta Pain & Temp - IV & C
Explain sensation and perception
Sensation - conscious or subconscious awareness of the environment
Perception - interpretation of the sensation
Name the 2 types of modalities
General and Special
What are the 2 types of general senses?
Visceral and Somatic
Name the three types of sensory receptors and explain them
Microscopic - free nerve endings etc.
Stimulus - mechano, chemo etc
Location - intero, extero & proprio
Hair follicle…
Unencapsulated, A beta/II, myelinated
meissner corpuscle…
Encapsulated, A beta/II, myelinated, tap flutter, 5 - 40 Hz
ruffini corpuscle …
Unencapsultaed, A beta/II, myelinated, skin stretch and slippage
merkel cells…
Unencapsulated, A beta/II, myelinated, touch & pressure
Pacinian cells…
Encapsulated, myelinated, A beta/II, vibration, 60 - 300 Hx
Free nerve endings…
Nocireceptors,
A delta - myelinated, sharp pain, III
C fibre - unmyelinated, dull pain, IV
Why does coding of sensory information occur?
When the tonic firing changes - change of frequency/rate, duration of APs, or activation of another sensory receptor
Name the receptors which are Rapid acting and Slow acting
Rapid acting - large frequencies, transient, phasic or vibratory - messier and pacinian
Slow acting - change of intensity or duration - ruffini & merkel