Chapter 5 sensory system Flashcards
Where are all sensations converted into impusles?
specialized receptors in PNS then conveyed to specific CNS targets
True or false Neural pathways for the different systems are anatomically and functionally Same
fALSE , THEY ARE DISTINCT
Mix and match the following : Chemoreceptors:
– Photoreceptors:
– Thermoreceptors:
– Mechanoreceptors:
– Nociceptors:
Chemoreceptors: smell, taste, pH, metabolite concentration
– Photoreceptors: retina
– Thermoreceptors: temperature
– Mechanoreceptors: physical deformation, most varied group: touch,
muscle tension, auditory vestibular receptors
– Nociceptors: pain
Where do the cel bodies of sensory neurons reside?
DRG and CNG – Dorsal root ganglia and cranial nerve ganglia
, in a series of ganglia alongside of the spinal cord
What is transduction?
conversion of one form of energy into
another (some physical stimulation to an electric signal–
receptor potential—that the NS can understand)
What is sensory transduction?
Conversion of pressure, touch,
heat, etc. into neural impulses
VERY IMPORTANT: nature and location of a stimulus are indicated BY?
e identities of the receptors that respond
intensity and duration of a stimulus are indicated BY?
size and duration of the receptor potential
produced.
True or False All stimuli elicit receptor potentials, but not all elicit action potentials.
True
Most sensory receptors can be thought of as
analogous ___ and adequate stimulus can be thought of as analogous to ____.
post synaptic membrane and neurotransmitters
: an area of skin where its receptive endings
reside?
A cutaneous receptor
Each receptive field (RF) corresponds to multiple afferent fiber/receptor true or false?
False - responds to single
What is the function of the receptive field?
allows the receptor to encode the location of the
stimulus
Which parts of the body have the smallest receptive fields?
Generally fine touch receptors have smaller receptive fields:Tips of
fingers, lips and tongue have the finest RF
What Slowly adapting receptors are suitable for
SSSD - shape, static position, size and duration
Rapidly adapting receptors are suitable for?
change and movement of stimuli
what kind of afferents is rapidly adapting encapsulated or non-encapsulated?
encapsulated
What purpose does a capsule around a nerve ending serve?
it acts as a mechanical filter, - modifying mechanical stimuli before it reaches the ending
Afferent neurons what do they do?
Carry information from sensory receptors found all over the body towards the central nervous system
Largest afferents supply sensory receptors to?
muscle
_ and _ are conveyed by the smallest afferent fibrees
temp and pain
Intermediate diameter fibers what do they do ?
mediate touch
Match the following receptor type to sensory function: 1. merkerl, meisner, ruffini cells pacinian , and muscle spindle, touch and proprioception
muscle spindle- proprioception, merker, etc. - touch
True or false - Receptors convey different, simultaneous and
parallel information
true - braille
what receptors repsond to pain
nociceptors
When do nociceptors respond?
only begin to respond when stimulus
reaches intensive levels and continues to increase
with the stimulus.
Pain pathway bro - what do second order neurons do?
s decussate and ascend in
the anterior-lateral spinothalamic tract, to the
thalamus
Where does the pain pathway decussate?
spinal level
What is the role of proprioceptors?
Internal information about limb position,
muscle force, muscle tension and joint stress
are conveyed by it
Which body parts have most dense muscle
spindles?
Jaw muscles and tongue
wht are muscle spindles?
Large myelinated afferents
surround muscle fibers
where does conscious perception of tactile etc. arise?
Primary sensory cortex
