Ch 46 (test 1) Flashcards
what are the 5 types of sensory receptors
1-mechanoreceptors 2-thermoreceptors 3-nociceptors 4-electromagnetic receptors 5-chemoreceptors
mechanoreceptors are stimulated by what
compression or stretching
thermoreceptors are stimulated by what
temp and change in temp
nociceptors are stimulated by what
pain (chemical)
electromagnetic receptors are stimulated by what
eye, light
chemoreceptors are stimulated by what
taste, smell, oxygen, osmolarity
change in membrane potential of the receptor
receptor potential
depolarization is caused in sensory receptors by what
change in membrane potential caused by changes in membrane permeability
deformed area of a mechanoreceptor causes what channel to open
Na channel opens, Na flows in
a decrease in impulse rate following a receptor stimulation
adaptation
what is a pacinian corpuscle
nerve fiber and outer capsule making up a mechanoreceptor on the skin
when does adaptation occur in a pacinian corpuscle
fluid redistributes
progressive inactivation of Na channels
accommodation
what are the general classifications of nerve fibers
A (alpha, beta, gamma, delta)
C
which general classification of nerve fibers are unmyelinated
C
What are the sensory classifications of nerve fibers
I, II, III, IV
which sensory nerve fibers classification is unmyelinated
IV
define spacial summation
increased signal strength by using more fibers
define temporal summation
increase signal strength by increasing frequency of nerve impulse
many nerve cell bodies together in one area
neuronal pool
where are neuronal pools located
- nuclei in the brain
- ganglia in PNS
- gray matter in cord
- cerebral cortex
difference between facilitated and discharge zone
discharge–main area of input nerve fiber
facilitated–outskirts of input nerve fiber
what is an amplifying divergence of signals in a neuronal pool
one signal spreads to many
what is a multiplying tract of signals in a neuronal pool
signal transmitted to different paths
excitatory and inhibitory output signals found in neuronal pools
reciprocal inhibition circuit
a prolonged output discharge
afterdischarge
an input neuron releases a long acting NT that keeps sending an AP by keeping neuron depolarized
synaptic afterdischarge
reverberatory circuit
positive feedback within the neural circuit
what 2 types of signals attribute to continuous signal output
1–intrinsic neuronal discharge
2–reverberatory signal
what causes a a continuous signal output
high resting membrane potential or low threshold
