NEUROBIOLOGY EXAM #3
QUESTIONS & ANSWERS
lower motor neurons - Correct Answers -motor system that conveys all commands for
movement, but reflexive and voluntary; the final common path for initiating movement;
also known as alpha motor neurons
upper motor neurons - Correct Answers -motor system that initiates voluntary
movements and is involved in complex spatiotemporal sequences of skilled movements
cerebellum - Correct Answers -motor system that detects and attenuates the difference
between intended and executed movements; mediates real-time and long-term
reduction in motor errors
basal ganglia - Correct Answers -motor system that suppresses unwanted movements
and prepares upper motor neuron circuits for initiation of movements
parkinson's - Correct Answers -disease characterized by gradual loss of voluntary
movements
huntington's - Correct Answers -disease characterized by increasing random,
uncontrollable jerking movements
upper motor neurons - Correct Answers -type of neurons that the cerebellum and basal
ganglia synapse on
motor unit - Correct Answers -made up of an alpha motor neuron/lower motor neuron
and all the muscle fibers it innervates
slow - Correct Answers -type of motor unit that is involved in activities that require
sustained muscle contraction; characterized by slow contraction and small force
fast fatigable - Correct Answers -type of motor unit that involves larger neurons that
generate more force, but fatigue easily; important for brief exertions that require large
forces, like running and jumping
fast fatigue-resistant - Correct Answers -type of motor unit that is resistant to fatigue;
generates more force then slow but less then fast
, control of posture - Correct Answers -local circuit neurons that run the entire length of
the spinal cord and connect the medial parts of the spinal cord gray matter are primarily
involved in which type of movement?
CAMs - Correct Answers -cell adhesion molecules associated with bundling of groups of
axons; calcium independent
cadherins - Correct Answers -calcium dependent cell adhesion molecules involved in
determining the final target selection
ephrins and Eph receptors - Correct Answers -cell adhesion molecules involved in cell-
cell recognition, recognizing pathways for growth and synaptic formation
lateral ventral horn - Correct Answers -where lower motor neurons are located
group II afferents - Correct Answers -neurons that are responsible for muscle tone
group Ia afferent - Correct Answers -neurons that send signal to lower motor neurons to
contract biceps and relax triceps
lower motor - Correct Answers -neurons that receive signal from group Ia afferent
neurons to contract biceps and relax triceps
local circuit neurons - Correct Answers -neurons that receive converging inputs from
several different sources before they relay signals to the muscles in the flexor reflex
patellar tendon reflex - Correct Answers -a monosynaptic reflex arc mediated by Ia
afferents
asynchronous firing of motor neurons - Correct Answers -provides a steady level of
input to the muscle, allowing movements to be executed smoothly; causes the
contraction of a relatively constant number of motor units
flexion-crossed extension reflex - Correct Answers -flexion of the stimulated limb is also
accompanied by an opposite reaction in the contralateral limb; occurs in response to
contact with a painful stimulus
cortical layer 5 - Correct Answers -cortical layer in which pyramidal cells of the primary
motor cortex are located
excitatory - Correct Answers -are pyramidal cells excitatory or inhibitory?
right internal capsule - Correct Answers -damage to this area causes immediate
flaccidity of the muscles on the left side of the body and lower face
QUESTIONS & ANSWERS
lower motor neurons - Correct Answers -motor system that conveys all commands for
movement, but reflexive and voluntary; the final common path for initiating movement;
also known as alpha motor neurons
upper motor neurons - Correct Answers -motor system that initiates voluntary
movements and is involved in complex spatiotemporal sequences of skilled movements
cerebellum - Correct Answers -motor system that detects and attenuates the difference
between intended and executed movements; mediates real-time and long-term
reduction in motor errors
basal ganglia - Correct Answers -motor system that suppresses unwanted movements
and prepares upper motor neuron circuits for initiation of movements
parkinson's - Correct Answers -disease characterized by gradual loss of voluntary
movements
huntington's - Correct Answers -disease characterized by increasing random,
uncontrollable jerking movements
upper motor neurons - Correct Answers -type of neurons that the cerebellum and basal
ganglia synapse on
motor unit - Correct Answers -made up of an alpha motor neuron/lower motor neuron
and all the muscle fibers it innervates
slow - Correct Answers -type of motor unit that is involved in activities that require
sustained muscle contraction; characterized by slow contraction and small force
fast fatigable - Correct Answers -type of motor unit that involves larger neurons that
generate more force, but fatigue easily; important for brief exertions that require large
forces, like running and jumping
fast fatigue-resistant - Correct Answers -type of motor unit that is resistant to fatigue;
generates more force then slow but less then fast
, control of posture - Correct Answers -local circuit neurons that run the entire length of
the spinal cord and connect the medial parts of the spinal cord gray matter are primarily
involved in which type of movement?
CAMs - Correct Answers -cell adhesion molecules associated with bundling of groups of
axons; calcium independent
cadherins - Correct Answers -calcium dependent cell adhesion molecules involved in
determining the final target selection
ephrins and Eph receptors - Correct Answers -cell adhesion molecules involved in cell-
cell recognition, recognizing pathways for growth and synaptic formation
lateral ventral horn - Correct Answers -where lower motor neurons are located
group II afferents - Correct Answers -neurons that are responsible for muscle tone
group Ia afferent - Correct Answers -neurons that send signal to lower motor neurons to
contract biceps and relax triceps
lower motor - Correct Answers -neurons that receive signal from group Ia afferent
neurons to contract biceps and relax triceps
local circuit neurons - Correct Answers -neurons that receive converging inputs from
several different sources before they relay signals to the muscles in the flexor reflex
patellar tendon reflex - Correct Answers -a monosynaptic reflex arc mediated by Ia
afferents
asynchronous firing of motor neurons - Correct Answers -provides a steady level of
input to the muscle, allowing movements to be executed smoothly; causes the
contraction of a relatively constant number of motor units
flexion-crossed extension reflex - Correct Answers -flexion of the stimulated limb is also
accompanied by an opposite reaction in the contralateral limb; occurs in response to
contact with a painful stimulus
cortical layer 5 - Correct Answers -cortical layer in which pyramidal cells of the primary
motor cortex are located
excitatory - Correct Answers -are pyramidal cells excitatory or inhibitory?
right internal capsule - Correct Answers -damage to this area causes immediate
flaccidity of the muscles on the left side of the body and lower face
