Task 5 Flashcards
What factors play in the human sensorimotor system?
The skeletal system, the spinal cord, brain stem and the higher brain regions
What does the skletal system have attached to itself?
skeletal muscles
what are skeletal muscles?
muscles connected by tendons
Where can bones move?
At joints
what are joints surrounded by?
a set of motor neurons
how do antagonist muscles pair up?
as flexors and externsors (biceps tricpes)
what are synergists?
muscles that work together for the same movement
what muscles are controlled by the autonomic nervous system?
smooth muscles and cardiac muscles
where are smooth muscles found?
in bronchi blood vessels stomach etc
where are cardiac muscles found?
only in the heart
what is contained in the skeletal or striated muscle?
extrafusal muscle fiber which controls the muscle´s contraction with the help of alpha motor neurons
what is the intrafusal muscle fiber sensitive to?
to muscle length
how does the intrafusal muscle fiber oinnervates contraction?
with the help of gamma motor neurons
from who does the intrafusal muscle fiber also gets infromation?
from mechanoreceptors like the parcian corpuscle
what does the parcian corpuscle reacts to?
vibration and pressure of skin
where are intrafusal musclzfibers found?
within muscle spindles
where are extrafusal muscle fibers found?
nuscle spindles on the outside
what is locate at the end of a muscle?
the golgi tendon organs which are also sensitive to stretch
what provides the force of contraction of the executed in the myofibril ?
long protein molecules actin and myosin
what happens when actin and myosin bind?
the muscle shortens and therefore contracts
what is a motor unit?
a motor neuron its axon and a muscle fibre
how do you measure a motor units activity
by the innervation ratio
what is the motor pool?
the muscle fiber a single motor neuron is connected to
what is every muscle fiber to?
a motor neuron but a motor neuron is connected with several muscle fibers
what is muscular dystrophy?
q disorder where a person suffers muscular atrophy
where is a contraction initiated?
at the neuromuscular junction
what is the neuromuscular junction?
point where the motor neuron and the muscle fiber meet
what happens when an action potential arrives?
voltage gated channels (ca2+) open releasing acetylcholine to the receptors of the muscle fiber leading to a reaction of the myofibril
what does isometric contraction and exercise imply?
that a joint and a muscle are not being moved hence a contraction strength is improved
what is a dynamic contraction?
change in mucgle legth and joint angle
which muscle fibers contract rapidly and fatigue readily?
Fast twitch muscle fibers
what muscle fibrs contract slowly and fatigue slowly too?
slow twitch muscle fibers