skeletal muscle Flashcards
(26 cards)
in slow twitch/oxidative muscle type, what is the speed of development of max tension? in fast/glycolytic?
slow
fast
what is myosin ATPase activity in slow and fast?
slow
fast
what is the diameter in slow and fast?
small
large
what is the contraction duration in slow and fast?
long
short
what is the ca2+ ATPase activity in the SR in slow and fast?
moderate
high
what is the fatigue level in slow and fast?
fatigue resistant
easily fatigued
what is the use for the slow and fast?
most used; posture muscles
least used; jumping
what is the metabolism in slow and fast?
oxidative; aerobic
glycolytic
what is the capillary density in slow and fast?
high o2
low o2
what is the amount of mitochondria in slow and fast?
a lot of mitochondria
few mitochondria
what is the color in slow and fast?
dark red (bc of myoglobulin)
pale
what are two types of fatigue?
central fatigue from the CNS and peripheral fatigue from PNS
even if there are continuous stimuli, can fatigue still happen?
yes
what are reason for fatigue from the CNS?
psychological effects, protective reflexes to prevent injury
what are reasons for fatigue from the PNS?
not enough neurotransmitter release, not enough Ca2+ release, not enough Ca2+ and troponin interaction
what is isotonic contraction?
the contraction leads to moving the weight.
when the muscle contracts and shortens
what is isometric contraction?
the contraction doesn’t lead to moving the weight.
the muscle contracts but doesn’t shorten
what do proprioceptors detect?
detect change in positions
what do muscle spindles detect?
muscle stretch and maintains muscle tone
what fibers wrap around a muscle spindle?
intrafusal, extrafusal, and sensory
muscle spindles let the CNS know what 2 things?
how much the muscle fibers are stretching (if it is over stretching) and if the muscle tone isn’t in the optimal resting length
what does the golgi tendon organ do?
Tt responds to muscle contraction/tension during isometric contraction. The tendon stretches while the muscle contracts.
what does the golgi tendon reflex do?
protects the muscle from excessively heavy loads by causing the muscle to relax and drop the load
explain what goes on during the patellar tendon (knee jerk) reflex
stimulus: tap on the tendon below the knee which stretched the muscle
receptor: the muscle spindle stretches and fires
afferent path: action potential travels through the sensory neuron
integrating center: sensory neuron synapses in the spinal cord
efferent path #1: somatic motor neuron
effector #1: contracts quadriceps muscle (extends leg)
response: quadriceps contract, swinging leg forward
efferent path #2 (inhibitory): interneuron inhibits somatic motor neuron
effector #2: inhibits hamstring muscle
response: hamstring says relaxed, allowing extension of leg (reciprocal inhibition)