type of reflex that initiates a response without input from the brain
spinal reflex
part of muscle fiber responsible for contraction (but does not actually shorten)
myofibril
thin filament
actin
muscle movement type when stimuli are spaced out enough to allow complete relaxation between
single twitches
muscle spindles respond mostly to this
stretch
the effector that responds to somatic motor reflexes
skeletal muscle
2 structures bound to actin to regulate movement
tropomyosin and troponin
thick filament
myosin
stimuli are close enough together that contractions are combined to reach steady tension
complete tetanus
type of movement combining reflexes and voluntary movements
rhythmic
intrafusal muscle fibers
in the rigor resting state, this is the relationship between the filaments
they are bound together
small structures of muscle fibers that appear as striations
sarcomeres
anaerobic source of energy for muscle contraction that is exhausted quickly
glycolysis
response type when someone steps on something sharp
crossed extensor reflex
stimulation of muscle spindle leads to this
muscle contraction/shortening
molecule that allows actin and myosin to separate
ATP
structure that stores calcium within muscle fibers
sarcoplasmic reticulum
molecule that allows binding between myofilaments by moving regulatory structures
calcium
type of muscle that does not have myofibrils arranged into sarcomeres
smooth muscle
stimulation of golgi tendon organs lead to this
muscle relaxation
step where myosin head swivels and actin filament moves
power stroke
a neuron and all fibers innervated by it
motor unit
molecule that triggers sodium to enter muscle fiber and start action potential
acetylcholine
information processed in multiple brain areas used to fine-tune responses
feedback