muscular system Flashcards
(45 cards)
Skeletal Muscle
Usually attached to bones
Voluntary control
Striated
Smooth Muscle
Walls of hollow organs, blood vessels, skin
Involuntary
Not striated
Cardiac Muscle
Wall of heart
Involuntary
Striated
Structure of a Muscle
Muscle (belly)
Fascicles
Muscle fibers
what is the muscle covered in
fascia and epimysium
Fascicles
bundles of muscle fibers
Muscle fibers
individual muscle cells
Structure of a Muscle Fiber
Sarcolemma
myofibrills
actin
myosin
sarcomeres
Sarcolemma
cell membrane of a muscle cell
Myofibrils
fundamental role in muscle contractions
actin
thin protein fillaments
myosin
thick protein fillament
sarcomeres
structural and functional unit of myofibrils
motor unit
muscle fibers controlled by motor neuron
motor neuron stimulates release of _____ a neurotransmitter
Acetylcholine
where does muscle contraction occur
neuromuscular junction
muscle impulse
chemical reaction on muscle tissue
muscle impulses release _____ into cytoplasm (part one of contraction)
calcium ions
calcium binds to _____ which changes shape (part 2 of contraction)
actin filament
actin and myosin filament binds via _____ (part 3 of contraction)
myosin cross-bridges
power stroke (cross-bridge cycling)
myosin heads pull actin towards center of sarcomere
ATP binds to _____ this is where myosin cross bridge releases
myosin
ATP is split, where does the myosin head go?
back to original spot and is ready to bind again
contractions continues as long as _____ and ___ are present
Ca and ATP