Muscle Flashcards
individual muscle cell/ muscle fiber
myocyte/ sarcocyte
muscle cytoplasm
sarcoplasm
muscle plasma membrane or plasmalemma
sarcolemma
muscle type responsible for movement of skeleton that is under voluntary control
skeletal muscle
____ % of body mass is skeletal muscle
40 %
_____ synthesize contractile proteins which assemble into sarcomeres
myotubes
connective tissue that surrounds individual muscle fibers
endomysium
several muscle fibers bound together into _____
fascicles
connective tissue surrounding fascicles
perimysium
entire muscle. surrounded by _____ and is continuous with tendinous attachment
epimysium
type of muscle fibers that are small fibers with large amounts of myoglobin; use primary aerobic respiration for oxidative metabolism; large number of mitochondria; resistant to fatigue
type 1 slow twitch fibers
type of muscle fibers that are large with less myoglobin and fewer mitochondria; use primary anaerobic glycolysis from energy production; abundant glycogen; extensive sarcoplasmic reticulum for rapid Ca release; fatigue rapidly
type 2 fast twitch fibers
breakdown of actin and myosin from extreme exertion
rhabdomyolysis
increase in cell size coming with exercise; due to increase of mitochondria and volume of contractile proteins
hypertrophy
decrease in cell size due to immobilization or disuse
atrophy
with increased age, progressive loss of skeletal muscle fibers not replaced
sarcopenia
small myogenic cells adjacent to sarcolemma that proliferate following injury and differentiate into myoblasts; primary regeneration of skeletal muscle
satellite cells
modified skeletal muscle fibers called ______ associated with modified nerve endings
intrafusal fibers
muscle spindles located within belly of muscle that are sensitive to changes in length
neuromuscular spindles
golgi tendon organs located within tendon sensitive to changes in tension
neurotendinous spindles
individual muscle fibers are composed of ____
myofibrils
myofibrils composed of numerous ______ or _______ in parallel bundles
myofilaments; contractile proteins
thin myofilament
actin
thick myofilament that gives skeletal muscle its striation
myosin
actin and myosin present in __:___ ratio in skeletal muscles
2:1
actin and myosin overlap in ___ band but not in ___ band
A; I
myofibrils arranged in ___ which are functional units of M cells
sarcomeres
______ act as anchoring points for actin myofilaments
z-discs
site where skeletal muscle innervated by motor nerve
neuromuscular junction