Muscle System

the neurotransmitter that gets a muscle contraction started

• acetylcholine
• serotonin
• dopamine
• acetylcholinterase

a bundle of muscle fibers

• actin
• mysoin
• fascicle
• sarcomere

the thin filament in muscle cells

• myosin
• actin
• myoglobin
• hemoglobin

the cell membrane of a muscle cell

• sarcoplasm
• sarcolemma
• sarcomere
• myofibril

the thick filament in muscle cells

• actin
• myosin
• hemoglobin
• myofibril

situation in which muscle loses its ability to contract, due to being used strenuously for a long period of time

• muscle pain
• muscle cramp
• muscle fatigue
• oxygen debt

the chemical that accumulates in muscles when oxygen is depleted

• myoglobin
• hemoglobin
• lactic acid
• carbon dioxide

the amount of muscle contraction that occurs even when a muscle is at rest

• muscle fatigue
• action potential
• threshold
• muscle tone

segment of myofibril extending from one z-line to the next

• sarcolemma
• sarcoplasm
• sarcomere
• fascicle

amount of oxygen needed to restore levels of ATP and creatine phosphate in muscles plus the amount of oxygen needed to convert the lactic acid back into glucose

• muscle tone
• muscle fatigue
• oxygen debt
• pyramiding