PHYS 261 Lab Quiz 4 with verified solutions

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PHYS 261 Lab Quiz 4 with verified solutions
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Explain skeletal muscle physiology
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whole muscle --> muscle fasicles --> bundles of muscle fibers (cell) -->
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myofibrils --> sarcomere || ||




What is a motor unit?
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a single motor neuron and all the muscle fibers it innervates
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What is motor unit recruitment?
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recruitment of more muscle fibers through motor unit activation
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What is a twitch?
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single stimulus-contraction-relaxation sequence in a muscle fiber
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What is summation?
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successive action potentials increase force during the period of contraction
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What is complete tetanus?
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no relaxation between contractions
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Define isometric contraction
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muscle develops tension but does not change length
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Define isotonic contraction
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muscle develops tension as it changes length
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Define concentric contraction
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shortening of muscle || ||




Define eccentric contraction
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lengthening of muscle || ||




What is the cross-bridge cycle?
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the primary source of force in muscles. made up of actin and myosin.
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