PHYSIOLOGY
MUSCLE CONTRACTION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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myofibril
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motor unit
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Either A or B
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None of the above
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Detailed explanation-1: -The combination of an individual motor neuron and all of the muscle fibers that it innervates is called a motor unit. The number of fibers innervated by a motor unit is called its innervation ratio.
Detailed explanation-2: -Motor Units As you have learned, every skeletal muscle fiber must be innervated by the axon terminal of a motor neuron in order to contract. Each muscle fiber is innervated by only one motor neuron. The actual group of muscle fibers in a muscle innervated by a single motor neuron is called a motor unit.
Detailed explanation-3: -The muscles fibers within a muscle group are innervated by motor neurons. Any given muscle fiber is innervated by just one motor neuron. A motor neuron and the muscle fibers it innervates are called a motor unit. The muscle fibers within a motor unit usually have similar mechanical properties.