The terminal branches of the axon of a single motor neuron can synapse with up

The terminal branches of the axon of a single motor

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The terminal branches of the axon of a single motor neuron can synapse with up to 1000s of muscle fibers, forming a motor unit . A motor pool consists of multiple motor units . The vertebrate motor unit
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The vertebrate motor unit muscles performing powerful, coarsely controlled movements have larger number of fibers per motor unit example : a single calf muscle motor neuron may connect to ~2000 muscle fibers muscles that produce more precise, delicate movements contain fewer fibers per motor unit example : extraocular muscles have only ~12 muscle fibers per motor neuron A single motor unit consists of a single motor neuron and all the muscle fibers that it controls . The numbers of muscle fibers per motor unit and numbers of motor units per muscle vary widely.
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Motor units in extraocular muscles
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Treppe and summation . .
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Summation Treppe Treppe and summation
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Incomplete tetanus Complete tetanus Tetanus
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