ANATOMY
MUSCULOSKELETAL AND SOFT TISSUE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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They are slow contracting
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The are easily excitable
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They are fatigue resistant
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They are utilised for high force activities
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Detailed explanation-1: -A small motor unit is an arrangement where a single motor neuron supplies a small number of muscle fibers in a muscle. Small motor units permit very fine motor control of the muscle. The best example in humans is the small motor units of the extraocular eye muscles that move the eyeballs.
Detailed explanation-2: -Answer and Explanation: The correct answer is a) a single neuron and all the muscle cells it innervates. The motor unit specifically includes a motor neuron and all of the muscle cells that the neuron will go to innervate.
Detailed explanation-3: -The correct answer is option C because the flexor muscles of the digits have the smallest motor units as motor neurons that innervate fewer muscle fibers means that the muscle will have more innervation and thus, more fine control, as do the flexor muscles of the digits.
Detailed explanation-4: -Muscles that control eye movement and muscles in our hands have relatively small motor units. On the other hand in muscles involved with more powerful but less coordinated actions, like the muscles of the legs and back, the motor units are large with 1000s of muscle fibers per motor neuron.