Muscle/StructureofMuscle/SkeletalMuscleStructure
Skeletal muscle structure
A whole skeletal muscle (such as the biceps) is made up of a number of fascicles. A fascicle is made up of a group of muscle fibers (cells) with associated blood vessels and nerves. Within each muscle fiber are a number of myofibrils that run the entire length of the fiber.
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Muscle fibers are long cylindrical multinucleated cells that run the whole length of the muscle. Note the alternating light and dark bands that run along each fiber, this is why skeletal muscle is said to be striated.
Challenge Quiz
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<GIFT> //LEVEL:2 //RAND Skeletal muscle fibers are grouped together in {~whole muscles~=fascicles}.
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Skeletal muscle fascicles group together to form {~=whole muscles~muscle fibers}.
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Muscle fibers are normally {~=long~short} {~=cylindrical~round} cells.
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How many nuclei does a muscle fiber have? {~none~one~=many}
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Skeletal muscle is also known as {~=striated~smooth} muscle.
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Muscle fibers contain {~=myofibrils~fascicles} that {~are short~=run the length of the fiber}.