生命在于运动，没有运动就没有生命。在人体内，由骨、骨连结和骨骼肌三种器官共同组成的、用以专门完成人体的各种运动的系统叫做运动系统。骨以不同形式连结在一起，构成骨骼。骨骼形成了人体的基本形态，并为肌肉提供附着，在神经支配下，肌肉收缩，牵拉其所附着的骨，以可动的骨连结为枢纽，产生杠杆运动。
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