Structure of the skin. The structure of the skin. Vector illustration

illustration  Muscle Tissues  Each skeletal muscle fiber has many bundles of myofilaments  Each bundle is called a myofibril  This is what gives the muscle its striated appearance  The contractile units of the cells are called sarcomeres   

插图肌肉组织每条骨骼肌纤维都有许多束纤维丝，每束纤维称为肌原纤维。这就是使肌肉具有横纹的外观。细胞的收缩单位称为肉瘤

图像库的插图肌肉组织每条骨骼肌纤维都有许多束纤维丝，每束纤维称为肌原纤维。这就是使肌肉具有横纹的外观。细胞的收缩单位称为肉瘤 图像 Image 17878654.

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https://previews.123rf.com/images/designua/designua1302/designua130200008/17878654-插图肌肉组织每条骨骼肌纤维都有许多束纤维丝，每束纤维称为肌原纤维。这就是使肌肉具有横纹的外观。细胞的收缩单位称为肉瘤.jpg